PLATELET ACTIVATING FACTOR - AN INHIBITOR OF NEUTROPHIL ACTIVATION

Google Scholar
  • 1 January 1981
    • journal article
    • research article
    • Vol. 43  (1) , 135-142
Abstract
Preparations of platelet-activating factor (PAF) derived by methanolic extraction of supernatants from antigen-challenged rabbit basophils proved capable of activating platelets while concurrently inhibiting [human or rabbit] neutrophil aggregation and/or secretion stimulated by biologically active F-Met peptides, ionophore A23187 or zymosan-treated serum. This inhibition was non-cytotoxic and species non-specific. When these PAF preparations were analyzed using TLC, multiple lipids were detected. Platelet-stimulating and neutrophil-inhibitory activity was present in a lipid component migrating at an Rf consistent with native PAF; however, these biological activities were not limited only to PAF and could also be detected in lipid with solubility characteristics more closely related to a lysophosphatide than to native PAF. Native PAF may belong to a family of biologically active lipids differing somewhat in physicochemical properties. PAF and/or PAF-like molecules may also demonstrate a biological activity distinct from their effects on the platelet.