found lower HBsAg in patients treated with PEG-IFN-α who had increased PD-1 hi CXCR5 + CD4 + T cells, suggesting that the increase in Tfh with high PD-1 expression promotes a decrease in HBsAg (160) It has also been suggested that PD-1 hi CD4 + CXCR5 + Tfh cells, may be involved in the pathogenesis of HBV-associated membranous nephropathy by promoting the secretion of corresponding antibodies leading to the deposition of antigen-antibody complexes (161). The gene discussed is CD4; the disease is membranous glomerulonephritis.