As shown in Fig. 3b-d, the frequencies of CXCR5 + CD4+ T cells, PD-1 + CXCR5 + CD4+ T cells and ICOS + CXCR5 + CD4+ T cells in CHC patients and HCV-related MC patients were significantly higher than in HCs, although the frequencies of these Tfh cell subsets were not statistically different in CHC patients and HCV-related MC patients. This evidence concerns the gene ICOS and cryohydrocytosis.