T cell-innate immune crosstalk regulates Staphylococcus aureus craniotomy infection

T细胞先天免疫串扰调节金黄色葡萄球菌开颅感染

• 批准号: 10590634
• 负责人: Tammy L Kielian
• 金额: $ 58.08万
• 依托单位: UNIVERSITY OF NEBRASKA MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-03-11 至 2027-02-28
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10590634
• 关键词: Address; Aneurysm; Animals; Anti-Bacterial Agents; Antibacterial Response; Antibiotics; Antibodies; Antigens; Attenuated; Bacteria; Binding; Brain; Burr hole procedure; CD4 Positive T Lymphocytes; CXCL10 gene; Cell Shape; Cells; Cellular Metabolic Process; Cephalic; Chronic; Clip; Containment; Craniotomy; Data; Development; Epilepsy; Excision; Exposure to; Future; Gene Expression Profile; Genes; Genetic Transcription; Goals; Growth; Human; Hydrocephalus; Immune; Immune response; Infection; Inflammatory; Interferon Type II; Invaded; Knockout Mice; Leucocytic infiltrate; Leukocytes; Macrophage; Magnetic Resonance Imaging; Mediating; Membrane; Microbial Biofilms; Microglia; Molecular; Morbidity - disease rate; Myeloid-derived suppressor cells; Neurologic Dysfunctions; Outcome; Pathway interactions; Patients; Pattern; Phagocytes; Phagocytosis; Play; Procedures; Process; Production; Property; Prophylactic treatment; Proteins; Rag1 Mouse; Regulation; Reporting; Residual state; Risk; Role; Sampling; Seizures; Shapes; Specificity; Staphylococcal Protein A; Staphylococcus aureus; Syndrome; T cell response; T-Cell Activation; T-Cell Depletion; T-Lymphocyte; Tissues; Virulence; Virulence Factors; antimicrobial; antimicrobial peptide; bactericide; bone; chronic infection; cranium plastic repair; effector T cell; experimental study; granulocyte; human disease; humanized mouse; improved; innovation; leukocyte activation; metabolic profile; monocyte; mouse model; mutant; neutrophil; novel; novel strategies; pathogen; prevent; recruit; response; single-cell RNA sequencing; subcutaneous; transcription factor; transcriptome; translational study; treatment strategy; tumor; virulence gene

A craniotomy is performed to access the brain for procedures that include tumor resection, localization and resection of epileptogenic foci, and aneurysm clipping, where the bone flap is replaced intraoperatively. Despite prophylaxis, infectious complications after craniotomy range from 1-3%, with approximately half caused by Staphylococcus aureus (S. aureus), which forms a biofilm on the bone flap that is recalcitrant to antibiotics. We have developed a mouse model of S. aureus craniotomy infection that shares important ultrastructural, MRI, and immune attributes with human disease, which can be exploited to identify mechanisms for infection persistence. Our preliminary results suggest that T cells maintain S. aureus in a biofilm state to minimize the shedding of planktonic bacteria into the brain. Ultimately, this helps protect the CNS parenchyma but does not clear the biofilm. This is supported by the fact that bacterial burden was unchecked in Rag1 KO mice and in WT animals following CD4+ T cell depletion, reflecting increased planktonic bacteria in the brain and galea. Furthermore, T cell loss coincided with an attenuated activation signature in microglia, macrophages, and granulocytes, with significant reductions in several IFN-ɣ-regulated genes, including CXCL10, indicative of T cell-innate immune crosstalk. We aim to understand this regulation in addition to T cell-biofilm crosstalk to devise novel strategies to promote biofilm eradication. This possibility is feasible given our innovative bacterial scRNA-seq data, where activated CD4+ T cells induced the expression of several S. aureus virulence genes, including protein A (spa) that binds the Fc portion of antibody to inhibit opsonophagocytosis. CXCL10 has been reported to induce Spa shedding from the bacterial membrane, which raises the intriguing possibility that CXCL10 induction by T cells promotes Spa release to block S. aureus phagocytosis, which is supported by our preliminary data where craniotomy infection was significantly reduced with a S. aureus spa mutant. This proposal will examine the hypothesis that CD4+ T cells regulate antimicrobial responses in the brain and galea by targeting microglia/macrophages vs. PMNs/G-MDSCs, respectively, to prevent bacterial outgrowth and limit invasion into the brain. In response, S. aureus alters its transcriptiome to augment virulence factor expression to promote biofilm persistence. This represents a host-pathogen triad that dictates infection outcome and the molecular mechanisms responsible for bacterial persistence in the brain and galea will be examined in the following Specific Aims: 1) Identify the critical CD4+ Th subset and antigen specificity in controlling S. aureus outgrowth during craniotomy infection; 2) Determine key mechanisms of T cell-innate immune crosstalk that dictate biofilm growth and CNS invasion; and 3) Identify S. aureus biofilm genes that are critical for subverting T cell effector function during craniotomy infection. An improved understanding of how T cells shape the innate immune landscape and S. aureus virulence during craniotomy infection may be leveraged to enhance antimicrobial activity and biofilm clearance to reduce patient morbidity.

开颅手术是为了进入大脑进行手术，包括肿瘤切除、定位和 致痫灶切除和动脉瘤夹闭，其中术中更换骨瓣。尽管 开颅术后感染性并发症的发生率为1- 3%，其中约一半是由以下因素引起的： 金黄色葡萄球菌(S.金黄色葡萄球菌），其在骨瓣上形成生物膜，该生物膜对抗生素是顽固的。我们 建立了S.金黄色葡萄球菌开颅术感染，具有重要的超微结构、MRI和 人类疾病的免疫属性，可用于识别感染持续性的机制。 我们的初步结果表明T细胞维持S.金黄色葡萄球菌，以最大限度地减少 浮游细菌进入大脑。最后，这有助于保护CNS实质，但不能清除 生物膜。这一点得到了以下事实的支持：在Rag 1 KO小鼠和WT动物中未检查到细菌负荷 CD 4 + T细胞耗竭后，反映脑和帽状物中浮游细菌增加。此外，T 细胞损失与小胶质细胞、巨噬细胞和粒细胞的激活信号减弱一致， 包括CXCL 10在内的几种IFN-γ调节基因显著减少，表明T细胞先天免疫 串话。我们的目标是了解这种调节除了T细胞生物膜串扰设计新的策略 以促进生物膜根除。鉴于我们创新的细菌scRNA-seq数据，这种可能性是可行的，其中 活化的CD 4 + T细胞可诱导多种S.金黄色葡萄球菌毒力基因，包括蛋白A（spa） 其结合抗体的Fc部分以抑制调理吞噬作用。据报道，CXCL 10可诱导Spa CXCL 10从细菌膜上脱落，这就提出了T细胞诱导CXCL 10的有趣的可能性。 促使SPA释放到S区。金黄色葡萄球菌吞噬作用，这得到了我们的初步数据的支持，其中 颅骨切开术感染明显减少。金黄色葡萄球菌spa突变体。本提案将审查 CD 4 + T细胞通过靶向调节脑和帽状体中的抗菌应答的假说 小胶质细胞/巨噬细胞与PMNs/G-MDSCs相比，分别防止细菌生长并限制侵入 大脑对此，S.金黄色葡萄球菌改变其转录组以增加毒力因子表达，从而促进 生物膜持久性。这代表了一个宿主-病原体三联体，它决定了感染的结果和分子水平。 负责细菌在脑和盔状花序中持久存在的机制将在下面进行检查 具体目的：1）确定控制S.金黄色葡萄球菌 开颅术感染期间; 2）确定T细胞-先天性免疫串扰决定生物膜的关键机制 生长和CNS侵袭;和3）鉴定S.金黄色葡萄球菌生物膜基因对破坏T细胞效应子至关重要 开颅术感染期间的功能。对T细胞如何塑造先天性免疫的进一步理解 Landscape和S.颅骨切开术感染期间的金黄色葡萄球菌毒力可用于增强抗菌 活性和生物膜清除以降低患者发病率。