Extrathymic T cell differentiation in vitro from human CD34+ stem cells.
Although it is well established that T cells are derived from CD34+ stem cells in vivo, and that T cells can develop in the absence of a functioning thymus, it has not proven possible thus far to generate human T cells in vitro from CD34+ cells in the absence of any thymic influence. We now present a limiting dilution cloning culture system that supports the differentiation of highly purified human CD34+ cells to CD3+ T cells in vitro in the complete absence of any thymic components. The culture system features the use of a serum-free medium supplemented with a cocktail of cytokines including flt-3 ligand, interleukin-3 (IL-3), stem cell factor (SCF), and IL-2. CD4+ T cell clones capable of mitogen-stimulated proliferation and response to IL-2, and expressing a varied TCR-Vbeta repertoire were obtained under these conditions. This culture system therefore supports human T lymphopoiesis in the absence of any thymic influence and may prove useful for the evaluation of extrathymic T cell differentiation in vitro.
Pawelec
G
G
Department of Hematology, Oncology, Immunology and Rheumatology, Tübingen University Medical School, Germany. graham.pawelec@med.uni-tuebingen.de
Müller
R
R
Rehbein
A
A
Hähnel
K
K
Ziegler
B L
BL
D000818:Animals; D018952:Antigens, CD34; D000954:Antigens, Surface / Q000032:analysis; D002417:Cattle; D002454:Cell Differentiation / Q000276:immunology; D002455:Cell Division / Q000276:immunology; D002478:Cells, Cultured; D002999:Clone Cells; D016207:Cytokines / Q000096:biosynthesis / Q000502:physiology; D005312:Fetal Blood / Q000502:physiology; D006801:Humans; D009928:Organ Specificity / Q000276:immunology; D016693:Receptors, Antigen, T-Cell, alpha-beta / Q000032:analysis; D013234:Stem Cells / Q000166:cytology* / Q000276:immunology / Q000378:metabolism; D016176:T-Lymphocyte Subsets / Q000166:cytology* / Q000276:immunology / Q000378:metabolism; D013950:Thymus Gland / Q000166:cytology
D018952:Antigens, CD34; D000954:Antigens, Surface; D016207:Cytokines; D016693:Receptors, Antigen, T-Cell, alpha-beta