Clonogenic capacity andex vivo expansion potential of umbilical cord blood progenitor cells are not impaired by cryopreservation

Abstract

SummaryFetal blood collected immediately after delivery has been was the aim of this study to evaluate whether cryopreshown to contain hematopoietic progenitor cells at similar servation procedures might heavily impair the clonoor higher frequency than those in bone marrow (BM).1 genic capacity, the feasibility of CD34 ؉ selection and the Therefore, umbilical cord blood (UCB), which is normally ex vivo expansion potential of UCB progenitor cells.discarded, has been evaluated as a source of UCB samples were collected and cryopreserved as stem/progenitor cells 2-4 that can easily be collected at delivunseparated (n ‫؍‬ 21) or mononuclear (MNC) cells (n ery without any danger or inconvenience to the donor. 5,6‫؍‬ 15) within 12 h from delivery, and evaluated for Recently, UCB has been used as a source of hematopoietic viability, immunophenotype, cell and progenitor numstem cells for clinical transplantation, and is proving to be bers after a minimum stay in liquid nitrogen of 6 an acceptable alternative to BM. 7-9 Several studies have months (range 6-14 months). Viability was always demonstrated that UCB contains similar or higher pro-Ͼ97% and no statistically significant difference was portions of primitive hematopoietic progenitor cells as detected by flow cytometric analysis. Clonogenic recovcompared to adult BM 2,4 and therefore the lower number ery from unseparated cells was 80-87% for HPP-CFC, of nucleated cells, present in a single collection, might be CFU-GEMM, BFU-E and CFU-GM, and from MNC compensated by a significantly higher proportion of cells ranged from 82 to 91% for LTC-IC, CFU-GEMM, primitive cells. More recently, highly purified BFU-E and CFU-GM. CD34؉ selection (n ‫؍‬ 8) was per-CD34 capacity has made UCB-derived progenitor cells ideal cansignificant difference was detected in CFC fold-expandidates for experimental programs involving gene transfer sion for fresh or cryopreserved MNC cells and for and ex vivo stem cell expansion. Since several programs CD34 ؉ cells, either selected and cultured from fresh or throughout Europe and the USA are currently evaluating cryopreserved MNC cells. In conclusion we can state the feasibility of large-scale UCB banking for unrelated that UCB is a potential source of primitive progenitor transplants 5,12,13 cytokine-mediated ex vivo expansion of cells that can be cryopreserved unmanipulated or after UCB hematopoietic progenitor cells might increase the physical separation without major losses in clonogenic number of progenitor cells to be transplanted and facilitate capacity and immunophenotypic composition. Moreengraftment in adult patients. Therefore, it was the aim of our study to investigate whether cryopreservation can affect the clonogenic capacity, the immunophenotype, the feasi- potential of UCB progenitor cells.

Study on viability and chondrogenic differentiation of cryopreserved adipose tissue-derived mesenchymal stromal cells for future use in regenerative medicine

“…The effects of cryopreservation have been investigated using other types of stem cells [1,22]. These results and our results indicate that the freeze-and-thaw process and long-term storage in liquid nitrogen do not critically alter the phenotype of rat AT-MSCs.…”

Culturing human umbilical cord blood: a comparison of mononuclear vs CD34+ selected cells

“…25 Also, CD34 + selection is expensive, timeconsuming and associated with extensive manipulation. The mononuclear cell fraction of human umbilical cord blood may therefore represent the better starting cell population.…”

Biologic and phenotypic analysis of early hematopoietic progenitor cells in umbilical cord blood

“…[1][2][3] Studies are under way to determine the feasibility of UCB banking for use in unrelated transplants. [3][4][5][6] However, the major concern for future transplant application in adult patients has been related to the low number of progenitor cells that could be obtained by a single UCB collection. Several studies suggested that UCB contains a higher proportion of hematopoietic progenitor cells as compared to adult BM [7][8][9] and therefore the lower number of nucleated cells, present in a single collection, might be compensated by a higher proportion of primitive cells.…”