巨细胞病毒gB基因分型介导的细胞感染嗜性与炎症相关性青光眼的关系及其机制

The relationship between human cytomegalovirus (HCMV) and glaucoma associated with inflammation, especially glaucomatocyclitic crisis, has drawn more and more attention. However, the mechanisms still remain unclear. Our previous study has found that HCMV genotype was gB3 for the viral strain isolated from the aqueous humor of glaucomatocyclitic crisis patients. However, the HCMV genotype was gB1 in corneal endotheliitis patients. The results indicate that HCMV gB genotype may play a key role in the pathogenesis of these diseases. So far, there is no report on the relationship between HCMV gB genotype and glaucoma associated with inflammation. Based on our previous study and published literatures, we hypothesize that: viral tropism to cells in the anterior chamber is determined by HCMV gB genotypes, which results in different clinical manifestations in corneal endotheliitis and glaucomatocyclitic crisis. The purpose of this study is to explore the role and mechanism of HCMV gB genotype in the pathogenesis of glaucoma associated with inflammation. HCMV strains are isolated from aqueous humor of glaucomatocyclitic crisis and corneal endotheliitis patients and amplified in vitro. Animal model is established by anterior chamber injection. Pathological changes and inflammatory reactions in the anterior section are evaluated to explore the viral tropism of different HCMV genotypes and its relationship with corneal endotheliitis and glaucomatocyclitic crisis. The results of this study will further clarify the etiology and pathogenesis of glaucoma associated with inflammation and provide a new experimental basis for the diagnosis and treatment of these diseases.

人巨细胞病毒（HCMV）与炎症相关性青光眼尤其是青睫综合征的关系越来越引起关注，但其致病机制尚不清楚。我们前期研究发现，青睫综合征患者房水中分离出的HCMV为gB3基因型，而巨细胞病毒性角膜内皮炎为gB1型，提示HCMVgB基因分型在上述疾病的发生中起关键作用。目前未见HCMVgB基因分型与炎症相关性青光眼关系的研究报道。依据前期研究及文献分析，我们提出假说：引起青睫综合征和角膜内皮炎的HCMV具有不同gB基因型，由于gB基因介导的前房细胞感染嗜性不同，导致产生不同的疾病。本研究拟从gB基因型这一新角度出发，将临床分离HCMV体外扩增后建立动物模型，分析不同基因型HCMV对前房内组织细胞的感染嗜性，并观察炎症反应特点及细胞病理改变，探讨HCMVgB基因分型与青睫综合征及角膜内皮炎的关系。研究结果将进一步明确炎症相关性青光眼的病因及发病机制，为临床上这类疾病的诊断和治疗提供新的实验依据。

炎症相关性青光眼约占所有青光眼临床病例的三分之一，是一类易反复发作的难治性青光眼。近年来巨细胞病毒（HCMV）与炎症相关性青光眼特别是青睫综合征的关系越来越引起关注，但其致病机制目前尚不明确。本项目收集不同类型炎症相关性青光眼的临床病例，观察和分析其临床特征，抽取患者房水样本，应用QAH-INF-G3蛋白质芯片进行炎症因子检测，实时荧光定量PCR检测房水中HCMV病毒DNA的含量，分析抗病毒治疗对这些患者的疗效以及与房水中病毒DNA含量关系。研究结果证实了房水中HCMV病毒DNA阳性的患者，对2%更昔洛韦滴眼液或口服更昔洛韦胶囊反应敏感，表明这类炎症相关性青光眼的病因与HCMV前房感染密切相关，且抗病毒治疗疗效确切。为进一步分析HCMV前房感染后致病的分子机制，在体外将HCMV接种到MRC-5细胞，病毒扩增后注射到大鼠前房，在成功建立HCMV前房感染大鼠模型的基础上，观察前房炎症反应特点及细胞病理学改变。研究结果发现HCMV最高浓度2×105PFU组在注射2周后，瞳孔区出现炎症性渗出，角膜后KP，以及瞳孔缘的Koeppe结节，组织学分析可见小梁网水肿，小梁网细胞肿胀，以及细胞内病毒颗粒的复制，提示与HCMV感染后眼压升高有关。本项目证实了HCMV前房感染与炎症相关性青光眼密切相关，病毒在小梁网的复制是导致眼压升高的主要原因，研究结果为进一步阐明炎症相关性青光眼的发病机制，以及临床上这类疾病的诊断和治疗提供了新的实验依据。