WORLD JOURNAL OF ADVANCE
HEALTHCARE RESEARCH

Moges Maru and Gashaw Getaneh*

ABSTRACT

The macrophage is the major differentiated cell of a phylogenetically primitive system of cells termed the mononuclear phagocyte system. Macrophages are widely distributed throughout the body, displaying great structural and functional heterogeneity. Macrophages act as a second line of defense against such foreign invaders, either as stationary or as mobile cells and are also able to signal other types of white blood cell, particularly lymphocytes, and other immune cells to the site of infection to help fight it off. They are specialized phagocytic cells that chase down and destroy cancer cells. In most tumors, tumor-associated macrophages (TAMs) show properties of an alternative polarization phenotype characterized by the expression of a series of chemokines, cytokines, and proteases that promote immunosuppression, tumor proliferation, and spreading of the cancer cells. Macrophages function in both non-specific defense (innate immunity) as well as help initiate specific defense mechanisms (adaptive immunity) of vertebrate animals. Most importantly macrophages process and present antigens on the surface of the membrane.