title: T cell development in CD8-/- mice. Thymic positive selection is biased toward the helper phenotype.
abstract: The CD4 and CD8 molecules are involved in T cell differentiation and activation. Nevertheless, efficient thymic maturation of helper T cells has been shown in the absence of the CD4 molecule. These CD4-deficient helper T cells expressed alpha beta-TCR and were able to control Leishmania infections and to mediate Ab class switch. Using mice deficient for the CD8 alpha-chain, we investigated whether a similar cytotoxic T cell population was generated in the absence of the CD8 coreceptor. A CD8-deficient cytotoxic T cell population corresponding to the described CD4-deficient helper T cell population was virtually absent both functionally and physically. These results support the idea that thymic maturation is asymmetrical and strongly biased toward the helper phenotype.
authors.affiliation: Department of Pathology, University of Zürich, Switzerland.
authors.forename: M F
authors.initials: MF
authors.lastname: Bachmann
authors.forename: A
authors.initials: A
authors.lastname: Oxenius
authors.forename: T W
authors.initials: TW
authors.lastname: Mak
authors.forename: R M
authors.initials: RM
authors.lastname: Zinkernagel
mesh_terms: D000818:Animals; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology*; D002454:Cell Differentiation / Q000235:genetics / Q000276:immunology; D003601:Cytotoxicity Tests, Immunologic; D005434:Flow Cytometry; D015395:Histocompatibility Antigens Class I / Q000235:genetics; D000949:Histocompatibility Antigens Class II / Q000235:genetics; D007519:Isoantigens / Q000235:genetics; D008213:Lymphocyte Activation / Q000276:immunology; D008217:Lymphocytic choriomeningitis virus / Q000276:immunology; D051379:Mice; D008810:Mice, Inbred C57BL; D008817:Mice, Mutant Strains; D010641:Phenotype; D006377:T-Lymphocytes, Helper-Inducer / Q000276:immunology*; D014721:Vesicular stomatitis Indiana virus / Q000276:immunology
chemical_list: D015395:Histocompatibility Antigens Class I; D000949:Histocompatibility Antigens Class II; D007519:Isoantigens