title: In vitro T lymphopoiesis of human and rhesus CD34+ progenitor cells.
abstract: Differentiation of hematopoietic progenitor cells into T lymphocytes generally occurs in the unique environment of the thymus, a feature that has hindered efforts to model this process in the laboratory. We now report that thymic stromal cultures from rhesus macaques can support T-cell differentiation of human or rhesus CD34+ progenitor cells. Culture of rhesus or human CD34+ bone marrow-derived cells depleted of CD34+ lymphocytes on rhesus thymic stromal monolayers yielded CD3+CD4+CD8+, CD3+CD4+CD8-, and CD3+CD4-CD8+ cells after 10 to 14 days. In addition to classical T lymphocytes, a discrete population of CD3+CD8loCD16+CD56+ cells was detected after 14 days in cultures inoculated with rhesus CD34+ cells. CD3+ T cells arising from these cultures were not derived from contaminating T cells present in the CD34+ cells used to inoculate thymic stromal monolayers or from the thymic monolayers, as shown by labeling of cells with the lipophilic membrane dye PKH26. Expression of the recombinase activation gene RAG-2, which is selectively expressed in developing lymphocytes, was detectable in thymic cultures inoculated with CD34+ cells but not in CD34+ cells before thymic culture or in thymic stromal monolayers alone. Reverse transcriptase-polymerase chain reaction analysis of T cells derived from thymic stromal cultures of rhesus and human CD34+ cells showed a polyclonal T-cell receptor repertoire. T-cell progeny derived from rhesus CD34+ cells cultured on thymic stroma supported vigorous simian immunodeficiency virus replication in the absence of exogenous mitogenic stimuli. Rhesus thymic stromal cultures provide a convenient means to analyze T-cell differentiation in vitro and may be useful as a model of hematopoietic stem cell therapy for diseases of T cells, including acquired immunodeficiency syndrome.
authors.affiliation: Division of Immunology, New England Regional Primate Research Center, Harvard Medical School, Southborough, MA 01772, USA.
authors.forename: M
authors.initials: M
authors.lastname: Rosenzweig
authors.forename: D F
authors.initials: DF
authors.lastname: Marks
authors.forename: H
authors.initials: H
authors.lastname: Zhu
authors.forename: D
authors.initials: D
authors.lastname: Hempel
authors.forename: K G
authors.initials: KG
authors.lastname: Mansfield
authors.forename: P K
authors.initials: PK
authors.lastname: Sehgal
authors.forename: S
authors.initials: S
authors.lastname: Kalams
authors.forename: D T
authors.initials: DT
authors.lastname: Scadden
authors.forename: R P
authors.initials: RP
authors.lastname: Johnson
mesh_terms: D000818:Animals; D018952:Antigens, CD34 / Q000032:analysis; D001483:Base Sequence; D001854:Bone Marrow Cells; D017252:CD3 Complex / Q000032:analysis; D002454:Cell Differentiation; D002478:Cells, Cultured; D003238:Connective Tissue / Q000502:physiology; D003239:Connective Tissue Cells; D018076:DNA, Complementary / Q000235:genetics; D004268:DNA-Binding Proteins; D006410:Hematopoiesis; D006412:Hematopoietic Stem Cells / Q000166:cytology*; D006801:Humans; D008253:Macaca mulatta / Q000502:physiology*; D008969:Molecular Sequence Data; D009687:Nuclear Proteins; D016133:Polymerase Chain Reaction; D011506:Proteins / Q000235:genetics / Q000502:physiology; D017452:Receptors, IgG / Q000032:analysis; D015302:Simian Immunodeficiency Virus / Q000502:physiology; D013045:Species Specificity; D016176:T-Lymphocyte Subsets / Q000166:cytology* / Q000821:virology; D013950:Thymus Gland / Q000166:cytology*
chemical_list: D018952:Antigens, CD34; D017252:CD3 Complex; D018076:DNA, Complementary; D004268:DNA-Binding Proteins; D009687:Nuclear Proteins; D011506:Proteins; C499311:RAG2 protein, human; D017452:Receptors, IgG; C064655:V(D)J recombination activating protein 2