Enhancing islet transplantation outcomes in T1DM: The promise of mesenchymal stem cells and exosomes.

Islet transplantation represents a promising therapeutic strategy for type 1 diabetes mellitus (T1DM), yet its clinical application is constrained by hypoxia, oxidative stress, and immune rejection during islet isolation, culture, and post-transplantation. In recent years, mesenchymal stem cells (MSCs) have demonstrated the ability to enhance islet survival and function through immunomodulation, anti-inflammatory effects, and paracrine signaling. Among the secreted components, exosomes have emerged as key mediators of MSC function, capable of delivering nucleic acids, proteins, and lipids to target cells with high biocompatibility and low immunogenicity. This review highlights recent advances in utilizing MSCs and MSC-derived exosomes to improve islet engraftment and long-term function. Particular emphasis is placed on exosome engineering strategies-such as therapeutic cargo loading and targeted delivery-as well as encapsulation techniques that facilitate sustained release and graft protection. Despite encouraging preclinical results, the field remains in its early stages, and further research is required to standardize exosome isolation, elucidate mechanisms of action, and ensure clinical translatability. Harnessing the full potential of MSC-derived exosomes may offer a next-generation approach for achieving durable glycemic control and β-cell regeneration in T1DM.