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Microfluidic devices offer well-defined physical environments that are suitable for effective cell seeding and in vitro three-dimensional (3D) cell culture experiments. These platforms have been employed to model in vivo conditions for studying mechanical forces, cell–extracellular matrix (ECM) interactions, and to elucidate transport mechanisms in 3D tissue-like structures, such as tumor and lymph node organoids. Studies have shown that fluid flow behavior in microfluidic slides (µ-slides) directly influences shear stress, which has emerged as a key factor affecting cell proliferation and differentiation. This study investigates fluid flow in the porous channel of a µ-slide using computational fluid dynamics (CFD) techniques to analyze the impact of perfusion flow rate and porous properties on resulting shear stresses. The model of the µ-slide filled with a permeable biomaterial is considered. Porous media fluid flow in the channel is characterized by adding a momentum loss term to the standard Navier–Stokes equations, with a physiological range of permeability values. Numerical simulations are conducted to obtain data and contour plots of the filtration velocity and flow-induced shear stress distributions within the device channel. The filtration flow is subsequently measured by performing protein perfusions into the slide embedded with native human-derived ECM, while the flow rate is controlled using a syringe pump. The relationships between inlet flow rate and shear stress, as well as filtration flow and ECM permeability, are analyzed. The findings provide insights into the impact of shear stress, informing the optimization of perfusion conditions for studying tissues and cells under fluid flow.
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Scale-up of a perfusion-based dendritic cell generation process
Scale up of dendritic cell production is a critical challenge that is infeasible with current static culture systems such as well plates, T-flasks, and bags. We have developed a fully enclosed, sterile cell culture system, called EDEN, that allows for continuous perfusion of fresh differentiation medium into the cell culture cartridge and simultaneous removal of depleted medium. EDEN generated ca. 25 million immature dendritic cells (iDCs) per run with a yield, relative to seeded monocytes, of 20-30%. Immunophenotyping showed that EDEN generated iDCs were phenotypically similar to 6-well plate generated iDCs. Maturation of EDEN iDCs using a standard maturation cocktail was successful with upregulation of CD80/83/86 and downregulation of CD209. Computational fluid dynamics simulations aided the EDEN cartridge design to ensure proper differentiation medium perfusion. These results indicate that EDEN successfully generates clinically relevant numbers of iDCs in a single cell culture cartridge with fewer manual interventions compared to standard culture techniques.
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- Award ID(s):
- 1819306
- PAR ID:
- 10082771
- Date Published:
- Journal Name:
- Cell & gene therapy insights
- Volume:
- 4
- Issue:
- 11
- ISSN:
- 2059-7800
- Page Range / eLocation ID:
- 1117-1130
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.18609/cgti.2018.110
