151 In vitro model of eosinophil migration into the site of acute allergic reactions

Abstract

PEROXIDE GENERATION BY EOSINOPHIS IN ALLERGIC RHINITIS. H.Oqasawara,M.D.,S.Yoshimura, M.D. and T.Kumoi,M.D.,Nishinomiya,Japan We previously showed that H202 which could be produced by eosinophils or neutrophils from peripheral blood itself induced histamine release ,and that low concentration of H202 augmented anti-IgE or antigen mediated histamine release, while high concentration of H202 which were not cytotoxic inhibited anti-IgE or antigen mediated histamine release. The function of eosinophils in nasal secretions or peripheral blood in house dust nasal allergic patients was studied. Nasal secretion were collected, soon the patient were challenged with house dust, and 5,15 and 30 minutes later respectively,additional nasal secretion were collected. Leukocytes were isolated using five different concentrations(50,56,64,68 and 72%)of Percoll solution from heparinized venous blood. After nasal challenge,the population of eosinophils was increased with various times elapsed to 47,64,65 and 73%,the concentration of H202 in nasal secretion was B&739,728 and 697 pmol/g,the activity of peroxidase was 0.90,0.65,1.67 and 0.91 microgram/g respectively, and the activity of arylsulfatase was not change during this time. Eosinophi chemotactic activity was seen in 5 minute nasal secretion. The generation of H202 increased with time elapsed;stimulation with zymosan enhanced the H202 generation. The rate of phagocytosis for zymosan in eosinophils was not changed. In the high IgE group, oxidative metabolic function in eosinophils from peripheral blood was higher than in the low IgE group. Eosinophil chemotactic activity seemed to stimulate oxidative metabolic function. H202 plays a significant role in vivo was suggested.