IL10 and myeloid sarcoma: IL-10- producing B cells play an important role in controlling autoimmunity, such as in EAE, an animal model of MS, and in a systemic lupus erythematosus (SLE)-like disease that develops in the Lyn-deficient mouse and during murine cytomegalovirus (MCMV4) infection (Fillatreau et al., 2002; Madan et al., 2009; Scapini et al., 2011).