CD4 and type 1 diabetes mellitus: Fatty acid‐binding protein 4 (FABP4) is known to maintain the longevity and inflammatory function of TRM cells in human and rodent skin.[13] It is also a potential biomarker for pre‐eclampsia prediction in women with T1D[14] and we have shown that macrophage‐derived FABP4 enhances CD8+ T cell activation and shift of CD4+ helper T cells toward Th1 subtypes during the onset of T1D.[15] We hypothesized that FABP4 exacerbates adaptive immune activation through regulating TRM cell function.