Mononuclear cells, mast cells and mucous cells as part of the delayed hypersensitivity response to aerosolized antigen in mice.

Mice (BALB/c) exposed to picryl chloride (PiCl) on their shaved abdomen and untreated animals were after 7 days exposed to daily aerosolized trinitrophenylated dog serum albumin (TNP-DSA). Mice exposed to PiCl tended to respond earlier and more strongly with both delayed hypersensitivity (DH) and IgG antibodies in serum and bronchial washings than did mice exposed to aerosol only. Picryl chloride sensitization resulted in spontaneously proliferating axillary lymph node cells, which could not be further stimulated with antigen or mitogen. Histological examination of lung tissue of aerosol-sensitized animals revealed an increase in mononuclear cells and mast cells around bronchioli and mucous cells, particularly in those animals exposed for prolonged periods and sensitized with PiCl prior to aerosol. Sensitization of mice with aerosolized TNP-DSA administrated in two 2- and 1-week periods with a 4-week interval responded with DH and IgG antibody in a dose dependent fashion irrespective of presensitization with PiCl. In bronchial washings IgG antibodies were found particularly after two 2-week periods of exposure. The cells taken from the axillary or brachial lymph nodes showed spontaneous proliferation. Culture of the cells to achieve mast cell maturation resulted in no or very low numbers of mast cells in the lymph nodes.