Antigenic variation of Mycoplasma genitalium during persistent genital tract infection of pig-tailed macaques

猪尾猕猴生殖道持续感染过程中生殖支原体的抗原变异

基本信息

批准号：
10516741
负责人：
Gwendolyn Wood
金额：
$ 19.44万
依托单位：
UNIVERSITY OF WASHINGTON
依托单位国家：
美国
项目类别：
财政年份：
2021
资助国家：
美国
起止时间：
2021-11-01 至 2024-10-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10516741
关键词：
Adherence Alleles Animal Model Animals Antibiotic Resistance Antibodies Antigenic Variation Antigens Antimicrobial Resistance Appearance Autopsy Awareness Bacteria Bacterial Adhesins Cells Cervical Cervicitis Cervix Uteri Chlamydia trachomatis Clinic Clinical Development Diagnostic Diagnostic tests Disease Effector Cell Enzyme-Linked Immunosorbent Assay Exudate FDA approved Female Genes Goals Histology Immune Immune Evasion Immune response Immunity Immunologic Monitoring In Situ In Vitro Individual Infection Infertility Infiltration Inflammation Inflammatory Invaded Macaca nemestrina Mammalian Oviducts Modeling Molecular Moxifloxacin Mycoplasma genitalium National Institute of Allergy and Infectious Disease Natural History Nature Neisseria gonorrhoeae Pathogenesis Pathology Patients Pelvic Inflammatory Disease Phase Population Study Premature Birth Prevalence Primates Process Production Protein Fragment Proteins Public Health Recombinants Recommendation Research Resistance Role Sequence Analysis Serology test Serum Sexual Transmission Sexually Transmitted Diseases Specimen Spontaneous abortion Time Tissues Treatment Efficacy Urethritis Variant Western Blotting Woman Work animal model development azithromycin resistance biological specimen archives chemokine cytokine detection assay experimental study genome sequencing high risk high risk population immune cell infiltrate improved men multiplex detection pathogen pathogenic bacteria prevent reproductive tract resistant strain whole genome

项目摘要

PROJECT SUMMARY Mycoplasma genitalium (MG), a sexually transmitted bacterial pathogen, is increasingly recognized as a significant public health concern. The prevalence of MG ranges from 1-4% in population-based studies to more than 20% in patients at high risk of acquiring sexually transmitted infections. The disease spectrum of MG is similar to Neisseria gonorrhoeae and Chlamydia trachomatis, and includes urethritis in men and cervicitis in women. Of particular concern, MG infection is associated with serious upper reproductive tract sequelae in women including pelvic inflammatory disease, infertility, preterm birth, and spontaneous abortion. Alarmingly, antimicrobial resistance in MG is increasing: 40-100% of strains are completely resistant to azithromycin and some infections are totally untreatable with US approved therapies. The recent FDA approval of two MG diagnostic tests will certainly increase public awareness of MG and demands for improved treatment. An animal model is urgently needed to understand the naturally history of MG infection including mechanisms of persistence and immune evasion, studies that are difficult in patients given the imperative to treat symptomatic infection. We have optimized our pig-tailed macaque model of persistent genital tract infection and now propose to use this model to study the role of antigenic variation in immune avoidance. Extending our previous work defining mechanisms of antigenic and phase variation of the immunodominant MgpB and MgpC adhesin proteins, we will determine if variation is required for persistence in the genital tract. First, using whole genome sequencing we will correlate the appearance of variants during 18 weeks of infection with the appearance of antibodies specific to MgpB and MgpC in three MG-infected primates and archived specimens from prior primate experiments. Second, the ability of the identical vs variant strain to re-infect animals that clear genital tract infection will be assessed in order to understand strain specific immunity. Third, a non-variable, “locked” MG strain that is unable to undergo antigenic variation will be constructed and characterized in vitro. Three primates will be inoculated cervically with a mixed inoculum of wild type and “locked” MG to compare the persistence and upper tract ascension of the two strains simultaneously over the 18 weeks of our model. All infected primates will undergo necropsy to examine the cervix, uterus, and Fallopian tubes for gross pathology and histology, and to assess the presence of MG in the upper reproductive tract. These experiments will not only determine if gene variation is required for persistence but will also provide additional observations in individual primates of the natural history of lower tract persistence, upper tract ascension, and immune response (including cytokines, cellular infiltrates and antibodies specific for conserved and variable MG antigens). These proposed experiments are highly significant in that they fill research gaps prioritized by NIAID-sponsored panels, namely the development of an animal model, the exploration of the role of MG in serious upper reproductive tract disease in women, and the development of an MG serologic test.

项目概要生殖支原体 (MG) 是一种性传播细菌病原体，越来越多地被认为是一种性传播细菌病原体。在基于人群的研究中，MG 的患病率范围为 1-4%。患有性传播感染的高风险患者的患病率超过 20%。 MG 的疾病谱为：与淋病奈瑟菌和沙眼衣原体相似，包括男性尿道炎和女性宫颈炎尤其值得关注的是，MG 感染与严重的上生殖道后遗症有关。女性，包括盆腔炎、不孕症、早产和自然流产。 MG 的抗菌药物耐药性正在增加：40-100% 的菌株对阿奇霉素完全耐药，并且有些感染是美国批准的疗法完全无法治疗的，FDA 最近批准了两种 MG。诊断测试肯定会提高公众对重症肌无力的认识以及改善治疗的需求。迫切需要动物模型来了解 MG 感染的自然史，包括机制持久性和免疫逃避，由于必须对症治疗，因此在患者中进行研究很困难我们已经优化了持续性生殖道感染的猪尾猕猴模型。提议使用该模型来研究抗原变异在免疫回避中的作用。确定免疫显性 MgpB 和 MgpC 粘附素的抗原和相变机制的工作蛋白质，我们将首先使用全基因组来确定变异是否需要在生殖道中持续存在。测序后，我们将感染 18 周期间变异的出现与三只感染 MG 的灵长类动物和之前存档的标本中的 MgpB 和 MgpC 特异性抗体其次，相同菌株与变异菌株重新感染清除生殖器的动物的能力。将评估呼吸道感染，以了解菌株特异性免疫。第三，非可变的“锁定”免疫。无法进行抗原变异的 MG 菌株将在体外构建和表征。将用野生型和“锁定”MG 的混合接种物对灵长类动物进行宫颈接种，以比较在我们的模型的 18 周内，两种菌株同时持续存在并上升。受感染的灵长类动物将接受尸检，检查子宫颈、子宫和输卵管的大体病理学和组织学，并评估上生殖道中 MG 的存在。这些实验不会。仅确定基因变异是否是持久性所必需的，但还将提供额外的观察结果个体灵长类动物的下束持续、上束提升和免疫的自然史反应（包括细胞因子、细胞浸润和保守型和可变型 MG 特异性抗体）这些拟议的实验非常重要，因为它们填补了优先考虑的研究空白。 NIAID 赞助的小组，即动物模型的开发、MG 在女性严重的上生殖道疾病，以及 MG 血清学检测的发展。