Comparison of two cryopreservation method according to stem cell viability and colony forming capacity [İki kriyoprezervasyon metodunun kök hücre canliliǧi ve koloni oluşturma kapasitesi yönünden karşilaştirilmasi]

Abstract

Peripheral blood stem cells (PBSCs) are usually cryopreserved with rate-controlled programmed freezing (RCPF). However, this method is expensive and time consuming. A simplified method named mechanical freezing (MF) for cryopreservation of PBSCs at -80°C without rate-controlled freezing has been developed for cryopreservation. In this study cell viability, colony forming potential and CD34(+) cell loss after thawing of cryopreserved PBSC with RCPF and MF methods were compared. Six subject's PBSCs were cryopreserved with RCPF while 19 subject's PBSCs were cryopreserved with MF. There was no significant difference between the cell viability and 14th day colony count, just after and 1 hour after thawing in RCPF. The cell viability and colony forming potential of PBSCs, cryopreserved with MF decreased significantly one hour after thawing. When the two methods are compared, the cell viability and colony forming potential was better with RCPF just after and 1 hour after thawing. In conclusion, we observed that in RCPF the viability and hematopoietic activity of PBSC is well preserved and the stem cell viability does not decrease in room temperature for one hour. In the light of these results it is suggested to continue cryopreservation with RCPF.