Evidence that multinucleate giant cells are examples of mononuclear phagocytic differentiation.

Murine multinucleate giant cells and mononuclear phagocytes were examined with various quantitative cytochemical and autoradiographic techniques. No evidence was found that multinucleate giant cells were metabolically effete, in fact they compared favourably with mononuclear phagocytes. In addition, rat multinucleate giant cells consistently expressed surface Ia antigens and to a lesser degree fibronectin. It is suggested that multinucleate giant cells are a differentiated derivative of the mononuclear phagocytic system.