Detection of a high frequency of virus-specific CD4+ T cells during acute infection with lymphocytic choriomeningitis virus.
Lymphocytic choriomeningitis virus (LCMV), like many viruses, induces a profound activation and expansion of CD8+ T cells. In contrast, CD4+ T cells do not increase in total number during the acute infection. We show here that mice infected with LCMV have a low but detectable frequency (<1/300) of CD4+ T cells, as detected by IL-2 production in limiting dilution assays, to each of two class II peptides during the peak of the acute LCMV response and into long-term memory. However, during the peak of the acute CD4+ T cell response, >20% of the CD4+ T cells secreted IFN-gamma after stimulation with PMA and ionomycin, and >10% of the CD4+ T cells secreted IFN-gamma after stimulation with the LCMV peptides. Thus, these new sensitive assays reveal a heretofore unappreciated, yet profound Ag-specific CD4+ T cell response during viral infections.
Department of Pathology, University of Massachusetts Medical Center, Worcester 01655, USA.
S M
SM
Varga
R M
RM
Welsh
D000208:Acute Disease; D000818:Animals; D015496:CD4-Positive T-Lymphocytes / Q000737:chemistry / Q000276:immunology* / Q000378:metabolism / Q000821:virology*; D018984:Epitopes, T-Lymphocyte / Q000276:immunology; D007371:Interferon-gamma / Q000096:biosynthesis; D007424:Intracellular Fluid / Q000737:chemistry / Q000378:metabolism; D018655:Lymphocyte Count; D008216:Lymphocytic Choriomeningitis / Q000276:immunology* / Q000378:metabolism / Q000821:virology; D008217:Lymphocytic choriomeningitis virus / Q000276:immunology*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D010455:Peptides / Q000276:immunology; D013194:Staining and Labeling; D013234:Stem Cells / Q000276:immunology; D014764:Viral Proteins / Q000276:immunology
D018984:Epitopes, T-Lymphocyte; D010455:Peptides; D014764:Viral Proteins; D007371:Interferon-gamma