Recent studies suggest that lower alpha-diversity and the characteristic of a pro-inflammatory environment in gut microbiota dysbiosis promote insulitis by activating and proliferating pancreatic‐draining lymph node T cells, particularly diabetogenic CD8+ T cells, which may contribute to the risk of developing type 1 diabetes (T1D) in genetically predisposed individuals (9). This evidence concerns the gene CD8A and type 1 diabetes mellitus.