macrophage activating factor

macrophage activating factor (MAF)

Etymology: Gk. makros, large, phagein, to eat; L, activus, active, facere, to make

a lymphokine released from a sensitized leukocyte that induces changes in the appearance and function of macrophages and makes them active against certain antigens.

macrophage activating factor

Any of a heterogeneous group of lymphokines secreted by sensitised lymphocytes, the most potent of which is IFN-gamma. IFN-activated macrophages have increased bactericidal and tumouricidal activity and morphological evidence of “maturation”—e.g., increased spreading, pseudopod formation and vacuolisation.

macrophage activating factor

Abbreviation: MAF

A lymphokine that stimulates macrophages to become more effective killers of certain microbial cells. Macrophages stimulated by MAF can kill tumor cells.

See also: factor