title: Role of tyrosine kinases in IgE-mediated signal transduction in human lung mast cells and basophils.
abstract: Recent evidence suggests that tyrosine kinases play an important role in signal transduction mechanisms utilized by a range of different agonists in many cell types. We have investigated the effects of four different inhibitors of tyrosine kinases on IgE-dependent histamine release from human lung mast cells and basophils. Genistein inhibited the anti-IgE-induced histamine release from human basophils (at 10 microM genistein, inhibition = 55 +/- 5%, n = 17, P < 0.005) with an IC50 of 8 microM, but was much less effective in the human lung mast cell (at 10 microM, inhibition = 18 +/- 6%, n = 11, P < 0.05). Two inactive analogs of genistein, genistin and diadzein, failed to affect anti-IgE-induced histamine release significantly in either mast cells or basophils. A second inhibitor of tyrosine kinases, tyrphostin 25, inhibited IgE-dependent release from basophils (at 10 microM, inhibition = 25 +/- 7%, n = 6, P < 0.05) though it was less effective than genistein and failed to affect IgE-induced histamine release from human lung mast cells (at 10 microM, inhibition = 22 +/- 16%, n = 5, P = NS). In contrast, methyl 2,5 dihydroxycinnamate (MDC) failed to inhibit anti-IgE-dependent histamine release in human basophils (at 10 microM, inhibition = 3 +/- 3%, n = 5, P = NS) but proved to be an effective inhibitor of anti-IgE-induced degranulation in human lung mast cells (at 10 microM, inhibition = 53 +/- 16%, n = 5, P < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)
mesh_terms: D001491:Basophils / Q000502:physiology*; D002478:Cells, Cultured; D019833:Genistein; D006636:Histamine Release / Q000187:drug effects / Q000502:physiology; D006801:Humans; D007073:Immunoglobulin E / Q000502:physiology*; D007529:Isoflavones / Q000494:pharmacology; D008168:Lung / Q000166:cytology*; D008407:Mast Cells / Q000502:physiology*; D011505:Protein-Tyrosine Kinases / Q000037:antagonists & inhibitors / Q000502:physiology*; D015398:Signal Transduction / Q000502:physiology*
chemical_list: D007529:Isoflavones; D007073:Immunoglobulin E; D019833:Genistein; D011505:Protein-Tyrosine Kinases