Advances in Vascularization of Islet Organoids: Engineering Strategies, Functional Evaluation, and Transplantation Applications

Abstract

The growth and evolution of diabetes, especially Type 1 and Type 2, are highly correlated to the failure of islet β cells and consequently replacing of β cells is an area of interest in research. In recent years, stem cell-based islet organoids have offered a novel therapeutic approach to diabetes treatment; nevertheless, additional functional development and clinical use remain restricted due to the absence of vascular microenvironment. The present paper discusses main engineering strategies, evaluation parameters, revascularization after transplantation and clinical translation issues concerning vascularization of islet organoids. Recent vascularization methods have largely involved co-culturing with vascular-associated cells, building vascular organoids and multi-lineage co-differentiation. Such strategies have been shown to have some success at promoting beta-cell maturation, increasing glucose sensitivity, and boosting post-transplantation survival rates. However, at this stage of development, research has faced the challenge of insufficient vascular maturity, poor long-term perfusion performance, low efficiency of integration in vivo, and the challenge of achieving both immune protection and fast vascularization. Further studies should be conducted to create working vascular systems and reach synergistic optimization in immune regulation, anti-fibrosis design and standardized preparation to promote the clinical use of islet organoids in cellular replacement therapy in diabetes.