CD4 and primary biliary cholangitis: A previous study demonstrated that through X-chromosome profiling data of PBC patients, there are distinct DNA methylation patterns in CD4, CD8, and CD14 cells; moreover, demethylation of the C-X-C chemokine receptor 3 (CXCR3) promoter leads to elevated expression of CXCR3 in CD4 T cells in early-stage PBC patients [36].