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bioRxiv · 10.1101/2025.10.24.684420

Proinflammatory circulating extracellular vesicles from type 1 diabetes patients contribute to beta cell cytotoxicity and disease pathogenicity

Abstract

In Type 1 diabetes (T1D), {beta}-cell loss and autoimmunity initiate years before disease diagnosis. However, the mechanisms remain unknown. Here, we investigated the role and mechanisms of circulating extracellular vesicles (cEVs) on T1D pathogenesis and {beta}-cell cytotoxicity. We used cEVs isolated from healthy donors (HD), T1D, multiple autoantibody-positive (AAb+), pre- and post-islet transplantation T1D subjects, NOD-T1D mice, and T1D PBMCs. Patient T1D-cEVs significantly induced apoptosis in vitro in human {beta}-cells but not -cells compared to HD-cEVs. cEVs from AAb+ subjects and pre-diabetic mice were cytotoxic, demonstrating that cEV-induced {beta}-cell cytotoxicity precedes T1D onset and diagnosis. cEV reduction in prediabetic NOD-T1D mice improved {beta}-cell health implying cEV contribution to T1D development. Proteomic analysis of patient T1D-cEVs found several proinflammatory proteins, including interferon gamma, which induced {beta}-cell cytotoxicity. Our data using cEVs from pre- and post-islet transplant and PBMC-EVs from T1D patients implicated immune cells as a potential cellular source of cytotoxic cEVs in T1D. Collectively, our data using T1D patient samples coupled with studies in mice demonstrate that cEVs contribute to {beta}-cell cytotoxicity and to the progression of T1D pathogenicity. Our study is one of the first to demonstrate a functional role of the proinflammatory cEV protein cargo on glucose homeostasis, {beta}-cell health, and insulitis. Our studies on T1D-cEVs may lead to discovery of novel biomarkers and therapeutic targets for T1D.

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BibTeXRIS

Guthalu Kondegowda, N., Cisneros, Z., Roeth, D., Do, J.-s., Filipowska, J., Li, R., Zhang, S., Ogyaadu, S., Jayasena, C. S., Jovanovic-Talisman, T., Wasserfall, C., Yuan, Y.-C., Reijonen, H., Kalkum, M., Levy, C. J., Kandeel, F., Sahoo, S., Vasavada, R. C.. 2025-10-26. Proinflammatory circulating extracellular vesicles from type 1 diabetes patients contribute to beta cell cytotoxicity and disease pathogenicity. https://doi.org/10.1101/2025.10.24.684420

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