In Vivo Selection of Human Hematopoietic Cells in a Xenograft Model Using Combined Pharmacologic and Genetic Manipulations

Karen E. Pollok, Jennifer R. Hartwell, Annemarije Braber, Ryan J. Cooper, Michael Jansen, Susanne Ragg, Barbara J. Bailey, Leonard C. Erickson, Emiko L. Kreklau, David A. Williams

Research output: Contribution to journalArticle

35 Scopus citations


Strategies that increase the ability of human hematopoietic stem and progenitor cells to repair alkylator-induced DNA damage may prevent the severe hematopoietic toxicity in patients with cancer undergoing high-dose alkylator therapy. In the context of genetic diseases, this approach may allow for selection of small numbers of cells that would not otherwise have a favorable growth advantage. No studies have tested this approach in vivo using human hematopoietic stem and progenitor cells. Human CD34+ cells were transduced with a bicistronic oncoretrovirus vector that coexpresses a mutant form of O6-methylguanine DNA methyltransferase (MGMT P140K) and the enhanced green fluorescent protein (EGFP) and transplanted into nonobese diabetic/severe combined immunodeficient (NOD/SCID) mice. Mice were either not treated or treated with O6-benzylguanine (6BG) and 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU). At 8-weeks postinjection, a 2- to 8-fold increase in the percentage of human CD45+EGFP + cells in 6BG/BCNU-treated versus nontreated mice was observed in the bone marrow and was associated with increased MGMTP140K-repair activity. Functionally, 6BG/BCNU-treated mice demonstrated multilineage differentiation in vivo, although some skewing in the maturation of myeloid and B cells was observed in mice transplanted with granulocyte-colony stimulating factor (G-CSF)-mobilized peripheral blood compared to umbilical cord blood. Expansion of human cells in 6BG/BCNU-treated mice was observed in the majority of mice previously transplanted with transduced umbilical cord blood cells. In addition, a significant increase in the number of EGFP+ progenitor colonies in treated versus nontreated mice were observed in highly engrafted mice indicating that selection and maintenance of human progenitor cells can be accomplished by expression of MGMTP140K and treatment with 6BG/BCNU.

Original languageEnglish (US)
Pages (from-to)1703-1714
Number of pages12
JournalHuman gene therapy
Issue number18
StatePublished - Dec 10 2003


ASJC Scopus subject areas

  • Molecular Medicine
  • Molecular Biology
  • Genetics

Cite this

Pollok, K. E., Hartwell, J. R., Braber, A., Cooper, R. J., Jansen, M., Ragg, S., Bailey, B. J., Erickson, L. C., Kreklau, E. L., & Williams, D. A. (2003). In Vivo Selection of Human Hematopoietic Cells in a Xenograft Model Using Combined Pharmacologic and Genetic Manipulations. Human gene therapy, 14(18), 1703-1714.