Sensitizing ability of derivatives of picryl chloride after exposure of mice on the skin and in the lung.

Abstract

In the present study the immunizing efficacy of antigen or hapten administered by the respiratory route and the resulting inflammatory reactions in the lungs after challenge were studied. We compared the induction of delayed hypersensitivity (DH) and the IgG, IgM, IgA, and IgE antibody formation after immunization with three different trinitrobenzene derivatives by the epicutaneous, the intradermal, and the intraperitoneal routes with the intranasal route. Mice sensitized with picryl chloride (PiCl) epicutaneously or intradermally, or with picryl sulfonic acid (PSA) epicutaneously showed strong DH responses. Moderate DH responses were obtained after sensitization with PSA intradermally and with trinitrophenylated human serum albumin (TNP-HSA) intraperitoneally. Intranasal administration of PSA and TNP-HSA also resulted in moderate DH responses. Strong IgG responses were seen in mice sensitized with PiCl and PSA epicutaneously, intradermally, and also intranasally. Administration of TNP-HSA epicutaneously, intradermally, and intraperitoneally also gave high IgG responses, while intranasal administration only induced moderate ones. Considerable IgM responses were seen only in mice sensitized epicutaneously with PSA. Antibody responses of the IgA isotype were only seen after epicutaneous sensitization with PiCl or PSA and intradermally with PiCl. Histological examination of lung tissue from mice sensitized with PiCl epicutaneously or with PSA intranasally and challenged with PSA intranasally revealed some inflammatory cells around bronchioli, capillaries and in the interstitial tissue. Differentiation of mucous cells in the epithelium covering inflammatory cells was also seen, and a slight increase in mast cell numbers around vessels. However, after sensitization with PiCl epicutaneously, TNP-HSA intranasally, and challenge with 2% TNP-HSA intranasally, a weaker inflammation was seen. In conclusion, intranasal administration of PSA or epicutaneous administration of PSA and PiCl gave strong DH and IgG responses. These sensitization regimes also resulted in pronounced inflammatory reactions in the lungs.