Macrophage-mediated cytotoxicity: its possible role in rheumatoid arthritis.

The association of macrophages with destructive processes in transplantation and tumoral, bacterial, and protozoan immunity illustrates their versatility in different situations. Their participation in inflammatory responses, including graft rejection and rheumatoid arthritis, would guarantee focal areas of high concentrations of hydrolytic enzymes and other macrophage products. That erosion of synovial tissue occurs in the presence of enzymes known to be associated with macrophages suggests that the large numbers of infiltrating macrophages and destruction of synovial tissue may be related.