The cytotoxic effect in delayed-type hypersensitivity on autologous adherent cells (macrophages) of lymph nodes and spleen

Abstract

Cytotoxic effect (CE) on the lymph node and spleen adherent cells (macrophages) used as target cells was investigated in vitro in delayed-type hypersensitivity (DTH) to BCG and streptococcal group A antigens. Pronounced CE has been found on lymph node macrophages in the system containing autologous lymphocytes and corresponding antigens. Relatively lower CE on autologous splenic macrophages was not due to their greater resistance since addition of sensitized autologous or allogeneic lymph node lymphocytes resulted in a high level of cytotoxicity. It is suggested that death of macrophages of lymphoid organs might occur in vivo during DTH, and result in impairment of the immunoregulatory function of macrophages. The possibility of participation of lysosmal enzymes of macrophages and the significance of increased permeability of lysosomal membranes in the cytotoxic effect are discussed. Determination of the CE on macrophages of lymphoid organs in the autologous system in vitro can be used as a simple and demonstrable method for detection of DTH in experimental animals.