title: The early kinetics of cytomegalovirus-specific CD8+ T-cell responses are not affected by antigen load or the absence of perforin or gamma interferon.
abstract: Both innate and adaptive immune responses participate in the control of murine cytomegalovirus (mCMV) infection. In some mouse strains, like BALB/c, the control of infection relies on the activities of CD8(+) T cells. mCMV-specific CD8(+) T-cell responses are unusual in that, even after mCMV has been controlled in the periphery, the numbers of circulating virus-specific CD8(+) T cells remain high compared to those observed in other viral infections. To better understand the generation and maintenance of mCMV-specific CD8(+) T-cell responses, we evaluated how antigen load and effector molecules, such as perforin (Prf) and gamma interferon (IFN-gamma), influence these responses during acute infection in vivo. Viral burden affected the magnitude, but not the early kinetics, of antigen-specific CD8(+) T-cell responses. Similarly, the magnitude of virus-specific CD8(+) T-cell expansion was affected by Prf and IFN-gamma, but contraction of antigen-specific responses occurred normally in both Prf- and IFN-gamma-deficient mice. These data indicate that control of mCMV-specific CD8(+) T-cell expansion and contraction is more complex than anticipated and, despite the role of Prf or IFN-gamma in controlling viral replication, a full program of T-cell expansion and contraction can occur in their absence.
authors.affiliation: Immunology and Virology Program, Centre for Ophthalmology and Visual Science, The University of Western Australia, Western Australia, Australia.
authors.forename: Daniel M
authors.initials: DM
authors.lastname: Andrews
authors.forename: Christopher E
authors.initials: CE
authors.lastname: Andoniou
authors.forename: Peter
authors.initials: P
authors.lastname: Fleming
authors.forename: Mark J
authors.initials: MJ
authors.lastname: Smyth
authors.forename: Mariapia A
authors.initials: MA
authors.lastname: Degli-Esposti
mesh_terms: D000818:Animals; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology*; D005434:Flow Cytometry; D006566:Herpesviridae Infections / Q000276:immunology*; D007371:Interferon-gamma / Q000276:immunology*; D007700:Kinetics; D008099:Liver / Q000821:virology; D008168:Lung / Q000821:virology; D016131:Lymphocyte Subsets / Q000276:immunology; D051379:Mice; D008807:Mice, Inbred BALB C; D018345:Mice, Knockout; D018146:Muromegalovirus / Q000276:immunology*; D054353:Perforin / Q000276:immunology*; D012469:Salivary Glands / Q000821:virology; D013154:Spleen / Q000821:virology
chemical_list: D054353:Perforin; D007371:Interferon-gamma