title: Release of interleukin I and low-molecular-weight lymphocyte-activating factors by rat peritoneal macrophages and its enhancement by acute non-specific inflammatory processes.
abstract: Peritoneal macrophages harvested from rats undergoing an acute non-specific inflammatory reaction induced by an injection of calcium pyrophosphate (CaPP) into the pleural cavity released increased amounts of interleukin I (IL-I)-like material. Lymphocyte-activating factors were also found in ultrafiltrates of the macrophage supernatants below 10 kd and 5 kd. A similar pattern of activity was observed when lysates of the macrophages were tested. In addition pre-exposure of normal peritoneal macrophages to an acute pleural inflammatory exudate before supernatant production enhanced the release of lymphocyte-activating factors found both in the unfractionated supernatant and a sub-5-kd ultrafiltrate. Thus these results demonstrate that an acute inflammatory reaction, initiated by a non-antigenic stimulus is able to stimulate macrophages remote from the inflammatory site to produce a factor which behaves like IL-I in a standard IL-I assay. The presence of low-molecular-weight factors (less than 5 kd) with similar activity may suggest that degradation of IL-I has taken place to yield active fragments. Acute inflammatory exudate also augments release of these factors which may be important in the pathogenesis of inflammation.
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D005260:Female; D007249:Inflammation / Q000378:metabolism*; D007375:Interleukin-1 / Q000096:biosynthesis*; D008070:Lipopolysaccharides; D008213:Lymphocyte Activation / Q000187:drug effects*; D008264:Macrophages / Q000378:metabolism*; D008297:Male; D051379:Mice; D008809:Mice, Inbred C3H; D008938:Mitosis; D051381:Rats; D011919:Rats, Inbred Strains; D013601:T-Lymphocytes / Q000276:immunology
chemical_list: D007375:Interleukin-1; D008070:Lipopolysaccharides