1. Cryopreservation of Stem Cells Using Human Serum Albumin and
Autologus Plasma as Cryoprotectants: Its Clinical Impact
Mohandoss Murugesan1, Chandran K Nair2
Transfusion Medicine1, Clinical Hematology2,
Malabar Cancer Centre, Thalassery, Kannur Dt., Kerala
(An autonomous center under Govt. of Kerala)
Background
Cryopreservation of stem cells in autologous hematopoietic stem cell transplantation (HSCT) was performed to maintain their cell viability and recovery during storage. Commonly followed practice was to dilute cryoprotectant DMSO with Human serum albumin (HSA) for achieving optimal concentration. Autologous Plasma (AP) is less expensive and ready availability makes it an easy alternative for HSA in preparing cryoprotective solutions.
Aim: To study the process of using human serum albumin and autologous plasma as diluents for DMSO in autologous transplantation and to compare the impact of both cryoprotective solutions on hematopoietic engraftment
Methods:
Retrospective study, involving 15 autologous HSCT patients, who underwent cryopreservation. Two study groups
The 15% cryoprotectants added in equal volume to the PBSC product to yield a final concentration of 7.5 %.
Quantification of CD34+ cells: by flow cytometry using FC500 (Ishage protocol)
Volume Reduction (VR): All the product were centrifuged at x5000g and supernatant plasma separated. In AP group, the plasma was used for dilution of DMSO.
Engraftment Interval: Hematopoietic reconstitution in two groups studied.
Transfusion Support: data retrieved
Group I (n=7 patients)
DMSO diluted by human serum albumin
Group II (n=8 patients)DMSO diluted by autologous plasma (harvested during leukapheresis & volume reduction of final product)
Volume of HSA/AP required = F * 85/100
Volume of DMSO required = F * 15/100
Results: 6/15 patients underwent stem cell infusion and taken for analysis
Patient
characteristic 5%
HSA
Auto
Plasma
Male
/Female
7/0
5/3
Age 32
(14-50) 47
(19-62)
Diagnosis MM HD
NHL
Others 3 1 2 5
CD34+cells
(x106/kg)
7.2
(2.1-12)
4.4
( )
Viability % 86 90
Product
volume 5%
HSA
Auto
Plasma
Before VR
278
±48
314
±74
After
170
±66
193
±42
Median Tx 5%
HSA
Auto
Plasma
PRBC 5
(0-5) 3
(1-5)
PLT tx
events
(2-3) 6
(2-7)
Median Engraftment
Days (Range) 5%
HSA
Auto
Plasma
WBC> 1x109/L
9 (9-10)
11 (9-16)
ANC > 0.5x109/L
3 consecutive days
PLT>20x109/L
without tx
15 (13-25)
27 (12-28)
Discussion & Conclusion
Smagur et.al, had shown HSA can be replaced by AP without negative impact on cell recovery and clonogenic potential. This study supports that the autologous plasma can be a easier & cheaper alternative to HSA in cryopreservation of HSCs. We refrain from drawing any conclusions from this study due to the insufficient sample and further studies are being carried out.
References: Smagur A, Mitrus I, Ciomber A et al. Comparison of the cryoprotective solutions based on human albumin vs. autologus plasma: its effect on cell recovery, clonogenic potential of peripheral blood hematopoietic progenitor cells and engraftment after autologous transplantation. Vox Sanguinis (2015) 108, 417–424