Aging is associated with dysregulation of innate and adaptive immunity, which impairs an individual's ability to control infection by newly encountered pathogens. Aging also impacts neuroprotective mechanisms within the central nervous system (CNS), including the function of the blood-brain barrier (BBB), which limits the entry and replication of neutrotropic viruses. West Nile virus (WNV) is the leading cause of arthropod-transmitted viral infections in the United States. While most WNV infections are asymptomatic, individuals with symptomatic disease present either with a flu-like febrile illness that can progress to severe neuroinvasive diseases including meningitis, encephalitis, or flaccid paralysis. Severe WNV infection, especially fatal forms, predominate in the elderly. It is unclear whether this is due to effects of aging on viral invasion and/or virologic control within peripheral tissues or the CNS. To study many different aspects of immune regulation in adult mice, the Diamond and Klein laboratories have established a murine model of infection with a virulent WNV strain. However, interactions between antiviral immunity, neuroinflammation, and aging within the CNS have not been investigated. In this proposal, we will examine the impact of age on innate and adaptive immune mechanisms that control viral entry and clearance specifically within the CNS. The UH2 phase we will establish breeding cohorts and determine the feasibility of using 21 month-old aged animals in WNV infection studies. In the UH3 phase, we will explore how changes in skin immunity, BBB integrity, and CNS inflammation during aging influence neuroinvasion and disease progression associated with WNV infection.

Public Health Relevance

Elderly individuals are more vulnerable to severe neurological disease associated with WNV infection. The development of new aging mouse model of WNV infection may lead to an improved understanding how aging impacts local and CNS immune responses. This could foster new strategies for the prevention and treatment of WNV infection in the elderly, and possibly other infectious and autoimmune conditions in the CNS.

Agency
National Institute of Health (NIH)
Institute
National Institute of Neurological Disorders and Stroke (NINDS)
Type
Exploratory/Developmental Cooperative Agreement Phase II (UH3)
Project #
4UH3NS100126-03
Application #
9738355
Study Section
Special Emphasis Panel (ZRG1)
Program Officer
Zhang, Ran
Project Start
2016-09-30
Project End
2021-06-30
Budget Start
2018-08-01
Budget End
2019-06-30
Support Year
3
Fiscal Year
2018
Total Cost
Indirect Cost
Name
Washington University
Department
Internal Medicine/Medicine
Type
Schools of Medicine
DUNS #
068552207
City
Saint Louis
State
MO
Country
United States
Zip Code
63130