摘要
AIM: TOtryptasepotentialinvestigate the ability of histamine to modulate release from human colon mast cells and the mechanisms.METHODS: Enzymatically dispersed cells from human colons were challenged with histamine, anti-IgE or calcium ionophore A23187 (CI), and the cell supernatants after challenge were collected. Tryptase release was determined with a sandwich ELISA procedure.RESULTS:Histamine at concentrations from 1ng/mL was able to induce a “bell” shape dose related release of tryptase from colon mast cells. The maximum release of tryptase was approximately 3.5 fold more than spontaneous release. As little as 10ng/ml histamine showed a similar potency to 10μg/mL anti-IgE in induction of tryptase release. Histamine induced release of tryptase initiated at 10s when histamine (100ng/mL) was added to cells, gradually increased thereafter, and completed at 5 rain.Both pertussis toxin or metabolic inhibitors were able to inhibit histamine induced tryptase release. When histamine and anti-IgE were added to colon mast cells at the same time, the quantity of tryptase released was similar to that induced by anti-IgE alone.The similar results were observed with CI. However, when various concentrations of histamine were incubated with cells for 20min before adding anti-IgE or CI, the quantity of tryptase released was similar to that was induced by histamine alone.CONCLUSION:Histamine is a potent activator of human colon mast cells, which represents a novel and pivotal selfamplification mechanism of mast cell degranulation.
AIM:To investigate the ability of histamine to modulate tryptase release from human colon mast cells and the potential mechanisms. METHODS:Enzymatically dispersed cells from human colons were challenged with histamine,anti-IgE or calcium ionophore A23187(CI),and the cell supernatants after challenge were collected.Tryptase release was determined with a sandwich ELISA procedure. RESULTS:Histamine at concentrations from 1ng/mL was able to induce a“bell”shape dose related release of tryptase from colon mast cells.The maximum release of tryptase was approximately 3.5 fold more than spontaneous release.As little as 10ng/mL histamine showed a similar potency to 10μg/mL anti-IgE in induction of tryptase release.Histamine induced release of tryptase initiated at 10s when histamine (100ng/mL)was added to cells,gradually increased thereafter,and completed at 5min.Both pertussis toxin or metabolic inhibitors were able to inhibit histamine induced tryptase release.When histamine and anti-IgE were added to colon mast cells at the same time,the quantity of tryptase released was similar to that induced by anti-IgE alone.The similar results were observed with CI.However,when various concentrations of histamine were incubated with cells for 20min before adding anti-IgE or CI,the quantity of tryptase released was similar to that was induced by histamine alone. CONCLUSION:Histamine is a potent activator of human colon mast cells,which represents a novel and pivotal self- amplification mechanism of mast cell degranulation.
基金
Supported by the National Natural science Foundation of China,No.30140023,and the Li Ka Shing Foundation,Hong Kong,China,No.C0200001
