title: A potential role for CD69 in thymocyte emigration.
abstract: The early activation marker, CD69, is transiently expressed on activated mature T cells and on thymocytes that are undergoing positive or negative selection in the thymus. CD69 is a member of the NK gene complex family of C-type lectin-like signaling receptors; however, its function is unknown. In this report, we describe the characterization of mice that constitutively express high levels of surface CD69 on immature and mature T cells throughout development. Constitutive surface expression of CD69 did not affect T cell maturation, signaling through the TCR or thymocyte selection. However, phenotypically and functionally mature thymocytes accumulated in the medulla of CD69 transgenic mice and failed to be exported from the thymus. The retention of mature thymocytes correlated with transgene dose and CD69 surface levels. These results identify a potential role for CD69 in controlling thymocyte export, and suggest that the transient expression of CD69 on thymocytes and T cells may function to regulate thymocyte and T cell trafficking.
authors.affiliation: Laboratory of Mammalian Genes and Development, National Institute of Child Health and Human Development, Bethesda, MD 20892, USA.
authors.forename: Chiguang
authors.initials: C
authors.lastname: Feng
authors.forename: Kenneth J
authors.initials: KJ
authors.lastname: Woodside
authors.forename: Barbara A
authors.initials: BA
authors.lastname: Vance
authors.forename: Dalal
authors.initials: D
authors.lastname: El-Khoury
authors.forename: Matilde
authors.initials: M
authors.lastname: Canelles
authors.forename: Jan
authors.initials: J
authors.lastname: Lee
authors.forename: Ronald
authors.initials: R
authors.lastname: Gress
authors.forename: B J
authors.initials: BJ
authors.lastname: Fowlkes
authors.forename: Elizabeth W
authors.initials: EW
authors.lastname: Shores
authors.forename: Paul E
authors.initials: PE
authors.lastname: Love
mesh_terms: D000818:Animals; D015703:Antigens, CD / Q000235:genetics / Q000378:metabolism*; D000945:Antigens, Differentiation, T-Lymphocyte / Q000235:genetics / Q000378:metabolism*; D002454:Cell Differentiation; D002465:Cell Movement / Q000276:immunology; D002470:Cell Survival; D006801:Humans; D007700:Kinetics; D037181:Lectins, C-Type; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D008822:Mice, Transgenic; D010641:Phenotype; D016176:T-Lymphocyte Subsets / Q000166:cytology / Q000276:immunology / Q000502:physiology; D013601:T-Lymphocytes / Q000166:cytology / Q000276:immunology* / Q000502:physiology; D013950:Thymus Gland / Q000166:cytology / Q000276:immunology; D000099192:CD69 Antigens
chemical_list: D015703:Antigens, CD; D000945:Antigens, Differentiation, T-Lymphocyte; D037181:Lectins, C-Type; D000099192:CD69 Antigens