西尼罗河病毒感染后小鼠中枢神经系统中病毒特异性免疫应答的持续存在。

BACKGROUND

West Nile virus (WNV) persists in humans and several animal models. We previously demonstrated that WNV persists in the central nervous system (CNS) of mice for up to 6 months post-inoculation. We hypothesized that the CNS immune response is ineffective in clearing the virus.

RESULTS

Immunocompetent, adult mice were inoculated subcutaneously with WNV, and the CNS immune response was examined at 1, 2, 4, 8, 12 and 16 weeks post-inoculation (wpi). Characterization of lymphocyte phenotypes in the CNS revealed elevation of CD19+ B cells for 4 wpi, CD138 plasma cells at 12 wpi, and CD4+ and CD8+ T cells for at least 12 wpi. T cells recruited to the brain were activated, and regulatory T cells (Tregs) were present for at least 12 wpi. WNV-specific antibody secreting cells were detected in the brain from 2 to 16 wpi, and virus-specific CD8+ T cells directed against an immunodominant WNV epitope were detected in the brain from 1 to 16 wpi. Furthermore, these WNV-specific immune responses occurred in mice with and without acute clinical disease.

CONCLUSIONS

Virus-specific immune cells persist in the CNS of mice after WNV infection for up to 16 wpi.

背景

西尼罗河病毒（WNV）在人类和几种动物模型中持续存在。我们之前证明，WNV 在接种后长达 6 个月内持续存在于小鼠的中枢神经系统（CNS）中。我们假设 CNS 免疫反应不能有效清除病毒。

结果

免疫功能正常的成年小鼠经皮下接种 WNV 后，在接种后 1、2、4、8、12 和 16 周（wpi）时检查 CNS 免疫反应。对 CNS 中淋巴细胞表型的特征分析显示，CD19+B 细胞在 4wpi 时升高，CD138 浆细胞在 12wpi 时升高，CD4+和 CD8+T 细胞至少在 12wpi 时升高。募集到大脑的 T 细胞被激活，并且 T 调节细胞（Tregs）至少在 12wpi 时存在。在接种后 2 至 16wpi 时在大脑中检测到针对 WNV 的特异性抗体分泌细胞，并且在接种后 1 至 16wpi 时在大脑中检测到针对 WNV 免疫显性表位的特异性 CD8+T 细胞。此外，这些针对 WNV 的免疫反应发生在有和没有急性临床疾病的小鼠中。