Booster-Dependent Alterations of the Subsets of T Lymphocytes and Eosinophils in the Bronchi of Immunized Guinea Pigs.

Abstract

We investigated whether guinea pigs sensitized to ovalbumin show changes in T cells in the bronchial wall and whether they correlate with eosinophil migration. Animals received two injections of 10 µg ovalbumin in Al(OH)3 with a 2-week interval. Lungs were resected and frozen and cryostat sections stained with monoclonal antibodies recognizing T cells and subsets. Eosinophil peroxidase staining was used to identify this cell type. Sections stained with each marker were read 'blind' and cells enumerated in the bronchial lamina propria. A large number of T cells, mainly of CD4+ subset, were recruited into the bronchi 7 days after the booster injection of the antigen, in contrast to nonimmunized or nonboosted animals. These changes were also accompanied by an infiltration of eosinophils in boosted animals and suggest that T cells and/or their products play an important role in the development of bronchial hyperreactivity in this model.