Bone morphogenetic protein-2/4 signalling pathway components are expressed in the human thymus and inhibit early T-cell development.
T-cell differentiation is driven by a complex network of signals mainly derived from the thymic epithelium. In this study we demonstrate in the human thymus that cortical epithelial cells produce bone morphogenetic protein 2 (BMP2) and BMP4 and that both thymocytes and thymic epithelium express all the molecular machinery required for a response to these proteins. BMP receptors, BMPRIA and BMPRII, are mainly expressed by cortical thymocytes while BMPRIB is expressed in the majority of the human thymocytes. Some thymic epithelial cells from cortical and medullary areas express BMP receptors, being also cell targets for in vivo BMP2/4 signalling. The treatment with BMP4 of chimeric human-mouse fetal thymic organ cultures seeded with CD34+ human thymic progenitors results in reduced cell recovery and inhibition of the differentiation of human thymocytes from CD4- CD8- to CD4+ CD8+ cell stages. These results support a role for BMP2/4 signalling in human T-cell differentiation.
Cejalvo
Teresa
T
Department of Cell Biology, Faculty of Biology, Complutense University, Madrid, Spain.
Sacedón
Rosa
R
Hernández-López
Carmen
C
Diez
Blanca
B
Gutierrez-Frías
Cruz
C
Valencia
Jaris
J
Zapata
Agustín G
AG
Varas
Alberto
A
Vicente
Angeles
A
D000818:Animals; D055396:Bone Morphogenetic Protein 2; D055415:Bone Morphogenetic Protein 4; D052004:Bone Morphogenetic Protein Receptors / Q000378:metabolism; D019485:Bone Morphogenetic Proteins / Q000096:biosynthesis / Q000276:immunology*; D002454:Cell Differentiation / Q000276:immunology; D002478:Cells, Cultured; D002675:Child, Preschool; D006801:Humans; D007223:Infant; D051379:Mice; D016513:Mice, SCID; D009924:Organ Culture Techniques; D012333:RNA, Messenger / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods; D015398:Signal Transduction / Q000276:immunology; D051896:Smad Proteins, Receptor-Regulated / Q000235:genetics / Q000378:metabolism; D013601:T-Lymphocytes / Q000166:cytology / Q000276:immunology*; D013950:Thymus Gland / Q000276:immunology*; D016212:Transforming Growth Factor beta / Q000096:biosynthesis / Q000276:immunology*
C525718:BMP2 protein, human; C525809:BMP4 protein, human; C525719:Bmp2 protein, mouse; C525810:Bmp4 protein, mouse; D055396:Bone Morphogenetic Protein 2; D055415:Bone Morphogenetic Protein 4; D019485:Bone Morphogenetic Proteins; D012333:RNA, Messenger; D051896:Smad Proteins, Receptor-Regulated; D016212:Transforming Growth Factor beta; D052004:Bone Morphogenetic Protein Receptors