CXCR3 and type 1 diabetes mellitus: Recently, the studies of the role of CXCR3+ and CCR4+ T cells in the pathogenesis of T1D have suggested the importance of pancreatic β cells infiltration with CXCR3+ T cells in T1D patients [15–19], while the role of CCR4+ T cells in T1D still remains controversial [20].