Inhibition of polymorphonuclear leukocyte chemotaxis by alpha-macrofetoprotein, an acute-phase reactant of the rat.
alpha-Macrofetoprotein (alpha M FP) is a normal fetal plasma constituent in the rat, with very low plasma levels in the adult phase but rising sharply after injury. This fetal acute-phase protein is a strong inhibitor of inflammatory edema. Fetal inflammatory reactions show diminished exudation, but also impaired emigration of polymorph nuclear cells (PMNs). Therefore we studied the effect of alpha M FP on chemotaxis of PMN in vitro and in vivo. In vitro experiments showed a strong inhibitory effect on casein-induced leukotaxis (Boyden technique) with a clear dose-effect relationship. In vivo with glycogen-induced pleurisy and peritonitis, high alpha M FP levels are accompanied by diminished PMN emigration and vice versa. The significance of these findings is discussed in relation to fetal pathology and also as a model showing the modulating effects of acute-phase proteins on the inflammatory reaction induced by tissue injury.
D000209:Acute-Phase Proteins; D000818:Animals; D000893:Anti-Inflammatory Agents; D002364:Caseins; D002634:Chemotaxis, Leukocyte / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D004804:Eosinophils; D005326:Fetal Proteins / Q000494:pharmacology; D007958:Leukocyte Count; D008214:Lymphocytes; D008297:Male; D009504:Neutrophils / Q000187:drug effects; D051381:Rats; D011919:Rats, Inbred Strains; D000511:alpha-Macroglobulins / Q000494:pharmacology
D000209:Acute-Phase Proteins; D000893:Anti-Inflammatory Agents; D002364:Caseins; D005326:Fetal Proteins; D000511:alpha-Macroglobulins