梅毒螺旋体及其相关蛋白与不同宿主细胞相互作用的研究进展

梅毒是由梅毒螺旋体引起的性传播疾病,可造成全身多脏器损害。梅毒螺旋体致病机制涉及暴露、黏附/定植、侵袭/感染、播散等过程。在这些过程中梅毒螺旋体与宿主细胞存在长期的相互作用,病原体本身及其相关蛋白的致病性与宿主的免疫防御间的平衡在相互作用中扮演重要角色。本文就梅毒螺旋体及其相关蛋白与不同宿主细胞相互作用的研究进展综述如下。     

梅毒免疫和梅毒螺旋体的研究进展

梅毒螺旋体有着独特的基因和蛋白结构,对其基因分型有利于梅毒分子流行病学的研究.梅毒螺旋体缺乏脂多糖与外膜蛋白,但可表达多种脂蛋白,这些脂蛋白同梅毒螺旋体的组织黏附及播散有关,同时可诱导机体发生免疫应答.机体对于梅毒螺旋体的免疫应答过程十分复杂,固有免疫、体液免疫及细胞免疫均在梅毒螺旋体的感染过程中参与了应答过程.Th1型细胞免疫在梅毒的发生发展过程中起重要作用,梅毒患者在局部及系统免疫方面都存在细胞免疫的异常.     

梅毒血清固定相关免疫学机制的研究进展

梅毒是由梅毒螺旋体感染引起的一种慢性全身播散性传染病.多数患者经过正规驱梅治疗后,梅毒血清反应素抗体滴度可转阴.但仍有部分患者梅毒血清反应素抗体滴度下降至一定水平后不再变化,即梅毒血清固定.形成这一现象的机制尚不完全清楚.近年来的研究显示,梅毒血清固定与患者的免疫机能密切相关,可能涉及T细胞减少,CD4＋CD25＋Treg表达上调,Treg和Th17细胞的平衡偏移,CD80/CD86表达下调以及天然免疫中Toll样受体2 mRNA、自然杀伤细胞下调等诸多因素.梅毒血清固定已成为临床驱梅治疗中面临的困惑与疑难问题之一,揭示梅毒血清固定的发生机制对梅毒有效防治具有重要意义.     

神经梅毒与AIDS/HIV阳性

梅毒螺旋体可侵犯中枢神经系统引起神经梅毒,神经梅毒的临床表现多变、缺乏特征性,容易误诊。随着人类免疫缺陷病毒(H IV)的播散,获得性免疫缺陷综合征(AIDS)/H IV(+)合并神经梅毒的病例屡有报道。AIDS/H IV(+)对神经梅毒产生影响,使神经梅毒在发病机制、发病率、临床表现、实验室检查、治疗及随访等方面与H IV(-)的神经梅毒有所不同。     

二期梅毒误诊3例分析

二期梅毒皮肤损害，是梅毒螺旋体由局部经淋巴结进入血液，在人体内大量播散后而出现的全身表现，可与很多其它疾病的表现相像，早期常易误诊误治，现报告3例如下：     

名词解释

梅毒(syphilis)是由梅毒螺旋体引起的一种慢性、系统性性传播疾病。人体受感染后,螺旋体很快播散到全身,几乎可侵犯全身各组织与器官,临床表现多种多样,且时显时隐,病程较长。早期主要侵犯皮肤及黏膜,晚期除侵犯皮肤黏膜外,还可侵犯心脏血管系统及中枢神经系统;另一方面,梅毒又可多年无症状呈潜伏状态。梅毒主要通过性接触传染,梅毒孕妇可通过胎盘传染胎儿,导致流产、早产、死胎或分娩先天梅毒儿;亦可因输入梅毒患者血液而受感染。名词解释     

细胞免疫机理在埃塞俄比亚梅毒患者中的作用

在感染梅毒时,由于螺旋体能进入细胞内,从而免受循环抗体的作用,这也和分枝杆菌、利什曼原虫等其他细胞内微生物感染一样,细胞免疫可能起重要作用。对实验梅毒兔给以抑制细胞免疫而不影响抗体产生的免疫抑制剂,可使原应限局于接种部位的损害,变为更严重和播散。作者观察了107例埃塞俄比亚梅毒患者的细胞     

扫描电镜下梅毒螺旋体超微结构及其对宿主细胞表面的损害

为研究梅毒螺旋体超微结构及其对宿主细胞表面的损伤作用,对13例早期梅毒患者扁平湿疣损害的上皮细胞进行冷冻割断处理,应用扫描电镜对其进行了观察。在扫描电镜下:每条梅毒螺旋体呈7～12个螺旋,每个螺旋的投影波长为0.6～1.2μm,振幅0.15～0.3μm.梅毒螺旋体两端轴长7.0～13.0μm,其在扫描电镜下投影的体轴为8.3～22.0μm,梅毒螺旋体两端的轴长与体轴之比为1:1.2～1.9.梅毒螺旋体横断面直径约0.16μm.在经冷冻割断处理的宿主细胞表面可见粘附着大量的梅毒螺旋体,在一幅扫描电镜观察面见宿主细胞胞膜附着20多条梅毒螺旋体。粘附梅毒螺旋体的宿主细胞胞膜见大小不等的小孔。梅毒螺旋体粘附宿主细胞表面,使得宿主细胞膜被破坏,由此产生一系列组织和细胞的病理变化。     

神经梅毒

神经梅毒 (Neurosyphilis,NS)是梅毒螺旋体 (Treponemapallidum ,Tp)在全身系统性播散的同时侵犯脑膜和 (或 )血管引起神经组织变性或血管病变的一种慢性中枢神经系统疾病。随着我国梅毒发病率逐年上升 ,艾滋病进入快速增长期 ,神经梅毒也开始复活。鉴于此 ,有必要对神经梅毒的诊断及治疗等相关问题进行复习。1　诊断　　神经梅毒的发病是螺旋体活力和宿主免疫力之间的相互作用的结果。研究表明 :二期梅毒患者中出现脑脊液异常 (包括细胞计数增多、蛋白含量升高、VDRL(+ )或活性Tp检测 (+ )可高达 4 0 % ,然而仅不足 1 -2 %者有中枢神经…     

梅毒螺旋体对人脑微血管内皮细胞趋化因子配体6、8、10表达的影响

目的 探讨梅毒螺旋体对人脑微血管内皮细胞（HBMEC）趋化因子配体（CXCL）表达的影响。方法 将培养的HBMEC分为4组,分别加入用细胞培养液稀释的有活性的梅毒螺旋体、灭活的梅毒螺旋体、脂多糖和细胞培养液（梅毒螺旋体组、灭活梅毒螺旋体组、脂多糖组和空白对照组）刺激6、12、24 h,用荧光定量PCR和酶联免疫吸附试验分别检测细胞中CXCL6、CXCL8和CXCL10基因和蛋白表达水平。利用Transwell小室细胞迁移实验检测梅毒螺旋体刺激后HBMEC对人早幼粒细胞白血病细胞HL-60的趋化作用。结果 在各时间点,梅毒螺旋体组HBMEC中CXCL6、CXCL8和CXCL10的mRNA表达水平均显著高于空白对照组和灭活梅毒螺旋体组（P＜0.05）,而灭活梅毒螺旋体组与空白对照组之间差异无统计学意义（均P＞0.05）。和脂多糖组相比,梅毒螺旋体组的CXCL6和CXCL8 mRNA表达降低（P＜0.05）,CXCL10差异无统计学意义（P＞0.05）。在各时间点,梅毒螺旋体组HBMEC培养上清液中CXCL6和CXCL8含量均高于空白对照组和灭活梅毒螺旋体组（均P＜0.05）,而后2组间差异无统计学意义（均P＞0.05）。各时间点培养上清液中CXCL10含量在梅毒螺旋体组、灭活梅毒螺旋体组和空白对照组间差异无统计学意义（均P＞0.05）;梅毒螺旋体组Transwell小室下室中迁移的HL-60细胞数量（A570）均高于另2组（均P＜0.05）。结论 有活性的梅毒螺旋体可上调HBMEC中CXCL6、CXCL8和CXCL10基因表达水平,增加CXCL6和CXCL8的分泌,增强HBMEC对HL-60细胞的趋化作用,这可能在神经梅毒的发病中起一定作用。     

聚合酶链反应对一期梅毒患者的诊断

目的:建立聚合酶链反应(PCR)用于快速检测梅毒螺旋体。方法:根据梅毒螺旋体47ku膜蛋白基因序列,自行设计筛选一对特异寡核苷酸引物,建立梅毒螺旋体的PCR。同时对其进行实验室评价和临床标本的检测验证。结果:PCR对梅毒螺旋体能产生特异性扩增,片段大小为252bp,而对其他生殖道常见菌及人基因组DNA不能扩增出任何片段。检测65例临床标本,PCR检查阳性54例(83.1%),梅毒螺旋体明胶颗粒凝集试验(TPPA)检查阳性52例(80%),梅毒螺旋体暗视野显微镜检查阳性40例(61.5%)。PCR检测结果,与暗视野显微镜检查结果比较,差异有显著性(P<0.01);与梅毒血清学检查结果比较,差异无显著性(P>0.05)。结论:PCR可特异、快速地检测梅毒螺旋体,并具有较好的敏感性。     

Immunity in syphilis. Studies in active immunity.

Support for the concept of the development of immunity during the course of syphilis is avaiable in the literature. In experimental syphilis in rabbits, some immunity is present approximately 3 weeks after infection with Treponema pallidum. Resistance to re-infection increases to a maximum at approximately 3 months after infection. Termination of this state by penicillin treatment within this 3-month period may enable re-infection to be accomplished. Attempts to reproduce this state of immunity experimentally by injection of T. pallidum itself, or protein derivatives, or ultrasonic disintegrates obtained from T. pallidum or non-pathogenic treponemes, have been unsuccessful. However, promising results in rabbits have resulted from injecting T. pallidum suspensions attenuated by storage at 4 degrees C, penicillin, or gamma irradiation, and also by suspensions preserved by glutaraldehyde. In the present study, partial resistance to intratesticular challenge in rabbits with T. pallidum has been obtained by immunization with a variety of non-pathogenic treponemes, as exemplified by the strains Nichols, Kazan 2, 4, 5, and 8, Treponema minutum, Treponema ambigua, Treponema refringens and Treponema microdentium. Success is attributed to the processing of immunizing antigens at 4 degrees C and storage until use at -20 degrees C. Attempts to attenuate T. pallidum by immunological means, namely, passage through a limited number of immunized rabbits, were unsuccessful.     

临床梅毒螺旋体菌株兔感染模型构建

目的：构建临床梅毒螺旋体菌株梅毒兔感染模型。方法：收集梅毒患者梅毒螺旋体菌株，制备菌悬液，将悬液注入新西兰兔睾丸并连续分离传代，观察新西兰雄兔临床症状及血清学变化情况。结果：共收集临床梅毒螺旋体菌6株 (A-F)，接种成功5株—A、C、D、E、F菌株，分别于接种后第28天、7天、14天、32天、35天检测到TPPA转阳。将获得的临床菌株A继续传代，接种6天开始睾丸出现肿胀，平均7.7天TPPA转阳。结论：通过兔睾丸接种的方法，可以成功分离传代临床梅毒螺旋体菌株。     

荧光定量PCR检测梅毒孕妇引产胎盘脐带组织中的梅毒螺旋体

目的：研究荧光定量PCR(FQ-PCR)检测梅毒孕妇引产胎盘脐带组织中的梅毒螺旋体，评估其在早期诊断先天梅毒中的作用。方法：采用荧光定量PCR技术检测13例梅毒孕妇引产胎盘脐带组织中的梅毒螺旋体DNA。结果：13例胎盘和脐带标本中6例(46．15％)荧光定量PCR检测阳性，6例阳性者中，4例未接受治疗，2例接受了治疗。结论：FQ-PCR可检出胎盘脐带组织中的梅毒螺旋体，可用于先天梅毒的早期诊断，干预治疗并不能完全阻断妊娠期间梅毒螺旋体的垂直传播。     

Immune responses to soluble antigens of treponemes.

Sonicates from five cultivable treponemes were used as antigens in delayed hypersensitivity tests and macrophage inhibition assays. Immunodiffusion analysis showed that the sonicate comprised two major antigenic components which were not distinguishable in the skin tests. The sonicate antigens elicited significant cell-mediated immunity in guinea-pigs. Treponema refringens biotype Nichols proved to induce the strongest delayed response. Delayed skin hypersensitivity to the antigens of Treponema pallidum was found in eight rabbits without orchitis, but not in six rabbits with T. pallidum orchitis. In contrast, the rabbits with syphilitic orchitis gave the strongest reactions with the non-pathogenic spirochetes. In terms of the cell-mediated immunity responses, Treponema phagedenis Reiter was found to be related to T. phagedenis Kazan 4 and Treponema denticola. Treponema scoliodontum was related to T. phagedenis Kazan 5, and T. refringens biotypes Nichols and refringens. The antigens of T. pallidum had the closest relationship to T. refringens biotypes refringens and Nichols ,T. phagedenis biotype Reiter, and T. scoliodontum. It was also demonstrated that some three of 12 human syphilitic sera reacted with the antigens of T. pallidum but not with control sera.     

Effects of oxygen and nitrogen on the character of T. pallidum is subcutaneous chambers in mice.

Nitrogen and oxygen gases were injected into mouse subcutaneous chambers which contained virulent Treponema pallidum. The effect of each gas on the viability and survival of T. pallidum in an in vivo system was determined. In comparison with the effects in nontreated control mice, injection of nitrogen enhanced both motility and survival time, but oxygen exerted a deleterious effect.     

Microcapsule agglutination test for Treponema pallidum antibodies. A new serodiagnostic test for syphilis.

For the serodiagnosis of syphilis a quantitative passive agglutination (MCA-TP) test for antibodies to Treponema pallidum was performed with chemically stable microcapsules with no antigenic activity instead of with conventional sheep erythrocytes. The microcapsules were easily sensitised with the antigen of sonicated Treponema pallidum by treatment with glutaraldehyde. Compared with the Treponema pallidum haemagglutination test (TPHA) the MCA-TP test was superior for detecting cases of primary syphilis. Furthermore, the decrease in antibody titre during treatment was more evident in this test than in the FTA-ABS or the TPHA tests. The MCA-TP test performed on IgM and IgG gel-filtered fractions of sera from patients with syphilis proved that the sensitised microcapsule antigen reacted sharply with the IgM antibodies specific to syphilis.     

Immune responses to soluble antigens of treponemes.

Sonicates from five cultivable treponemes were used as antigens in delayed hypersensitivity tests and macrophage inhibition assays. Immunodiffusion analysis showed that the sonicate comprised two major antigenic components which were not distinguishable in the skin tests. The sonicate antigens elicited significant cell-mediated immunity in guinea-pigs. Treponema refringens biotype Nichols proved to induce the strongest delayed response. Delayed skin hypersensitivity to the antigens of Treponema pallidum was found in eight rabbits without orchitis, but not in six rabbits with T. pallidum orchitis. In contrast, the rabbits with syphilitic orchitis gave the strongest reactions with the non-pathogenic spirochetes. In terms of the cell-mediated immunity responses, Treponema phagedenis Reiter was found to be related to T. phagedenis Kazan 4 and Treponema denticola. Treponema scoliodontum was related to T. phagedenis Kazan 5, and T. refringens biotypes Nichols and refringens. The antigens of T. pallidum had the closest relationship to T. refringens biotypes refringens and Nichols ,T. phagedenis biotype Reiter, and T. scoliodontum. It was also demonstrated that some three of 12 human syphilitic sera reacted with the antigens of T. pallidum but not with control sera.