CD40LG and plasma cell myeloma: In human multiple myeloma cell cultures (ARH-77 cell line), IGU inhibits spontaneous IgG antibody production without affecting cell proliferation, and in human peripheral blood B cells induced by autologous T cells and anti-CD3 antibodies, IGU suppresses the production of both IgM and IgG, effectively inhibiting immunoglobulin production in B cells without causing blockage (Zeng et al., 2022a).