Therapeutic potential of mesenchymal stem cells in acute kidney injury is affected by administration timing

All-trans retinoic acid pretreatment of mesenchymal stem cells enhances the therapeutic effect on acute kidney injury

A promising new therapy option for acute kidney injury (AKI) is mesenchymal stem cells (MSCs). However, there are several limitations to the use of MSCs, such as low rates of survival, limited homing capacity, and unclear differentiation. In search of better therapeutic strategies, we explored all-trans retinoic acid (ATRA) pretreatment of MSCs to observe whether it could improve the therapeutic efficacy of AKI. We established a renal ischemia/reperfusion injury model and treated mice with ATRA-pretreated MSCs via tail vein injection. We found that AKI mice treated with ATRA-MSCs significantly improved renal function compared with DMSO-MSCs treatment. RNA sequencing screened that hyaluronic acid (HA) production from MSCs promoted by ATRA. Further validation by chromatin immunoprecipitation experiments verified that retinoic acid receptor RARα/RXRγ was a potential transcription factor for hyaluronic acid synthase 2. Additionally, an in vitro hypoxia/reoxygenation model was established using human proximal tubular epithelial cells (HK-2). After co-culturing HK-2 cells with ATRA-pretreated MSCs, we observed that HA binds to cluster determinant 44 (CD44) and activates the PI3K/AKT pathway, which enhances the anti-inflammatory, anti-apoptotic, and proliferative repair effects of MSCs in AKI. Inhibition of the HA/CD44 axis effectively reverses the renal repair effect of ATRA-pretreated MSCs. Taken together, our study suggests that ATRA pretreatment promotes HA production by MSCs and activates the PI3K/AKT pathway in renal tubular epithelial cells, thereby enhancing the efficacy of MSCs against AKI.

Delivery of Mesenchymal Stem Cells during Hypothermic Machine Perfusion in a Translational Kidney Perfusion Study

In transplantation, hypothermic machine perfusion (HMP) has been shown to be superior to static cold storage (SCS) in terms of functional outcomes. Ex vivo machine perfusion offers the possibility to deliver drugs or other active substances, such as Mesenchymal Stem Cells (MSCs), directly into an organ without affecting the recipient. MSCs are multipotent, self-renewing cells with tissue-repair capacities, and their application to ameliorate ischemia- reperfusion injury (IRI) is being investigated in several preclinical and clinical studies. The aim of this study was to introduce MSCs into a translational model of hypothermic machine perfusion and to test the efficiency and feasibility of this method. Methods: three rodent kidneys, six porcine kidneys and three human kidneys underwent HMP with 1-5 × 106 labelled MSCs within respective perfusates. Only porcine kidneys were compared to a control group of 6 kidneys undergoing HMP without MSCs, followed by mimicked reperfusion with whole blood at 37 °C for 2 h for all 12 kidneys. Reperfusion perfusate samples were analyzed for levels of NGAL and IL-β by ELISA. Functional parameters, including urinary output, oxygen consumption and creatinine clearance, were compared and found to be similar between the MSC treatment group and the control group in the porcine model. IL-1β levels were higher in perfusate and urine samples in the MSC group, with a median of 285.3 ng/mL (IQR 224.3-407.8 ng/mL) vs. 209.2 ng/mL (IQR 174.9-220.1), p = 0.51 and 105.3 ng/mL (IQR 71.03-164.7 ng/mL) vs. 307.7 ng/mL (IQR 190.9-349.6 ng/mL), p = 0.16, respectively. MSCs could be traced within the kidneys in all models using widefield microscopy after HMP. The application of Mesenchymal Stem Cells in an ex vivo hypothermic machine perfusion setting is feasible, and MSCs can be delivered into the kidney grafts during HMP. Functional parameters during mimicked reperfusion were not altered in treated kidney grafts. Changes in levels of IL-1β suggest that MSCs might have an effect on the kidney grafts, and whether this leads to a positive or a negative outcome on IRI in transplantation needs to be determined in further experiments.

Possible Underlying Mechanisms for the Renoprotective Effect of Retinoic Acid-Pretreated Wharton's Jelly Mesenchymal Stem Cells against Renal Ischemia/Reperfusion Injury

Objectives: The current work investigated the effect of Wharton jelly mesenchymal stem cells (WJ-MSCs) pretreated with all-trans-retinoic acid (ATRA) on renal ischemia in rats and the possible role of oxidative stress, apoptotic and Wnt/β-Catenin signaling pathways, and inflammatory cytokines in their effects. Methods: The study included 90 male Sprague Dawley rats that were allocated to five groups (n = 18 rats): (I) Sham-operated group (right nephrectomy was performed); (II) Ischemia/reperfusion injury (IRI) group, a sham group with 45-min renal ischemia on the left kidney; (III) ATRA group, an ischemic group with an intravenous (i.v.) administration of ATRA 10 µM, 10 min post-surgery); (IV) WJ-MSCs group, an IRI group with an i.v. administration of 150 µL containing 7 × 106 WJ-MSCs, 10 min post-surgery; (V) WJ-MSCs + ATRA group, an IRI group with an i.v. administration of 150 µL of 7 × 106 WJ-MSCs pretreated with 10 µM ATRA. At the end of the experiments, serum creatinine, BUN micro-albuminuria (MAU), urinary protein, markers of redox state in the left kidney (MDA, CAT, SOD, and GSH), and the expression of Bax, IL-6, HIF-1α, Wnt7B, and β-catenin genes at the level of mRNA as well as for immunohistochemistry for NFkB and β-Catenin markers were analyzed. Results: The current study found that 45-min of renal ischemia resulted in significant impairment of kidney function (evidenced by the increase in serum creatinine, BUN, and urinary proteins) and deterioration of the kidney morphology, which was associated with a significant increase in redox state (evidenced by an increase in MDA and a decrease in GSH, SOD, and CAT), and a significant increase in inflammatory and apoptotic processes (evidenced by an increase in Bax and IL-6, NFkB, Wnt7B, β-catenin and HIF-1α) in kidney tissues (p < 0.05). On the other hand, treatment with ATRA, WJ-MSCs, or a combination of both, caused significant improvement in kidney function and morphology, which was associated with significant attenuation of oxidative stress, apoptotic markers, and inflammatory cytokines (IL6 and NFkB) with the upregulation of HIF-1α and β-catenin in kidney tissues (p < 0.05). Moreover, the renoprotective effect of WJ-MSCs pretreated with ATRA was more potent than WJ-MSCs alone. Conclusions: It is concluded that preconditioning of WJ-MSCs with ATRA may enhance their renoprotective effect. This effect could be due to the upregulation of the beta-catenin/Wnt pathway and attenuation of apoptosis, inflammation, and oxidative stress.

When Origin Matters: Properties of Mesenchymal Stromal Cells From Different Sources for Clinical Translation in Kidney Disease

Advanced therapy medicinal products (ATMPs) offer new prospects to improve the treatment of conditions with unmet medical needs. Kidney diseases are a current major health concern with an increasing global prevalence. Chronic renal failure appears after many years of impairment, which opens a temporary window to apply novel therapeutic approaches to delay or halt disease progression. The immunomodulatory, anti-inflammatory, and pro-regenerative properties of mesenchymal stromal cells (MSCs) have sparked interest for their use in cell-based regenerative therapies. Currently, several early-phase clinical trials have been completed and many are ongoing to explore MSC safety and efficacy in a wide range of nephropathies. However, one of the current roadblocks to the clinical translation of MSC therapies relates to the lack of standardization and harmonization of MSC manufacturing protocols, which currently hinders inter-study comparability. Studies have shown that cell culture processing variables can have significant effects on MSC phenotype and functionality, and these are highly variable across laboratories. In addition, heterogeneity within MSC populations is another obstacle. Furthermore, MSCs may be isolated from several sources which adds another variable to the comparative assessment of outcomes. There is now a growing body of literature highlighting unique and distinctive properties of MSCs according to the tissue origin, and that characteristics such as donor, age, sex and underlying medical conditions may alter the therapeutic effect of MSCs. These variables must be taken into consideration when developing a cell therapy product. Having an optimal scale-up strategy for MSC manufacturing is critical for ensuring product quality while minimizing costs and time of production, as well as avoiding potential risks. Ideally, optimal scale-up strategies must be carefully considered and identified during the early stages of development, as making changes later in the bioprocess workflow will require re-optimization and validation, which may have a significant long-term impact on the cost of the therapy. This article provides a summary of important cell culture processing variables to consider in the scale-up of MSC manufacturing as well as giving a comprehensive review of tissue of origin-specific biological characteristics of MSCs and their use in current clinical trials in a range of renal pathologies.

Administration of Donor-Derived Nonexpanded Adipose Stromal Vascular Fraction Attenuates Ischemia-Reperfusion Injury in Donation After Cardiac Death Rat Renal Transplantation

Donation after cardiac death (DCD) has become a potential source for transplantation organs. However, ischemia/reperfusion injury (IRI) induced by cardiac arrest has limited the use of DCD organs. Stromal vascular fraction (SVF) without the culturing step has been proposed as a safer and easier source for stem cell therapy, which has emerged as an attractive technology that could facilitate the recovery of renal function and structure from acute kidney injury induced by IRI after DCD renal transplantation. In this study, freshly isolated donor-derived SVF was identified and then delivered intra-arterially into the grafts in DCD rat renal transplantation. Administration of freshly isolated donor-derived SVF could significantly alleviate the IRI of renal grafts and enhance graft reparation by promoting graft cell proliferation and microvascularization in DCD renal transplantation. Moreover, results revealed that the oxidative stress in grafts was significantly alleviated with SVF treatment, and this might be attributed to the overexpression of antioxidative molecules including nuclear factor erythroid-related factor 2, superoxide dismutase-1, and heme oxygenase-1. In conclusion, our study demonstrated that the administration of freshly isolated donor-derived nonexpanded adipose SVF could attenuate IRI and protect the grafts after DCD rat renal transplantation.

Mesenchymal Stromal Cell Uses for Acute Kidney Injury-Current Available Data and Future Perspectives: A Mini-Review

There is growing evidence concerning the potential use of mesenchymal stromal cells (MSCs) for different tissue injuries. Initially, the intended physiological use of MSCs was due to their ability to differentiate and replace damaged cells. However, MSCs have multiple effects, including being able to significantly modulate immunological responses. MSCs are currently being tested for neurodegenerative diseases, graft vs. host disease, kidney injury, and other chronic unremitting tissue damage. Using MSCs in acute tissue damage is only now being studied. Acute kidney injury (AKI) is a common cause of morbidity and mortality. After the primary insult, overactivation of the immune system culminates in additional secondary potentially permanent kidney damage. MSCs have the potential to ameliorate the secondary damage, and recent studies have shed important light on their mechanisms of action. This article summarizes the basics of MSCs therapy, the newly discovered mechanisms of action, and their potential application in the setting of AKI.

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.

Recent Updates on Mesenchymal Stem Cell Based Therapy for Acute Renal Failure

Acute kidney injury, formerly known as acute renal failure, is a pathological condition in which ischemia or toxic damage contributes to the loss of renal proximal tubule epithelial cells. Pathophysiological events such as oxidative stress, mitochondrial dysfunction, and direct renal tubular epithelial cells toxicity are responsible for the progression of the disease. This devastating decline in renal function affects mostly patients in the intensive care units and requires costly and invasive treatments such as dialysis and organ transplant. Fortunately, recent therapies such as the use of mesenchymal stem cells (MSCs) were proven to be effective in ameliorating renal failure via paracrine and immunomodulatory mechanisms. These fibroblast-like adult stem cells that differentiate multilineagely can be isolated from dental pulps, umbilical cords, amniotic fluids, adipose tissues, and bone marrows. Depending on their sources, the therapeutical application of each MSC type has its own capacities, advantages, and drawbacks. The review discusses and compares the latest research studies on the use of different MSCs sources to treat renal failure. Concerns about the future clinical application of MSCs such as homing, toxicity, and the risk of immune rejection are also highlighted.

Human umbilical cord blood mononuclear cells protect against renal tubulointerstitial fibrosis in cisplatin-treated rats

Currently, there is no effective method to prevent renal interstitial fibrosis after acute kidney injury (AKI). In this study, we established and screened a new renal interstitial fibrosis rat model after cisplatin-induced AKI. Our results indicated that rats injected with 4 mg/kg cisplatin once a week for two weeks after firstly administrated with 6.5 mg/kg loading dose of cisplatin could set up a more accurate model reflecting AKI progression to renal interstitial fibrosis. Then, we investigated the effects and possible mechanisms of human umbilical cord blood mononuclear cells (hUCBMNCs) on renal tubular interstitial fibrosis after cisplatin-induced AKI. In rats injected with hUCBMNCs for four times, level of matrix metalloproteinase 7 (MMP-7) in serum and urine, urinary albumin/creatinine ratio, tubular pathological scores, the relative collagen area of the tubulointerstitial region, endoplasmic reticulum dilation and the mitochondrial ultrastructural damage were significantly improved. The level of reactive oxygen species, α-smooth muscle actin (α-SMA), [NOD]-like pyrin domain containing protein 3 and cleaved-Caspase 3 in renal tissue decreased significantly. However, in rats injected with hUCBMNCs for two times, no significant difference was discovered in MMP-7 levels and urinary albumin/creatinine ratio. Although expression of α-SMA and the percentage areas of collagen staining in tubulointerstitial tissues were ameliorated in rats injected with hUCBMNCs for two times, the effects were significantly weaker than those in rats injected with hUCBMNCs for four times. Taken together, our study constructed a highly efficient, duplicable novel rat model of renal fibrosis after cisplatin-induced AKI. Multiple injections of hUCBMNCs may prevent renal interstitial fibrosis after cisplatin-induced AKI.

Human umbilical cord blood mononuclear cells protect against renal tubulointerstitial fibrosis in cisplatin-treated rats

Currently, there is no effective method to prevent renal interstitial fibrosis after acute kidney injury (AKI). In this study, we established and screened a new renal interstitial fibrosis rat model after cisplatin-induced AKI. Our results indicated that rats injected with 4 mg/kg cisplatin once a week for two weeks after firstly administrated with 6.5 mg/kg loading dose of cisplatin could set up a more accurate model reflecting AKI progression to renal interstitial fibrosis. Then, we investigated the effects and possible mechanisms of human umbilical cord blood mononuclear cells (hUCBMNCs) on renal tubular interstitial fibrosis after cisplatin-induced AKI. In rats injected with hUCBMNCs for four times, level of matrix metalloproteinase 7(MMP-7)in serum and urine, urinary albumin/creatinine ratio, tubular pathological scores, the relative collagen area of the tubulointerstitial region, endoplasmic reticulum dilation and the mitochondrial ultrastructural damage were significantly improved. The level of reactive oxygen species, α-smooth muscle actin (α-SMA), [NOD]-like pyrin domain containing protein 3 and cleaved-Caspase 3 in renal tissue decreased significantly. However, in rats injected with hUCBMNCs for two times, no significant difference was discovered in MMP-7 levels and urinary albumin/creatinine ratio. Although expression of α-SMA and the percentage areas of collagen staining in tubulointerstitial tissues were ameliorated in rats injected with hUCBMNCs for two times, the effects were significantly weaker than those in rats injected with hUCBMNCs for four times. Taken together, our study constructed a highly efficient, duplicable novel rat model of renal fibrosis after cisplatin-induced AKI. Multiple injections of hUCBMNCs may prevent renal interstitial fibrosis after cisplatin-induced AKI.

Reparative and Regenerative Effects of Mesenchymal Stromal Cells-Promising Potential for Kidney Transplantation?

Mesenchymal stromal cells (MSCs) possess reparative, regenerative and immunomodulatory properties. The current literature suggests that MSCs could improve kidney transplant outcome via immunomodulation. In many clinical domains, research has also focussed on the regenerative and reparative effects of therapies with MSCs. However, in the field of transplantation, data on this subject remain scarce. This review provides an overview of what is known about the regenerative and reparative effects of MSCs in various fields ranging from wound care to fracture healing and also examines the potential of these promising MSC properties to improve the outcome of kidney transplantations.

Mesenchymal Stem Cells: a Promising Therapeutic Tool for Acute Kidney Injury

Acute kidney injury (AKI) is a rapid loss of renal function. It has high mortality rates. Still, renal replacement therapy is considered the best solution for recovering AKI. This opens a line of thought to develop an alternative therapy for it without complications. Mesenchymal stem cells are considered a new therapy for treating kidney diseases. The aim of this work was to address the anti-apoptotic, antioxidative, and pro-angiogenic effects of adipose tissue-derived MSCs (AD-MSCs) and bone marrow-MSCs (BM-MSCs) for treating AKI. Adult male Wistar rats were assigned into nine groups (n = 10): (1) the control group; (2) the AKI group, receiving cisplatin; (3) the AKI group treated with AD-MSCs (1 × 10⁶); (4) the AKI group treated with AD-MSCs (2 × 10⁶); (5) the AKI group treated with AD-MSCs (4 × 10⁶); (6) the AKI group treated with losartan; (7) the AKI group treated with BM-MSCs (1 × 10⁶); (8) the AKI group treated with BM-MSCs (2 × 10⁶); and (9) the AKI group treated with BM-MSCs (4 × 10⁶). The results showed a significant rise in creatinine, urea, and cystatin C (cys C) levels and upregulation of p38 mRNA, whereas a significant decline in NAD(P)H quinone oxidoreductase 1 (NQO-1) protein and downregulation of B-cell lymphoma-2 (Bcl-2) mRNA and vascular endothelial growth factor (VEGF) mRNA were recorded in AKI. MSCs could improve renal functions manifested by decreased urea, creatinine, and cys C levels; downregulation of p38; and upregulation of Bcl-2 and VEGF. Moreover, MSC therapy could induce NQO-1 in the treated rats relative to the untreated rats. So, cell-based therapy can reduce AKI through the antioxidative, anti-apoptotic, and pro-angiogenic properties of MSCs. Therefore, the findings received in this attempt create a fertile base for the setup of cell therapy in patients with AKI.

Hypoxic Preconditioned Mesenchymal Stromal Cell Therapy in a Rat Model of Renal Ischemia-reperfusion Injury: Development of Optimal Protocol to Potentiate Therapeutic Efficacy

Although previous and ongoing clinical studies have used stromal cells during renal ischemia-reperfusion injury (IRI), there is little consensus regarding the optimal protocol. We aimed to optimize the protocol for hypoxic preconditioned human bone marrow-derived mesenchymal stromal cell (HP-hBMSC) therapy in a rat model of renal IRI. We determined the optimal injection route (renal arterial, renal parenchymal, and tail venous injection), dose (low-dose: 1×10⁶, moderate-dose: 2×10⁶, and high-dose: 4×10⁶), and injection period (pre-, concurrent-, and post-IRI). During optimal injection route study, renal arterial injections significantly reduced the decreasing glomerular filtration rate (GFR), as compared to GFRs for the IRI control group, 2 and 4 days after IRI. Therapeutic effects and histological recoveries were the greatest in the group receiving renal arterial injections. During the dose finding study, high-dose injections significantly reduced the decreasing GFR, as compared to GFRs for the IRI control group, 3 days after IRI. Therapeutic effects and histological recoveries were the greatest in the high-dose injection group. While determining the optimal injection timing study, concurrent-IRI injection reduced elevated serum creatinine levels, as compared to those of the IRI control group, 1 day after IRI. Pre-IRI injection significantly reduced the decreasing GFR, as compared with GFRs for the IRI control group, 1 day after IRI. Therapeutic effects and histological recoveries were the greatest in the concurrent-IRI group. In conclusion, the concurrent-IRI administration of a high dose of HP-hBMSC via the renal artery leads to an optimal recovery of renal function after renal IRI.

Isolation and Characterization of Multipotent CD24+ Cells From the Renal Papilla of Swine

Over 100,000 patients in the United States are currently waiting for a kidney transplant. With just over 10,000 cadaveric kidneys transplanted annually, it is of the utmost importance to optimize kidney viability upon transplantation. One exciting avenue may be xenotransplantation, which has rejuvenated interest after advanced gene editing techniques have been successfully used in swine. Simultaneously, acute kidney injury (AKI) is associated with high morbidity and mortality and currently lacks effective treatment. Animal models have been used extensively to address both of these issues, with recent emphasis on renal progenitor cells (RPCs). Due to anatomical similarities to humans we aimed to examine progenitor cells from the renal papillae of swine kidneys. To do this, RPCs were dissected from the renal papillae of healthy swine. Cell surface marker expression, proliferation, and differentiation of the RPCs were tested in vitro. Additionally, a mixed lymphocyte reaction was performed to examine immunomodulatory properties. RPCs displayed spindle shaped morphology with limited self-renewing capacity. Isolated RPCs were positive for CD24 and CD133 at early passages, but lost expression with subsequent passaging. Similarly, RPCs displayed myogenic, osteogenic, and adipogenic differentiation capacities at passage 2, but largely lost this by passage 6. Lastly, direct contact of RPCs with human lymphocytes increased release of IL6 and IL8. Taken together, RPCs from the papilla of porcine kidneys display transient stem cell properties that are lost with passaging, and either represent multiple types of progenitor cells, or a multipotent progenitor population. In instances of ischemic insult, augmentation of/with RPCs may potentiate regenerative properties of the kidney. While the use of swine for transplantation and ischemia studies confers obvious advantages, the populations of different progenitor cell populations within pig kidneys warrants further investigation. Ultimately, while gene editing techniques enhance the potential for xenotransplantation of organs or cells, the ultimate success of this strategy may be determined by the (dis)similarities of RPCs from different species.

Stem/Stromal Cells for Treatment of Kidney Injuries With Focus on Preclinical Models

Within the last years, the use of stem cells (embryonic, induced pluripotent stem cells, or hematopoietic stem cells), Progenitor cells (e.g., endothelial progenitor cells), and most intensely mesenchymal stromal cells (MSC) has emerged as a promising cell-based therapy for several diseases including nephropathy. For patients with end-stage renal disease (ESRD), dialysis or finally organ transplantation are the only therapeutic modalities available. Since ESRD is associated with a high healthcare expenditure, MSC therapy represents an innovative approach. In a variety of preclinical and clinical studies, MSC have shown to exert renoprotective properties, mediated mainly by paracrine effects, immunomodulation, regulation of inflammation, secretion of several trophic factors, and possibly differentiation to renal precursors. However, studies are highly diverse; thus, knowledge is still limited regarding the exact mode of action, source of MSC in comparison to other stem cell types, administration route and dose, tracking of cells and documentation of therapeutic efficacy by new imaging techniques and tissue visualization. The aim of this review is to provide a summary of published studies of stem cell therapy in acute and chronic kidney injury, diabetic nephropathy, polycystic kidney disease, and kidney transplantation. Preclinical studies with allogeneic or xenogeneic cell therapy were first addressed, followed by a summary of clinical trials carried out with autologous or allogeneic hMSC. Studies were analyzed with respect to source of cell type, mechanism of action etc.

Extracellular vesicles from human-induced pluripotent stem cell-derived mesenchymal stromal cells (hiPSC-MSCs) protect against renal ischemia/reperfusion injury via delivering specificity protein (SP1) and transcriptional activating of sphingosine kinase 1 and inhibiting necroptosis

Renal ischemia-reperfusion is a main cause of acute kidney injury (AKI), which is associated with high mortality. Here we show that extracellular vesicles (EVs) secreted from hiPSC-MSCs play a critical role in protection against renal I/R injury. hiPSC-MSCs-EVs can fuse with renal cells and deliver SP1 into target cells, subsequently active SK1 expression and increase S1P formation. Chromatin immunoprecipitation (ChIP) analyses and luciferase assay were used to confirm SP1 binds directly to the SK1 promoter region and promote promoter activity. Moreover, SP1 inhibition (MIT) or SK1 inhibition (SKI-II) completely abolished the renal protective effect of hiPSC-MSCs-EVs in rat I/R injury mode. However, pre-treatment of necroptosis inhibitor Nec-1 showed no difference with the administration of hiPSC-MSCs-EVs only. We then generated an SP1 knockout hiPSC-MSC cell line by CRISPR/Cas9 system and found that SP1 knockout failed to show the protective effect of hiPSC-MSCs-EVs unless restoring the level of SP1 by Ad-SP1 in vitro and in vivo. In conclusion, this study describes an anti-necroptosis effect of hiPSC-MSCs-EVs against renal I/R injury via delivering SP1 into target renal cells and intracellular activating the expression of SK1 and the generation of S1P. These findings suggest a novel mechanism for renal protection against I/R injury, and indicate a potential therapeutic approach for a variety of renal diseases and renal transplantation.