Mass cultivation of stem cells

Present situation worldwide and in Switzerland

With advances in organ and tissue transplants, the shortage of organs and a rising demand for donors have become major hurdles. Scientific research has therefore begun to develop alternatives and suggested therapies based on human stem cells (HSCs). It is now generally acknowledged that the use of HSCs shows promise for biotechnological, pharmaceutical and medical applications such as cell therapy, tissue engineering or regenerative medicine. HSCs are able to self-renew and differentiate into specialised cell types. They are defined by their origin and their potency: pluripotent stem cells (PSCs) have the capacity for unlimited self-renewal and can differentiate into any of the body’s more than 200 cell types. There are two sources of PSCs: embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs). There are also multipotent stem cells, isolated from sources such as mesenchymal stem cells, and which unlike PSCs can differentiate only into a limited amount of cell types. Given the wide range of R&D and industry applications, the demand for stem cells is rising steadily. Many efforts are being undertaken to cultivate stem cells on a large scale and to differentiate them into cell types of interest in an efficient and homogenous manner. Most laboratories multiply stem cells on level surfaces in two-dimensional cultures, so-called monolayers. The production of large amount of cells is carried out by multiplying culture dishes: a highly time-consuming, expensive and labour-intensive method.

Implications for Switzerland

The challenge for stem cell producers is to develop lawful and cost-effective large-scale production processes. Such processes require automated, controlled and scalable production systems. The current trend is moving away from two-dimensional cultures toward suspension cultures (3D cultures) that grow in single-use bioreactors under controlled conditions. Such systems are a prerequisite for affordable stem cell-based therapies and require collaboration between biomedical researchers and engineers. The global market for stem cells is growing and should reach 5–10 billion USD by 2022. The large-scale production of stem cells is still in its infancy. In Switzerland, public and private research institutions are training leading scientists and engineers. Switzerland is therefore well positioned to play a significant role in developing relevant production processes using bioreactors.