Abstract
There has been great interest in the ex vivo expansion of human long-term repopulating hematopoietic stem cells (LTR-HSCs) for a variety of clinical applications such as umbilical cord blood transplantation. The glucoprotein130 signal, activated by a complex of interleukin 6 (IL-6) and soluble IL-6 receptor (IL-6/sIL-6R), acts dramatically in synergy with the c-Kit or Flk2/Flt3 signal to expand immature human HSCs. We demonstrate a significant ex vivo expansion of human LTR-HSCs capable of repopulating in newly discovered nonobese diabetes/Shi-severe combined immunodeficient (NOD/Shi-SCID) mice. The proportion of human CD45+ cells in recipient marrow was 10 times higher in animals receiving the cultured cells with stem cell factor, Flk2/Flt3 ligand, thrombopoietin, and IL-6/sIL-6R than in those receiving comparable numbers of fresh cord blood CD34+ cells. The expansion rate provided by this combination was estimated to be 4.2-fold by a limiting dilution method. Addition of IL-3 to the culture with the cytokine combination abrogated the repopulating ability of the expanded cells. The culture method with the IL-6/sIL-6R complex and other cytokines may pave the way for ex vivo expansion of human transplantable HSCs suitable for clinical applications.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
