Analysis of pgf 54 Members in Lyme Disease Serodiagnosis

描述（由申请人提供）：莱姆病的病原体伯氏疏螺旋体维持在一个感染周期中，该周期涉及细菌从硬蜱传播到哺乳动物宿主。在传播过程中，螺旋体遇到环境刺激的许多变化，并通过修改可能在适应、感染和持久性中被证明是重要的基因的表达来对环境中的这些变化作出反应。许多差异表达的基因存在于可以从该螺旋体分离的许多线性（lp）和环状（cp）质粒上。迄今为止，许多这些pH和温度调节膜蛋白的功能尚未确定。感兴趣的是定位于质粒lp54的旁系同源基因家族（pgf）54的几个成员，当螺旋体暴露于模拟附着的、进食的蜱或哺乳动物的环境的温度和pH（37 ℃和pH7.0）时，所述旁系同源基因家族在体外上调。同样地，这些pgf 54成员中的许多成员在模拟自由生活、未进食的蜱的实验室条件（23 ℃和pH 8.0）下下调。此外，我们已经确定，血清感染的小鼠通过蜱传播识别十九疏螺旋体膜蛋白，其中两个成员的pgf 54。在具体目标1中，我们打算评估使用由pgf 54成员编码的蛋白质作为早期、早期播散性和晚期莱姆病的诊断标志物。在具体目标2中，我们将确定使用由pgf 54编码的重组蛋白作为疫苗候选物的功效。此外，在特定目标3中，我们将鉴定由B表达的其他pH调节膜蛋白。在蜱传感染的小鼠中检测伯氏螺旋体，这可能具有诊断意义。

DESCRIPTION (provided by applicant): Borrelia burgdorferi, the etiologic agent of Lyme disease, is maintained in an infectious cycle that involves the transmission of the bacterium from an Ixodes tick to a mammalian host. During transmission the spirochetes encounter numerous alterations in environmental stimuli, and respond to these alterations in the environment by modifying the expression of genes that may prove important in adaptation, infection and persistence. Many of the genes that are differentially expressed reside on the many of the linear (lp) and circular (cp) plasmids that can be isolated from this spirochete. To date, the function of many of these pH and temperature-regulated membrane proteins has not been determined. Of interest are several members of paralogous gene family (pgf) 54 that localize to plasmid lp54 that are up-regulated in vitro when spirochetes are exposed to a temperature and pH (37 degrees C and pH 7.0) that mimic the environment of the attached, fed tick or mammal. Likewise, many of these pgf 54 members are down regulated by laboratory conditions that mimic the free-living, unfed tick (23 degrees C and pH 8.0). Moreover, we have determined that sera from mice infected via tick-borne transmission recognize nineteen borrelial membrane proteins, two of which are members of pgf 54. In Specific Aim 1 we intend to assess using the proteins encoded by the pgf 54 members as diagnostic markers of early, early-disseminated, and late stage Lyme disease. In Specific Aim 2 we will determine the efficacy of using recombinant proteins encoded by pgf 54 as vaccine candidates. Furthermore, in Specific Aim 3 we will identify additional pH-regulated membrane proteins expressed by B. burgdorferi during tickborne infection of mice that may be of diagnostic interest.