Abstract

In the last 10 years induced Pluripotent Stem Cells
(iPSC) have become an essential tool for studying basic biology and for
improving the success of drug discovery such as the acceleration of the
development of cell therapies. Patient-derived iPSC lines provide a powerful
disease-specific and isogenic model which allows scientists to create a more
physiologically relevant disease model as opposed to 2D cell culture. These
models contain key disease driving mutations to achieve mechanistic
understanding and to empower drug screening with increased predictability of
their safety and efficacy.

In this study, we demonstrate the importance of
producing well characterised and quality controlled batches of iPSCs at ECACC, an
official global distributor of iPSC lines from the European Bank of induced
Pluripotent Stem Cells (EBiSC). The collection currently holds over 800 iPSC
lines generated from a wide range of individuals with a variety of monogenic
and polygenic disorders (37 different diseases) and healthy normal donors providing
an invaluable resource for studying genetic contributions to human diseases.

At ECACC, large-scale iPSC banking is performed with
standardization and traceability to provide clarity on how cells have been
banked. Moreover, banked iPSC lines are validated through critical quality
control (QC) tests to confirm their suitability for downstream uses. All EBiSC cell
line batches are subjected to a standard set of quality control assays after cryopreservation.
Viability and post-thaw recovery are confirmed by analysing the growth and by
observing the morphology of the cells and lack of differentiation.  The quality of the cell line is confirmed by the
absence of, microbial contamination (through broth inoculation tests), Mycoplasma
contamination (through Culture Isolation, Hoechst and PCR analysis) and human
pathogenic viruses (through PCR analysis).

Cell line identity is verified by using standard 16
allele Satellite Tandem Repeat (STR) profiling. Genomic integrity is verified
by karyotype analyses carried out on each batch. QC for iPSC bank validation includes
the confirmation of cellular pluripotency by demonstrating the expression, by
flow cytometry analysis, of a panel of intracellular and extracellular markers
of self-renewal and undifferentiation. Functional pluripotency is demonstrated
by direct differentiation of monolayer cultures into all three embryonic germ
layers and then analysing the expression of specific germ layer genes by qPCR.

A high standard of banking and quality control are
critical requirements for high quality iPSC lines to ensure the suitability of
cell lines for streamline applications as models for the study of diseases and screening
therapeutic drugs.