Cellular inflammatory responces in human allergic skin reactions

Abstract To define better the role of inflammation in the response to pollen antigens, we have used our skin chamber model to study inflammatory cells recovered from the sites of ongoing allergic reactions. In 15 atopic subjects, paired skin blister sites were simultaneously challenged with ragweed- or grass-pollen antigen or buffer for 5 hours. There were 10 times as many cells recovered at antigen (20.7 × 10 5 ) than at buffer (20 × 10 5 ) sites, p 97% of the cells recovered were neutrophils. The number of cells recovered at the antigen sites correlated with the total amount of histamine released (r = 0.57; p N -formyl-methionyl-leucyl-phenylalanine, or leukotrine B 4 , but there was a significantly decreased response to platelet-activating factor when the cells recovered from antigen sites were compared to autologous blood neutrophils. We conclude that during ongoing allergic cutaneous reactions (1) that we can recover a significantly greater number of neutrophils at antigen than at buffer sites, (2) that these cells are capable of chemotaxis and phagocytosis, (3) that these neutrophils appear morphologically different from neutrophils in the peripheral blood, and (4) that the number of neutrophils recovered correlates with the intensity of the ongoing mast cell response as assessed by mediator release.