MRC1 and neoplasm: In tumor bearing mice models, TAMs also induce chemotherapy resistance through various mechanisms, such as secretion of “chemoprotective” factors including lysosomal enzyme, cathepsins B and S. [12, 13] TAMs tends to be alternative activated, or M2, macrophages, characterized by high production of anti-inflammatory cytokine, IL-10, and up-regulation of cell-surface scavenger receptors, such as mannose receptor (CD206) and hemoglobin scavenger receptor (CD163).