新的梅毒螺旋体基因分型系统的建立及其在神经梅毒诊断中的应用

The specific diagnostic indicators for neurosphilis is still deficiency at present. The rate of missed diagnosis and misdiagnosis of neurosyphilis is quite high. Studies have shown that some Tp genotypes may be related to the pathogenesis of neurosyphilis. Our preliminary studies found that Tp from cerebrospinal fluid of neurosyphilis patients was more resistant to the removal of phagocytic cells than Tp from chancre lesions of acute syphilis patients. We guess that a quite number of neurosyphilis are caused by "neurotropic" strains, and this related Tp subtype testing is expected to become a new method for diagnosis of neurosyphilis. The CDC subtype/tp 0548 sequence type genotyping system will be adopted in this project to obtain the "neurotropic" strains; By combination of the differential genes detected by the full gene sequence analysis and the "neurotropic" genes selected by CDC subtype/ tp 0548 sequence type genotyping system, new target genes will be screened out, then it will be regarded as an important marker for diagnosis of neurosyphilis, In addition, a new genotyping method will be designed at the same time. After "neurotropic" Tp subtype information was verified by methodology, the application values for the diagnosis of neurosyphilis, discriminate between relapse and reinfection, as will as lumbar puncture pointer will be discussed. This project makes a research on the present difficult and blind zone for the diagnosis of neurosyphilis from a new perspective. It is expected to make a major contribution to the breakthrough of Tp study.

目前缺乏神经梅毒特异性诊断指标，漏诊和误诊率高。研究发现某些基因型别梅毒螺旋体（Tp）可能与神经梅毒发生有关，我们前期研究也发现神经梅毒患者脑脊液来源的Tp比急性梅毒患者硬下疳来源的Tp更能抵抗吞噬细胞的清除。猜测相当数量的神经梅毒是由亲神经亚型的Tp感染所致，其检测有望成为神经梅毒诊断的新手段。本项目采用CDC subtype/tp0548 sequence type基因分型系统，获得我国神经梅毒优势亚型；采用全基因序列分析发现该亚型差异基因，结合已有的分型系统所选基因，筛选出特异的亲神经亚型的靶基因，以此作为神经梅毒诊断的一个重要标志物，建立新的基因分型方法；经方法学验证后，探讨新基因分型在神经梅毒的诊断、鉴别梅毒的复发与再感染，以及提供腰部穿刺指征等方面应用价值。本项目从全新的角度研究当前有关神经梅毒诊断的难点和盲区，有望产生重要的突破。

本项目首先采用CDC subtype/Tp0548 sequence type分型系统，初筛神经梅毒的优势分子分型Tp株，然后经全基因序列分析查找其差异分子靶标，获得16sDNA作为神经梅毒的靶标，结合已有分型法的被检基因信息，建立CDC subtype/Tp0548 sequence type/16s DNA分子分型方法，用于神经梅毒的诊断，其灵敏度为66.67%，特异性为65.22%；从全新的角度揭示神经梅毒的发生机制，为神经梅毒早期诊断提供预警指标，为临床专科医生及早进行治疗干预处理提供科学依据；本项目获得发明专利2项；发表论文16篇，其中SCI论文15篇，培养青年教师1名，培养硕士生4名，2名获得国家奖学金，参加学术交流2次，较好地完成了课题任务。