title: Characterization of inflammatory mediator release from purified human lung mast cells.
abstract: The release of inflammatory mediators (histamine, PGD2, TxB2, and LTC4) from purified human lung mast cells was characterized by kinetic and anti-IgE dose-response parameters. The relative rate of mediator release was histamine greater than PGD2 = TxB2 greater than LTC4, with one half maximal release occurring at approximately 2, 5, and 10 min, respectively. In 2 experiments, stimulation with anti-IgE caused significant quantities of platelet-activating factor (PAF) to appear rapidly (2 min) in the cell pellet; cell-associated PAF declined to low levels by 45 min. The optimal concentration of anti-IgE for the release of the arachidonate cyclooxygenase metabolites PGD2 and TxB2 (0.3 microgram/ml) was 10- to 30-fold less than that required for the release of histamine and LTC4 (3 to 10 micrograms/ml), suggesting that these release processes may have differential IgE Fc receptor cross-linking requirements. At optimal histamine release, the magnitude of the release of each arachidonate metabolite was found to correspond to the magnitude of histamine release, however, suggesting that the 2 processes are linked either in series or in parallel.
mesh_terms: D000888:Antibodies, Anti-Idiotypic / Q000276:immunology; D002469:Cell Separation / Q000379:methods; D006632:Histamine / Q000378:metabolism / Q000502:physiology; D006801:Humans; D007073:Immunoglobulin E / Q000276:immunology; D007700:Kinetics; D008168:Lung / Q000166:cytology / Q000378:metabolism*; D008407:Mast Cells / Q000276:immunology / Q000378:metabolism*; D010972:Platelet Activating Factor / Q000378:metabolism / Q000502:physiology; D011014:Pneumonia / Q000209:etiology*; D015230:Prostaglandin D2; D011457:Prostaglandins D / Q000378:metabolism / Q000502:physiology; D013189:SRS-A / Q000378:metabolism / Q000502:physiology; D013929:Thromboxane B2 / Q000378:metabolism / Q000502:physiology
chemical_list: D000888:Antibodies, Anti-Idiotypic; D010972:Platelet Activating Factor; D011457:Prostaglandins D; D013189:SRS-A; D007073:Immunoglobulin E; D013929:Thromboxane B2; D006632:Histamine; D015230:Prostaglandin D2