Proteomics of Staphylococcus aureus nasal carriage

描述(由申请人提供)： 人鼻粘膜是一种可获得的、临床上重要的模型。 微生物与宿主防御系统相互作用的研究。鼻腔携带 金黄色葡萄球菌(SA)是临床上最常见的粘膜疾病 宿主防御，但其分子和细胞基础尚不清楚。这个 由于医院感染，精神障碍在临床上越来越重要 通常通过耐甲氧西林金黄色葡萄球菌和其他金黄色葡萄球菌的鼻腔携带传播 越来越多的菌株对抗生素产生抗药性。我们的证据表明 定植可能是由于鼻腔固有的抗菌活性受损。 流体。目前的提案旨在找出SA的根本原因(S) 通过检测SA承运人呼吸道定植的蛋白质决定因素进行载运 并将SA载体液体的杀微生物剂成分与来自 没有在南非定居的捐赠者。我们假设1)非承运商 表达抗微生物(多)肽因子，其中一些要么缺乏 或SA携带液中有缺陷，2)宿主防御因子改变或不足 呼吸道液体有助于金黄色葡萄球菌在携带者体内的逐渐定植， 3)纠正失调成分将恢复抗菌剂 金黄色葡萄球菌载体气道液对金黄色葡萄球菌的抗菌活性为了测试这些 假设，我们将：1)检测差异的阳离子(多)肽 携带SA的供者鼻液和供者鼻液之间的表达 利用一种新型的二维凝胶没有被SA定植的 电泳法(2-DE)，2)鉴定(多)肽 携带SA的捐赠者和未携带SA的捐赠者之间的差异表达 用SA定植，3)重建SA的抗菌活性 用不正常或缺失的(多)肽替代异常或缺失的多肽来携带鼻液 从非载体液体中提纯的完整的对应物。我们建议的研究 代表了一种识别和联系人类呼吸道疾病的新方法 生物标志物(阳离子多肽抗菌剂)及其作用(SA鼻腔 马车)。总而言之，这些研究将首次描述 寄主抗性因子是一种常见且日益重要的来源 医院感染，并会发展成一种被忽视但非常有用的自然 研究细菌与可接近粘膜相互作用的模型 浮出水面。

DESCRIPTION (provided by applicant): The human nasal mucosa is an accessible and clinically important model for the study of microbial interactions with host defenses. Nasal carriage of Staphylococcus aureus (SA) is the most common clinical disorder of mucosal host defense but its molecular and cellular basis is not understood. The disorder is of increasing clinical importance because nosocomial infections are commonly spread by nasal carriers of methicillin-resistant SA and other SA strains increasingly resistant to antibiotics. Our evidence indicates that colonization may be due to impaired innate antimicrobial activity of nasal fluid. The current proposal aims to identify the underlying cause(s) of SA carriage by examining protein determinants of SA carrier airways colonization and comparing microbicidal components of SA carrier fluid to nasal fluids from donors that are not colonized with SA. We hypothesize that 1) noncarriers express antimicrobial (poly)peptide factors some of which are either lacking or defective in SA carrier fluid, 2) altered or deficient host defense factors in airways fluid contribute to the progressive colonization of SA in carriers, and 3) correcting the dysregulated components will restore the antimicrobial activity of SA carrier airway fluid against isolates of SA. To test these hypotheses, we will: 1) detect cationic (poly)peptides that are differentially expressed between nasal fluid from donors carrying SA and fluid from donors that are not colonized with SA utilizing a novel two-dimensional gel electrophoresis (2-DE) approach, 2) identify (poly)peptides that are differentially expressed between donors carrying SA and donors that are not colonized with SA, and 3) reconstitute the antimicrobial activity of SA carrier nasal fluid by replacing abnormal or missing (poly)peptides with intact counterparts purified from noncarrier fluid. Our proposed studies represent a novel approach to identify and link human airway disease biomarkers (cationic polypeptide antimicrobials) with their effects (SA nasal carriage). Together, these studies will for the first time characterize the host resistance factors for a common and increasingly important source of nosocomial infection, and will develop a neglected but very useful natural model for the study of the interactions of bacteria with an accessible mucosal surface.