Virus dissemination through the brain parenchyma without immunologic control.
After inoculation into the cerebrospinal fluid, the neurovirulent influenza virus A/WSN caused a rapidly progressive encephalitis that was uniformly fatal within 8 days. After inoculation into the brain parenchyma, the same virus replicated for 7 to 20 days without causing clinical illness, but when infection reached the cerebrospinal fluid, encephalitis was lethal within a further 6 days. As the virus spread through the brain parenchyma, there was intense intracerebral inflammation, with up-regulation of MHC class I and MHC class II expression and recruitment of CD44(high) CD49d(high) T cells. However, this was not associated with antiviral Ab production, and the infiltrating cells, unlike primed A/WSN-specific T cells, did not eliminate the virus in vivo or show evidence of virus recognition in vitro. Thus, a neurovirulent virus was able to disseminate widely through the brain parenchyma and induce considerable intracerebral inflammation without eliciting protective immunity.
Stevenson
P G
PG
Nuffield Department of Medicine, John Radcliffe Hospital, Oxford, United Kingdom.
Freeman
S
S
Bangham
C R
CR
Hawke
S
S
D000818:Animals; D000914:Antibodies, Viral / Q000097:blood; D001921:Brain / Q000276:immunology* / Q000821:virology*; D007114:Immunization; D016130:Immunophenotyping; D051379:Mice; D008810:Mice, Inbred C57BL; D009976:Orthomyxoviridae Infections / Q000276:immunology*; D013601:T-Lymphocytes / Q000276:immunology
D000914:Antibodies, Viral