Schafer R, Eisenstein T K
Department of Microbiology and Immunology, Temple University School of Medicine, Philadelphia, Pennsylvania 19140.
Infect Immun. 1992 Mar;60(3):791-7. doi: 10.1128/iai.60.3.791-797.1992.
We have previously shown that an avirulent strain of Salmonella typhimurium, SL3235, blocked in aromatic synthesis, confers high levels of resistance to challenge with virulent Salmonella as early as 3 days postvaccination. In the present studies, it was found that immunization with SL3235 resulted in high levels of natural killer (NK) cell activity in the spleens and peritoneal cavities of C3H/HeJ mice, as measured by cytotoxicity against YAC-1 targets. NK cell activity was at its maximum 2 to 4 days after immunization and was ablated by in vivo or in vitro treatment with anti-asialo GM1. In vivo treatment with anti-asialo GM1 during the first week after immunization with SL3235 depleted NK cell activity and markedly increased mortality in mice challenged with a virulent Salmonella strain. These results are compatible with a role for NK cells as one important component in the resistance against virulent Salmonella infection induced by a live, attenuated vaccine.
我们先前已表明，一株在芳香族合成中受阻的鼠伤寒沙门氏菌无毒株SL3235，早在接种疫苗后3天就能使机体对有毒力的沙门氏菌攻击产生高水平的抗性。在本研究中，发现用SL3235免疫可导致C3H/HeJ小鼠脾脏和腹腔中的自然杀伤（NK）细胞活性升高，这是通过对YAC-1靶标的细胞毒性来测定的。NK细胞活性在免疫后2至4天达到最大值，并通过用抗唾液酸GM1进行体内或体外处理而被消除。在用SL3235免疫后的第一周内，用抗唾液酸GM1进行体内处理可耗尽NK细胞活性，并显著增加受到有毒力沙门氏菌菌株攻击的小鼠的死亡率。这些结果与NK细胞作为由减毒活疫苗诱导的抗有毒力沙门氏菌感染抗性的一个重要组成部分的作用相符。
