The higher expression of HLA-DQA1 in T1DM than in normal samples affected the encoding level of DQ2.5 and DQ8 molecules on the APC surface, which can promote the presentation of self-antigens to induce autoimmunity, and present gluten antigens to homologous CD4+ T cells, thereby promoting T cell activation and proliferation [25]. Here, CD4 is linked to type 1 diabetes mellitus.