This system was accompanied by the presence of CpG DNA, a classical inducer of B cell activation, which has been widely used in studies of lupus autoantibody secretion.[24] Pronouncedly, higher proportions of proliferating B cells, plasma cells and IgG/IgM antibodies‐producing B cells were observed in the co‐culture model (Figure 5K; Figure S11, Supporting Information), indicating that ILC3s promote the activation process and effector functions of B cells. The gene discussed is CD40LG; the disease is systemic lupus erythematosus.