title: Cutting edge: virus-specific CD4+ memory T cells in nonlymphoid tissues express a highly activated phenotype.
abstract: Recent studies have shown that CD4(+) memory T cells persist in nonlymphoid organs following infections. However, the development and phenotype of these peripheral memory cells are poorly defined. In this study, multimerized MHC-Ig fusion proteins, with a covalently attached peptide sequence from the Sendai virus hemagglutinin/neuraminidase gene, have been used to identify virus-specific CD4(+) T cells during Sendai virus infection and the establishment of peripheral CD4(+) memory populations in the lungs. We show declining frequencies of virus-specific CD4(+) T cells in the lungs over the course of approximately 3 mo after infection. Like peripheral CD8(+) T cells, the CD4(+) have an acutely activated phenotype, suggesting that a high level of differentiation is required to reach the airways and persist as memory cells. Differences in CD25 and CD11a expression indicate that the CD4(+) cells from the lung airways and parenchyma are distinct memory populations.
authors.affiliation: Trudeau Institute, Saranac Lake, NY 12983, USA.
authors.forename: Linda S
authors.initials: LS
authors.lastname: Cauley
authors.forename: Tres
authors.initials: T
authors.lastname: Cookenham
authors.forename: Timothy B
authors.initials: TB
authors.lastname: Miller
authors.forename: Pamela S
authors.initials: PS
authors.lastname: Adams
authors.forename: Kate M
authors.initials: KM
authors.lastname: Vignali
authors.forename: Dario A A
authors.initials: DA
authors.lastname: Vignali
authors.forename: David L
authors.initials: DL
authors.lastname: Woodland
mesh_terms: D000818:Animals; D015496:CD4-Positive T-Lymphocytes / Q000737:chemistry / Q000276:immunology* / Q000378:metabolism / Q000821:virology*; D018984:Epitopes, T-Lymphocyte / Q000276:immunology*; D005260:Female; D015707:HN Protein / Q000276:immunology; D000949:Histocompatibility Antigens Class II / Q000032:analysis / Q000235:genetics; D007141:Immunoglobulin Fc Fragments / Q000032:analysis / Q000235:genetics; D007156:Immunologic Memory; D016130:Immunophenotyping; D008168:Lung / Q000276:immunology* / Q000378:metabolism / Q000473:pathology / Q000821:virology*; D008213:Lymphocyte Activation; D018655:Lymphocyte Count; D008221:Lymphoid Tissue / Q000276:immunology / Q000473:pathology / Q000821:virology; D051379:Mice; D008810:Mice, Inbred C57BL; D011993:Recombinant Fusion Proteins / Q000032:analysis / Q000096:biosynthesis; D010253:Respirovirus Infections / Q000276:immunology / Q000473:pathology / Q000821:virology; D029082:Sendai virus / Q000276:immunology; D016176:T-Lymphocyte Subsets / Q000276:immunology / Q000378:metabolism / Q000821:virology
chemical_list: D018984:Epitopes, T-Lymphocyte; D015707:HN Protein; D000949:Histocompatibility Antigens Class II; D007141:Immunoglobulin Fc Fragments; D011993:Recombinant Fusion Proteins