This project is designed to study local and systemic, humoral and cellular immunological responses in the lung of the rabbit following inhalation of antigen. Immunogenic requirements for hypersensitivity lung disease will be investigated as will immmunologic accompaniments of disease and of defense. Antigen-specific antibodies of individual immunoglobulin classes will be determine by an amplified enzyme-linked immunosorbent assay (ELISA) and by precipitin quantitation. Localization of immunoglobulins and antibodies will be studied by immunofluorescence techniques in lung, lymph nodes and other tissues. Cellular responses will include antigen-specific release of lymphokines (e.g. MIF), cytotoxicity, and chemotactic assays. These studies are expected to increase understanding of immunogenic requirements, pathogenesis and protective mechanisms in this model and potentially in human inhalational lung diseases.