IMMUNOCHEMISTRY OF GONOCOCCAL LIPOOLIGOSACCHARIDE

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。本项目继续研究低聚肌醇（LOS）模拟人鞘糖脂（GSL）如何使淋病奈瑟菌传播，以找到预防方法。LOW是外膜糖脂，具有由近端基底区和三个短的远端链（称为_，_和_）组成的糖部分。多链寡糖与乳糖（Lac-R）、球糖（P_（Gb3）和P1）、副球糖（乳糖-N-新四糖（LNnT））和神经节糖（GalNAc_1-LNnT）系列GSL的结构相同。LOS参与上皮细胞的附着和侵袭，以及免疫清除机制的逃避。淋病时淋球菌脱落使LOS增大。由MS1lmkC--一种用于人体实验的菌株--产生的更高的M_LOS具有聚乳糖胺结构。聚乳糖胺化解释了这种变体的较高M_分子，但不是其他变体的M_分子。一些血清抗性淋球菌菌株延伸LOS链形成与α链的α-乳糖平行的α-乳糖，脑膜炎球菌可以延伸α-乳糖链。 我们正在构建由临床分离株产生的更高M_LOS：由ser_菌株产生的LOS，以及似乎具有分别与副糖基和神经节糖基LOS同量异序的更高阶（Gb4和P-1）糖基寡糖的LOS。我们特别想知道是否更高的M_LOS具有平行的GSL样触角，可以交联上皮细胞受体。我们将继续依靠质谱技术，但也将利用高pH阴离子交换色谱分析。 我们对淋球菌LOS的类脂部分知之甚少。需要该信息是因为类脂部分以影响糖部分结合糖蛋白（包括抗体）的能力的方式影响糖部分的构象。从降解LOS获得的结构信息未探索已知的O-酰基类脂部分的异质性。我们将描述淋球菌类脂部分菌株之间的异质性，并进行更完整的类脂基团从选择菌株的结构分析。 单克隆抗体已被广泛用于淋球菌发病机制的研究作为替代物的葡萄糖结构。然而，我们还没有能够区分已知糖结构的单克隆抗体，更不用说那些尚未发现的结构了。我们计划扩大我们的单克隆抗体库，以包括更多的特异性。这些单克隆抗体将是必要的LOS在发病机制中的作用的完整的研究。

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. This project continues studies of how liooligosaccharide (LOS) mimicry of human glycosphingolipids (GSL) enables the transmission of Neisseria gonorrhoeae in order to find ways to prevent it. LOW are outer membrane glycolipids that have a glycose moiety that consists of proximal Basal Region and three short distal chains, termed _, _, and _. Many _ chain oligosaccharides are structurally identical to those of lacto- (Lac-R), globo- (P_(Gb3) and P1), paraglobo- (lacto-N-neotetraose (LNnT)), and gangliosyl (GalNAc_1-LNnT) series GSL. LOS are involved in attachment to and invasion of epithelial cells, and in evasion of immune clearance mechanisms. Gonococci shed during gonorrhoea make larger LOS. The higher M_ LOS made by MS1lmkC -- a strain used in human experimentation -- have polylactosamine structures. Polylactosaminylation explains the higher M_ molecules of this variant, but not those of others. Some serum resistant (ser_) gonococcal strains extend the LOS _ chain to form an _-lactose that is parallel to the _-lactose of the a chain, and meningococci can extend the _ chain. We are structuring higher M_ LOS made by clinical isolates: LOS made by ser_ strains, and LOS that appear to have higher order (Gb4 and P-1) globosyl oligosaccharides that are isobaric with paraglobosyl and gangliosyl LOS, respectively. We particularly want to know whether higher M_ LOS have parallel GSL-like antennae that could crosslink epithelial cell receptors. We will continue to rely on mass spectrometric techniques, but will also utilize high pH anion exchange chromatographic analyses. We know little about the lipoidal moieties of gonococcal LOS. This information is needed because the lipoidal moiety influences the conformation of the glycose moiety in ways that affect the latter's ability to bind glycoproteins, including antibodies. Available structural information from degraded LOS leaves unexplored the known O-acyl lipoidal moiety heterogeneity. We will profile gonococcal lipoidal moiety heterogeneity among strains, and perform more complete structural analysis on the lipoidal groups from select strains. Mabs have been used extensively in studies of gonococcal pathogenesis as surrogates for glycose structures. However, we do not have mAbs that discriminate among known glycose structures, much less for those that have yet to be found. We plan to expand our library of mAbs to include additional specificities. These mAbs will be necessary for complete studies of the role of LOS in pathogenesis.