Characterization in vitro and engraftment potential in vivo of human progenitor T cells generated from hematopoietic stem cells

Blood. 2009 Jul 30;114(5):972-82. doi: 10.1182/blood-2008-10-187013. Epub 2009 Jun 2.

Abstract

T-cell development follows a defined set of stage-specific differentiation steps. However, molecular and cellular events occurring at early stages of human T-cell development remain to be fully elucidated. To address this, human umbilical cord blood (UCB) hematopoietic stem cells (HSCs) were induced to differentiate to the T lineage in OP9-DL1 cocultures. A developmental program involving a sequential and temporally discrete expression of key differentiation markers was revealed. Quantitative clonal analyses demonstrated that CD34(+)CD38(-) and CD34(+)CD38(lo) subsets of UCB contain a similarly high T-lineage progenitor frequency, whereas the frequency in CD34(+)CD38(+/hi) cells was 5-fold lower. Delta-like/Notch-induced signals increased the T-cell progenitor frequency of CD34(+)CD38(-/lo) cells differentiated on OP9-DL1, and 2 distinct progenitor subsets, CD34(+)CD45RA(+)CD7(++)CD5(-)CD1a(-) (proT1) and CD34(+)CD45RA(+)CD7(++)CD5(+)CD1a(-) (proT2), were identified and their thymus engrafting capacity was examined, with proT2 cells showing a 3-fold enhanced reconstituting capacity compared with the proT1 subset. Furthermore, in vitro-generated CD34(+)CD7(++) progenitors effectively engrafted the thymus of immunodeficient mice, which was enhanced by the addition of an IL-7/IL-7 antibody complex. Taken together, the identification of T-progenitor subsets readily generated in vitro may offer important avenues to improve cellular-based immune-reconstitution approaches.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antigen-Antibody Complex / pharmacology
  • Antigens, CD / analysis
  • Cell Lineage
  • Cells, Cultured / cytology
  • Cells, Cultured / transplantation
  • DNA-Binding Proteins / deficiency
  • DNA-Binding Proteins / genetics
  • Fetal Blood / cytology
  • Hematopoietic Stem Cells / cytology*
  • Humans
  • Immunologic Deficiency Syndromes / genetics
  • Immunologic Deficiency Syndromes / immunology
  • Immunologic Deficiency Syndromes / surgery
  • Infant, Newborn
  • Interleukin Receptor Common gamma Subunit / deficiency
  • Interleukin Receptor Common gamma Subunit / genetics
  • Interleukin-7 / immunology
  • Interleukin-7 / pharmacology
  • Lymphopoiesis
  • Mice
  • Mice, Inbred BALB C
  • Mice, Inbred NOD
  • Mice, Knockout
  • Mice, SCID
  • Organ Culture Techniques
  • Specific Pathogen-Free Organisms
  • T-Lymphocyte Subsets / chemistry
  • T-Lymphocyte Subsets / cytology*
  • T-Lymphocyte Subsets / transplantation
  • Thymus Gland / cytology
  • Thymus Gland / embryology
  • Transplantation, Heterologous

Substances

  • Antigen-Antibody Complex
  • Antigens, CD
  • DNA-Binding Proteins
  • IL7 protein, human
  • Interleukin Receptor Common gamma Subunit
  • Interleukin-7
  • Rag2 protein, mouse