STRUCTURAL ANALYSIS OF GLYCOLIPID ANTIGENS OF LEISHMANIA PIFANOI AMASTIGOTES

皮法诺利什曼原虫无鞭毛体糖脂抗原的结构分析

• 批准号: 7369217
• 负责人: Diane McMahon Pratt
• 金额: $ 0.19万
• 依托单位: BOSTON UNIVERSITY MEDICAL CAMPUS
• 依托单位国家: 美国
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-07-01 至 2007-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7369217
• 关键词: STRUCTURAL; ANALYSIS; GLYCOLIPID; ANTIGENS; LEISHMANIA

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Protozoan parasites of the genus Leishmania cause a number of diseases in humans. The parasite undergoes a complex life cycle, alternating between an insect vector (promastigotes) and their mammalian hosts (amastigotes). In a mouse model, vaccination with proteoglycolipid complex (P-8) of Leishmania pifanoi amastigotes provides partial to complete protection against infection by this organism. Therefore the P-8 complex represents a potential vaccine candidate for leishmaniasis and structural characterization of the glycolipid antigens of Leishmania pifanoi amastigotes is a necessary step in the vaccine development. Monoclonal antibodies to the P-8 complex recognize four related glycolipid components, but detailed structures of the glycolipids in the active fractions remain to be determined. Based on the preliminary results, the glycolipids are expected to belong to one of the classes of either glycoinositol-phospholipids or lipophosphoglycan precursors. Monosaccharide composition analysis confirms the presence of carbohydrate components in each fraction. MALDI FTMS offers a number of advantages for structural analysis of glycolipids such as direct ionization of samples retained on the surface of TLC plates and capability for multistage dissociation of MALDI-generated ions. Previous MALDI FTMS and MS/MS spectra obtained for the P8 samples as unseparated mixtures, as partly purified components and as spots separated on TLC, are consistent with the presence of glycolipids with carbohydrate moieties of varying lengths. So far, all the structures match types previously reported. ESI-MS has led to the identification of a few simple lipids, and MALDI-TOF MS has yielded previously-characterized m/z values, but not novel ones. Further purification combined with new improvements of our TLC MALDI FTMS capabilities, and a newly set up system for lipid LCMS should help in the acquisition of full structural information that will enable identification of minor components in the active fractions.

该子项目是利用NIH/NCRR资助的中心赠款提供的资源的许多研究子项目之一。子项目和研究者（PI）可能从另一个NIH来源获得主要资金，因此可以在其他CRISP条目中表示。所列机构为中心，不一定是研究者所在机构。利什曼原虫属的原生动物寄生虫在人类中引起许多疾病。寄生虫经历复杂的生命周期，在昆虫载体（前鞭毛体）和哺乳动物宿主（无鞭毛体）之间交替。在小鼠模型中，用利什曼原虫无鞭毛体的蛋白糖脂复合物（P-8）接种疫苗提供了部分至完全的针对该生物体感染的保护。因此，P-8复合物代表了一种潜在的利什曼病疫苗候选物，并且对利什曼原虫无鞭毛体糖脂抗原的结构表征是疫苗开发中的必要步骤。单克隆抗体的P-8复合物识别四个相关的糖脂成分，但活性馏分中的糖脂的详细结构仍有待确定。根据初步结果，糖脂预计属于肌醇磷脂或脂磷酸聚糖前体的类别之一。单糖组成分析证实了每个馏分中存在碳水化合物组分。MALDI FTMS为糖脂的结构分析提供了许多优势，例如保留在TLC板表面上的样品的直接电离和MALDI产生的离子的多级解离的能力。P8样品作为未分离混合物、部分纯化组分和TLC上分离的斑点获得的先前MALDI FTMS和MS/MS光谱与存在具有不同长度碳水化合物部分的糖脂一致。到目前为止，所有的结构都符合以前报道的类型。ESI-MS已经鉴定了一些简单的脂质，MALDI-TOF MS已经产生了先前表征的m/z值，但不是新的。进一步纯化结合我们的TLC MALDI FTMS能力的新改进，以及新建立的脂质LCMS系统，应有助于获得完整的结构信息，这将使活性馏分中的次要组分的鉴定。