title: [Protective effect of mutant dihydrofolate reductase gene on human peripheral blood CD34+ cells against methotrexate].
abstract: OBJECTIVE
  To examine if human peripheral blood hematopoietic progenitor cells transduced with mutant dihydrofolate reductase(mDHFR) gene may increase their resistance to metrotrexate(MTX).
  
  
  METHODS
  After enrichment with a high-gradient magnetic cell sorting system(MACS), the peripheral blood CD34+ cells were transfected with supernatant of retrovirus containing human mDHFR cDNA. Colony formation of hematopoietic progenitor cells was utilized to evaluate mDHFR-conferred resistance to MTX. The number of colonies formed from every 500 cells seeded was counted and expressed as the percentage of colony formation.
  
  
  RESULTS
  After the mD-HFR-transduced CD34+ cells had been screened in vitro in medium containing 20 nmol.L-1 MTX for 14 days, the percentage of colony formation of mDHFR cDNA-transduced and of mock-transduced CD34+ cells was 29.4% and 16.3%, respectively (P < 0.01). The resistance to MTX was increased twofold.
  
  
  CONCLUSIONS
  Transduction of mDHFR gene could confer the resistance of human hematopoietic progenitor cells to MTX toxicity.
authors.affiliation: Cancer Institute(Hospital), Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing 100021.
authors.forename: R
authors.initials: R
authors.lastname: Wu
authors.forename: Z
authors.initials: Z
authors.lastname: Yang
authors.forename: J
authors.initials: J
authors.lastname: Liu
mesh_terms: D018952:Antigens, CD34 / Q000032:analysis*; D000964:Antimetabolites, Antineoplastic / Q000633:toxicity*; D019008:Drug Resistance, Neoplasm; D006412:Hematopoietic Stem Cells / Q000187:drug effects*; D006801:Humans; D008727:Methotrexate / Q000633:toxicity*; D009154:Mutation; D013762:Tetrahydrofolate Dehydrogenase / Q000235:genetics*; D014162:Transfection
chemical_list: D018952:Antigens, CD34; D000964:Antimetabolites, Antineoplastic; D013762:Tetrahydrofolate Dehydrogenase; D008727:Methotrexate