Interactions between Pseudomonas aeruginosa and Streptococcus salivarius and effects on the host immune response

铜绿假单胞菌和唾液链球菌之间的相互作用及其对宿主免疫反应的影响

基本信息

批准号：
10388005
负责人：
Sara N Stoner
金额：
$ 3.8万
依托单位：
UNIVERSITY OF ALABAMA AT BIRMINGHAM
依托单位国家：
美国
项目类别：
财政年份：
2022
资助国家：
美国
起止时间：
2022-02-01 至 2024-01-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10388005
关键词：
Adult Affinity Alginates Anti-Inflammatory Agents Bacteria Bacterial Infections Binding Binding Proteins Biological Assay Calorimetry Carbon Caucasians Cells Chronic Coculture Techniques Colony-forming units Communities Confocal Microscopy Cystic Fibrosis Cystic Fibrosis Transmembrane Conductance Regulator Data Deterioration Development Disease Outcome Drosophila melanogaster Enzyme-Linked Immunosorbent Assay Epithelial Cells Genetic Diseases Growth Histopathology Hour Human IL8 gene Immune Immune Evasion Immune response In Vitro Infection Infiltration Inflammation Inflammatory Inflammatory Response Interleukin-1 Interleukin-1 alpha Interleukin-1 beta Interleukin-6 Kinetics Laser Microscopy Learning Lectin Literature Lung Lung infections Measures Mediating Metabolism Microbial Biofilms Modeling Mucociliary Clearance Mucous body substance Multi-Drug Resistance Mutation NF-kappa B Neutrophil Infiltration Pathogenesis Pathway interactions Persons Play Production Pseudomonas aeruginosa Pseudomonas aeruginosa infection Pulmonary Cystic Fibrosis Pulmonary Inflammation Rattus Regulator Genes Research Role SECTM1 gene Source Stains Streptococcus Streptococcus salivarius TNF gene Techniques Testing Thick Tissues Titrations Virulence Work antimicrobial base bronchial epithelium chronic infection co-infection commensal bacteria cystic fibrosis patients cytokine drug resistant pathogen experience histological stains improved in vivo lung colonization lung injury lung microbiota male maltose-binding protein microbial mortality multi-drug resistant pathogen novel oral commensal oral streptococci overexpression pathogen pulmonary function recruit respiratory respiratory colonization respiratory pathogen response

项目摘要

PROJECT SUMMARY Pseudomonas aeruginosa is a multi-drug resistant pathogen which causes chronic lung infections and is a leading cause of mortality in cystic fibrosis (CF) patients. P. aeruginosa produces a biofilm matrix which protects the bacterium from antimicrobials and aids in host immune evasion. The main component of this biofilm matrix are three exopolysaccharides- Pel, Psl, and alginate. Additionally, P. aeruginosa contributes to inflammation and lung damage by activating the pro-inflammatory NF-κB pathway in host cells, leading to the production of inflammatory cytokines and recruitment of inflammatory immune cells to the lungs, causing subsequent tissue damage. NF-κB activation is naturally elevated in the lungs of CF patients, which is further exacerbated by P. aeruginosa infection. Although P. aeruginosa is generally studied as an isolated infection, other species colonize the lungs of CF patients and could potentially modulate P. aeruginosa virulence. Colonization of oral streptococci in the lungs has recently been associated with CF lung stability. Of these oral streptococci, Streptococcus salivarius, was found to be the most prevalent streptococcal species in the lungs of CF patients. S. salivarius has been shown to inhibit growth of multiple respiratory pathogens, as well as inhibit activation of the NF-κB pathway in human bronchial epithelial cells. Although S. salivarius has been correlated with stable lung function in CF patients, no studies have examined interactions between S. salivarius and P. aeruginosa and their impact on the host response. To characterize the interactions between the two species, we first measured changes in biofilm formation of the two species when co-cultured. Our preliminary results demonstrated that S. salivarius biofilm formation is significantly increased in the presence of the exopolysaccharide Psl, which is produced by the non-mucoid P. aeruginosa strain PAO1. Additionally, the S. salivarius maltose-binding protein MalE was overexpressed in the presence of P. aeruginosa. Aim 1 will test the hypothesis that MalE interacts with Psl to promote biofilm formation of S. salivarius. Whole-cell ELISA and isothermal titration calorimetry will be used to characterize the binding affinity of the two targets. Our preliminary data also demonstrated that Drosophila melanogaster were protected from P. aeruginosa-mediated killing in the presence of S. salivarius, highlighting the need to further examine the impact of S. salivarius on P. aeruginosa pathogenesis. Aim 2 will test the hypothesis that the presence of S. salivarius in the CF lung improves lung function by downregulating pro- inflammatory cytokines downstream of NF-κB produced in response to P. aeruginosa infection. We will develop a CF rat model of co-infection in which we measure specific pro-inflammatory cytokines, neutrophil recruitment, and lung histopathology during P. aeruginosa infection in the presence or absence of S. salivarius. Data generated from this proposal will promote our understanding of how S. salivarius incorporates into the P. aeruginosa biofilm and modulates the host response to a P. aeruginosa infection.

项目概要铜绿假单胞菌是一种具有多重耐药性的病原体，可引起慢性肺部感染，是一种铜绿假单胞菌产生保护性生物膜基质，是导致囊性纤维化 (CF) 患者死亡的主要原因。抗菌剂中的细菌并有助于宿主免疫逃避该生物膜基质的主要成分。是三种胞外多糖——Pel、Psl 和藻酸盐，此外，铜绿假单胞菌还会导致炎症和炎症。通过激活宿主细胞中的促炎性 NF-κB 通路，导致产生肺损伤炎症细胞因子和炎症免疫细胞募集到肺部，导致随后的组织 CF 患者肺部的 NF-κB 激活自然升高，而 P. 铜绿假单胞菌感染虽然通常将铜绿假单胞菌作为一种孤立的感染进行研究，但其他物种也会定殖。 CF 患者的肺部，并可能调节口腔链球菌的铜绿假单胞菌毒力。最近，在这些口腔链球菌中，链球菌与 CF 肺稳定性相关。唾液链球菌被发现是 CF 患者肺部最常见的链球菌。已被证明可以抑制多种呼吸道病原体的生长，并抑制 NF-κB 的激活尽管唾液链球菌与稳定的肺功能相关。在 CF 患者中，没有研究检验唾液链球菌和铜绿假单胞菌之间的相互作用及其影响为了表征两个物种之间的相互作用，我们首先测量了我们的初步结果表明，两种物种共培养时生物膜的形成。存在胞外多糖 Psl 时，生物膜形成显着增加，胞外多糖 Psl 是由非粘液铜绿假单胞菌菌株 PAO1 此外，唾液链球菌麦芽糖结合蛋白 MalE 是在铜绿假单胞菌存在下过表达目标 1 将检验 MalE 与 Psl 相互作用的假设。促进唾液链球菌生物膜形成全细胞 ELISA 和等温滴定量热法将用于我们的初步数据还证明了果蝇的结合亲和力。在唾液链球菌存在的情况下，黑腹果蝇免受铜绿假单胞菌介导的杀死，强调需要进一步研究唾液链球菌对铜绿假单胞菌发病机制的影响，目标 2 将测试。假设 CF 肺中存在唾液链球菌，通过下调亲我们将开发响应铜绿假单胞菌感染而产生的 NF-κB 下游的炎症细胞因子。 CF大鼠混合感染模型，我们测量特定的促炎细胞因子、中性粒细胞募集、以及在存在或不存在唾液链球菌的情况下铜绿假单胞菌感染期间的肺组织病理学。该提案产生的结果将促进我们对 S. salivarius 如何融入 P. 铜绿假单胞菌生物膜并调节宿主对铜绿假单胞菌感染的反应。