Development of nonhuman primate model of S. aureus nasal carriage

 描述(申请人提供)：金黄色葡萄球菌(SA)鼻腔携带是一种常见的疾病，容易导致严重的社区获得性和医院感染，并作为传播病原菌的重要宿主。我们开始认识到宿主和细菌决定因素共同作用于载体状态，并利用鼻腔上皮细胞和上呼吸道体外组织模型来更好地确定细菌和宿主决定因素在SA鼻腔携带中的作用。然而，为了证实这些因素在鼻腔携带中的体内作用，一个合适的动物模型。 将需要南澳殖民地化。虽然有用，但小鼠模型并不是研究长期SA鼻腔携带或宿主对定植反应的理想方法，因为这些动物不是自然定植的SA，过高的接种量只会导致短暂的定植，并且小鼠的鼻子不能很好地模拟人类鼻子的粘膜宿主反应。因此，目前的型号无法承受在其自然状态下测试SA运载的能力。非人灵长类动物可能更适合用来模拟人类的鼻腔运输。我们探索了辫尾猕猴是否可以作为实验性SA鼻腔定植的生物学相关模型，并发现超过一半的动物是SA鼻腔定植。遗传分析显示，人类和猕猴的鼻腔SA之间存在序列同源性，这表明辫子猕猴的鼻子可以实验地被人类来源的SA菌株定植。本研究旨在建立一种简便、经济的辫尾猕猴鼻腔携带金黄色葡萄球菌的模型，并利用该模型评估宿主对金黄色葡萄球菌定植的黏膜反应。在目标1中，我们将利用每只猕猴自己的SA鼻腔分离株建立尾辫猕猴鼻腔携带模型，然后使用该模型来探索临床上相关的鼻部人类SA菌株如何定植猕猴鼻腔。在用猕猴和临床相关的鼻部人类SA菌株进行实验性鼻腔定植后，将通过量化细菌载量和对回收的SA进行基因分型来评估携带水平两个月，以确认接种的菌株是否继续定植。在目标2中，我们将利用尾辫猕猴模型来确定鼻腔携带SA如何影响体内固有的粘膜宿主防御。鉴于我们已经报道过携带金黄色葡萄球菌的人的鼻液在体外杀死金黄色葡萄球菌的能力不足，我们将确定携带金黄色葡萄球菌的猕猴的鼻液在体外杀灭金黄色葡萄球菌前后是否同样缺乏鼻液。 体内实验性金黄色葡萄球菌定植。我们还将利用一种稳健的蛋白质组学方法来评估实验性SA定植对抗菌多肽、炎症标志物和其他粘膜宿主防御成分表达的生物学影响。总而言之，我们将为该领域提供一个非人类灵长类动物模型，用于研究SA鼻腔携带的决定因素，并测试候选抗SA鼻腔预防措施的安全性和有效性。

 DESCRIPTION (provided by applicant): Staphylococcus aureus (SA) nasal carriage is a common condition that predisposes individuals to severe community-acquired and nosocomial infections, and acts as an important reservoir for spreading pathogenic strains. We are beginning to understand that host and bacterial determinants collectively contribute to the carrier state, and have utilized nasal epithelial cells and ex vivo tissue models of the upper airways to better define the role of bacterial and host determinants of SA nasal carriage. However, to confirm the in vivo role of these factors in nasal carriage, a suitable animal model of SA colonization would be required. While useful, murine models are not ideal for studying longterm SA nasal carriage or the host's response to colonization, since these animals are not naturally colonized by SA, extraordinarily high inocula result only in transient colonization, and murine noses poorly model the mucosal host response of human noses. Thus, current models do not afford the ability to test SA carriage in its natural state. Nonhuman primates would likely better serve to model human SA nasal carriage. We explored whether pigtailed macaques could be used as a biologically relevant model of experimental SA nasal colonization, and discovered that over half were nasally colonized by SA. Genetic analyses revealed sequence homology between nasal SA of humans and macaques, suggesting that pigtailed macaque noses could be experimentally colonized with human-derived SA strains. This proposal seeks to develop a tractable, cost-effective model of nasal carriage of SA in pigtailed macaques, and utilize the model to assess the host's mucosal response to SA colonization. In Aim 1, we will develop the pigtailed macaque nasal carriage model using each macaque's own SA nasal isolate, and then use the model to explore how clinically relevant nasal human SA strains colonize macaque noses. Following experimental nasal colonization with macaque and clinically relevant nasal human SA strains, level of carriage will be assessed for two months by quantifying bacterial load and genotyping the recovered SA to confirm whether colonization persists with the inoculated strains. In Aim 2, we will utilize the pigtailed macaque model to determine how nasal carriage of SA affects innate mucosal host defense in vivo. Given we have reported that nasal fluids from human carriers of SA are deficient in killing SA in vitro, we will determine whether nasal fluids from macaques that carry SA in their noses are similarly deficient before and after in vivo experimental SA colonization. We will also utilize a robust proteomic approach to evaluate the biological effect of experimental SA colonization on the expression of antimicrobial polypeptides, inflammatory markers, and other mucosal host defense components. Collectively, we would provide the field with a nonhuman primate model for studying determinants of SA nasal carriage, and testing the safety and efficacy of candidate anti-SA nasal prophylaxes.