A new automated cell washer device for thawed cord blood units.
BACKGROUND
The current available techniques to wash out DMSO from thawed umbilical cord blood (UCB) units are based essentially on standard centrifugation in an open system with various degrees of cell loss.


METHODS
We evaluated the capacity of a new automated closed device (Cytomate, Baxter, IL) to wash out the DMSO from thawed UCB units, saving at the same time the progenitor and accessory cells in terms of CD34+ cells and MNCs. We modified the standard software of the device and calculated the cell recovery on 25 UCB units. Moreover, we set up a new gas chromatographic method to exactly detect the DMSO removal rate.


RESULTS
To evaluate the efficiency of the Cytomate device, we considered the postthawing (prewashing) versus postwashing cell recovery. The average recovery (%) in terms of total nucleated cells was 63.30 (range, 40.12-89.00), CD34+ cells was 70.20 (range, 11.51-89.01), CD3+ cells was 61.01 (range, 28.80-87.08), CD4+ cells was 62.53 (range, 30.62-96.73), CD8+ cells was 57.4 (range, 26.87-94.72), CD19+ cells was 63.33 (range, 39.10-90.33), CD16+/56+ cells was 70.67 (range, 8.91-98.40), CFU-GM was 74.33 (range, 20.23-98.60), total CFUs was 82.34 (range, 14.83-247.12), and viability was 89.67(range, 70.74-98.30). The total working time required was, on average, 15 minutes (range, 7-20).


CONCLUSIONS
The Cytomate device demonstrated a satisfying efficiency in cell recovery and in maintaining the clonogenic power of the UCB graft. The removal rate of DMSO was practically complete with evident advantages for the recipient. Finally, the entire manipulation performed in a closed system revealed to be safe, maintaining the sterility of the graft.
Perotti
Cesare G
CG
Immunohematology and Transfusion Service, Center for Transplant Immunology, IRCCS Policlinico S. Matteo, Pavia, Italy. c.perotti@smatteo.pv.it
Del Fante
Claudia
C
Viarengo
Gianluca
G
Papa
Pietro
P
Rocchi
Loretta
L
Bergamaschi
Paola
P
Bellotti
Laura
L
Marchesi
Andrea
A
Salvaneschi
Laura
L
D001331:Automation; D001772:Blood Cell Count; D001773:Blood Cells / Q000737:chemistry / Q000166:cytology / Q000382:microbiology; D001793:Blood Preservation; D002469:Cell Separation / Q000295:instrumentation* / Q000379:methods; D002498:Centrifugation / Q000295:instrumentation* / Q000379:methods; D002849:Chromatography, Gas / Q000379:methods; D003114:Colony-Forming Units Assay; D015925:Cryopreservation; D003451:Cryoprotective Agents / Q000032:analysis*; D004121:Dimethyl Sulfoxide / Q000097:blood*; D005312:Fetal Blood; D005434:Flow Cytometry; D006801:Humans; D016130:Immunophenotyping; D007231:Infant, Newborn; D012984:Software
D003451:Cryoprotective Agents; D004121:Dimethyl Sulfoxide