LYMPHOCYTE-ACTIVATION BY HOUSE DUST ALLERGEN IN ASTHMA - ANALYSIS WITH MONOCLONAL-ANTIBODIES

Peripheral blood mononuclear cell (MNC) response to house dust (HD) stimulation in cultures was studied in a group of 35 subjects with asthma and a multiple positive skin test (ST) reaction to inhalant allergens including HD, and in 19 healthy controls. The MNC response to allergen stimulation was assessed by interleukin‐2 receptor (IL‐2R) expression identified with an anti‐Tac monoclonal antibody. Lymphocyte subpopulations of baseline and cultured cells were also analysed. The percentage of IL‐2R presenting cells increased significantly in HD‐driven cultures in the asthma group compared to controls. The increase in proportion of IL‐2R+ cells was closely related to the increase in CD4+ percentage of cultured cells and was accompanied by a decrease in proportion of CD8+ lymphocytes and monocytes/macrophages, suggesting that HD‐activated cells were CD4+ lymphocytes. Lymphocyte activation, measured by IL‐2R expression, was significantly higher in the group of asthmatics, and positive dual (early and late) skin reaction to HD, as compared to those with single early reaction. Copyright © 1990, Wiley Blackwell. All rights reserved