Stirred suspension bioreactors maintain naïve pluripotency of human pluripotent stem cells

Abstract

Due to their ability to standardize key physiological parameters, stirred suspension bioreactors can potentially scale the production of quality-controlled pluripotent stem cells (PSCs) for cell therapy application. Because of differences in bioreactor expansion efficiency between mouse (m) and human (h) PSCs, we investigated if conversion of hPSCs, from the conventional “primed” pluripotent state towards the “naïve” state prevalent in mPSCs, could be used to enhance hPSC production. Through transcriptomic enrichment of mechano-sensing signaling, the expression of epigenetic regulators, metabolomics, and cell-surface protein marker analyses, we show that the stirred suspension bioreactor environment helps maintain a naïve-like pluripotent state. Our research corroborates that converting hPSCs towards a naïve state enhances hPSC manufacturing and indicates a potentially important role for the stirred suspension bioreactor’s mechanical environment in maintaining naïve-like pluripotency.

Fluid Shear Stress Promotes Embryonic Stem Cell Pluripotency via Interplay Between β-Catenin and Vinculin in Bioreactor Culture

“…That a higher percentage of mESCs express pluripotency markers in LIF‐free bioreactor compared to static culture suggests that other mechanisms may be operating to promote mechanopluripotency in bioreactor culture (Figure 2E,F). For example, we have recently observed that bioreactors promote expression of the Hippo mechanosensing pathway in naïve human pluripotent stem cells (hPSCs) 43 . Another possible mechanism for promoting mechanopluripotency is the upregulation of Nanog in bioreactor culture.…”

Moving beyond descriptive studies: harnessing metabolomics to elucidate the molecular mechanisms underpinning host-microbiome phenotypes

“…Each of these in vitro organ models provides a mechanism for investigating the molecular underpinnings of host-microbiome interactions. However, all bioreactors and organ models are sensitive to subtle changes in pH, temperature, nutrients, and oxygen levels which can have a dramatic impact the metabolic phenotypes observed in these model systems 27,74,83,95 . Although these platforms provide a controlled environment for testing metabolic hypotheses about interactions of individual species, they generally must be combined with metabolic profiling or in vivo approaches to verify the physiological relevance of the findings (see Table 1 for examples).…”

Design considerations of benchtop fluid flow bioreactors for bio-engineered tissue equivalents in vitro

“…Variation of the stir speed in this manner has been shown to impact the levels of different ECM components secreted by chondrocytes [57] and affect properties such as albumin secretion in HepG2 hepatocellular carcinoma cells [58] . One of the most common uses in tissue engineering is for the expansion of stem cells by maintaining stem cell pluripotency and offering an alternative to methods such as feeder layers [59] , [60] , [61] . This technique can also be used alongside 3D scaffold cultures to allow dynamic fluid flow to support tissue equivalents with a greater degree of structural control [62] , [63] , [64] , [65] .…”