title: Quantification of epitope-specific MHC class-II-restricted T cells following lymphocytic choriomeningitis virus infection.
abstract: CD4(+) T cells are critical for the control of many viruses; however, the numbers of virus-specific CD4(+) cells that are expanded following infection are unknown. We have addressed this issue by enumerating virus-specific, MHC class-II-restricted T cells following infection of mice with lymphocytic choriomeningitis virus (LCMV). We have found that the numbers of T cells that produce interferon-gamma in response to stimulation with three different class-II-restricted LCMV epitopes increase from undetectable numbers in noninfected animals to between 4 x 10(5) and 2 x 10(6) cells per spleen at the peak of the T cell response. This contrasts with the numbers of virus-specific class-I-restricted T cells which expand to 1 x 10(7) to 2 x 10(7) cells per spleen during the same time period. We could not reproducibly detect virus-specific class-I-restricted or class-II-restricted T cells that produced interleukin-4 at any time following LCMV infection, indicating that infection with this virus induces a predominantly type 1 cytokine response. In contrast to the rapid decrease in the numbers of class-I-restricted T cells, the numbers of LCMV-specific class-II-restricted T cells declined gradually following the peak of the T cell response. We demonstrate, therefore, that following infection with LCMV there is expansion of both class-I-restricted and class-II-restricted virus-specific T cells; however, the degree of expansion of class-II-restricted T cells is substantially less than that observed for class-I-restricted cells. Furthermore, the downregulation phase of the class-II-restricted response is protracted compared with the precipitous contraction of the antiviral CD8(+) T cell response.
authors.affiliation: Department of Microbiology and Immunology, Loyola University Chicago, 2160 South First Avenue, Maywood, Illinois 60153, USA.
authors.forename: C
authors.initials: C
authors.lastname: Kamperschroer
authors.forename: D G
authors.initials: DG
authors.lastname: Quinn
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000956:Antigens, Viral / Q000276:immunology*; D016207:Cytokines / Q000302:isolation & purification; D000939:Epitopes; D005802:Genes, MHC Class II / Q000276:immunology*; D006023:Glycoproteins / Q000276:immunology; D007156:Immunologic Memory; D007371:Interferon-gamma / Q000378:metabolism; D018655:Lymphocyte Count; D008216:Lymphocytic Choriomeningitis / Q000276:immunology*; D051379:Mice; D008810:Mice, Inbred C57BL; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000276:immunology; D013154:Spleen / Q000276:immunology; D013601:T-Lymphocytes / Q000276:immunology*; D014764:Viral Proteins / Q000276:immunology
chemical_list: D000956:Antigens, Viral; D016207:Cytokines; D000939:Epitopes; D006023:Glycoproteins; D010446:Peptide Fragments; D014764:Viral Proteins; D007371:Interferon-gamma