THE BIOLOGY OF SAA: IDENTIFICATION OF THE INDUCER, IN VITRO SYNTHESIS, AND HETEROGENEITY DEMONSTRATED WITH MONOCLONAL ANTIBODIES

摘要: Continued studies of the macrophage-derived mediator SAA synthesis (SAA Stimulating Factor) confirm our previous observations that SAASF copurified with leukocytic pyrogen (LP) and lymphocyte activating factor (LAF). Moreover, new data demonstrate three separate isoelectric points for human LP-LAF-SAASF each which possess biological activities. During purification 15,000 MW LP from crude stimulated mononuclear cell supernatants, only those fractions pyrogenic activity in rabbits caused augmented stimulation lymphocytes (LAF) induced mice. Purified isolated mouse hepatocytes vitro to synthesize a dose-responsive manner. Colchicine treatment led decreased secretion into medium an intracellular accumulation SAA. Messenger RNA was livers endotoxin-stimulated mice translated wheat-germ cell-free system. A major product identified at 13-14,000 MW. Immunoprecipitation anti-mouse AA several bands on autoradiography polyacrylamide gels. These larger precursors may account previously noted heterogeneity SAA, comprising least 6 isomers, similar molecular weight but different solubility electrophoretic charge characteristics. Two monoclonal antibodies (IgM-K IgG1-K) have been prepared using standard hybridization techniques. They are directed variable COOH terminal region since they detect differences between SAAs do not react human, monkey, dog or proteins, AP, C-reactive protein, IgG nor albumin. will be useful examining origin, structure function