Banking stem cells for research and clinical applications

Cell Banking of hiPSCs: A Practical Guide to Cryopreservation and Quality Control in Basic Research

The reproducibility of stem cell research relies on the constant availability of quality-controlled cells. As the quality of human induced pluripotent stem cells (hiPSCs) can deteriorate in the course of a few passages, cell banking is key to achieve consistent results and low batch-to-batch variation. Here, we provide a cost-efficient route to generate master and working cell banks for basic research projects. In addition, we describe minimal protocols for quality assurance including tests for sterility, viability, pluripotency, and genetic integrity. © 2020 The Authors. Basic Protocol 1: Expansion of hiPSCs Basic Protocol 2: Cell banking of hiPSCs Support Protocol 1: Pluripotency assessment by flow cytometry Support Protocol 2: Thawing control: Viability and sterility Support Protocol 3: Potency, viral clearance, and pluripotency: Spontaneous differentiation and qRT-PCR Support Protocol 4: Identity: Short tandem repeat analysis.

Acquisition and Reception of Primary Tissues, Cells, or Other Biological Specimens

The use and banking of biological material for research or clinical application is a well-established practice. The material can be of human or non-human origin. The processes involved in this type of activity, from the sourcing to receipt of materials, require adherence to a set of best practice principles that assure the ethical and legal procurement, traceability, and quality of materials.

The importance of post-thaw subculture for standardizing cellular activity of fresh or cryopreserved mouse embryonic stem cells

Objective

Remarkable difference in cellular activity was found between early and late subpassaged embryonic stem cell (ESCs) lines, which can be created by subtle changes in cell manipulation protocol. This study subsequently examined whether post-thaw subculture of early subpassaged ESC lines could further affect the activity of the ESCs.

Methods

Fresh (as a control treatment) or cryopreserved F1 hybrid (B6CBAF1) early ESC lines (C57BL/6xCBA) of the 4 (P4) or the 19 passage (P19) were subcultured once, twice or six times under the same condition. The post-thaw survival of the ESCs was monitored after the post-treatment subculture and the ability of cell proliferation, reactive oxygen species (ROS) generation, apoptosis and mitochondrial ATP synthesis was subsequently examined.

Results

Regardless of the subculture number, P19 ESCs showed better (p<0.05) doubling time and less ATP production than P4 ESCs and such difference was not influenced by fresh or cryopreservation. The difference between P4 and P19 ESC lines became decreased as the post-treatment subculture was increased and the six times subculture eliminated such difference. Similarly, transient but prominent difference in ROS production and apoptotic cell number was detected between P4 and P19 ESCs only at the 1st subculture after treatment, but no statistical differences between two ESC lines was detected in other observations.

Conclusion

The results of this study suggest that post-thaw subculture of ESCs under the same environment is recommended for standardizing their cellular activity. The activity of cell proliferation ability and ATP synthesis can be used as parameters for quality control of ESCs.

Stem Cell Banking: A Global View

Stem cell banking has been a topic of discussion and debate for more than a decade since the first public services to supply human embryonic stem cells (hESCs) were established in the USA and the UK. This topic has received a recent revival with numerous ambitious programmes announced to deliver large collections of human induced pluripotency cell (hiPSC) lines. This chapter will provide a brief overview charting the development of stem cell banks, their value, and their likely role in the future.

First Proposal of Minimum Information About a Cellular Assay for Regenerative Medicine

: Advances in stem cell research have triggered scores of studies in regenerative medicine in a large number of institutions and companies around the world. However, reproducibility and data exchange among laboratories or cell banks are constrained by the lack of a standardized format for experiments. To enhance information flow in stem cell and derivative cell research, here we propose a minimum information standard to describe cellular assay data to facilitate practical regenerative medicine. Based on the existing Minimum Information About a Cellular Assay, we developed Minimum Information About a Cellular Assay for Regenerative Medicine (MIACARM), which allows for the description of advanced cellular experiments with defined taxonomy of human cell types. By using controlled terms, such as ontologies, MIACARM will provide a platform for cellular assay data exchange among cell banks or registries that have been established at more than 20 sites in the world.

SIGNIFICANCE

Currently, there are more than 20 human cell information storage sites around the world. However, reproducibility and data exchange among different laboratories or cell information providers are usually inadequate or nonexistent because of the lack of a standardized format for experiments. This study, which is the fruit of collaborative work by scientists at stem cell banks and cellular information registries worldwide, including those in the U.S., the U.K., Europe, and Japan, proposes new minimum information guidelines, Minimum Information About a Cellular Assay for Regenerative Medicine (MIACARM), for cellular assay data deposition. MIACARM is intended to promote data exchange and facilitation of practical regenerative medicine.

Regulatory insight into the European human pluripotent stem cell registry

The European pluripotent stem cell registry aims at listing qualified pluripotent stem cell (PSC) lines that are available globally together with relevant information for each cell line. Specific emphasis is being put on documenting ethical procurement of the cells and providing evidence of pluripotency. The report discusses the tasks and challenges for a global PSC registry as an instrument to develop collaboration, to access cells from diverse resources and banks, and to implement standards, and as a means to follow up usage of cells and support adherence to regulatory and scientific standards and transparency for stakeholders.

Standard requirement of a microbiological quality control program for the manufacture of human mesenchymal stem cells for clinical use

The manufacturing of human mesenchymal stem cells (hMSCs) as cell-based products for clinical use should be performed with appropriate controls that ensure its safety and quality. The use of hMSCs in cell therapy has increased considerably in the past few years. In line with this, the assessment and management of contamination risks by microbial agents that could affect the quality of cells and the safety of patients have to be considered. It is necessary to implant a quality control program (QCP) covering the entire procedure of the ex vivo expansion, from the source of cells, starting materials, and reagents, such as intermediate products, to the final cellular medicine. We defined a QCP to detect microbiological contamination during manufacturing of autologous hMSCs for clinical application. The methods used include sterility test, Gram stain, detection of mycoplasma, endotoxin assay, and microbiological monitoring in process according to the European Pharmacopoeia (Ph. Eur.) and each analytical technique was validated in accordance with three different cell cultures. Results showed no microbiological contamination in any phases of the cultures, meeting all the acceptance criteria for sterility test, detection of mycoplasma and endotoxin, and environmental and staff monitoring. Each analytical technique was validated demonstrating the sensitivity, limit of detection, and robustness of the method. The quality and safety of MSCs must be controlled to ensure their final use in patients. The evaluation of the proposed QCP revealed satisfactory results in order to standardize this procedure for clinical use of cells.