Driving Discoveries 2022: abstracts

Fiona Chapman

Authors and affiliations (if published): 

Fiona A. Chapman, David E. Newby, Neeraj Dhaun (Bean) 

Centre for Cardiovascular Science, Queen’s Medical Research Institute, University of Edinburgh 

Background: 

Chronic kidney disease (CKD) affects one in ten people and cardiovascular disease (CVD) is its commonest complication. Despite standard-of-care, many patients with CKD progress to kidney failure and/or die of CVD. Apelin is an endothelium-dependent vasodilator and an attractive therapeutic target for CKD. We examined, for the first time, the local vascular actions of apelin in CKD.  

Methods: 

We recruited 15 patients with non-diabetic CKD and 15 age, and sex-matched healthy volunteers. We assessed blood pressure (BP) and arterial stiffness (pulse wave velocity, PWV), and examined vasodilatory responses to acetylcholine (ACh, endothelium-dependent vasodilatation), sodium nitroprusside (SNP, endothelium-independent vasodilatation), and pyroglutamated apelin-13 ([Pyr1]apelin-13) using gold-standard forearm plethysmography. To assess the effect of apelin on endogenous fibrinolysis, we measured tissue plasminogen activator (tPA) and plasminogen activator inhibitor-1 (PAI-1). 

Results: 

CKD patients had a mean age of 55±4 years and 53% were male. Patients with CKD had a higher BP (mean arterial pressure: 102mmHg versus 93mmHg, p<0.05) and increased PWV (7.5±2.2m/s versus 6.0±0.9 m/s, p<0.01) compared to healthy volunteers. Similar dose-dependent vasodilatation to ACh and SNP was seen in both groups. [Pyr1]apelin-13 increased forearm blood flow by ~30% in both healthy patients and CKD patients (p<0.01 compared to baseline for both). Net tPA antigen release increased 20-70 fold in response to apelin in both healthy patients and CKD patients, with a trend to a greater release in CKD patients. There was no association between apelin response and kidney function. 

Conclusion: 

Apelin causes vasodilatation in optimally managed patients with CKD. Systemic studies are needed to further examine the actions of apelin in CKD. 

Lay summary: 

Kidney disease is common and affects one in 10 people. Many people with kidney disease have high blood pressure and go on to have heart attacks or strokes, and some die from this. Current treatment for kidney disease is limited and unfortunately many people still develop kidney failure. We want to find new treatments for kidney disease. Apelin is a small protein found in the body. It lowers blood pressure, helps the heart pump better and may help the kidneys get rid of salt and water. We want to see if it might be a new treatment for kidney patients that could also protect them from heart disease. We explored what apelin did to blood vessels in people with kidney disease. We gave apelin into the arms of 15 people with kidney disease and 15 healthy people and measured how well their blood vessels relaxed. Apelin caused the blood vessels in people with kidney disease to relax the same amount as blood vessels in healthy people. This is very promising. We now need to give a longer treatment with apelin throughout the body and see what happens to blood pressure, heart function and the kidneys. 

Biography:

Chronic kidney disease is a potentially devastating, life-changing condition with very few treatment options. As a renal registrar I have been fortunate to work in the renal units in both Edinburgh and Glasgow. I really enjoy working with patients and wanted to move into clinical research to try and have a greater impact for all patients with kidney disease.   

Knowledge of the apelin system has increased enormously in the last decade. Excitingly, animal studies suggest it is a new potential target for treating kidney disease. My study is the first to explore the actions of the apelin system on the kidneys in humans. This is not only essential to better understand the system but will also provide the first insight into whether it is a viable target for treating chronic kidney disease. Ultimately, my study could pave the way for larger clinical trials and the development of a new treatment for CKD.  

Being awarded a Kidney Research UK training fellowship has transformed my career. I have been incredibly privileged to work with international experts who have helped me ensure my studies are well planned and successful. I am so grateful to them, and to the patients who have taken part.

Richard Naylor

Authors and affiliations (if published): 

Richard W. Naylor, Rachel Lennon 

Wellcome Centre for Cell-Matrix Research, University of Manchester 

Background: 

Autosomal dominant polycystic kidney disease (ADPKD) is the most common, potentially life-threatening monogenic disease. A major disease feature of ADPKD is the formation of large fluid-filled sacs, called cysts, in the kidney. Over time, these cysts induce fibrosis and preclude kidney function. Half of patients with ADPKD require renal replacement therapy by the age of 60, and one in eight kidney transplants in the UK are performed on patients with ADPKD. Therefore, ADPKD places significant burden on both patients and the NHS. ~93% of ADPKD cases are caused by mutations in either PKD1 or PKD2, which encode for polycystin-1 (PC1) and PC2, respectively. ADPKD is considered a ciliopathy as PC1/PC2 form a calcium ion channel that is located at the cilium. Many studies have confirmed the role of PC1/PC2 in regulating calcium signalling and other downstream pathways, such as cAMP signalling. However, the contribution of the extracellular matrix in the early stages of ADPKD disease progression has not been assessed. Given the extracellular matrix is important in many processes and signalling pathways that are implicated in ADPKD progression, it is vital we understand how it contributes to cystogenesis.

Methods: 

Mass spectrometry-based proteomic approaches were utilised on micro-dissected zebrafish embryonic kidney tubules to determine the changes in the extracellular matrix that occur in a zebrafish model of ADPKD. qRT-PCR and immunostaining approaches were also employed to develop novel ways of determining rates of cell proliferation in this tissue.

Results: 

It was found that altering the composition of the extracellular matrix in the zebrafish embryonic kidney is sufficient to reduce cell proliferation in control and ADPKD zebrafish embryos. However, analysis of the embryonic kidney proteome in ADPKD zebrafish embryos shows little change is observed in the overall make-up of the extracellular matrix.

Conclusion:  

These results suggest that the extracellular matrix can play an important role in regulating cell proliferation in normal and ADPKD kidney tissue. However, in the earliest stages of the disease, there appears to be little change in the composition of the extracellular matrix, supporting the conclusion that matrix dysregulation is not required for the hyper-proliferation phenotype associated with cystogenesis in ADPKD.

Lay summary:  

Autosomal dominant polycystic kidney disease (ADPKD) is caused by variants in the PKD1 and PKD2 genes. The major feature of the disease is the formation of fluid-filled sacs, cysts, in the kidneys. These cysts can grow very large, to the size of golf balls in extreme cases. Half of patients with ADPKD will need renal replacement therapy by the age of 60, which places a huge burden on patient mental health and the NHS. Cysts are able to form because cells in the kidney tubules begin proliferating, enabling cyst growth. Targeting this increased proliferation is a potential therapeutic approach, and this is one of the ways that tolvaptan works to reduce cyst formation. The protein mesh that surrounds cells, called the extracellular matrix is of greatest interest. This matrix is extremely important as it enables cells to proliferate and grow, therefore I hypothesise that changes in the extracellular matrix in the early stages of ADPKD is important for cyst growth and progression of the disease.

Biography:

I am intrigued by the complex structure of the kidney and how important it is to human health, which often is not fully realised by the wider population. My career started looking at how the kidney forms, but now I am more invested in understanding how the kidney changes during disease, which often involves many developmental pathways being re-initiated.

My research is aiming to determine new paradigms in kidney disease, especially in ADPKD. I have developed new tools to aid ADPKD research and I believe understanding the under-appreciated role of the extracellular matrix is fundamental to many kidney diseases.

Kidney Research UK has offered me the amazing opportunity to work independently and guide my own research. Attending conferences such as Driving Discoveries enables me to network with people who will help my research now and in the future. The charity's patient-focus also gives me access to the people that we are doing the research for, the patients. I hope in the future such access will guide me on better understanding the areas of research that are most essential in kidney disease.

Amarpreet Thind

Authors and affiliations (if published):

Amarpreet K Thind^1,2,Annabel Rule2,3, Dawn Goodall², Shuli Levy², Sarah Brice², Frank JMF Dor^2,4, Nicola Evans⁵, David Ospalla², Nicola Thomas⁶, David Wellsted⁷, Lina Johansson^1,2, Michelle Willicombe^1,2, Edwina A Brown^1,2

¹Centre for Inflammatory Disease, Department of Immunology and Inflammation, Imperial College London,
²Imperial College Healthcare NHS Trust, Hammersmith Hospital,
³Central London Community Healthcare NHS Trust,
⁴Department of Surgery and Cancer, Imperial College London,
⁵Guy’s and St Thomas’ NHS Foundation Trust,
⁶Institute of Health and Social Care, London South Bank University,
⁷The Centre for Health Services and Clinical Research, The University of Hertfordshire.

Background: 

Older end-stage kidney disease (ESKD) patients are particularly vulnerable to developing frailty, and the presence of frailty is well recognised as impacting on clinical and experiential outcomes. With kidney transplantation rates in older people increasing, achieving a more detailed understanding of patient experiences is necessary for guiding appropriate treatment decision making.  

The “Kidney Transplantation in Older People (KTOP): impact of frailty on outcomes” study is an active study exploring the experiences of older people with ESKD awaiting and undergoing transplantation. This manuscript presents a secondary analysis of the Edmonton Frail Scale (EFS) and its relationship with patient experience scores, at recruitment into the KTOP study.  

Methods: 

The KTOP study is a single centre, prospective, mixed methods study, which began in October 2019. All ESKD patients aged ≥60 who were being considered for transplantation at Imperial College Renal and Transplant Centre were eligible. Recruited participants had their frailty assessed by the EFS and completed 5 questionnaires to assess patient experience and quality of life (Short Form- 12 (v2), Palliative Care Outcome Scale – Symptoms Renal, Depression Patient Health Questionnaire-9, Illness Intrusiveness Ratings Scale, and Renal Treatment Satisfaction Questionnaire). Categories of components within the EFS were then created to support the analysis; psychosocial, physical function, medical status, and general health status.  

Results: 

210 patients have been recruited (aged 60-78), 186 of whom had completed EFS assessments. 118 (63.4%) participants were identified as not frail, 36 (19.4%) vulnerable, and 32 (17.2%) participants were frail. Across all study questionnaires poorer patient experiences and quality of life were reported as the identified frailty status worsened. Severe deficits in the psychosocial category of the EFS showed a significant association with higher depression screen scores, lower physical and mental function scores from the Short Form-12(v2), and lower renal treatment satisfaction scores. Deficits in the physical function and medical status categories of the EFS showed some association with the patient experiences scores reported.  

Conclusion: 

In the KTOP study cohort at recruitment, vulnerable and frail candidates reported worse quality of life and patient experiences. Severe deficits in the psychosocial domains of the EFS show a strong association with patient experience and quality of life, whilst deficits in the physical function and medical status domains showed a lesser association. This study has highlighted specific domains within the EFS that may be suitable for targeted interventions to improve patient experience and optimise outcomes. 

Lay summary: 

The quality of life for older people with kidney disease is highly variable. Older people with kidney disease are at a higher risk of becoming frail, and frailty has been shown to affect their quality of life. The Kidney Transplantation in Older People study uses questionnaires to better understand the experiences of older people as they wait for and receive a kidney transplant. The study is running in West London and so far, 210 older people are involved. Early results have shown that older people who are vulnerable to frailty or already frail, do describe a poorer quality of life and experiences of living with kidney disease, compared to those who are not frail. We have also found that specific aspects of an older person’s life play a bigger role in their experiences of living with kidney disease. These include difficulties with mood, memory, taking medications and the social support they have around them. Low levels of physical activity also seem to contribute negatively. These early results have suggested areas where we may be able to better support older people as they wait for a kidney transplant, to help improve their quality of life and their experiences of kidney disease. 

Biography:   

Amarpreet Thind is a clinical research fellow at Imperial College London and the Imperial College Renal and Transplant Centre. Having graduated from Newcastle University in 2012, with an intercalated MRes degree, she is currently completing her PhD in geriatric nephrology. She is part of a multi-disciplinary team conducting the Kidney Transplantation in Older People (KTOP) clinical study. The study is exploring the impact of frailty on clinical and experiential outcomes in older people, accelerating our understanding of the unique clinical factors, influences, and priorities that drive care and decision making in this dynamic population. 

During her early registrar training Amarpreet developed a realisation for the varied and significant impact that living with kidney disease has on the everyday lives of patients, families and their carers. A desire to better understand these perspectives and find practical ways to improve clinical care drove Amarpreet to conduct and continue with renal research. Only through working with Kidney Research UK has this valuable research been possible. In addition to the essential financial support, the charity has created a collaborative, multi-professional environment, to bring the project into fruition, promote the findings, and ultimately bring us closer to providing better patient-centred care for older people. 

Dr Ben Reynolds

Authors and affiliations (if published):

Ben C Reynolds¹, Claire Hagerty¹ Vassilis Charissis², Soheeb Khan², Lyall Campbell²,

¹Royal Hospital for Children, Glasgow

²Glasgow Caledonian University

Background: 

Undertaking training of patients/families in peritoneal dialysis (PD) can be stressful for families and requires face to face availability of educators. In paediatrics, children are usually admitted for this training to occur. The rarity of paediatric kidney disease limits opportunities for families to meet peers/others, so the decision to undertake PD may not be truly informed or shared between clinicians and families. 

We hypothesized that virtual reality (VR) could offer an alternative supplemental route for training of patients, families, and staff in dialysis. We aimed to develop a prototype as proof of concept that VR is suitable for this. 

Methods: 

Qualitative interviews were conducted with families, nursing staff, and nurse educators to determine the key elements of the VR program, and main objectives that VR education could fulfil. A multimedia library was composed to permit 3D model creation of all aspects of PD. A VR application was coded and developed with stages of preparation/machine set-up, connection, and disconnection of a dialysis session. Two brief troubleshooting scenarios were also developed. Following feedback from medical and nursing staff, a tutorial was added and several adjustments made to the program. Several iterations were completed with feedback from staff members at each stage. 

Results: 

A prototype VR PD educational tool has been developed for use with the MetaQuest 2 VR headset.  Informal feedback sought from patients and families familiar with PD has been generally very positive. One parent had significant motion sickness and could not tolerate use of the headset. One family with experience of VR and PD reported the application was ‘epic’. Two families have trialled the tool prior to undertaking any education in PD – both reported that the tool alleviated anxiety, and that they could relate the VR experience to their training or nurses setting up the machine on the ward. For the one family who have since completed face to face training, this took three days (usually five to seven in our unit). 

Conclusion: 

VR offers a potentially very useful supplement to training in medical technologies such as dialysis. Training duration for families may be shortened. Formal evaluation of the application’s utility as an educational tool is needed, as is objective evidence of its benefit to patients/families. Multiple potential alternative uses of VR in medical education also exist. 

(One aspect of evaluation planned for August 2022 but not available at time of abstract submission) 

Lay summary: 

Learning how to do dialysis at home can be stressful for patients and families.  For children, families may not have the opportunity to meet with dialysis-experienced patients as end stage kidney disease is rare. Parents may have to decide on the type of dialysis, or agree to undertake dialysis training, without a full understanding of what this entails. 

We have developed a prototype virtual reality application which provides a realistic simulation of setting up, connecting, and disconnecting a peritoneal dialysis session for a child. Interviews with families, nursing staff, and nurse specialists, helped identify the key areas that training should cover. A multimedia library was created to allow recreation of all aspects of a dialysis session. The program was developed, with several versions tested by medical and nursing staff to identify any areas that needed to change. 

A small number of families have tried out the application – all were impressed with it and reported that they could see a real place for it in training patients in the future. Two families used the application before any kind of training – both said it was very helpful and made them less stressed before starting. A formal assessment of the application is planned. 

Biography

Ben is a consultant paediatric nephrologist based at Royal Hospital for Children, Glasgow, and the clinical lead for transplantation.  His interests include the immunology of transplantation, managing the challenges associated with adolescence and transition to adult care, and the patient experience/journey. 

The pandemic brought challenges and isolation for many.  Ben staved off some of the isolation by immersing himself in the virtual reality world and realised that there was real potential for these tools to be used for patient and family education.  Similar enthusiasm from Kidney Research UK has provided funding for the development of these tools.   

Being directly involved in kidney research is always exciting. Being able to witness the direct impact of research findings on patients and families is a privilege for all clinicians; being able to also contribute to that research is even more powerful. 

Simon Baker

Authors and affiliations (if published):

S.C. Baker^1,*, A.S. Mason¹, R.G. Slip¹, K.T. Skinner¹, A. Macdonald², M. Wellberry-Smith³, O. Masood³, R.S. Harris⁴, T.R. Fenton⁵, M. Periyasamy⁷, S. Ali⁷ and J. Southgate¹

_{1Jack Birch Unit for Molecular Carcinogenesis, Department of Biology and York Biomedical Research Institute, University of York, UK.
²Faculty of Biological Sciences, School of Molecular and Cellular Pathology, University of Leeds, UK.
³Leeds Kidney Unit, St James’s University Hospital, UK.
⁴College of Biological Sciences, University of Minnesota, USA.
⁵School of Cancer Sciences, University of Southampton, UK.
⁶Department of Surgery & Cancer, Imperial College London, UK.}

*Presenting author

Background: 

Age and smoking are the main risk factors for bladder cancer. However, studies of mutational signatures show the anti-viral apolipoprotein B mRNA editing enzyme catalytic polypeptide (APOBEC) enzymes, and not smoke-derived carcinogens, are responsible for the preponderance of mutations in bladder tumour genomes. BK polyomavirus (BKPyV) infects >80% of the population in childhood and infections persist into adulthood by lying dormant in the renal epithelium. Persistent BKPyV infections can be reactivated in the adult kidney at times of immune-insufficiency (due to aging or immuno-suppression), leading to viruria. 

Methods: 

We used two models of mitotically-quiescent normal human urothelium to study sequalae of BKPyV infection; an in vitro tissue-engineered model and a ureteric organ culture system. Post-infection urothelia were evaluated using RNA-sequencing, western blotting, immunolabelling and APOBEC-activity assays. Host genome damage was assessed by quantifying apurinic/apyrimidinic sites. 

Results: 

BKPyV infection significantly elevated APOBEC3A/B proteins, deaminase activity and numbers of apurinic/apyrimidinic sites in the host urothelial genome. Large T antigen (LT-Ag) pushed mitotically-quiescent urothelial cells into an arrested G2 cell cycle state where Rad51-mediated DNA-displacement loops formed during homologous recombination potentially provide a single-stranded DNA substrate for APOBECs. Proximity ligation assays indicate LT-Ag interacts with both Rad51 and APOBEC3 proteins at DNA-displacement loops. In vitro findings were validated in organ cultures, where infected cells were extruded apically from the urothelium in a manner synonymous with production of decoy cells in patients. 

Conclusion: 

These initial results support reactivated BKPyV infections in adults as a risk factor for bladder cancer in immune-insufficient populations, including transplant patients and the elderly. As further validation, nanorate sequencing will compare mutational signatures from in vitro infections to those of bladder cancers. 

Lay summary: 

BK virus infects most children without obvious symptoms and can hide, dormant in the kidneys during adulthood. We don’t understand what triggers the sleeping virus to awaken, but this reactivation can happen in around one-in-five kidney transplant patients due to the medication used to prevent  transplant rejection called immunosuppression). 

When kidney cells sense that they have a BK virus infection, they slough off into the urine. Infected kidney cells also release virus into the urine. Once it has left the kidneys, urine travels down the tubes of the ureter and into the bladder, where it is stored until a person urinates.  

This study found BK virus infects human bladder cells leaving changes in the DNA that could lead to cancer. This study is especially relevant to kidney transplant recipients, but has wider implications for others who develop bladder cancer in old age.  

We know kidney transplant patients develop ureter and bladder cancers much more frequently than the general population, but currently it is not clear how this happens. We are working with kidney and bladder clinical specialists to understand whether BK virus infections lead to the increased risk of urinary tract cancers in kidney transplant patients.  

Biography:

My research seeks to understand the causes of bladder cancer. Following the evidence led me to persistent polyomavirus infections of the kidney as a potential risk factor. Our building evidence suggests understanding how persistence and reactivation of polyomaviruses in the kidney are regulated may hold the key to preventing bladder cancer as well as nephropathy and graft-rejection in transplant recipients. 

My Kidney Research UK fellowship is acting as a focal point to reignite old initiatives and start new activities in the BK polyomavirus field. We are bringing together diverse experts in the field and there is a real buzz around BK virus research, both in the UK and internationally. 

My Kidney Research UK fellowship has given me the independence and resources to ask the biggest questions in my field and the charity’s relationship with patients is helping us drive change in clinical practice. 

Claudia Bruno

Authors and affiliations (if published):

Claudia Bruno¹, Rayan Moumneh¹, Lynsey Stronach², Emilie Sauvage¹, Ian Simcock², Silvia Schievano^1,2, Rukshana Shroff^1,2, Claudio Capelli^1,2.

¹University College London, Institute of Cardiovascular Science (London, UK)
²Great Ormond Street Hospital for Children, NHS Foundation Trust (London, UK)

Background: 

Central venous lines (CVLs) used for haemodialysis (HD) in children are associated with a high complication rate leading to inadequate HD and line replacement in nearly half of the patients. Computational modelling and simulations are powerful engineering tools that use computers to study complex systems by means of mathematics, physics and computer science. This project aimed at providing a computational fluid dynamics characterization of CVLs commonly used in children to understand the causes of their complications, and to improve their performance by optimizing their design. 

Methods: 

Four models of CVLs of varying design and sizes (6.5Fr, 8Fr, 10Fr and 14Fr) were recreated starting from medical images. Each design presented multiple ports for blood exchange (i.e. tip and side holes). Computational fluid dynamics (CFD) analyses were set up to simulate the CVLs’ performance under both ideal and realistic models of superior vena cava. A variety of flow rates, routinely used in real hospital settings, were applied to study the whole range of working conditions. Haemodynamics features were analysed together with the effect of the catheter insertion inside the vein. CFD findings were then compared to clinical CVLs outcomes from patients (n=26 with 57 lines) over the past two years. Fluid dynamics characteristics of the CVLs studied were used to set up a preliminary design optimisation process. 

Results: 

In all the simulated CVLs, the arterial lumens, where blood is withdrawn from the body, showed the highest stagnation and recirculation areas.  The role of arterial tips appeared to be negligible for the blood exchange and the proximal side holes played a major role for blood aspiration being also subject to the highest levels of shear stress (Figure 1a), regardless of the design. In all the anatomical models, blood velocity increased after catheter insertion (Figure 1b) together with wall shear stresses. CFD results were in accordance with the clinical data which showed a higher recurrence rate of thrombosis for the 8Fr and 10Fr CVLs. Also, microCT images of the explanted lines confirmed presence of thrombosis at the level of the catheter tips. Results suggested that the shear stress is the parameter more strongly related to clinical complications. Preliminarily optimised designs showed a better haemodynamic performance, reducing stagnation areas (Figure 1c). 

Conclusion: 

In this project, we carried out the fluid dynamics characterisation of commercially available CVLs for paediatric use to try to explain the associated clinical outcomes. This process will guide the optimisation of their design. 

Figure 1: a) Shear stress levels contours plotted for the 10Fr model. Velocity magnitude contours: b) inside the vein after CVL insertion; c) inside a 6.5Fr model before and after optimisation to reduce stagnation areas.

Lay summary: 

Haemodialysis is a life-saving treatment for children with kidney failure. Central venous lines (CVLs) are the tubes most commonly used for dialysis access. Although ‘lifelines’ for dialysis patients, CVLs are fraught with complications like poor blood flow, clots and infections. In an international study 45% of all CVLs needed replacement due to complications. This results in hospitalisations and multiple operations to replace failing lines, damages the child’s vessels and limits their quality of life. Currently available CVLs are simply miniaturised versions of adult CVLs, and not optimised for the child’s anatomy or blood flow characteristics. In this project we have used a bioengineering approach to better comprehend the fluid dynamics in CVLs and to address their high failure rate. A bioengineering approach can provide data on the fluid dynamics inside the line and can be used to address the high failure rate of paediatric CVLs. We have evaluated different CVL designs currently in use in children and correlated clinical data with engineering results. These results will allow us to set up the optimisation process which will lead to new designs with better flow distribution and low level of damage to blood cells.  

Biography:

During the final year of my MSc in biomedical engineering, I had the opportunity to research central venous line performance for paediatric dialysis in collaboration with clinicians at Great Ormond Street Hospital and engineers from University College London. In those six months I came to understand the severity of kidney disease and the importance of the dialysis treatment for paediatric patients. What surprised me the most was that, despite the high rate of complications that paediatric patients encounter due to the poor performances of central venous lines, there was a lack of engineering studies which sought to uncover the underlying causes and address them. The potential impact that advanced engineering studies can have on improving the quality of patient’s treatment keep me in renal research and is the focus of my current research.

Kidney Research UK is a vibrant community that gave me the opportunity to conduct my research and present my findings to other researchers, clinicians and, most importantly, to patients. Lastly, the MedTech Academy Programme offered by Kidney Research UK has been extremely useful and helped me gain skills to successfully translate research into the market and build a network of like-minded people in the renal community.  

Authors and affiliations (if published):

Katia Nazmutdinova

Katia Nazmutdinova^1,4, Cheuk Yan Man¹, Philip Beales², Karen Price¹, Stephen Walsh³ and David Long¹

¹Kidney Development and Disease Group, Developmental Biology and Cancer Department, University College London, London, UK
²Genetics & Genomic Medicine Department, University College London, London, UK
³Department of Renal Medicine, University College London, London, UK
⁴Encelo Laboratories, UK

Background: 

Urine has emerged as a non-invasive source of patient-specific renal cells, however reliable cell extraction has not been demonstrated yet, largely due to the short shelf life of samples and poor and inconsistent recovery rates, reported in the literature. This project is set to optimise the current centrifugation method for cell isolation and preservation from urine samples. 

Methods: 

We custom-built a unique benchtop filtration unit, a Cell Catcher, for processing urine samples in clinical settings, without the need for any equipment and compared its efficiency to the current gold standard, centrifugation. Sixty-three fresh urine samples were collected from healthy individuals and patients affected by rare genetic conditions, with or without kidney involvement (Bardet-Biedl Syndrome patients and various tubulopathies patients). Samples were processed either using the Cell Catcher (Clinic Edition) (Encelo, UK) within 30 minutes of collection, on-site, or transported to the lab on ice to be centrifuged within 4 hours. Urine-derived pellets were plated and maintained in culture for 4-6 weeks. Colonies were quantified manually during the second week of culturing, while RNA was extracted from cells at passage 1 for gene expression analysis.  

Results: 

We report that cell cultures can be established in up to 90% of samples, if they are processed in the Cell Catcher, an increase of 26%, compared to centrifugation. In addition, we report higher cell yield in Cell Catcher-processed samples, with a high degree of variation in colonies formed per sample among patients (1-200), but not in healthy controls (1-12). We have successfully expanded cells from patients and report achievable cell yields of 0.5-2.2 million within 2 weeks. Our study has confirmed that the majority of the urine-derived cells express proximal tubule cell markers.  

Conclusion: 

Cell Catcher standardises urine processing method and captures more viable cells from more samples, compared to conventional centrifugation method. It solves logistical issues associated with immediate access to laboratory equipment currently needed to retrieve viable cells. This advancement aims to help facilitate research in personalised medicine in the renal field and beyond, by turning biowaste into valuable patient-specific cells more efficiently. 

Lay summary: 

Every day, dozens of cells, originating from the kidney are shed in urine, as part of normal physiological processes. Studying these cells in a dish from patients, affected by or predisposed to renal disease, can help researchers to understand the mechanisms underlying kidney disease and identify novel diagnostic tools and personalised treatments. Current methods of cell extraction from urine samples have a low probability of success and require almost immediate processing of samples in laboratory settings, which means that patients must travel to the hospital to provide a sample and participate in research. However, an alternative method is currently under development. It is a novel point of care device Cell Catcher, which allows patients to collect their samples in the comfort of their home, and then simply mail them to the laboratory, with live cells preserved. We have demonstrated up to 90% efficiency of the beta version of Cell Catcher as part of a validation study using over 60 urine samples, as part of the feasibility study conducted by biotech start-up Encelo and UCL. By turning biowaste into valuable patient-specific cells we believe this will help advance scientific knowledge in the renal field, leading to faster diagnoses and treatments. 

Biography: 

Dr Katia Nazmutdinova is a geneticist with a passion to make patient-specific kidney cells more accessible for research, improving the translatability of studies. She obtained her PhD in Genetics of Rare Diseases at University College London in 2018. Katia was studying urine-derived cells of renal origin, extracted from patients affected by a rare genetic condition, Bardet-Biedl Syndrome. A major limitation of the study was a low success rate of cell extraction, reliance on rapid lab-based centrifugation and infrequent patient visits. Katia decided to develop a user-friendly pee cup that can be sent to patients, for live cells to be collected by post.  

She launched the company to develop the device Cell Catcher in 2018, securing pre-seed funding from the private sector and an innovation grant in paediatrics from Kidney Research UK in 2021.  The grant enabled the first functional prototype to be built and tested, in collaboration with a nephrology group led by David Long at the UCL Great Ormond Street Hospital Institute of Child Health. Turning biowaste into valuable patient-specific cells more efficiently will help advance scientific knowledge in the renal field, leading to faster diagnoses and treatments, as well as opening new routes in biobanking. 

Christina Pearce

Authors and affiliations (if published): 

Christina Joanne Pearce* and Natalie Hall  

*Kings College, London 

Background: 

Depression is common within patients with chronic kidney disease (CKD) and is correlated to poorer quality of life, worse clinical outcomes and greater healthcare costs. Little is known about how depression is identified and managed in practice within the UK. Prior to the coronavirus-19 pandemic Seekles and colleagues mapped the UK renal psychosocial workforce and found that none of the renal centres met the recommended benchmark of social worker to patient ratios as set out in the 2002 workforce report and only four units met the recommended psychologist to patient ratios. The aim of this study was to assess the variability in psychosocial care for patients with CKD across UK renal centres. 

Methods: 

All 71 adult renal care centres across the UK were invited to take part in the online survey. The survey was comprised of three sections: 1) general kidney treatment and patient profile, to be completed by the clinical director or lead nurse, (2) psychological support, to be completed by psychological support staff, as identified in section 1, and (3) social work support, to be completed by social work staff, as identified in section 1. The survey was circulated on the 4 December 2021 and closed on the 31 April. Due to the small number descriptive statistics are predominant utilised for this analysis conducted in STATA. 

Results: 

Of the 71 centres invited to take part 56 centres (79%) opened the survey. Valid responses were given by 41 (58% response rate) Clinical Directors/lead nurses, 19 responses for the psychology module (where applicable) and 14 responses from the social work module (where applicable). Centres from England, Scotland, Wales and Northern Ireland responded to the survey. Of the centres that responded, acute transplant surgery was the group with the least provision for psychosocial care (n=15, 37%). Cognitive behavioural therapy is the most common psychological intervention provided (79% of respondents). The majority of respondents had a dedicated in-centre social worker (83% of respondents to the social work module). Psychologists reported that 84% of their services had formal referral pathways into their services.  

Conclusion: 

Less than half of all adult renal centre respondents had psychology and/or social work provision. Where the psychosocial modules were completed by relevant staff, the renal services often have dedicated social workers and a formal pathway for the identification and management of depression and/or anxiety. This survey highlights the psychosocial provision environment and areas for improvement.   

Lay summary: 

Depression is common within patients with chronic kidney disease (CKD) and is related to a lower quality of life and worse health outcomes. Little is known about how depression is identified in patients and managed in UK kidney centres. Before the coronavirus-19 pandemic research that mapped the UK kidney psychological and social workforce identified low levels of social workers and psychologists compared to the recommended numbers.  

The aim of this study was to assess the variability in psychosocial care for patients with CKD across UK renal centres. The study survey, sent to 71 adult kidney centres across the UK, was made up of 3 sections: general questions for the medical team, one section for the social worker and one for the psychologist.  

Forty-one centres (58% of the UK centres) responded to the survey with usable information. Responses came from centres from all countries in the UK. Psychologists reported cognitive behavioural therapy to be the most common talk therapy for depression (79%) and that formal referral routes were available in 84% of centres with psychological care providers. Less than half of all adult kidney centres who responded to our survey had psychology and/or social workers as part of their team. 

Biography:

Christina is a chartered psychologist who joined King’s College London in 2020 as a postdoctoral research associate in the health psychology section. Her current research focuses on evaluating services for the identification and management of depression in people with chronic kidney disease across the UK. 

Christina gained her PhD from University College London, Centre for Behavioural Medicine in 2020 which explored the reasons for and patterns of non-adherence to inhaled medication in paediatric patients with severe asthma. Christina’s research focuses on living with long-term conditions in terms of health behaviour, self-management and accompanying mental health issues. Christina’s work in health psychology has spanned several conditions including medically unexplained symptoms, psoriasis, psoriatic arthritis, cardiovascular disease, asthma, polypharmacy, and chronic kidney disease. 

Monica Gamez

Authors and affiliations (if published):

Monica Gamez¹, Hesham El Hegni¹, Sarah Fawaz¹, Matthew Butler¹, Elizabeth Wasson¹, Michael Crompton¹, Raina Ramnath¹, Yan Qiu¹, Jerry Turnbull², Olga Zubkova³, Gavin Welsh¹, Simon Satchell¹, Rebecca Foster.¹

¹Bristol Renal, Bristol Medical School, Dorothy Hodgkin Building, University of Bristol, Whitson St, Bristol, UK. BS1 4NE. Corresponding author: [email protected]
²Department of Biochemistry, University of Liverpool, Liverpool, UK. L69 3BX
³Ferrier Research Institute, 69 Gracefield Rd, Lower Hutt, Victoria University of Wellington, New Zealand.

Background: 

An estimated 647 million people worldwide will have diabetes mellitus (DM) by 2040, which causes life altering microvascular complications, such as diabetic nephropathy (DN). The endothelial glycocalyx (eGlx) is a protective layer that lines the luminal side of blood vessels and contains proteoglycans (core proteins with glycosaminoglycan (GAG) sidechains) that help maintain vascular permeability, and are damaged during DM. Heparanase degrades the GAG, heparan sulphate (HS), and is upregulated in DN. Heparanase inhibition and knock-down both prevent the development of DN. The objective of this study was to show that HS, specifically within the endothelial glycocalyx, is important in glomerular barrier function and that prevention of its shedding, by a novel class of heparanase inhibitor (HI), is protective in DM. 

Methods: 

Endothelial glycocalyx HS was removed in mice by intravenous injection of heparinase III, or by knock-down of Ext-1 (an HS biosynthesis enzyme) in endothelial cells using Tie2rtTA, tet-O-Cre, Ext-1fl/fl (Ext-1fl/fl) mice. A mouse model of type 2 diabetes (db/db) was used whereby HI or vehicle was given, i.p. daily, from 9-11wk of age. Mice were ringer perfused for glomerular permeability studies or Alcian blue/ glutaraldehyde perfused for electron microscopy (EM). Glomeruli were isolated from ringer perfused kidneys and apparent albumin permeability was measured in single capillaries from individual glomeruli.  Alcian blue perfused kidneys were processed for EM, imaged, and eGlx depth and percent coverage were measured using ImageJ. Urine albumin creatinine ratios (uACR) were measured at endpoint. 

Results: 

A significant reduction in glomerular endothelial glycocalyx depth and coverage was seen with heparinase III treatment and Ext-1fl/fl mice. These were associated with significant increases in glomerular albumin permeability. In diabetic mice, eGlx depth and coverage was significantly reduced and uACR was significantly increased. Diabetic mice treated with HI no longer had a significant increase in uACR and eGlx depth/coverage and glomerular albumin permeability was significantly restored when HI was given. 

Conclusion: 

We confirm that endothelial glycocalyx HS plays a direct role in the glomerular filtration barrier demonstrated by targeted HS removal. We also demonstrate that heparanase inhibition in DM, using a novel and clinically relevant inhibitor, directly enhances the glomerular endothelial glycocalyx, resulting in normalised glomerular albumin permeability. 

Lay summary: 

The glycocalyx is a sugar layer which lines all of the blood vessels in the body. In diabetes, this layer is damaged and is associated with blood vessel leakiness. In the kidney, this leads to diabetic kidney disease. Heparan sulphate is one of the main types of sugar in this layer, and it has been shown that heparanase, a protein which is able to break down heparan sulphate, is increased in diabetes. In two mouse models of heparan sulphate loss from this layer, we found that there was increased blood vessel leakiness in the kidney.  This suggests that heparan sulphate plays an important role in the glycocalyx. We then aimed to protect heparan sulphate in the glycocalyx in diabetic mice, using a new drug to block heparanase. We found that protection of the glycocalyx through use of this drug resulted in protected blood vessels and prevention of diabetic kidney disease. This work is evidence that heparan sulphate is an important component of the glycocalyx, and that preventing loss of this sugar molecule in diabetes can help to prevent the development of diabetic kidney disease.  

Biography:

My initial attraction to renal research began in the first lab I worked in as an undergraduate at the University of Michigan. Our work focused on BK polyomavirus, a ubiquitous virus which can result in polyomavirus-associated nephropathy in kidney transplant patients, increasing chances of transplant loss. I later worked as a technician in the Bristol Renal group at the University of Bristol. Here, I went on to complete my PhD focusing on therapeutically targeting the glycocalyx in the kidney, an important layer in the vasculature. I came to fully appreciate how fascinating the kidney is, and just how many people are impacted by kidney disease globally. This urgent need for renal research has kept me interested. I aim to accelerate research by understanding mechanistically how to prevent vascular dysfunction in kidney disease and applying this to other vascular beds.  Ultimately, our goal is to prevent progression of kidney disease and related cardiovascular complications for patients. Thanks to Kidney Research UK, who has funded much of the work in Bristol Renal, we are able to carry out important research which will go on to help kidney patients. Without organisations like Kidney Research UK, advancements in kidney treatments would not be possible.  

Eoin O'Sullivan

Authors and affiliations (if published): 

Eoin D O’Sullivan. David A Ferenbach.   

University of Edinburgh

Background: 

Progressive fibrosis and maladaptive organ repair results in significant morbidity and millions of premature deaths annually. Senescent cells accumulate with ageing and after injury and are implicated in organ fibrosis, but the mechanisms by which senescence influences repair are poorly understood.  

Methods: 

Two models of murine renal injury were analysed using bulk and single cell RNA sequencing to assess pathways augmented in senescent cells and the impact of the senolytic agent ABT263. Further analysis explored conserved pathways present in senescent epithelia across mice, humans, and other organ systems. Candidate molecules were identified and validated using in vitro and in vivo models of fibrotic disease. 

Results: 

We show that obstructive injury generates senescent epithelia which persist after resolution of the original injury, promote ongoing fibrosis and impede adaptive repair. Depletion of senescent cells with ABT263 reduces fibrosis in reversed ureteric obstruction and after renal ischaemia-reperfusion injury. We validate these findings in humans, showing that senescence and fibrosis persist after relieved renal obstruction. We next characterise senescent epithelia in murine renal injury using single cell RNA-Seq. We extend our classification to human kidney and liver disease and identify conserved pro-fibrotic proteins which we validate in vitro and in human disease. We demonstrate that one such molecule, Protein Disulfide Isomerase Family A Member 3 (PDIA3), is essential for TGF-beta mediated fibroblast activation. Inhibition of PDIA3 in vivo significantly reduces kidney fibrosis during ongoing renal injury.  

Conclusion: 

Inhibition of PDIA3 represents a new potential therapeutic pathway to reduce organ fibrosis after injury. Analysis of the signalling pathways of senescent epithelia connects senescence to organ fibrosis, permitting rational design of anti-fibrotic therapies.  

Lay summary: 

Our understanding of why injured and aged kidneys are more susceptible to developing progressive scarring (fibrosis) and working less well is incomplete. 

In this project we used the latest advances in cell analysis to look for novel pathways which are switched on in the injured kidney – seeking ways to treat these pathways to prevent fibrosis.  

We uncovered a range of candidate ‘bad molecules’ – and narrowed our list by looking in mice, in humans, in kidneys and in injured livers.  We identified a molecule called PDIA3 which was raised in all the settings described – and in human kidney disease. When we explored how PDIA3 works we discovered that it is an important driver of kidney fibrosis and that an experimental drug can block its activity and protect the aged and injured kidney.   

This work opens up a new avenue to prevent kidney scarring and we are currently working in collaboration with academic and pharmaceutical teams to design novel agents which can be used to move from mouse studies back to human disease. 

Biography:

Kidney diseases tend to be complex and nuanced and people living with kidney disease often have several interacting medical issues while they live with their conditions for their entire lives. These challenges mean that providing care and performing research is both intellectually rewarding but also highly impactful as you can potentially greatly enhance the quality and length of people’s lives. 

Our group has identified new molecules which can lead to renal scarring. These molecules likely drive renal fibrosis and cause progression of CKD/scarring after AKI. We have shown these pathways can be targeted successfully in mice, reducing scarring in their kidneys after injury. This could be extremely useful to patients after AKI to protect their kidneys. 

Kidney Research UK has been central to my research. The charity supported my scientific training, funded and guided the research, and built a network of passionate researchers and advocates which has allowed me to build new collaborations, enhancing research quality and generating new ideas and partnerships. 

Lucia Marinas del Rey

Authors and affiliations (if published):

Lucia Marinas del Rey^1,2,3, Krista Rombouts³, Giuseppe Mazza^3,4, Jill Norman², Reza Motallebzadeh¹

¹UCL Division of Medicine and Interventional Science
²UCL Department of Renal Medicine
³UCL Institute for Liver and Digestive Health
⁴Engitix Ltd

Background: 

Chronic kidney disease (CKD), which describes an irreversible alteration of kidney function, represents a significant worldwide healthcare burden. It can result from many different aetiologies and is one of the leading causes of mortality worldwide. Irrespective of the cause, a common feature of CKD is fibrosis in the tubulointerstitium, where persistent injury causes glomerulosclerosis, tubular atrophy, and fibrosis. The lack of effective antifibrotic therapies to stop the progression of CKD evidences the need for a better understanding of tubulointerstitial fibrosis. 

Methods: 

Tissue from normal human kidney cortex (from deceased donors) and fibrotic human kidney cortex (from explants of kidney transplants with chronic rejection) was dissected into cubes and decellularised with sodium dodecyl sulphate. Decellularised cubes were assessed by DNA content (DNeasy Kit, Qiagen), histology (haematoxylin and eosin (H&E) and picro-sirius red (PSR)) and immunohistochemistry. To develop human kidney extracellular matrix (hkECM) hydrogels, decellularised cubes were homogenised and lyophilised into a fibrous powder, which was then dissolved in 0.01M HCl to a concentration of 13 mg/ml and digested with 1 mg/ml pepsin (Sigma). hkECM (3, 4.5, and 6 mg/ml) was mixed with a nanocellulose-based material (30%) and human proximal tubular epithelial cells (HK-2 cell line) and cultured for up to 21 days. 

Results: 

Kidney tissue was successfully decellularised as shown by DNA content reduction of 97% after decellularisation. Additionally, histological analysis confirmed the elimination of nuclei by H&E staining, and lack of cellular material (yellow in PSR staining); and preservation of collagen (red; PSR). Immunohistochemistry confirmed maintenance of key ECM proteins (collagens I and IV, fibronectin, laminin α5). By decellularisation of normal kidney cortical tissue, we were able to produce a specific biomaterial derived from the tubulointerstitial extracellular matrix (hkECM). Combination of the hkECM with nanocellulose produced stable hydrogels which supported growth and differentiation of HK-2 cells. Additionally, a method for generating hydrogels from fibrotic tissue is being developed in the same manner to create models that reproduce fibrotic tissue. 

Conclusion: 

Using combinations of different renal cell types and normal and fibrotic ECM to create kidney organoids, this system has the potential to recapitulate the biomechanical and biochemical properties of the tissue and the cell-ECM interactions. Comparison of the normal and fibrotic organoids will provide insights into the role of the ECM in regulating cell differentiation and function, model tubulointerstitial fibrosis, and potentially establish a platform for drug testing. 

Lay summary: 

Chronic kidney disease (CKD), which describes an irreversible alteration of kidney function, represents a significant worldwide healthcare burden, being one of the leading causes of mortality worldwide. Irrespective of the cause, a common feature of CKD is fibrosis in the tubulointerstitium, where persistent injury causes glomerulosclerosis, tubular atrophy, and fibrosis. The lack of effective antifibrotic therapies to stop the progression of CKD evidences the need for a better understanding of tubulointerstitial fibrosis.  

The aim is to use tissue engineering to develop a 3D hydrogel model of the tubulointerstitium and study renal fibrosis. By decellularisation of normal and fibrotic kidney cortical tissue, we produced a specific biomaterial derived from the tubulointerstitial extracellular matrix (ECM) - hkECM. Combination of the hkECM with nanocellulose generated stable hydrogels which supported growth and differentiation of human proximal tubular epithelial cells. Combining different renal cell types to create kidney organoids, this system can recapitulate the biomechanical and biochemical properties of the tissue and the cell-ECM interactions. Comparison of the normal and fibrotic organoids will provide insights into the role of the ECM in regulating cell differentiation and function, model fibrosis, and potentially establish a platform for drug testing. 

Biography: 

I am dedicating my PhD at UCL to developing models of the kidney tubulointerstitium in normal and fibrotic conditions. Having graduated in biomedical engineering and done an MSc in regenerative medicine, working in tissue engineering has always been my goal. This is what drove me to move to London from Madrid, to be a part of the exciting research that organisations such as Kidney Research UK and UCL are involved in. In my two years of PhD, I have developed an understanding and appreciation for this field.  

I am attracted to the complexity of the kidney and kidney disease, and its many implications for our overall health. Since the beginning, I was very surprised that there was no effective cure, and I believe my work in establishing accurate in-vitro kidney models will enable future progress in the field. I hope that joining Kidney Research UK will give me the chance to meet like-minded people working in kidney research and establishing collaborations to contribute to the field. 

Holly Stowell-Connolly

Authors and affiliations (if published):

Holly Stowell-Connolly¹, Abigail C. Lay^1,2, Jennifer A Hurcombe¹, Mark Graham¹, and Richard J. Coward¹

¹Bristol Renal, University of Bristol
²Division of Cardiovascular Sciences, University of Manchester

Background: 

Glomerular podocytes are structurally, morphologically, and biochemically similar to neurons, despite different bodily and organ location and germ line origin. Additionally, diseases causing neuronal degeneration show associations with chronic kidney disease (CKD), as evidenced by a three-fold increase in the likelihood of developing dementia in patients with renal failure (RF). Due to such associations, we hypothesise common mechanistic pathways contributing to disease progression in both cell types, specifically in diabetes. This work aims to understand differential podocyte expression and activation of TBK1, a protein abnormally deactivated in neurons in Amyotrophic Lateral Sclerosis (ALS, aka Motor Neuron Disease).  

Methods: 

Transcriptomic and proteomic analysis determined differential renal expression of genes known to be involved in neuronal degeneration, specifically in conditions related to diabetes. Conditionally immortalized human podocytes (cihPods) were grown in basal or diabetic conditions (DC) (physiologically high concentrations of insulin, glucose, TNF-α, and IL-6), and validation of aberrant expression of TBK1 was confirmed by qRT-PCR, western blotting (WB), and immunofluorescence (IF). Importance of podocyte TBK1 expression and signalling was investigated by generating a constitutive TBK1 knock-down (KD) in using lentiviral transduction of shRNA. KD was confirmed by qRT-PCR and IF. Cell line characterization was achieved via WB and scratch assays. 

Results: 

Transcript- and proteomic analysis determined TBK1 mRNA and protein expression to be increased in human and mouse podocytes grown in DC (p<0.05). Expression is unchanged in glomerular endothelial or proximal tubular cells. IF demonstrates TBK1 expression is upregulated in DC, as well as activation indicated by at S172 phosphorylation. pTBK1 S172 translocates to the nucleus where it colocalizes with SUMO and PML, suggesting sequestration at PML-nuclear bodies in response to an insulin- and IL-6-rich environment. KD of TBK1 within cihPods results in aberrant cell growth, as demonstrated by increased cellular and nuclear area, and abnormal actin architecture. Early work indicates this is not a result of re-entry of the cell cycle. Current work will determine a role of Hippo signalling and initiation of cell death mechanisms. Additional early work indicates increased cell motility in KD cells. Current work aims to understand the response of cihPods to DC with a TBK1 KD.   

Conclusion: 

Proteins involved in neuronal degeneration can be abnormally regulated in cihPods in DC. TBK1 expression and activation is upregulated in cihPods grown in DC, with a novel nuclear sequestration in podocyte nuclei. TBK1 KD causes aberrant actin fibre growth, leading to increases in cellular and nuclear area. 

Lay summary: 

Neurodegenerative diseases, such as Alzheimer’s disease, Parkinson’s disease, and Motor Neuron Disease (ALS), occur when a specific set of cells within the brain, neurons, become injured and eventually die. Patients with dementias including Alzheimer’s disease often develop other diseases, including diabetes and chronic kidney disease (CKD). Interestingly, patients with dementia are three times as likely as healthy individuals to also develop CKD. The causes of this association are currently unknown. Injury to neurons is often a response to abnormal regulation of specific proteins. This work aims to understand how proteins involved in such injury are regulated within a type of kidney cell, the podocyte, and how diabetes can affect its regulation and function. We demonstrate podocyte presence of TBK1, known to be deactivated in some ALS patients, and show increased expression and activation in diabetes. We aim to assess the importance of TBK1 in kidney health, by removing TBK1 from podocytes and measuring changes in cell growth and function. Understanding how proteins involved in both neuron and podocyte injury may lead to the repurposing of current treatments, or the development of new therapies for both neurodegenerative and CKD patients. 

Biography:

I first found myself interested in the renal field whilst studying the kidney during my A-Levels and my undergraduate degree, and so when applying for a laboratory experience it was my first choice! During this time, my interest in the field grew further, initiating my desire to continue my renal research with generous funding from Kidney Research UK. My current work is quite novel, and I hope that it can provide advances in patient treatments for, not just kidney disease, but also neurodegenerative diseases. Not only has Kidney Research UK facilitated this research, but their funding has also allowed me to continue in a field I greatly enjoy. 

David Ferenbach

Authors and affiliations (if published): 

David Ferenbach

Background: 

Progressive fibrosis is a feature of aging and chronic tissue injury in multiple organs including the kidney and heart. Gli1+ mesenchymal stem cells are a major source of activated fibroblasts in multiple organs but the links between injury, inflammation and Gli1+ stem cell expansion and tissue fibrosis remain incompletely understood. Here we show that leukocyte derived tumour necrosis factor alpha (TNFa) promotes Gli1+ stem cell proliferation and cardio-renal fibrosis via downstream induction and release of Indian Hedgehog (IHH) from renal epithelia. 

Methods: 

Single cell RNA sequencing was performed on healthy young, healthy aged and young fibrotic kidneys from mice. Pharmacological and conditional genetic blockade was used to determine the key molecules generated from injured and aged kidneys, and their impact on cardiac and renal fibrosis assessed in experimental mice and in human kidney disease. 

Results: 

Using single cell RNA sequencing of aged and fibrotic kidneys, we identify an ‘inflammatory’ proximal tubular epithelia (iPT) population expressing high levels of ubiquitin D (UBD) responsible for TNFa/NFkB induced IHH production in vivo. TNFa induces UBD expression in human proximal tubular cells in vitro and in vivo in experimental murine and human renal disease and ageing. Ubd+ iPT derived IHH activates canonical Hedgehog signalling in Gli1+ progenitors, inducing their activation and proliferation with resultant fibrosis in the injured and ageing kidney and heart. Of note, this occurs independent of blood pressure and renal functional change and is inhibited in mice by selective genetic Ihh deletion from Pax8 expressing renal epithelia, and by pharmacological blockade of TNFa, NFkB, Hedgehog or Gli signalling.   Increased levels of circulating IHH associate with more rapid loss of renal function and higher rates of cardiovascular disease in patients with chronic kidney disease.   

Conclusion: 

Indian Hedgehog is the upstream ligand connecting leukocyte activation to Gli1+ mesenchymal stem cell expansion and fibrosis. These studies provide a mechanistic basis for translational studies in humans to inhibit the early components of signalling (via TNFa inhibitors), and for the design of novel agents to selectively block the fibrotic effects of IHH upon the kidney and heart. 

Lay summary: 

Our understanding of why injured and aged kidneys are more susceptible to developing progressive scarring (fibrosis) and why kidney disease promotes heart problems remains poor. 

In this project we use the latest advances in cell analysis to identify a novel sub-type of kidney cell present in injured and aged kidneys. We show that these cells are the result of activation by white blood cells within the kidney (as is known to occur after injury and ageing).  Of key importance – these cells also release a molecule called Indian Hedgehog (IHH) which is an important driver of fibrosis in the kidney and heart. Testing human samples from another Kidney Research UK funded study, we show that human patients with higher levels of IHH develop further kidney scarring and cardiac problems more rapidly than those with low levels. By blocking the release of this molecule, we demonstrate that we can protect against these processes. 

On the basis of this work (and published evidence from other conditions that blocking TNFa is safe and helps prevent deteriorating kidney function) we propose that human trials should be undertaken to test the effects of TNFa blockers in chronic kidney disease (to prevent kidney and cardiac disease) and in dialysis patients (seeking to prevent cardiac problems). 

Biography: 

David Ferenbach graduated in medicine from the University of Edinburgh and, after training posts in Edinburgh and Glasgow, completed his PhD in the Centre for Inflammation Research in Edinburgh.  Here he developed a research interest in the mechanisms driving accelerated fibrosis in injured and aged kidneys funded by a clinical training fellowship from Kidney Research UK.  He pursued this goal further during his Wellcome Trust intermediate fellowship in the Bonventre Laboratory of Harvard Medical School.  Today, his laboratory in Edinburgh is focused on understanding the role played by senescent epithelia in driving kidney scarring – with the aim of developing new treatments for human fibrotic disease.

As a clinically practicing nephrologist I am constantly reminded of both the huge advances we have made in treating kidney disease – but also by the major problems that remain unsolved: 

• Why are elderly people at increased risk of acute kidney injury and longer-term chronic kidney disease?   
• How can we prevent kidney fibrosis from progressing?  
• How could we best prevent our patients from suffering from hugely increased rates of cardiovascular disease and death? 

My laboratory remains focused on advancing our understanding of the questions above, with the goal of translating this to novel treatments for our patients.

Over the past two years we have published exciting work delineating how previous kidney injury and ageing leads to dysfunctional, “senescent” cells within the kidney (with two papers published/in press in Science Translational Medicine and another in JCI Insight).  This work revealed novel targets for anti-fibrotic therapies – which we have recently reached agreement with pharmaceutical companies to generate and validate novel therapies designed to preserve kidney function and prevent fibrosis in the aftermath of injury.  

Without the backing of Kidney Research UK I would not be in renal research today - the charity has support me throughout the last 15+ years: at the stage of my PhD, awarding my lab its first project grant and now, with two additional innovation awards.  I am immensely grateful to the entire Kidney Research UK team for their support. 

Serena MacMillan, PhD student at The University of Cambridge

Authors and affiliations (if published): 

Serena MacMillan, Sarah A Hosgood, Michael Nicholson.  

Department of Surgery, University of Cambridge, UK.  

This work has been accepted for publication as a Short Report for the British Journal of Surgery. 

Background: 

A major restriction to transplantation is the requirement for ABO blood group compatibility between donor and recipient. In this study, we have used an a-galactosidase from Bacteroides fragilis to enzymatically remove type B blood group antigens from human kidneys using ex vivo normothermic machine perfusion (NMP) to overcome the ABO barrier in kidney transplantation.  

Methods: 

Human donor kidneys rejected for transplantation and offered for research were used in this study with approval by the National Research Ethics committee and Research and Development office (NRES: 15/NE/0408). An a-galactosidase (GH110B) from B. fragilis was used to remove type B blood group antigens from fixed tissue from five type B donor kidneys, quantified with immunofluorescence staining of blood group B and H antigens on the vascular endothelium. Three further human kidneys of blood group B then underwent five hours acellular NMP supplemented with 2.5mg/ml of GH110B alongside one untreated control kidney and serial biopsies were stained and quantified for antigen removal. 

Results: 

In all biopsies examined, B antigen expression was restricted to peritubular capillaries. In fixed tissue, GH110B removed up to 99% of endothelial blood group B antigens after 1hr of incubation. In three whole kidneys, between 67-94% of B antigens were removed after 5hrs of acellular NMP. 

Conclusion: 

For the first time, we have shown that blood group antigens can be successfully removed from whole human kidneys using NMP. This proof-of-principle work paves the way for future development and clinical application to increase the number of ABO-compatible grafts in transplantation. 

Lay summary: 

All people have one of four bloods groups: O, A, B or AB and this is called their ABO blood type. Kidney transplants cannot be performed unless the donor and the recipient have compatible ABO types. If the blood groups don’t match, then the kidney transplant can be rejected immediately. Importantly, anyone can receive a kidney that is blood type O and is therefore called the universal donor. Unfortunately, less than half of all donated kidneys are type O.  

We are researching a new way of changing the blood group of a kidney. Blood type is determined by A or B markers that line kidney blood vessels. Blood group O kidneys do not have either A or B markers or ‘antigens’. Enzymes that work as ‘biological scissors’ can remove A and B antigens from cell surfaces, effectively making cells blood group O. We have now applied this idea to human kidneys that have been turned down for transplantation and donated for research. In this work, we have removed between 67-94% of blood group B antigens from three blood group B kidneys. This research could transform the way that kidney transplantation is delivered throughout the world. 

Biography:

When deciding to pursue a PhD, I was looking for research that was translational and had close ties with clinical work. Everything fell into place when I discovered the amazing work being undertaken in kidney transplantation research. Being able to feel the momentum behind life-changing renal research drives my work and provides real satisfaction in my day-to-day lab work on blood group conversion of human kidneys. 

My work is at an exciting stage now we have shown the first proof-of-principle work of converting human kidneys from type A or B blood groups to a universally transplantable type. The research has the chance to make a real change to organ allocation for kidney transplantation and to know that it may one day improve outcomes for those on the waiting list is an amazing boost. 

Kidney Research UK has funded my PhD and so I am incredibly grateful to the charity for giving me the opportunityy to pursue this work. The charity has also provided amazing exposure for the research and the field of kidney transplantation, which is so critical for public engagement with renal research. 

Joyce Popoola

Authors and affiliations (if published):

Joyce Popoola¹, Suhaylah Bauhadoor¹, Jonathan Bartley²

¹Consultant Nephrologist, Young Adult Worker Department of Nephrology and Transplantation, St George’s University Hospitals NHS Foundation Trust, London
²Patient Support and Advocacy Worker Kidney Care UK

Background: 

The population of young adults (16-29 years) with renal disease is increasing partly due to a rising number transferring from the paediatric units and increased life expectancy. Unfortunately, they are also at risk of significant co-morbidity and early mortality compared to their contemporaries. Young adults often struggle to understand their conditions and adherence is most challenging in this age group. We have carried out local surveys exploring the needs of young adults from their perspective. Overwhelmingly they highlight; lack of peer support and information on their condition not presented in a readily accessible generation friendly format. 

Methods and results:   

We are developing a bespoke tool “My Nephros” for young adults on renal disease and transplantation providing targeted succinct answers to their healthcare queries. Responses to their most, frequently asked questions (FAQs) are presented using interactive modern technology in a contemporary fashion. Short videos and audios as sound bites are being used for responses. This is being achieved with the direct input of representatives from our young adult population, young adult worker, health advisor and psychologist. The responses are scientifically sound and formulated in a Millennial and Generation Z accessible fashion.   

Conclusion:   

Patients and carers nowadays are keen to do their own research in relation to matters related to their healthcare. The usual place for the young adults to do this is via internet searches and social media platforms. More time and motivation may be required to stimulate changes in patient behaviours related to educational opportunities. We however present a tool with potential to be used in helping patients’ values guide healthcare acceptance.  

Lay summary: 

Here we present the use of a tool for Young Adults, “My Nephros” to help them learn more about their kidney disease or transplant. It is based on commonly asked questions by young adults in relation to understanding and managing their condition and will be accessible on the internet via search engines and social media.  

Empowering young adults helping them understand their condition may help improve their self-care. 

Biography:

Joyce Popoola is a renal consultant at St George’s University Hospital NHS Foundation Trust, an honorary senior lecturer and clinical subdean, St George’s University London.

Renal medicine is a relatively new specialty, and yet affects at least 10% of the world’s population including young people. In the absence of targeted intervention this can only get worse resulting in devastation of individuals, families, and communities. Self-actualisation and global economies are particularly impacted when the youth are affected.  

Laboratory, clinical translational and epidemiological studies form the bulk of research. Joyce’s team are additionally interested in researching the development and embedding of relevant trusted decision-making educational tools. She believes these are essential to maximising and ensuring lasting research footprints, particularly among younger patients who tend to ‘’do their own research’’. 

Joyce had interest in innovative practice from her early years in training. Kidney Research UK gave an amazing head start by awarding her a fellowship enabling research into transplantation. This opened a new world to her in research, education and cutting-edge clinical care in nephrology and transplantation. An international transplant fellowship enabled post-doctoral studies in Boston. She returned to the UK to take up the role of lead transplant physician and later of young adult care.