title: Betaglycan (TβRIII) is expressed in the thymus and regulates T cell development by protecting thymocytes from apoptosis.
abstract: TGF-β type III receptor (TβRIII) is a coreceptor for TGFβ family members required for high-affinity binding of these ligands to their receptors, potentiating their cellular functions. TGF-β [1]-[3], bone morphogenetic proteins (BMP2/4) and inhibins regulate different checkpoints during T cell differentiation. Although TβRIII is expressed on hematopoietic cells, the role of this receptor in the immune system remains elusive. Here, we provide the first evidence that TβRIII is developmentally expressed during T cell ontogeny, and plays a crucial role in thymocyte differentiation. Blocking of endogenous TβRIII in fetal thymic organ cultures led to a delay in DN-DP transition. In addition, in vitro development of TβRIII(-/-) thymic lobes also showed a significant reduction in absolute thymocyte numbers, which correlated with increased thymocyte apoptosis, resembling the phenotype reported in Inhibin α (-/-) thymic lobes. These data suggest that Inhibins and TβRIII may function as a molecular pair regulating T cell development.
authors.affiliation: Departamento de Inmunología, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, México, México.
authors.forename: German R
authors.initials: GR
authors.lastname: Aleman-Muench
authors.forename: Valentin
authors.initials: V
authors.lastname: Mendoza
authors.forename: Kaye
authors.initials: K
authors.lastname: Stenvers
authors.forename: Eduardo A
authors.initials: EA
authors.lastname: Garcia-Zepeda
authors.forename: Fernando
authors.initials: F
authors.lastname: Lopez-Casillas
authors.forename: Chander
authors.initials: C
authors.lastname: Raman
authors.forename: Gloria
authors.initials: G
authors.lastname: Soldevila
mesh_terms: D000818:Animals; D017209:Apoptosis; D019610:Cytoprotection; D004622:Embryo, Mammalian / Q000166:cytology / Q000378:metabolism; D005333:Fetus / Q000378:metabolism; D018507:Gene Expression Regulation, Developmental; D051379:Mice; D008810:Mice, Inbred C57BL; D009924:Organ Culture Techniques; D011509:Proteoglycans / Q000037:antagonists & inhibitors / Q000172:deficiency / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D018125:Receptors, Transforming Growth Factor beta / Q000037:antagonists & inhibitors / Q000172:deficiency / Q000235:genetics / Q000378:metabolism*; D017154:Stromal Cells / Q000378:metabolism; D013601:T-Lymphocytes / Q000166:cytology* / Q000378:metabolism; D060168:Thymocytes / Q000166:cytology* / Q000378:metabolism*; D013950:Thymus Gland / Q000166:cytology / Q000196:embryology / Q000378:metabolism*
chemical_list: D011509:Proteoglycans; D012333:RNA, Messenger; D018125:Receptors, Transforming Growth Factor beta; C071736:betaglycan