CD40LG and B-cell chronic lymphocytic leukemia: Recent findings have revealed that secretory IgM enhances the immunosuppressive activities of MDSCs in chronic lymphocytic leukemia (CLL) and LLC syngeneic mouse lung cancer models; in addition, the negative impact of secretory IgM was counteracted by the genetic loss of XBP1s, leading to effective T cell-mediated control of the tumor [191].