Furthermore, we found that the production of IgA but not IgG against 4 TAAs (CTAG1B, ANKRD30BL, COPS4, and SPAG8) as well as the IgA-TAA score was linked to the B cell maturation stages: the percentage of pre-germinal center (Bm2′ defined as CD19+IgD+CD38hi), germinal center (Bm3-4 defined as CD19+IgD−CD38hi) and early memory (eBm5 defined as CD19+IgD−CD38+) B cells was increased but the percentage of late memory B cells (Bm5 defined as CD19+IgD−CD38−) was similar or decreased in the IgA-positive as compared to IgA-negative BC samples (Figures 3C,D). The gene discussed is COPS4; the disease is breast cancer.