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Characterization of mononuclear cell-derived histamine release enhancing factor
R E Younger1, H G Herrod, P L Lieberman
1Department of Pediatrics, University of Tennessee Center for the Health Sciences, Chattanooga 37403.
Abstract:
Histamine release enhancing factor (HREF) is a product of phytohemagglutinin-stimulated mononuclear cells that substantially augments in vitro IgE-mediated basophil histamine release. The factor is stable at 56 degrees C and has a molecular weight in the 10,000 to 30,000 dalton range. The magnitude of HREF activity produced is dependent on the concentration of mononuclear cells cultured and the final concentration of HREF during basophil challenge. The HREF phenomenon could not be attributed to phytohemagglutinin, alpha- or gamma-interferon, arachidonic acid metabolites, or interleukin-1 or 2. HREF appears to be a unique cytokine of potential importance in the immunology of inflammatory and atopic processes.
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