Macrophage Polarization and Infection

Monocytes and macrophages regulate host immune system against infectious pathogens. Activated macrophages play an important role in restricting the multiplication and dissemination of pathogens. The concept of alternative activation of macrophages might provide useful insights into pathology of infectious diseases. M1 macrophages (classically activated macrophages) and M2 macrophages (alternatively activated macrophages) are associated with responses to tissue remodeling, pro-inflammatory and anti-inflammatory reactions in various infectious diseases. However, the relevance of macrophage polarization in several infectious diseases was not revealed clearly. Macrophage plasticity and polarization should be considered as a useful conceptual framework for understanding the unknown pathogenesis of infectious diseases. Here we reviewed the recent progress on macrophage polarization and its characters in infectious diseases.