TGFB1 and neoplasm: Suppressive signals of MAC-MΦs were partly transmitted via humoral effectors, including reactive nitrogen intermediates (RNIs), TGF-β, and prostaglandin E, similar to other kinds of suppressor MΦs, such as those generated in tumor-bearing hosts (tumor-associated MΦs) and induced by mycobacterial (M. bovis BCG), protozoal, and helminth infections2, 5, 6, 7.