MRC1 and neoplasm: To investigate this, we used flow cytometric analysis to analyze macrophage expression of major histocompatibility complex class II (MHCII) and mannose receptor (CD206) on pulmonary macrophages isolated from tumor-bearing mice, mice that underwent surgical resection of their tumor-bearing limb, or mice that underwent amputation of their contralateral limb, leaving their primary tumor in place.