Scalable Amounts of Liver and Pancreas Precursor” New Stem Cell Method Developed Increasing the available stem cells by 35 times or more will open the path to more regenerative medicine treatments using stem cells.
Scientists in Canada have overcome a key research hurdle to developing regenerative treatments for diabetes and liver disease with a technique to produce medically useful amounts of endoderm cells from human pluripotent stem cells.
The team stained cells with fluorescent dye and as the cells divided, the dye was shared equally between the divided cells. By measuring the fluorescence of cell populations at a later stage the team were able to work out the frequency of cell division, which allowed them to predict how many cells would be present in a population at any given time.
This technique allowed the team to detect cell inefficiencies and develop a new understanding of the underlying cell biology during the differentiation of PSCs. This allowed the team to increase effective cell production 35 fold.
We present a predictive bioprocess design strategy employing cell- and molecular-level analysis of rate-limiting steps in human pluripotent stem cell (hPSC) expansion and differentiation, and apply it to produce definitive endoderm (DE) progenitors using a scalable directed-differentiation technology. We define a bioprocess optimization parameter (L; targeted cell Loss) and, with quantitative cell division tracking and fate monitoring, identify and overcome key suspension bioprocess bottlenecks. Adapting process operating conditions to pivotal parameters (single cell survival and growth rate) in a cell-line-specific manner enabled adherent-equivalent expansion of hPSCs in feeder- and matrix-free defined-medium suspension culture. Predominantly instructive differentiation mechanisms were found to underlie a subsequent 18-fold expansion, during directed differentiation, to high-purity DE competent for further commitment along pancreatic and hepatic lineages. This study demonstrates that iPSC expansion and differentiation conditions can be prospectively specified to guide the enhanced production of target cells in a scale-free directed differentiation system