Regulation of macrophage accessory functions by interactions involving lymphokines and endotoxin.

It is important to reemphasize the observation that two distinct regulatory molecules, colony-stimulating factor (CSF) and interferon, can directly influence macrophage accessory functions. CSF stimulates macrophages to secrete interleukin 1 (IL 1) whereas interferon induces a conversion to Ia antigen expression. Either directly or indirectly these functions can also be influenced by a combination of lymphokines and bacterial lipopolysaccharides (LPS). As is the case with effector functions, it is apparent that specific regulatory molecules exist which function to amplify the influence of microbial products on macrophage accessory activities.