title: Prevalence and activation phenotype of Sendai virus-specific CD4+ T cells.
abstract: The relative prevalence of Sendai virus-specific CD4+ T helper precursors (Thp) has been assessed by limiting dilution analysis (LDA). Within 10 days after intranasal inoculation of C57BL/6 mice, Thp prevalence increased from < 1 in 10(5) to approximately 1 in 200 in CD4+ T-cell-enriched spleen and mediastinal lymph node populations. These frequencies remained elevated relative to naive animals, with the majority of the Thp recovered at 2-3 months after infection being found in the spleen. The "memory" Thp express an "activated" L-selectin-low, CD44-high, alpha 4-integrin-high phenotype, comparable to that described previously for CD8+ cytotoxic T lymphocyte precursors (CTLp) specific for Sendai virus. Background effects for the IL-2-based Thp analysis are, however, less predictable than those found previously for the 51Cr release CTLp LDA, as the extent of non-virus-specific lymphokine production varies. However, provided the analysis is appropriately controlled, the approach does allow useful comparisons between phenotypically different subsets of antigen-specific CD4+ T cells.
authors.affiliation: Department of Immunology, St. Jude Children's Research Hospital, Memphis, Tennessee 38105, USA.
authors.forename: C
authors.initials: C
authors.lastname: Ewing
authors.forename: D J
authors.initials: DJ
authors.lastname: Topham
authors.forename: P C
authors.initials: PC
authors.lastname: Doherty
mesh_terms: D000818:Animals; D000938:Antigen-Presenting Cells / Q000276:immunology; D015704:CD4 Antigens / Q000032:analysis; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology* / Q000821:virology*; D002352:Carrier Proteins / Q000032:analysis; D002478:Cells, Cultured; D005260:Female; D018960:Hyaluronan Receptors; D016130:Immunophenotyping; D009980:Influenza A virus / Q000276:immunology*; D017493:Leukocyte Common Antigens / Q000032:analysis; D008213:Lymphocyte Activation; D008212:Lymphocyte Depletion; D051379:Mice; D008810:Mice, Inbred C57BL; D009976:Orthomyxoviridae Infections / Q000276:immunology*; D010222:Parainfluenza Virus 1, Human / Q000276:immunology*; D011956:Receptors, Cell Surface / Q000032:analysis; D016201:Receptors, Lymphocyte Homing / Q000032:analysis; D012044:Regression Analysis; D013154:Spleen / Q000276:immunology; D013997:Time Factors
chemical_list: D015704:CD4 Antigens; D002352:Carrier Proteins; D018960:Hyaluronan Receptors; D011956:Receptors, Cell Surface; D016201:Receptors, Lymphocyte Homing; D017493:Leukocyte Common Antigens