Adipose tissue-derived mesenchymal stromal cells for treating chronic kidney disease: A pilot study assessing safety and clinical feasibility

Clinical Prospect of Mesenchymal Stromal/Stem Cell-Derived Extracellular Vesicles in Kidney Disease: Challenges and the Way Forward

Kidney disease is a growing public health problem worldwide, including both acute and chronic forms. Existing therapies for kidney disease target various pathogenic mechanisms; however, these therapies only slow down the progression of the disease rather than offering a cure. One of the potential and emerging approaches for the treatment of kidney disease is mesenchymal stromal/stem cell (MSC) therapy, shown to have beneficial effects in preclinical studies. In addition, extracellular vesicles (EVs) released by MSCs became a potent cell-free therapy option in various preclinical models of kidney disease due to their regenerative, anti-inflammatory, and immunomodulatory properties. However, there are scarce clinical data available regarding the use of MSC-EVs in kidney pathologies. This review article provides an outline of the renoprotective effects of MSC-EVs in different preclinical models of kidney disease. It offers a comprehensive analysis of possible mechanisms of action of MSC-EVs with an emphasis on kidney disease. Finally, on the journey toward the implementation of MSC-EVs into clinical practice, we highlight the need to establish standardized methods for the characterization of an EV-based product and investigate the adequate dosing, safety, and efficacy of MSC-EVs application, as well as the development of suitable potency assays.

Chronic Kidney Disease: Challenges in Translational Medicine

Chronic kidney disease (CKD) has long been recognized as a state of progressive decline in renal function. Morbidity and mortality are well correlated to the stage of renal function decline. Approximately one million deaths are estimated to be related to CKD worldwide. They are mostly associated with cardiovascular disease as a result of concurrent hypertension, accelerated atherosclerosis, and volume overload. Even with the best current treatment, disease progression is the general rule with a small fraction who reach CKD stage 5 requiring kidney transplantation or dialysis. Transplant patients show substantial reductions in mortality and cardiovascular events, as well as improvements in quality of life. However, the capacity of health systems to deliver kidney transplantation varies worldwide with worse indicators in low-income countries. Consequently, exploring novel and better therapeutic options for CKD is mandatory. Cell-based therapy is a promising strategy for treating CKD in preclinical models, and several clinical trials involving kidney disease exhibit a favorable safety profile. This chapter aims to provide an overview of CKD and the recent results of clinical trials of cell therapy in kidney diseases.

Can mobilization of bone marrow stem cells be an alternative regenerative therapy to stem cell injection in a rat model of chronic kidney disease?

Chronic kidney disease (CKD) is a priority health problem affecting 36% of Egyptians. Adipose-derived mesenchymal stem cells (ADMSCs) have multidifferentiation capacity and the ability to restore several types of cells including damaged renal cells. Granulocyte colony-stimulating factor (G-CSF) is known to mobilize hematopoietic stem cells from bone marrow to the peripheral circulation. The aim of this study was to compare the effect of endogenous CD34+ cells mobilization and exogenous ADMSCs administration in the treatment of a rat model of adriamycin (ADR)-induced CKD. A total of 48 male albino rats of the local strain (200 ± 50 g) were equally divided into four groups: control negative, ADR (control positive), ADMSCs group, and G-CSF group. Six rats from each group were sacrificed after 4 weeks and the other 6 after 12 weeks. Renal function was assessed frequently by measuring serum creatinine, albumin, urea, 24-h urinary protein level, and hemoglobin level throughout the study. Oxidative stress markers malondialdehyde (MDA) and total antioxidant (TAO) were measured on day 28. CD-34+ cell percentage was measured on day 9. After the sacrification of the rats, kidneys were removed for histopathological assessment. Results revealed that both ADMSCs and G-CSF significantly improved serum creatinine, albumin, urea, 24-h urinary protein level, and histopathological damage score, with the G-CSF-treated group showing better improvement in 24-h urinary protein level, serum albumin, and histopathological damage score compared with ADMSCs-treated group. The G-CSF group also had significantly higher levels of CD34+ cells. Oxidative stress markers (MDA and TAO) levels were significantly improved with both therapies. We conclude that mobilization of endogenous hematopoietic stem cells by G-CSF is more effective than exogenously injected ADMSCs in protecting the kidneys against AD-induced toxicity.

Protocol for a Phase 1, Open-Label, Multiple-Center, Dose-Escalation Study to Evaluate the Safety and Tolerability of ADR-001 in the Treatment of Immunoglobulin A Nephropathy

Introduction

Immunoglobulin A (IgA) nephropathy is a disease that presents with urinary symptoms such as glomerular hematuria and urinary protein positivity, with predominant deposition of IgA in the mesangial region of the glomerulus. Corticosteroids are mainly used for treatment; however, infection is a serious adverse event, and evidence regarding therapeutic efficacy is insufficient, thus new treatments are strongly desired. Mesenchymal stem cells (MSCs) contribute to the amelioration of inflammation and recovery of organ function in inflammatory environments by converting the character of leukocytes from inflammatory to anti-inflammatory and inducing the proliferation and differentiation of organ component cells, respectively. These properties of MSCs have led to their clinical application in various inflammatory diseases, but this study is the first clinical trial of MSCs for refractory glomerulonephritis in the world. This study is registered and assigned the number, jRCT2043200002 and NCT04342325.

Methods

This will be a phase 1, open-label, multiple-center, dose-escalation study of adult patients with refractory IgA nephropathy resistant to or difficult to treat with existing therapies. ADR-001 will be administered intravenously to from three to six patients at a dose of 1 × 108 cells once in the first cohort and to six patients twice at 2-week intervals in the second cohort, and observation will continue until 52 weeks. The primary endpoint will be the evaluation of adverse events up to 6 weeks after the start of ADR-001 administration. Secondary endpoints will be the respective percentages of patients with adverse events, clinical remission, partial remission, remission of urine protein, remission of hematuria, time to remission, changes in urine protein, hematuria, and estimated glomerular filtration rate.

Results

Following the administration of ADR-001 to patients with IgA nephropathy, the respective percentages of patients with adverse events, asymptomatic pulmonary emboli, clinical remission, partial remission, urine protein remission, hematuria remission, their time to remission, changes in urine protein, hematuria, and glomerular filtration rate will be determined.

Conclusion

This study will evaluate the safety and tolerability of ADR-001 and confirm its therapeutic efficacy in adult patients with refractory IgA nephropathy.

Adipose-derived stem cell and their extracellular vesicles ameliorates immune function, and cardiac markers in experimental model of cardiorenal syndrome type III: TNF-α, IFN-γ and IL-10 cytokine production and their correlation with genotype

Cardio-renal syndrome (CRS) denotes the convergence of heart-kidney interactions across several mechanisms. The current study is conducted to evaluate the anti-inflammatory role of adipose tissue-derived stem cells (ASCs) versus adipose stem cell-derived extracellular vesicles (ADSCs-EVs) in experimental model of cardiorenal syndrome type III. The study was conducted on 50 male rats that were equally divided to: group I (control group); Group II (experimental cardiorenal syndrome group) which induced by right renal artery ligation (ICRSIII); Group III (Sham-operated control group) which underwent surgical incision without renal artery ligation; Group IV (ICRSIII which received ADSCs-extracellular vesicles (ADSCs-EVs); Group V (ICRSIII which received adipose tissue stem cells (ASCs). Assessment of pro-inflammatory cytokines; IL-10, IL-1α, IL-6, IL-1 β, IFN-γ, NF-α and their mRNA gene expression quantitation, (NGAL), and brain natriuretic peptide (BNP) as markers of cardiac dysfunction, as well as histopathological examination of renal tissue was examined by H& E, Masson trichrome and periodic acid-Schiff stains (PAS). The ICRS group exhibited significant acute tubular injury with tubular dilation, loss of brush borders, epithelial flattening, and occasional sloughed cells in lumen. Use of either ADSCs-EVs or ASCs significantly ameliorated the histological findings of tubular injury. Proinflammatory cytokines, BNP and NGAL were significantly elevated in ICRSIII group as compared to all other studied groups. Administration of ADSCs-EVs or ASCs led to significant decrease in all proinflammatory cytokines as well as BNP and NGAL levels with no significant difference between them. In conclusion, ADSCs-EXs and ASCs exhibited significant repairing effects in experimental-induced cardiorenal syndrome type III as evidenced by amelioration of histological findings of tubular injury, anti-inflammatory effects, and the significant decrease in markers of cardiac dysfunction. ADSC-EVs reprogramed injured cardiac cells by activating regenerative processes.

Effects of intravenous administration of allogeneic mesenchymal stromal cells, derived from adipose tissue, in five dogs with chronic kidney disease

ABSTRACT This study aimed to evaluate the safety of allogeneic adipose-derived mesenchymal stromal cell (aASC) treatment in dogs with chronic kidney disease (CKD) at the time of infusions and during the 120-day follow-up after the last infusion. Five dogs with CKD received three intravenous infusions of approximately 1×106?10% of aASCs per kilogram of body weight at 21-day intervals. Clinical and laboratory evaluations were performed at the time of each treatment and at 30 and 120 days after the last infusion. Adverse effects of the treatment were assessed using clinical observations, laboratory analyses, and owners’ answers about their dog’s behavior after infusions and during follow-up. The investigated animals did not present any adverse effects immediately after infusion or during the follow-up after the last infusion according to clinical and laboratory observations, as well as the dog owner’s descriptions. One treated animal showed a reduction in creatinine, from 3.5mg/dL to 2.4mg/dL from day 0 to day 153, gained 100g of body weight, and improved disposition. The study results demonstrate that aASC therapy is safe for dogs with CKD; however, further studies are needed to investigate these promising results.

Current advances of stem cell-based therapy for kidney diseases

Kidney diseases are a prevalent health problem around the world. Multidrug therapy used in the current routine treatment for kidney diseases can only delay disease progression. None of these drugs or treatments can reverse the progression to an end-stage of the disease. Therefore, it is crucial to explore novel therapeutics to improve patients’ quality of life and possibly cure, reverse, or alleviate the kidney disease. Stem cells have promising potentials as a form of regenerative medicine for kidney diseases due to their unlimited replication and their ability to differentiate into kidney cells in vitro. Mounting evidences from the administration of stem cells in an experimental kidney disease model suggested that stem cell-based therapy has therapeutic or renoprotective effects to attenuate kidney damage while improving the function and structure of both glomerular and tubular compartments. This review summarises the current stem cell-based therapeutic approaches to treat kidney diseases, including the various cell sources, animal models or in vitro studies. The challenges of progressing from proof-of-principle in the laboratory to widespread clinical application and the human clinical trial outcomes reported to date are also highlighted. The success of cell-based therapy could widen the scope of regenerative medicine in the future.

Harnessing the Physiological Functions of Cellular Prion Protein in the Kidneys: Applications for Treating Renal Diseases

A cellular prion protein (PrP^C) is a ubiquitous cell surface glycoprotein, and its physiological functions have been receiving increased attention. Endogenous PrP^C is present in various kidney tissues and undergoes glomerular filtration. In prion diseases, abnormal prion proteins are found to accumulate in renal tissues and filtered into urine. Urinary prion protein could serve as a diagnostic biomarker. PrP^C plays a role in cellular signaling pathways, reno-protective effects, and kidney iron uptake. PrP^C signaling affects mitochondrial function via the ERK pathway and is affected by the regulatory influence of microRNAs, small molecules, and signaling proteins. Targeting PrP^C in acute and chronic kidney disease could help improve iron homeostasis, ameliorate damage from ischemia/reperfusion injury, and enhance the efficacy of mesenchymal stem/stromal cell or extracellular vesicle-based therapeutic strategies. PrP^C may also be under the influence of BMP/Smad signaling and affect the progression of TGF-β-related renal fibrosis. PrP^C conveys TNF-α resistance in some renal cancers, and therefore, the coadministration of anti-PrP^C antibodies improves chemotherapy. PrP^C can be used to design antibody-drug conjugates, aptamer-drug conjugates, and customized tissue inhibitors of metalloproteinases to suppress cancer. With preclinical studies demonstrating promising results, further research on PrP^C in the kidney may lead to innovative PrP^C-based therapeutic strategies for renal disease.

Mesenchymal Stem Cell Therapy for Diabetic Kidney Disease: A Review of the Studies Using Syngeneic, Autologous, Allogeneic, and Xenogeneic Cells

Diabetic kidney disease (DKD) is a microvascular complication of diabetes mellitus (DM) and comprises multifactorial pathophysiologic mechanisms. Despite current treatment, around 30-40% of individuals with type 1 and type 2 DM (DM1 and DM2) have progressive DKD, which is the most common cause of end-stage chronic kidney disease worldwide. Mesenchymal stem cell- (MSC-) based therapy has important biological and therapeutic implications for curtailing DKD progression. As a chronic disease, DM may impair MSC microenvironment, but there is compelling evidence that MSC derived from DM1 individuals maintain their cardinal properties, such as potency, secretion of trophic factors, and modulation of immune cells, so that both autologous and allogeneic MSCs are safe and effective. Conversely, MSCs derived from DM2 individuals are usually dysfunctional, exhibiting higher rates of senescence and apoptosis and a decrease in clonogenicity, proliferation, and angiogenesis potential. Therefore, more studies in humans are needed to reach a conclusion if autologous MSCs from DM2 individuals are effective for treatment of DM-related complications. Importantly, the bench to bedside pathway has been constructed in the last decade for assessing the therapeutic potential of MSCs in the DM setting. Laboratory research set the basis for establishing further translation research including preclinical development and proof of concept in model systems. Phase I clinical trials have evaluated the safety profile of MSC-based therapy in humans, and phase II clinical trials (proof of concept in trial participants) still need to answer important questions for treating DKD, yet metabolic control has already been documented. Therefore, randomized and controlled trials considering the source, optimal cell number, and route of delivery in DM patients are further required to advance MSC-based therapy. Future directions include strategies to reduce MSC heterogeneity, standardized protocols for isolation and expansion of those cells, and the development of well-designed large-scale trials to show significant efficacy during a long follow-up, mainly in individuals with DKD.

Stem cells: a potential treatment option for kidney diseases

The prevalence of kidney diseases is emerging as a public health problem. Stem cells (SCs), currently considered as a promising tool for therapeutic application, have aroused considerable interest and expectations. With self-renewal capabilities and great potential for proliferation and differentiation, stem cell therapy opens new avenues for the development of renal function and structural repair in kidney diseases. Mounting evidence suggests that stem cells exert a therapeutic effect mainly by replacing damaged tissues and paracrine pathways. The benefits of various types of SCs in acute kidney disease and chronic kidney disease have been demonstrated in preclinical studies, and preliminary results of clinical trials present its safety and tolerability. This review will focus on the stem cell-based therapy approaches for the treatment of kidney diseases, including various cell sources used, possible mechanisms involved, and outcomes that are generated so far, along with prospects and challenges in clinical application.