Marshall N E, Ziegler H K
Department of Microbiology and Immunology, Emory University School of Medicine, Atlanta, Georgia 30322.
Infect Immun. 1989 May;57(5):1556-60. doi: 10.1128/iai.57.5.1556-1560.1989.
Lipopolysaccharide (LPS), a major component of the outer membrane of gram-negative bacteria, is known to be a potent modulator of many host immune functions, including the expression of products of the class II major histocompatibility locus (Ia molecules) by macrophages. LPS-mediated Ia induction is controlled by the lps gene. We sought to determine the role of LPS in the induction of Ia expression during infection with gram-negative bacteria. To address this question, we tested a simple prediction: if LPS is the primary determinant of Ia induction during gram-negative infection, then the Ia response to intraperitoneal injection of these organisms should be under the control of the lps gene. We found that while both LPS-responder and LPS-low-responder mice showed strong Ia responses to injection of either a gram-positive bacterium (Listeria monocytogenes) or concanavalin A, only the LPS-responder mice responded strongly to gram-negative organisms or to LPS alone. We interpret these results as strong evidence for the role of LPS as the primary determinant of Ia induction by gram-negative bacteria.
脂多糖（LPS）是革兰氏阴性菌外膜的主要成分，已知它是许多宿主免疫功能的有效调节剂，包括巨噬细胞对II类主要组织相容性位点产物（Ia分子）的表达。LPS介导的Ia诱导由lps基因控制。我们试图确定LPS在革兰氏阴性菌感染期间Ia表达诱导中的作用。为了解决这个问题，我们测试了一个简单的预测：如果LPS是革兰氏阴性菌感染期间Ia诱导的主要决定因素，那么腹腔注射这些细菌后Ia的反应应该受lps基因的控制。我们发现，虽然LPS反应者和LPS低反应者小鼠对注射革兰氏阳性菌（单核细胞增生李斯特菌）或伴刀豆球蛋白A均表现出强烈的Ia反应，但只有LPS反应者小鼠对革兰氏阴性菌或单独的LPS有强烈反应。我们将这些结果解释为LPS作为革兰氏阴性菌诱导Ia的主要决定因素的有力证据。
