SURFACE ANTIGENS OF TREPONEMA PALLIDUM

梅毒是由梅毒螺旋体引起的，仍然是一个重大的公共卫生问题，并已被证明会加剧艾滋病毒的传播。需要有预防梅毒的新手段，包括研制疫苗。为了合理地进行疫苗开发，必须根据抗原在发病机制和免疫方面的功能对其进行优先检查。抗体对T. pallidum的调理对于细菌清除和巨噬细胞介导的杀伤至关重要。因此，我们将筛选与opsonic兔血清（ORS）反应的重组表达文库。ORS是兔免疫血清，其中吸附了许多“无关”抗体（对调理不重要的抗体，包括针对主要脂蛋白和鞭毛的抗体）；吸附后保留完整的声速容量。根据对非抗血清（抗疏螺旋体、抗钩端螺旋体）缺乏反应性，将优先选择克隆进行进一步检查。将对有希望的克隆进行测序，并在新发布的T. pallidum基因组序列中确定其完整的开放阅读框（orf）。orf将以重组蛋白的形式表达，并产生抗体。这些抗体将被用来确定抗原是否位于苍白球绦虫的表面。这些分子在白球绦虫附着于真核细胞中的作用，是发病机制的早期步骤，将通过测试抗体在体外阻断粘附的能力来检验。我们将通过检测抗血清促进兔腹腔巨噬细胞吞噬苍白球绦虫的能力来研究抗原在活化中的作用。基于其表面定位或其在活化或细胞粘附方面的作用，似乎有希望的抗原将被测试其保护兔子免受苍白t病毒攻击的能力。基于已知在发病机制和免疫中重要的功能，这种选择感兴趣抗原的重点方法将确定白螺旋体的重要毒力因素，并将确定潜在的候选疫苗以供进一步研究。

Syphilis, caused by Treponema pallidum, continues to be a significant public health problem and has been demonstrated to augment the spread of HIV. New means of prevention of syphilis, including vaccine development, are needed. In order to approach vaccine development in a rational way, antigens must be prioritized for examination based upon their functions in pathogenesis and immunity. The opsonization of T. pallidum by antibodies is crucial for bacterial clearance and for macrophage-mediated killing. Therefore, a recombinant expression library will be screened for clones reacting with opsonic rabbit serum (ORS). The ORS is immune rabbit serum from which many "irrelevant" antibodies (those not important for opsonization, including antibodies to the major lipoproteins and the endoflagella) have been adsorbed; full opsonic capacity is retained following adsorption. Selected clones will be prioritized for further examination based upon their lack of reactivity with non-opsonic antisera (anti-Borrelia, anti-Leptospira). Promising clones will be sequenced and their full open reading frames (ORFs) will be identified in the newly released T. pallidum genome sequence. The ORFs will be expressed as recombinant proteins and antibodies will be produced. These antibodies will be used to determine if the antigens are located on the surface of T. pallidum. The role of these molecules in attachment of T. pallidum to eucaryotic cells, an early step in pathogenesis, will be examined by testing the ability of the antibodies to block adherence in vitro. The role of the antigens in opsonization will be examined by testing the antisera for their ability to facilitate phagocytosis of T. pallidum by rabbit peritoneal macrophages. Antigens that appear to be promising, based upon in their surface localization or their role in opsonization or cytoadherence, will be tested for their ability to protect rabbits from challenge with T. pallidum. This focused approach for selecting antigens of interest, based upon functions known to be important in pathogenesis and immunity, will identify important virulence factors of T. pallidum and will identify potential vaccine candidates for further study.