Effects of Endotoxin on Macrophages and Other Lymphoreticular Cells

In addition to exerting an adjuvant effect by direct stimulation of bone-marrow (B) lymphocytes, Escherichia coli endotoxin appears to have an adjuvant effect involving macrophages and thymus (T) lymphocytes. In cultured macrophages endotoxin stimulates the synthesis of the nonlysosomal enzymes lactic dehydrogenase and leucine-2-naphthylamidase (which are retained in the cytoplasm) and of the lysosomal enzymes acid phosphatase and β-N-acetylglucosaminidase(which are released into the medium). Properties of antibody-dependent cytotoxic lymphoid cells are discussed in relation to possible effects in endotoxin-mediated, immunopathologic reactions.