TY - JOUR
T1 - Current practices and prospects for standardization of the hematopoietic colony-forming unit assay
T2 - A report by the cellular therapy team of the Biomedical Excellence for Safer Transfusion (BEST) Collaborative
AU - Pamphilon, Derwood
AU - Selogie, Eileen
AU - McKenna, David H
AU - Cancelas-Peres, Jose A.
AU - Szczepiorkowski, Zbigniew M.
AU - Sacher, Ron
AU - McMannis, John
AU - Eichler, Hermann
AU - Garritsen, Henk
AU - Takanashi, Minoko
AU - Van De Watering, Leo
AU - Stroncek, David
AU - Reems, Jo Anna
N1 - Funding Information:
We would like to thank members of the Biomedical Excellence for Safer Transfusion (BEST) Collaborative cellular therapy team. This work was supported in part by the BEST Collaborative and the Puget Sound Blood Center.
PY - 2013/3
Y1 - 2013/3
N2 - Background aims. Wide acceptance of the colony-forming unit (CFU) assay as a reliable potency test for stem cell products is hindered by poor inter-laboratory reproducibility. The goal of this study was to ascertain current laboratory practices for performing the CFU assay with an eye towards identifying practices that could be standardized to improve overall reproducibility. Methods. A survey to evaluate current laboratory practices for performing CFU assays was designed and internationally distributed. Results. There were 105 respondents to the survey, of whom 68% performed CFU assays. Most survey recipients specified that an automated rather than a manual cell count was performed on pre-diluted aliquots of stem cell products. Viability testing methods employed various stains, and when multiple sites used the same viability stain, the methods differed. Cell phenotype used to prepare working cell suspensions for inoculating the CFU assay differed among sites. Most respondents scored CFU assays at 14e16 days of incubation, but culture plates were read with various microscopes. Of 57 respondents, 42% had not performed a validation study or established assay linearity. Only 63% of laboratories had criteria for determining if a plate was overgrown with colonies. Conclusions. Survey results revealed inconsistent inter-laboratory practices for performing the CFU assay. The relatively low number of centers with validated CFU assays raises concerns about assay accuracy and emphasizes a need to establish central standards. The survey results shed light on numerous steps of the methodology that could be targeted for standardization across laboratories.
AB - Background aims. Wide acceptance of the colony-forming unit (CFU) assay as a reliable potency test for stem cell products is hindered by poor inter-laboratory reproducibility. The goal of this study was to ascertain current laboratory practices for performing the CFU assay with an eye towards identifying practices that could be standardized to improve overall reproducibility. Methods. A survey to evaluate current laboratory practices for performing CFU assays was designed and internationally distributed. Results. There were 105 respondents to the survey, of whom 68% performed CFU assays. Most survey recipients specified that an automated rather than a manual cell count was performed on pre-diluted aliquots of stem cell products. Viability testing methods employed various stains, and when multiple sites used the same viability stain, the methods differed. Cell phenotype used to prepare working cell suspensions for inoculating the CFU assay differed among sites. Most respondents scored CFU assays at 14e16 days of incubation, but culture plates were read with various microscopes. Of 57 respondents, 42% had not performed a validation study or established assay linearity. Only 63% of laboratories had criteria for determining if a plate was overgrown with colonies. Conclusions. Survey results revealed inconsistent inter-laboratory practices for performing the CFU assay. The relatively low number of centers with validated CFU assays raises concerns about assay accuracy and emphasizes a need to establish central standards. The survey results shed light on numerous steps of the methodology that could be targeted for standardization across laboratories.
KW - Colony-forming-units
KW - Hematopoietic
KW - Hematopoietic progenitor cells
KW - Potency test
UR - http://www.scopus.com/inward/record.url?scp=84875448353&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84875448353&partnerID=8YFLogxK
U2 - 10.1016/j.jcyt.2012.11.013
DO - 10.1016/j.jcyt.2012.11.013
M3 - Article
C2 - 23579058
AN - SCOPUS:84875448353
VL - 15
SP - 255
EP - 262
JO - Cytotherapy
JF - Cytotherapy
SN - 1465-3249
IS - 3
ER -