Regional and systemic immune responses to trinitrophenyl derivatives after intranasal and subcutaneous sensitization of mice.

The immune responses and accompanying inflammatory local reactions were analyzed in mice sensitized subcutaneously (SC) or intranasally. Administration of picrylsulfonic acid (PSA) by both routes for two 2- or 1-week periods with a 4-week interval resulted in delayed hypersensitivity responses. Serum antibodies of the IgG and IgE and some of the IgA isotype were found, particularly in SC-sensitized animals. The latter animals also had levels of IgG antibodies in their bronchial fluid. Lymph node cells from mice sensitized for 2-week periods demonstrated high spontaneous proliferation. After culture together with spleen cells, these cells exhibited considerable numbers of mast cells, particularly after stimulation with pokeweed and antigen. The lungs from mice sensitized intranasally revealed increased numbers of mononuclear cells around large vessels and mucous cells in the bronchiolar epithelium, although there were individual differences between the animals. The mast cell numbers in the lungs were only slightly increased compared with numbers in nonimmunized animals subjected to ether anesthesia. Animals injected SC with PSA exhibited increased numbers of mast cells in their lungs compared with control mice. Mice sensitized with trinitrophenylated human serum albumin demonstrated some differences in their immune reactivity compared with animals immunized with PSA. Thus, no obvious delayed hypersensitivity appeared, but the IgG antibody titers were higher, and the IgE antibody titers were lower. The cellular responses assessed histologically demonstrated higher mononuclear cell numbers and lower mast cell numbers compared with those observed in animals sensitized with PSA.(ABSTRACT TRUNCATED AT 250 WORDS)