title: Isolation of a lipid-soluble histamine release factor from human platelets.
abstract: We have isolated a histamine release factor from human platelet supernatants by heparin column chromatography, gel filtration and reversed phase HPLC. Fractions from each chromatographic step were assayed for histamine release factor activity (HRF). A peak of HRF activity was detected at a molecular mass of 60 kDa. Subsequent HPLC purification showed that the factor co-eluted with human serum albumin, but was totally extractable into the lipid phase. Comparison of biological activity with known basophil and eosinophil-activating hydroxyeicosanoids demonstrated similar activity with 5(S)-hydroperoxy-6E,8Z,11Z,14Z-eicosatetraenoic acid (5(S)-HPETE). The identification of this lipid soluble HRF demonstrates the novel potential role of an as yet unidentified lipid as an HRF, in the absence of priming stimuli.
authors.affiliation: Glaxo Institute for Molecular Biology, Geneva, Switzerland.
authors.forename: A E
authors.initials: AE
authors.lastname: Proudfoot
authors.forename: R
authors.initials: R
authors.lastname: Gatto
authors.forename: T N
authors.initials: TN
authors.lastname: Wells
authors.forename: K B
authors.initials: KB
authors.lastname: Bacon
mesh_terms: D000595:Amino Acid Sequence; D001792:Blood Platelets / Q000737:chemistry*; D006636:Histamine Release / Q000187:drug effects*; D006801:Humans; D015289:Leukotrienes / Q000494:pharmacology; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000737:chemistry; D012709:Serum Albumin / Q000737:chemistry
chemical_list: D015289:Leukotrienes; D010446:Peptide Fragments; D012709:Serum Albumin; C025348:arachidonic acid 5-hydroperoxide