POLYADENYLIC ACID POLYURIDYLIC ACID (POLY A-U) AND EXPERIMENTAL MURINE BRUCELLOSIS .2. MACROPHAGES AS TARGET-CELLS OF POLY A-U IN EXPERIMENTAL BRUCELLOSIS

  • 1 January 1978
    • journal article
    • research article
    • Vol. 35  (1) , 77-84
Abstract
Results of in vivo and in vitro experiments suggest that the early suppression of Brucella growth in double stranded poly A:U) treated mice was due to a non-specific activation of macrophages by poly A:U. Poly A:U administered i.p. at the time of Brucella infection failed to enhance T[thymus derived]-cell mediated responses to the organism, namely delayed-type hypersensitivity to brucellin and adoptive transfer of immunity to the infection. Poly A:U did not augment the protective antibodies formed in response to infection. Although poly A:U was previously found to suppress brucellosis in athymic (nude) mice, it did not enhance the thymus-dependent antibody response to sheep erythrocytes in Brucella-infected nudes, suggesting that it did not significantly enhance maturation of their helper T-cell percursors. Increased macrophage spreading, an indication of activation, was seen immediately after administration of poly A:U and Brucella abortus. Later on the infection spreading was suppressed, a phenomenon which appears to relate to the biphasic effect of poly A:U in vivo. Peritoneal macrophages treated in vitro with poly A:U were stimulated to spread on plastic surfaces, even when T lymphocytes were removed with anti-Thy-1 serum and complement.