Requirement for CD4(+) T cells in V beta 4(+)CD8(+) T cell activation associated with latent murine gammaherpesvirus infection

Citation
E. Flano et al., Requirement for CD4(+) T cells in V beta 4(+)CD8(+) T cell activation associated with latent murine gammaherpesvirus infection, J IMMUNOL, 163(6), 1999, pp. 3403-3408
Citations number
36
Categorie Soggetti
Immunology
Journal title
JOURNAL OF IMMUNOLOGY
ISSN journal
00221767 → ACNP
Volume
163
Issue
6
Year of publication
1999
Pages
3403 - 3408
Database
ISI
SICI code
0022-1767(19990915)163:6<3403:RFCTCI>2.0.ZU;2-T
Abstract
A CD8(+) T cell lymphocytosis in the peripheral blood is associated with th e establishment of latency following intranasal infection with murine gamma herpesvirus-68. Remarkably, a large percentage of the activated CD8(+) T ce lls of mice expressing different MHC haplotypes express V beta 4(+) TCR, Id entification of the ligand driving the V beta 4(+)CD8(+) T cell activation remains elusive, but there is a general correlation between V beta 4(+)CD8( +) T cell stimulatory activity and establishment of latency in the spleen. In the current study, the role of CD4(+) T cells in the V beta 4(+)CD8(+) T cell expansion has been addressed. The results show that CD4(+) T cells ar e essential for expansion of the V beta 4(+)CD8(+) subset, but not other V beta subsets, in the peripheral blood. CD4(+) T cells are required relative ly late in the antiviral response, between 7 and 11 days after infection, a nd mediate their effect independently of IFN-gamma, Assessment of V beta 4( +)CD8(+) T cell stimulatory activity using murine gammaherpesvirus-68-speci fic T cell hybridomas generated from latently infected mice supports the id ea that CD4(+) T cells control levels of the stimulatory ligand that drives the V beta 4(+)CD8(+) T cells. As V beta 4(+)CD8(+) T cell expansion also correlates with levels of activated B cells, these data raise the possibili ty that CD4(+) T cell-mediated B cell activation is required for optimal ex pression of the stimulatory ligand. In addition, in cases of low ligand exp ression, there may also be a direct role for CD4(+) T cell-mediated help fo r V beta 4(+)CD8(+) T cells.