MAC is the acronym for "membrane attack complex". MAC is an immunological defense system coordinated and integrated by the individual components of the complement system with the goal of eliminating an endogenous or exogenously invaded pathogenic cell by cytolysis. The generation of the membrane attack complex is an essential part of innate (non-specific) immunity. For further information see below. Membrane Attack Complex.
MAC is also a medical abbreviation for Mycobacterium avium or Mycobacterium avium complex.