Abstract Background Type 1 diabetes (T1D) is a lifelong autoimmune disease characterised by progressive immune‐mediated destruction of insulin‐producing beta (β)T1D‐cells, leading to permanent insulin dependence and increased risk of microvascular and macrovascular complications. Despite advances in autoantibody screening and immunotherapies, major clinical challenges persist in early detection, accurate disease staging, prediction of progression and monitoring of therapeutic response. Current biomarkers provide limited insight into real‐time β‐cell stress and immune activity, restricting opportunities for timely and personalised intervention. Rationale Extracellular vesicles (EVs) are nano‐sized membrane‐bound particles released by virtually all cell types and carry proteins, lipids and nucleic acids reflective of their cellular origin and physiological state. Advances in EV isolation, multi‐omics profiling and bioinformatics now enable detailed characterisation of EV cargo from accessible biofluids such as blood and urine. These developments position EVs as a minimally invasive platform to interrogate β‐cell health, immune activation and systemic complications in T1D, while also offering a novel class of cell‐free immunomodulatory therapeutics. Content This review synthesises current evidence on the role of EVs in T1D pathogenesis and clinical translation. We discuss how β‐cell‐ and immune cell‐derived EVs participate in antigen presentation, immune activation and inflammatory amplification, and how EV cargo signatures (proteins, miRNAs and other RNAs) reflect disease stage, progression and heterogeneity. We summarise emerging data on maternal, neonatal and urinary EVs as early‐life and complication‐associated biomarkers, and critically evaluate ongoing EV‐based clinical studies in T1D. Finally, we examine the therapeutic potential of stem cell‐derived and engineered EVs to modulate autoimmunity and preserve residual β‐cell function. Conclusion EVs introduce a potentially clinically actionable layer of information linking cellular stress, immune dysregulation and tissue damage to measurable biomarkers and therapeutic opportunities in T1D. However, the majority of EV applications currently remain at the preclinical or early pilot‑study stage, with limited validation in large, longitudinal patient cohorts. Key challenges include biological heterogeneity, assay reproducibility and the need for standardised isolation, characterisation and regulatory frameworks. While rapid advances in EV technologies and early proof‑of‑concept clinical studies support their long‑term potential, substantial work is required before routine clinical implementation is feasible. For feasible clinical translation of EV‐based applications, alignment with regulatory frameworks must be considered early to ensure analytical validity, standardisation and compliance with clinical and diagnostic approval pathways, as well as to address safety, efficacy and manufacturing requirements for EV‐based therapeutics. Key points EVs provide a minimally invasive window into β‐cell stress, immune activation and disease progression in T1D. EV‐associated proteins and RNAs reflect disease stage, heterogeneity and response to immunotherapy beyond traditional biomarkers. Circulating and urinary EVs show promise for early detection of T1D complications before clinical manifestation. Stem cell‐derived and engineered EVs represent emerging cell‐free immunomodulatory and regenerative therapies. Standardisation, longitudinal validation, EV‐focused clinical trial design and early alignment with regulatory frameworks are essential for clinical translation, ensuring robust validation for diagnostics and addressing safety, efficacy and manufacturing requirements for EV‐based therapeutics.
Jayabalan et al. (2026) studied this question.