Effect of proteinase activated receptorª²2 agonists on histamine and tryptase release from human skin and tonsil mast cells

    XIE Hua, HE Shaoª²Heng, FU Yiª²Ling

    Allergy and Inflammation Research Institute, Medical College, Shantou University, Shantou 515031, China

    ¡¾Abstract¡¿ AIM: To investigate the effect of proteinase activated receptorª²2 (PARª²2) agonists on histamine and tryptase release from human skin and tonsil mast cells. METHODS: Enzymatically dispersed mast cells from human skin and tonsil were challenged with PARª²2 stimuli and tryptase and histamine release were determined. RESULTS: PARª²2 agonist peptide SLIGKV induced the release of histamine, but not that of tryptase from skin mast cells. However, it induced the release of tryptase, but not that of histamine from tonsil mast cells. Another PARª²2 agonist peptide tcª²LIGRLO appeared less potent than SLIGKV in induction of release of histamine and tryptase. CONCLUSION: We are the first to report the in vitro tryptase release properties of human skin and tonsil mast cells. The differences in release of tryptase and histamine from skin and tonsil mast cells suggest a novel type of mast cell heterogeneity in response to stimulation, and indicate that there might be at least two selfª²amplification mechanisms of degranulation in human mast cells. ......