Treatment of diabetic mice by microfluidic system-assisted transplantation of stem cells-derived insulin-producing cells transduced with miRNA

Immune Evasion in Stem Cell-Based Diabetes Therapy-Current Strategies and Their Application in Clinical Trials

Background/Objectives: Human pancreatic islet transplantation shows promise for long-term glycemic control in diabetes patients. A shortage of healthy donors and the need for continuous immunosuppressive therapy complicates this. Enhancing our understanding of the immune tolerance mechanisms related to graft rejection is crucial to generate safer transplantation strategies. This review will examine advancements in immune protection strategies for stem cell-derived islet therapy and discuss key clinical trials involving stem cell-derived β-cells and their protective strategies against the host immune system. Methods: A comprehensive literature search was performed on peer-reviewed publications on Google Scholar, Pubmed, and Scopus up to September 2024 to extract relevant studies on the various strategies of immune evasion of stem cell-derived β-cells in humans. The literature search was extended to assimilate all relevant clinical studies wherein stem cell-derived β-cells are transplanted to treat diabetes. Results: Our analysis highlighted the importance of human pluripotent stem cells (hPSCs) as a potentially unlimited source of insulin-producing β-cells. These cells can be transplanted as an effective source of insulin in diabetes patients if they can be protected against the host immune system. Various strategies of immune protection, such as encapsulation and genetic manipulation, are currently being studied and clinically tested. Conclusions: Investigating immune tolerance in hPSC-derived islets may help achieve a cure for diabetes without relying on exogenous insulin. Although reports of clinical trials show promise in reducing insulin dependency in patients, their safety and efficacy needs to be further studied to promote their use as a long-term solution to cure diabetes.

Insights into the development of insulin-producing cells: Precursors correlated involvement of microRNA panels

Type 1 diabetes (T1D) is a chronic autoimmune condition characterized by the destruction of pancreatic β cells, recently estimated to affect approximately 8.75 million individuals worldwide. At variance with conventional management of T1D, which relies on exogenous insulin replacement and insulinotropic drugs, emerging therapeutic strategies include transplantation of insulin-producing cells (IPCs) derived from stem cells or fully reprogrammed differentiated cells. Through the in-depth analysis of the microRNAs (miRNAs) involved in the differentiation of human embryonic stem cells (ESCs), mesenchymal stem cells (MSCs), and induced pluripotent stem cells (iPSCs), into insulin-producing cells, this review provides a comprehensive overview of the molecular mechanisms orchestrating the transformation of precursors to cells producing insulin. In addition to miR-375, involved in all differentiation processes, and to miR-7, mir-145 and miR-9, common to the generation of insulin-producing cells from at least two different sources, the literature reveals panels of miRNAs closely related to precursor cells and associated with specific events of the physiological β cell maturation. Since the forced modulation of miRNAs can direct cells development towards insulin-producing cells or modify their fate, a more comprehensive knowledge of the miRNAs involved in the cellular events leading to obtain efficient β cells could improve the diagnostic, prognostic, and therapeutic approaches to diabetes.

The role of noncoding RNAs in beta cell biology and tissue engineering

The loss or dysfunction of pancreatic β-cells, which are responsible for insulin secretion, constitutes the foundation of all forms of diabetes, a widely prevalent disease worldwide. The replacement of damaged β-cells with regenerated or transplanted cells derived from stem cells is a promising therapeutic strategy. However, inducing the differentiation of stem cells into fully functional glucose-responsive β-cells in vitro has proven to be challenging. Noncoding RNAs (ncRNAs) have emerged as critical regulatory factors governing the differentiation, identity, and function of β-cells. Furthermore, engineered hydrogel systems, biomaterials, and organ-like structures possess engineering characteristics that can provide a three-dimensional (3D) microenvironment that supports stem cell differentiation. This review summarizes the roles and contributions of ncRNAs in maintaining the differentiation, identity, and function of β-cells. And it focuses on regulating the levels of ncRNAs in stem cells to activate β-cell genetic programs for generating alternative β-cells and discusses how to manipulate ncRNA expression by combining hydrogel systems and other tissue engineering materials. Elucidating the patterns of ncRNA-mediated regulation in β-cell biology and utilizing this knowledge to control stem cell differentiation may offer promising therapeutic strategies for generating functional insulin-producing cells in diabetes cell replacement therapy and tissue engineering.

Encapsulation of stem-cell derived β-cells: A promising approach for the treatment for type 1 diabetes mellitus

Type 1 diabetes mellitus is an auto-immune disease causing the T-cell mediated destruction of insulin-producing β-cells, resulting in chronic hyperglycemia. Current treatments such as insulin replacement therapy or the transplantation of pancreas or pancreatic islets present major disadvantages such as the constant need of drugs, as well as a shortage of donor organs. In this review, we discuss a sustainable solution to overcome these limitations combining the use of β-cells, derived from stem cells, and their encapsulation within a protective matrix. This article provides an exhaustive overview of currently investigated stem cell sources including embryonic, mesenchymal as well as induced pluripotent stem cells in combination with various up to date encapsulation methods allowing the formation of immuno-protective devices. In order to identify current limitations of this interdisciplinary therapeutic approach and to find sustainable solutions, it is essential to consider key aspects from all involved domains. This includes biological parameters such as the stem cell origin but also the different aspects of the encapsulation process, the used materials and their physico-chemical properties such as elasticity, porosity and permeability cut-off as well as the best implantation sites allowing efficient and self-autonomous control of glycemia by the transplanted encapsulated cells.

Natural Biopolymers as Additional Tools for Cell Microencapsulation Applied to Cellular Therapy

One of the limitations in organ, tissue or cellular transplantations is graft rejection. To minimize or prevent this, recipients must make use of immunosuppressive drugs (IS) throughout their entire lives. However, its continuous use generally causes several side effects. Although some IS dose reductions and withdrawal strategies have been employed, many patients do not adapt to these protocols and must return to conventional IS use. Therefore, many studies have been carried out to offer treatments that may avoid IS administration in the long term. A promising strategy is cellular microencapsulation. The possibility of microencapsulating cells originates from the opportunity to use biomaterials that mimic the extracellular matrix. This matrix acts as a support for cell adhesion and the syntheses of new extracellular matrix self-components followed by cell growth and survival. Furthermore, by involving the cells in a polymeric matrix, the matrix acts as an immunoprotective barrier, protecting cells against the recipient’s immune system while still allowing essential cell survival molecules to diffuse bilaterally through the polymer matrix pores. In addition, this matrix can be associated with IS, thus diminishing systemic side effects. In this context, this review will address the natural biomaterials currently in use and their importance in cell therapy.

hMSCs Migrate under the Chemotaxis of CXCL-13 and Enhance Islet B Cell Activity through p-AKT Signaling Pathway in High-Glucose Environment

As a common clinical chronic disease, the incidence of diabetes is increasing year by year. According to the latest statistics from the International Diabetes Federation, as of 2019, the global prevalence of diabetes has reached 8.3%. This study aims to investigate the effect of CXCL-13 on the migration ability of human mesenchymal stem cells (hMSCs) and to clarify the specific molecular mechanism of the protective effect of hMSCs on islet B cells. The hMSCs were cultured in high-glucose environment, and the effect of CXCL-13 on the migration ability of hMSCs was determined by Transwell experiment. After coculture of hMSCs and islet B cells, the activity of cells was detected by CCK8 assay, the expression of Ki-67 in cells was detected by RT-PCR, and the expression of P53 was detected by Western blot to investigate the effect of hMSCs on the proliferation and apoptosis of islet B cells. The effect of hMSCs on the function of islet B cells was determined by glucose stimulated insulin secretion experiment. Transwell experiment results showed that CXCL-13 could promote the migration of hMSCs to islet B cells in high-glucose environment. The results of CCK-8 showed that the cell activity in the coculture group was significantly higher than that of the other groups, and RT-PCR showed that the expression of Ki-67 was significantly increased in the coculture group of hMSCs and islet B cells. The results of Western blot showed that the expression of P53 was significantly decreased in the coculture group, and the glucose stimulated insulin secretion test showed that insulin secretion was significantly increased. It was found that after the inhibition of ATK, cell activity was significantly reduced, and apoptosis was significantly increased. Meanwhile, the expression of Ki-67 was inhibited, the expression of P-53 was significantly increased, and insulin secretion was significantly reduced. To sum up, in a high-glucose environment, CXCL-13 effectively promoted the migration of hMSCs, and hMSCs protected the activity and function of islet B cells through Akt signaling pathway.