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bioRxiv · 10.1101/2024.10.30.621138

A simple, cost-effective microfluidic device using a 3D cross-flow T-junction for producing decellularized extracellular matrix-derived microcarriers

Kamar, F.·Gillis, C. J.·Bischoff, G.·Ali, A.·de Bruyn, J. R.·Flynn, L. E.·Poepping, T. L.
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Abstract

Cell therapies using human mesenchymal stromal cells (MSCs) are promising for a wide variety of clinical applications. However, broad-scale clinical translation is limited by conventional culture methods for MSC expansion within 2D tissue-culture flasks. MSC expansion on ECM-derived microcarriers within stirred bioreactor systems offers a promising approach to support MSC growth. Previously, our team established methods for fabricating ECM-derived microcarriers from a variety of decellularized tissue sources using electrospraying techniques. However, these microcarriers are relatively large and have a broad size distribution, which may limit their utility. Smaller and more uniform microcarriers may be favorable for MSC growth within bioreactors and have greater potential to serve as a minimally invasive injectable cell delivery platform. To address these limitations, the current project focused on the development of a new microfluidic-based approach enabling both uniform and small microcarrier production. Using a novel, modified 3D T-junction design, we successfully generated microcarriers using human decellularized adipose tissue (DAT) as the ECM source. Our new cost-effective device produced microbeads that were small and monodisperse, at a range of flow rate combinations and with high production rates. Photo-crosslinking using rose bengal allowed for the generation of microcarriers that were stable following rehydration, with a mean diameter of 196 {+/-} 47 {micro}m. Following methods optimization and microcarrier characterization, in vitro studies confirmed that the new microcarriers supported human adipose-derived stromal cell (hASC) attachment and growth, as well as ECM production, across 14 days within spinner flask bioreactors. Overall, this study demonstrates the feasibility of using our novel, cost-effective, and reusable microfluidics device to generate cell-supportive microcarriers comprised exclusively of ECM in a size range that could be injected via a small gauge needle and were stable in long-term culture.

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Kamar, F., Gillis, C. J., Bischoff, G., Ali, A., de Bruyn, J. R., Flynn, L. E., Poepping, T. L.. 2024-11-03. A simple, cost-effective microfluidic device using a 3D cross-flow T-junction for producing decellularized extracellular matrix-derived microcarriers. https://doi.org/10.1101/2024.10.30.621138

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