T-CELLS EXPRESSING VARIABLE ELEMENTS OF T-CELL RECEPTOR BETA-8-CHAIN AND BETA-2-CHAIN REGULATE MURINE IGE PRODUCTION

After sensitization to ovalbumin (Ova) by inhalation of nebulized antigen, BALB/c mice respond with an early rise in IgE but not in IgG anti-Ova antibody production. Our purpose here was to analyze the repertoire of T cells that may contribute to regulating this IgE response. Initial study of Ova-reactive T-cell hybridomas showed that they selectively express the T-cell receptor variable beta-chain (V(beta)) elements 2, 8.1/8.2, and 14. The frequency of T cells bearing these V(beta) elements in local draining lymph nodes of the airways and lungs (peribronchial-draining lymph nodes) after Ova inhalation was examined. Local sensitization increased the proportion of V(beta-8.1/8.2) T cells in the peribronchial-draining lymph nodes, whereas expression of V(beta-2) or V(beta-14) was similar in sensitized and nonsensitized animals. In the presence of increased antigen concentrations, V(beta-8) and V(beta-2) T cells were equally reactive to Ova when cell proliferation was assayed. Coculture of Ova-selected V(beta-8) T cells from peribronchial-draining lymph nodes and spleens of sensitized animals with primed splenic B cells increased IgE but not IgG production. The V(beta-8) increase in IgE production was related to an increase in numbers of IgE-secreting B cells. In contrast, coculture of Ova-selected V(beta-2) T cells with sensitized B cells had no stimulatory effect on either IgE or IgG production. Further, addition Of V(beta-2) cells to V(beta-8) cells inhibited the V(beta-8)-induced augmentation of IgE production. These data indicate that T cells expressing different T cell receptors or, perhaps, different V(beta) elements may play different roles in IgE production in sensitized mice.