T-CELL REGULATION OF MACROPHAGE FUNCTION

Macrophage function has long been known to be controlled by activated T cells. As the cytokines that control macrophage activation are defin ed, it is becoming apparent that macrophage 'activation' is more subtl e than previously appreciated. Moreover, recent work has shown the dep endence of T-cell development on macrophages, from the costimulation o f T cells by macrophage surface molecules such as the B7 family, to th e modulation by monokines of T-cell phenotype and growth, including IL -7, IL-10, IL-12 and IL-15. Combinations of cytokines and costimulator s have revealed some of the processes by which an apparently dichotomo us T-cell response can regulate the subtle diversity of the immune res ponse.