An influence of CD5 on the selection of CD4-lineage T cells.
Combining CD5-null, MHC-deficient and lineage-specific reporter animals, we have investigated the influence of CD5 on positive selection and the choice of CD4- versus CD8-lineage commitment on broad populations of thymocytes. CD5 has no obvious quantitative effect in wild-type mice. In mice lacking MHC class II molecules, however, increased numbers of transitional, class I-selected CD4+ CD8(int) CD3(hi) cells were positively selected in the absence of CD5. Importantly, they were committed to the CD4 lineage. Our results indicate that CD5 negatively regulates the differentiation of CD4-committed cells in suboptimal conditions, thus perhaps serving to tighten the correlation between restriction of the TCR and lineage choice.
Chan
S
S
Institut de Génétique et de Biologie Moléculaire et Cellulaire (CNRS/INSERM/ULP) Illkirch, C.U. de Strasbourg, France.
Waltzinger
C
C
Tarakhovsky
A
A
Benoist
C
C
Mathis
D
D
D000818:Animals; D017252:CD3 Complex / Q000032:analysis; D015704:CD4 Antigens / Q000032:analysis; D016516:CD4-CD8 Ratio; D015496:CD4-Positive T-Lymphocytes / Q000166:cytology* / Q000276:immunology; D018956:CD5 Antigens / Q000502:physiology*; D016827:CD8 Antigens / Q000032:analysis; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology; D002454:Cell Differentiation / Q000276:immunology; D019070:Cell Lineage / Q000276:immunology; D015395:Histocompatibility Antigens Class I / Q000032:analysis; D000949:Histocompatibility Antigens Class II / Q000032:analysis; D051379:Mice; D016176:T-Lymphocyte Subsets / Q000166:cytology* / Q000276:immunology; D013950:Thymus Gland / Q000166:cytology
D017252:CD3 Complex; D015704:CD4 Antigens; D018956:CD5 Antigens; D016827:CD8 Antigens; D015395:Histocompatibility Antigens Class I; D000949:Histocompatibility Antigens Class II