Purification and characterization of human skin mast cells. Evidence for human mast cell heterogeneity

Our previous studies of human lung and intestinal mast cell failed to show the heterogeneity found among mast cells in murine species. Recently, we and others have deveoped techniques for the enzymatic dispersion of human neonatal skin mast cells. In addition, we are now able to make single cell suspensions of mast cells from adult skin and to purify these cells to near homogeneity. Comparative studies of mast cells from these several sources have uncovered several major differences among them. Adult and neonatal skin mast cells themselves differ in that the former ar 10-fold less sensitive to goat anti-human IgE, with maximal release occuring at 3.0 and 0.3 μg/ml, respectively. Skin mast cells also differ in optimal temperature for release: adult mast cells respond maximally at 23 to 30°C and neonatal cells at 37°C. Skin mast cells from both sources are dramatically different from lung and intestinal mast cells in two aspects. First, skin mast cells are quire responsive to several stimuli - morphine sulfate (10^-4 to 10^-6 M), substance P (10^-5 to 10^-7 M), compound 48/80 (10 to 0.1 μg/ml), f-Met peptide (10^-6 M), and C5a (10^-8 M) - to which the other mast cells fail to respond. Second, although stimulated skin mast cels produce prostaglandin D₂, little leikotriene C₄, if any, is generated, unlike lung or intestinal mast cells. These differences in inflammatory potential among human mast cells from various sites have important implications for the management of allergic inflammatory responses.