The Study Of Uncontrolled-rate Freezing And Storage At-80℃for Autologous Peripheral Blood Progenitor Cell Transplantation

Research background and objective: Autologous stem cell transplantation at presentis an effective approach in the treatment of malignant hematologic diseases and tumors.The cryopreservation of PBSC is one of all the important steps. The classic way ofcryopreservation of the hematopoietic progenitor cells with liquid nitrogen andcontrolled-rate freezing requires sophisticated equipment, very well trained staff andhigh cost.104cases of a simplified technique for PBSC cell cryopreservation at-80℃without rate-controlled freezing from PLA General Hospital hematology departmentwill be presented as following. Median duration of cryopreservation was30.5days. Wehope use the research on the recovery rates of MNCs、CD34+cells，cell viability and theimpact factor on them，hematologic reconstitution after transplantation and the impactfactors to evaluate the simple method for cryopreservation.This study was divided into two parts, as follows.Part IMethods: From February2004to May2010,104patients who underwent autologousperipheral blood stem cell transplantation from PLA General Hospital hematologydepartment will be retrospectively analyzed. After the mobilization regimen，stem cellsare collected. The cryoprotect solution contains HAS、5%DMSO and HES. Medianduration of the cryopreservation was30.5days. Median recoveries of MNCs、cellviability、CD34+cell are observed.Result: The median recovery rates of MNCs, CD34+cell are80.3%and86%, cellviability is94%respectively, which are reduced significantly after the freezingprocedure. There are two cases of more than half a year cryopreservation，which sharethe same recoveries of MNCs, cell viability and CD34+cell of short timecryopreservation. Conclusion: Our data about the recoveries of MNCs, cell viability, CD34+cell indicatethat the simple method for stem cell cryopreservation at-80℃with uncontrolled-ratefreezing and with5%DMSO、HES and HAS have a satisfied result. The incidence ofadverse effect is7.7%. The times of chemotherapy and radiotherapy were impact thequality of PBC.Part IIMethods: The median time to reach0.5×109granulocytes per/L，20×109platelets perL of the104patients is observed. The relationship between the dose of CD34+cell andthe time of neutrophil engraftment is analyzed. It will be confirmed that whether thedifferences between different diagnosis, age, gender, radiotherapy or not and the timesof chemotherapy exist.Results: CD34+cells infused was significant for days to ANC＞0.5×109/L，r=-0.292，nosignificant to platelet recovery to＞20×109/L. The time of storage has nosignificant relationship with ANC and platelet recovery. No significant differences existin diagnosis, gender, radiotherapy or not and the times of chemotherapy.Conclusion: The simple uncontrolled-rate freezing of PBSCs at-80℃could beapplied for the cryopreservation of PBSCs for transplantation, which is safe, effective,and could meets clinical needs. Comparing with the classical cryopreservation，nosignificant differences exist in the hematopoietic reconstitution. It is economical in staffand materials.In summary: The simple uncontrolled-rate freezing of PBSCs at-80℃could beapplied for the cryopreservation of PBSCs for transplantation. It is less time-consumingand has lower cost，this method should be widely promoted.