J. Virol. doi:10.1128/JVI.02313-07
Copyright (c) 2008, American Society for Microbiology and/or the Listed Authors/Institutions. All Rights Reserved.
The role of T cells in the enhancement of RSV infection severity during adult re-infection of neonatally sensitized mice
John S Tregoning,
Yuko Yamaguchi,
James Harker,
Belinda Wang,
and
Peter JM Openshaw*
Department of Respiratory Medicine, The Centre for Respiratory Infections Research and the MRC & Asthma UK Centre in Allergic Mechanisms of Asthma, National Heart and Lung Institute, Imperial College London, St. Mary's Campus, London W2 1PG, UK
* To whom correspondence should be addressed. Email:
p.openshaw{at}imperial.ac.uk.
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Abstract |
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Respiratory syncytial virus (RSV) is the major cause of infantile bronchiolitis, and hospitalization. Severe RSV disease is associated with the development of wheezing in later life. In a mouse model of the delayed effects of RSV, the age at primary infection determines responses to re-infection in adulthood. During primary RSV infection, neonatal BALB/c mice developed only mild disease and recruited CD8 cells that were defective in interferon gamma production. Secondary re-infection of neonatally primed mice caused enhanced inflammation and profuse lung T cell recruitment. CD4 cell depletion during secondary RSV challenge attenuated disease (measured by weight loss); depletion of CD8 cells also markedly attenuated disease severity but enhanced lung eosinophilia and depleting both CD4 and CD8 cells together completely abrogated weight loss. Depletion of CD8 (but not CD4) cells during primary neonatal infection was protective against weight loss during adult challenge. Therefore, T cells, in particular CD8 T cells, play a central role in the outcome of neonatal infection by enhancing disease during secondary challenge. These findings demonstrate a crucial role for T cells in the regulation of immune responses after neonatal infection.