Protein kinase C modulates immunoglobulin E-mediated activation of human mast cells from lung and skin. I. Pharmacologic inhibition.
It is widely appreciated that protein kinase C (PKC) is activated in a variety of secretory cells after stimulation. By using two complementary pharmacologic approaches, we have investigated the role of PKC in immunoglobulin E (IgE)-mediated secretion from human lung, bronchoalveolar lavage and skin mast cells. We examined the effect of the PKC inhibitor, staurosporine, on goat anti-human IgE-induced mediator release. In lung mast cells, the IC50 for staurosporine on histamine release was 2.8 +/- 1.4 nM (n = 9). The drug was slightly more potent in skin mast cells where the IC50 was 0.64 +/- 2.0 nM (n = 6), but staurosporine had no effect on the IgE-mediated release of histamine from bronchoalveolar lavage mast cells. Mast cells were also incubated overnight with the phorbol ester 12-O-tetradecanoylphorbol-13-acetate (TPA) to down regulate PKC and the response to goat anti-human IgE was measured. Prolonged exposure to 100 ng/ml of TPA reduced IgE-mediated histamine release from 28 +/- 6 to 6 +/- 1% in the skin mast cells whereas similar treatment only reduced the response of lung mast cells from 36 +/- 5 to 26 +/- 6%. Despite using agents which act by different mechanisms, short-term inhibition with staurosporine and long-term treatment with TPA, we obtained consistent results which suggest that PKC is playing a prorelease role in IgE-mediated signaling. Our results also suggest that skin and lung mast cells are more sensitive to PKC down-regulation than bronchoalveolar mast cells. This heterogeneity between human mast cells at the level of PKC regulation of cell activation is previously undescribed.
Massey
W A
WA
Division of Clinical Immunology, Johns Hopkins Asthma and Allergy Center, Baltimore, Maryland.
Cohan
V L
VL
MacGlashan
D W
DW
Gittlen
S W
SW
Kagey-Sobotka
A
A
Lichtenstein
L M
LM
Warner
J A
JA
D000470:Alkaloids / Q000494:pharmacology; D000888:Antibodies, Anti-Idiotypic / Q000494:pharmacology; D016718:Arachidonic Acid; D001095:Arachidonic Acids / Q000378:metabolism; D001992:Bronchoalveolar Lavage Fluid / Q000166:cytology / Q000201:enzymology; D000001:Calcimycin / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D006636:Histamine Release / Q000187:drug effects; D006801:Humans; D007073:Immunoglobulin E / Q000276:immunology / Q000494:pharmacology / Q000502:physiology*; D008168:Lung / Q000166:cytology / Q000187:drug effects / Q000201:enzymology*; D008407:Mast Cells / Q000187:drug effects / Q000201:enzymology*; D011493:Protein Kinase C / Q000037:antagonists & inhibitors* / Q000378:metabolism / Q000502:physiology; D015398:Signal Transduction / Q000187:drug effects / Q000502:physiology; D012867:Skin / Q000166:cytology / Q000187:drug effects / Q000201:enzymology*; D019311:Staurosporine; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D013997:Time Factors
D000470:Alkaloids; D000888:Antibodies, Anti-Idiotypic; D001095:Arachidonic Acids; C026408:anti-IgE antibodies; D016718:Arachidonic Acid; D007073:Immunoglobulin E; D000001:Calcimycin; D011493:Protein Kinase C; D019311:Staurosporine; D013755:Tetradecanoylphorbol Acetate