科学家发现了一种用药物治疗西尼罗河病毒感染的方法，这种药物最初是为治疗艾滋病病毒感染而设计的，它的工作原理是刺激人体自身的免疫系统。通常由蚊子传播的西尼罗河病毒如今在北美的一些地区流行，每年导致数百人死于脑炎，死者通常是老年人和免疫低下的人。目前这种病毒还没有疫苗。Robyn Klein 及其同事为感染西尼罗河病毒的小鼠注射了一种称为AMD3100的化合物（也被称为Plerixafor），它最初是为了治疗艾滋病病毒而开发的。
PNAS，doi: 10.1073/pnas.0800898105，Erin E. McCandless，Robyn S. Klein
CXCR4 antagonism increases T cell trafficking in the central nervous system and improves survival from West Nile virus encephalitis
Erin E. McCandless*, Bo Zhang†, Michael S. Diamond*,†,‡, and Robyn S. Klein*,†,§,¶
+Author Affiliations
Departments of *Pathology and Immunology,
†Internal Medicine,
‡Molecular Microbiology, and
§Anatomy and Neurobiology, Washington University School of Medicine, St. Louis, MO 63110
Edited by Wayne M. Yokoyama, Washington University School of Medicine, St. Louis, MO, and approved June 3, 2008 (received for review January 28, 2008)
Abstract
The migration of lymphocytes into the CNS during viral encephalitis is hindered by the blood–brain barrier (BBB) such that most infiltrating cells remain localized to perivascular spaces. This sequestration of leukocytes away from the parenchyma is believed to protect the CNS from immunopathologic injury. Infections of the CNS with highly cytopathic neurotropic viruses, such as West Nile virus (WNV), however, require the parenchymal penetration of T lymphocytes for virus clearance and survival, suggesting that perivascular localization might hinder antiviral immune responses during WNV encephalitis. Using human and murine brain specimens from individuals with WNV encephalitis, we evaluated the expression of CXCL12 and its receptor, CXCR4, at the BBB and tested the hypothesis that inhibition of CXCR4 would promote T lymphocyte entry into the CNS parenchyma and increase viral clearance. Antagonism of CXCR4 significantly improved survival from lethal infection through enhanced intraparenchymal migration of WNV-specific CD8+ T cells within the brain, leading to reduced viral loads and, surprisingly, decreased immunopathology at this site. The benefits of enhanced CD8+ T cell infiltration suggest that pharmacologic targeting of CXCR4 may have therapeutic utility for the treatment of acute viral infections of the CNS.