IFNG and neoplasm: Macrophages polarize into M1 phenotype to perform their pathogen-scavenging function when exposed to T-helper 1 (Th 1) type cytokines or inflammatory mediators, such as interferon gamma (IFN-γ) and lipopolysaccharide (LPS) (7), or M2 phenotype to perform their anti-inflammatory effects, including wound healing and anti-tumor ability under conditions of exposure to Th 2 cytokines like IL-4 and IL-10 (8).