Open Access Methodology

Validation of analytical methods in GMP: the disposable Fast Read 102® device, an alternative practical approach for cell counting

Monica Gunetti1*, Sara Castiglia1, Deborah Rustichelli1, Katia Mareschi12, Fiorella Sanavio1, Michela Muraro1, Elena Signorino1, Laura Castello1, Ivana Ferrero12 and Franca Fagioli1

Author Affiliations

1 Paediatric Onco-Haematology, Stem Cell Transplantation and Cellular Therapy Division, Regina Margherita Children’s Hospital, Piazza Polonia 94, Turin, 10126, Italy

2 Department of Paediatrics, University of Turin, Turin, Italy

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Journal of Translational Medicine 2012, 10:112  doi:10.1186/1479-5876-10-112

Published: 31 May 2012

Abstract

Background

The quality and safety of advanced therapy products must be maintained throughout their production and quality control cycle to ensure their final use in patients. We validated the cell count method according to the International Conference on Harmonization of Technical Requirements for Registration of Pharmaceuticals for Human Use and European Pharmacopoeia, considering the tests’ accuracy, precision, repeatability, linearity and range.

Methods

As the cell count is a potency test, we checked accuracy, precision, and linearity, according to ICH Q2. Briefly our experimental approach was first to evaluate the accuracy of Fast Read 102® compared to the Bürker chamber. Once the accuracy of the alternative method was demonstrated, we checked the precision and linearity test only using Fast Read 102®. The data were statistically analyzed by average, standard deviation and coefficient of variation percentages inter and intra operator.

Results

All the tests performed met the established acceptance criteria of a coefficient of variation of less than ten percent. For the cell count, the precision reached by each operator had a coefficient of variation of less than ten percent (total cells) and under five percent (viable cells). The best range of dilution, to obtain a slope line value very similar to 1, was between 1:8 and 1:128.

Conclusions

Our data demonstrated that the Fast Read 102® count method is accurate, precise and ensures the linearity of the results obtained in a range of cell dilution. Under our standard method procedures, this assay may thus be considered a good quality control method for the cell count as a batch release quality control test. Moreover, the Fast Read 102® chamber is a plastic, disposable device that allows a number of samples to be counted in the same chamber. Last but not least, it overcomes the problem of chamber washing after use and so allows a cell count in a clean environment such as that in a Cell Factory. In a good manufacturing practice setting the disposable cell counting devices will allow a single use of the count chamber they can then be thrown away, thus avoiding the waste disposal of vital dye (e.g. Trypan Blue) or lysing solution (e.g. Tuerk solution).

Keywords:
Cell count; Cell factory; Cell therapy; Validation methods; GMP