The comparison of different protocols for expansion of umbilical‐cord blood hematopoietic stem cells

Abstract

Hematopoiesis is maintained by the activity of multipotent stem cells, which have the dual capacity to self‐renew and to differentiate into all of the blood cell lineages. The major challenge of stem cells based regenerative therapy is to expand ex vivo the primitive compartment to increase transplantable stem cells number. The present study was designed to evaluate several culture systems for in vitro maintenance of umbilical cord blood stem cells. The influences of different growth conditions such as stromal feeder layer, cytokines supplement and placental conditioned medium (PCM) have been evaluated over a relatively short period of time on CD34+ cell expansion and maintenance of clonogenic progenitors. When cells were expanded on feeder layer in the presence of added cytokines and PCM on average a 2.96‐fold increase of CD34+CD71‐ and a 3.13‐fold increase of CD34+HLA‐DR‐ was observed. The total number of colony forming cells (35±2.65) indicated also that the yield of clonogenic progenitors obtained with a combination of all factors was two folds higher than each of these factors alone and ten time above control (3.67± 2.52). In conclusion, the results of our study clearly show that the ex vivo expansion of hematopoietic progenitor cells obtained from human umbilical cord blood is dependent on controlled experimental conditions, which might be helpful when designing culture systems for clinical applications.

Combination of low O2 concentration and mesenchymal stromal cells during culture of cord blood CD34+ cells improves the maintenance and proliferative capacity of hematopoietic stem cells

“…As a matter of fact, the invention of ''long-term cultures'' (Dexter et al, 1977;Winkler et al, 2010) was based on this approach. Recently, lots of articles were published (Li et al, 2007;Magin et al, 2009;Walenda et al, 2010) evaluating the potential advantages of these co-cultures with respect to liquid cultures in terms of ex vivo expansion of progenitor and stem cells (Yamaguchi et al, 2002;Chivu et al, 2004;McNiece et al, 2004;Wang et al, 2004;Zhang et al, 2004;Robinson et al, 2006;Van OverstraetenSchlö gel et al, 2006;Fei et al, 2007;Huang et al, 2007). The results mainly agreed that the presence of stromal cells provides a better maintenance of stem cell potential.…”

Comparative quantification of umbilical cord blood CD34+ and CD34+ bright cells using the ProCount™-BD and ISHAGE protocols

“…The hematopoietic stem cell has great capacity for self-renewal and cellular proliferation. CD34 molecules, together with the presence of FLT3 and Thy 1 and the absence of HLA-DR, CD38 and specific line markers, are cellular labels used in the identification of primitive classes of stem cells (1)(2)(3)(4)(5)(6)(7).…”

Combination of Early and Late Growth Factors to Enrich Transplantable Cord Blood CD34+ Cells in Short Term Cultures

“…[20][21][22][23] Iden ti fi ca ti on of con di ti ons that sup port the self-re ne wal and ex pan si on of hu man HSC has stimu la ted con si de rab le in te rest in the bi o logy of cord blo od cell s' ex vi vo ex pan si on in va ri o us in vit ro cul tu re systems. 24,25 To en han ce the ra pi dity of en graft ment and iso la ti on and ac ti va ti on of se lec ted im mu ne cell popu la ti ons for pre ven ti on or tre at ment of acu te GvHD, in fec ti o us comp li ca ti ons and tu mor re-occur ren ce, se ve ral are as of on go ing re se arch inc lu de ex vi vo ex pan si on of cord blo od he ma to po i e tic proge ni tor cells. 26 In this study, we used first ti me a wi de ar ray of a growth fac tor com bi na ti on such as IL-3, IL-6, IL-11, SCF, FL and Tpo and ai med to de ter mi ne the effects of the early and la te growth fac tors on CD34 + he ma to po i e tic pro ge ni tor cells, co lony for ming abi lity of the cells in short term sus pen si on cul tu re.…”