Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, WA, USA.
Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, WA, USA.
Cell Rep. 2020 Mar 17;30(11):3663-3670.e5. doi: 10.1016/j.celrep.2020.02.081.
Arp is an immunogenic protein of the Lyme disease spirochete Borrelia burgdorferi and contributes to joint inflammation during infection. Despite Arp eliciting a strong humoral response, antibodies fail to clear the infection. Given previous evidence of immune avoidance mediated by the antigenically variable lipoprotein of B. burgdorferi, VlsE, we use passive immunization assays to examine whether VlsE protects the pathogen from anti-Arp antibodies. The results show that spirochetes are only able to successfully infect passively immunized mice when VlsE is expressed. Subsequent immunofluorescence assays reveal that VlsE prevents binding of Arp-specific antibodies, thereby providing an explanation for the failure of Arp antisera to clear the infection. The results also show that the shielding effect of VlsE is not universal for all B. burgdorferi cell-surface antigens. The findings reported here represent a direct demonstration of VlsE-mediated protection of a specific B. burgdorferi surface antigen through a possible epitope-shielding mechanism.
Arp 是莱姆病螺旋体伯氏疏螺旋体的一种免疫原性蛋白，它有助于感染期间的关节炎症。尽管 Arp 引起了强烈的体液免疫反应，但抗体未能清除感染。鉴于先前有证据表明伯氏疏螺旋体抗原可变的脂蛋白 VlsE 介导了免疫逃避，我们使用被动免疫测定来检查 VlsE 是否能保护病原体免受抗 Arp 抗体的侵害。结果表明，只有当表达 VlsE 时，螺旋体才能成功感染被动免疫的小鼠。随后的免疫荧光测定显示，VlsE 阻止了 Arp 特异性抗体的结合，从而解释了 Arp 抗血清未能清除感染的原因。结果还表明，VlsE 的屏蔽作用并非针对所有伯氏疏螺旋体细胞表面抗原都是通用的。这里报道的结果代表了通过可能的表位屏蔽机制，直接证明了 VlsE 介导对特定伯氏疏螺旋体表面抗原的保护。
