Progress in exploring the role of B-1 B cells and nAAbs in type 1 diabetes (T1D) has shown that B-1 B cell-derived N-acetylglucosamine-specific IgM binds β cell antigens, suppresses diabetogenic T cells, and delays T1D in recipients, suggesting a protective role in T1D [149]. Here, CD40LG is linked to type 1 diabetes mellitus.