T-Cell response to CD1-restricted lipids in Tuberculosis

结核病中 T 细胞对 CD1 限制性脂质的反应

• 批准号: 6965263
• 负责人: DAVID Branch MOODY
• 金额: $ 43.75万
• 依托单位: BRIGHAM AND WOMEN'S HOSPITAL
• 依托单位国家: 美国
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-03-01 至 2011-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6965263
• 关键词: CD1 molecule; Mycobacterium tuberculosis; SCID mouse; T lymphocyte; antibody specificity; antigen antibody reaction; antigen presentation; cellular immunity; enzyme linked immunosorbent assay; flow cytometry; glycolipids; host organism interaction; human tissue; immunologic memory; immunoregulation; leukocyte activation /transformation; mass spectrometry

DESCRIPTION (provided by applicant): M. tuberculosis has infected 1.8 billion humans and accounts for 2 to 3 million deaths annually based on its ability to persist as an intracellular pathogen in human tissues. The host response to mycobacterial infection depends crucially on T cells, which until recently, were thought to be activated solely by peptide antigens bound to MHC class I and II proteins. The discovery of CD1 antigen presenting molecules shows how Langerhans cells and dendritic cells can activate T cells by presenting lipid antigens, including glucose monomycolate (Science 278, p. 283), mannosyl phosphomycoketides (Nature 404, p.884) and mycobactin like lipopeptides (Science 303, p. 527). This proposal aims to use high performance liquid chromatography to isolate immunodominant antigens from the M. tuberculosis and M. leprae cell walls and then determine their structures using collision induced dissociation mass spectrometry, nuclear magnetic resonance and Xray crystallography. Because mycobacteria remodel their cell walls and alter their antigen profiles during adaptation to intracellular growth, antigen discovery efforts will focus on pathogenic mycobacteria isolated directly from mammalian tissues and genetically modified M. tuberculosis that are deficient in the enzymes necessary for iron-scavenging from host tissues. The immunogenicity of each lipid antigen will be investigated by ex vivo analysis of T cell precursor frequencies in tuberculosis patients as measured by cytokine-capture ELISA, cell surface cytokine-capture immunofluorescence and staining with lipid-loaded CD1 tetramers. By measuring memory responses and the complexity of lipid antigen specificities in the CD 1-restricted T cell repertoire, these studies will provide insight into the basic question of whether CD1 functions in the innate or acquired immune responses in humans. In addition, identification of the precise molecular structures of antigenic lipids offers the prospect of fundamentally novel, MHC-unrestricted immunodulatory drugs and vaccines against leprosy, tuberculosis and multi-drug resistant tuberculosis.

描述（由申请人提供）：M。结核病已经感染了18亿人，并且基于其在人体组织中作为细胞内病原体持续存在的能力，每年造成200万至300万人死亡。宿主对分枝杆菌感染的反应关键取决于T细胞，直到最近，T细胞被认为仅由与MHC I类和II类蛋白结合的肽抗原激活。CD1抗原呈递分子的发现显示了朗格汉斯细胞和树突细胞如何通过呈递脂质抗原激活T细胞，所述脂质抗原包括葡萄糖单霉菌酸酯（Science 278，第283页）、甘露糖基磷酸霉菌酮（Nature 404，第884页）和分枝杆菌素样脂肽（Science 303，第527页）。本研究旨在利用高效液相色谱法从支原体中分离免疫显性抗原。结核和M.麻风细胞壁，然后使用碰撞诱导解离质谱，核磁共振和X射线晶体学确定它们的结构。由于分枝杆菌在适应细胞内生长的过程中重塑其细胞壁并改变其抗原谱，因此抗原发现工作将集中在直接从哺乳动物组织分离的致病性分枝杆菌和遗传修饰的分枝杆菌。结核病是缺乏从宿主组织中清除铁所必需的酶。将通过离体分析结核病患者中的T细胞前体频率来研究每种脂质抗原的免疫原性，所述T细胞前体频率通过组氨酸捕获ELISA、细胞表面组氨酸捕获免疫荧光和用脂质负载的CD 1四聚体染色来测量。通过测量记忆应答和CD 1限制性T细胞库中脂质抗原特异性的复杂性，这些研究将提供对CD 1在人类先天性或获得性免疫应答中是否起作用的基本问题的深入了解。此外，抗原脂质的精确分子结构的鉴定提供了针对麻风病、结核病和多药耐药结核病的基本新颖的、MHC不受限制的免疫调节药物和疫苗的前景。