PATHOGENESIS OF LYME NEUROBORRELIOSIS IN THE RHESUS MONKEY: STUDIES IN VITRO

这个子项目是许多研究子项目中的一个 由NIH/NCRR资助的中心赠款提供的资源。子项目及 研究者（PI）可能从另一个NIH来源获得了主要资金， 因此可以在其他CRISP条目中表示。所列机构为 研究中心，而研究中心不一定是研究者所在的机构。 已知伯氏疏螺旋体在多种细胞中诱导炎症介质的产生。我们假设在这种炎症环境中可能发生神经元凋亡，导致神经疏螺旋体病。在实验中，B.在体外与原代小胶质细胞共培养时，我们观察到IL-6和IL-8、CCL 2（MCP-1）、CCL 3（MIP-1）、CCL 4（MIP-1）和CCL 5（RANTES）的强烈释放，但我们没有检测到小胶质细胞凋亡的诱导。相反，SH-SY 5 Y（SY）神经母细胞瘤细胞与B共培养。Burgdorferi表达可忽略量的炎性介质，但也保持对细胞凋亡的抗性。SY细胞与小胶质细胞和B. burgdorferi，神经元凋亡持续发生。这些细胞培养物的共聚焦显微镜成像染色的细胞凋亡和细胞类型特异性标志物证实，这是主要的SY细胞死亡。微阵列分析进一步证明了强烈的小胶质细胞介导的炎症反应B。包括促炎细胞因子、Toll样受体2（TLR-2）和NF κ B基因转录物的上调。有趣的是，在炎症信号传导方面表现出最深刻变化的途径是髓样细胞上表达的触发受体-1（TREM 1）。在小胶质细胞和B存在下培养的神经元细胞中，也发生了重要的p53通路基因的转录改变。burgdorferi，这表明当与在B存在下培养的SY细胞相比时，从细胞存活到为凋亡做准备的转变。伯多菲力一个人。这些结果表明，B。burgdorferi对SY细胞没有直接毒性;相反，这些细胞通过旁观者效应在小胶质细胞产生的炎症环境中变得痛苦并死亡。这种神经元损伤可能最终导致神经疏螺旋体病中出现的神经认知症状。

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. Borrelia burgdorferi is known to induce the production of inflammatory mediators in a variety of cells. We hypothesized that in this inflammatory milieu neuronal apoptosis may occur, leading to neuroborreliosis. In experiments where B. burgdorferi was co-cultured in vitro with primary microglia, we observed robust release of IL-6 and IL-8, CCL2 (MCP-1), CCL3 (MIP-1¿), CCL4 (MIP-1¿) and CCL5 (RANTES), but we detected no induction of microglial apoptosis. In contrast, SH-SY5Y (SY) neuroblastoma cells co-cultured with B. burgdorferi expressed negligible amounts of inflammatory mediators but also remained resistant to apoptosis. When SY cells were co-cultured with microglia and B. burgdorferi, neuronal apoptosis consistently occurred. Confocal microscopy imaging of these cell cultures stained for apoptosis and with cell type-specific markers confirmed that it was predominantly the SY cells that were dying. Microarray analysis further demonstrated an intense microglia mediated inflammatory response to B. burgdorferi including up-regulation in gene transcripts for proinflammatory cytokines, Toll-like receptor 2 (TLR-2) and NF¿¿. Interestingly, the pathway that exhibited the most profound changes in regard to inflammatory signaling was triggering receptor expressed on myeloid cells-1 (TREM1). Significant transcript alterations in essential p53 pathway genes also occurred in neuronal cells cultured in the presence of microglia and B. burgdorferi, which indicated a shift from cell survival to preparation for apoptosis when compared to SY cells cultured in the presence of B. burgdorferi alone. These findings indicate that B. burgdorferi is not directly toxic to SY cells; rather, these cells become distressed and die in the inflammatory surroundings generated by microglia through a bystander effect. Such a neuronal impairment may eventually contribute to the neurocognitive symptoms seen in neuroborreliosis.