Self-renewal of primitive human hematopoietic cells (long-term-culture-initiating cells) in vitro and their expansion in defined medium.

• DOI: 10.1073/pnas.93.4.1470
• Publication Date: 2002-07-26T14:43:20Z
• Authors: A L Petzer; D E Hogge; P M Landsdorp; D S Reid; C J Eaves
• Keywords: Interleukin 3

A major goal of experimental and clinical hematology is the identification mechanisms conditions that support expansion transplantable hematopoietic stem cells. In normal marrow, such cells appear to be identical (or represent a subset of) population referred as long-term-culture-initiating (LTC-ICs) so-named because their ability produce colony-forming cell (CFC) progeny for > or = 5 weeks when cocultured with stromal fibroblasts. Some LTC-ICs in vitro has recently been described, but factors required whether LTC-IC self-renewal divisions are involved have remained unresolved issues. To address these issues, we examined maintenance and/or generation from single CD34+ CD38- cultured variable periods under different culture conditions. Analysis obtained cultures containing feeder layer murine fibroblasts engineered steel factor, interleukin (IL)-3, granulocyte colony-stimulating factor showed approximately 20% input (representing 2% original cells) executed within 6-week period. Incubation same starting populations defined (serum free) liquid medium supplemented Flt-3 ligand, IL-3, IL-6, nerve growth resulted proliferation initial clones 4 1000 10 days, 40% which included 1 LTC-IC. contrast, similar methylcellulose, appeared persist not divide. Overall was 30-fold first days 50-fold by end another 1-3 weeks. Documentation human permit extensive rapid amplification should facilitate analysis molecular underlying processes exploitation variety therapeutic applications.