reported that expression of TIGIT, PD-1, and TIM-3 was significantly increased on CD4+ T cells from RA synovial fluid mononuclear cells (SFMCs) compared to CD4+ T cells from both RA PBMCs and HC PBMCs and they found a positive correlation with TIGIT expression and disease activity (61). The gene discussed is HAVCR2; the disease is rheumatoid arthritis.