A macrophage-activating factor (MAF) is a lymphokine or other receptor based signal that primes macrophages towards cytotoxicity to tumors, cytokine secretion, or clearance of pathogens.
[3] In addition, the phenotypes of the macrophages in a certain environment play a fundamental role in determining the immune activity and response within the tissue.
[2] After receiving signaling from both IFNγ and TNF, macrophages acquire a phenotype with higher activity against both pathogens and tumor cells.
[2] Initially, MAFs were thought to increase a macrophage’s cytotoxic response, allowing enhanced clearance of the tumor cells.
Chronic inflammation associated with activated macrophages may lead to the development of neoplasia, such as those found surrounding tuberculosis scars.
Regulatory macrophages produce Interleukin 10, which can inhibit cytotoxic responses of other lymphocytes to cancer cell antigens.