In PLA2R-associated membranous nephropathy, the risk allele of human leukocyte antigen-D locus is expressed on antigen-presenting cells and can present the epitope PLA2R to activate CD4 + helper T cells, and then drive the differentiation of activated B cells into plasma cells to produce anti PLA2R antibodies [27]. Here, CD4 is linked to membranous glomerulonephritis.