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Abstract It is increasingly recognized that brain microvascular endothelial cells (BMECs), the principal component of the blood‐brain barrier (BBB), are highly sensitive to soluble cues from both the bloodstream and the brain. This concept extends in vitro, where the extracellular milieu can also influence BBB properties in cultured cells. However, the extent to which baseline culture conditions can affect BBB properties in vitro remains unclear, which has implications for model variability and reproducibility, as well as downstream assessments of molecular transport and disease phenotypes. Here, we explore this concept by examining BBB properties within human‐induced pluripotent stem cell (iPSC)‐derived BMEC‐like cells cultured under serum‐free conditions in DMEM/F12 and Neurobasal media, which have fully defined compositions. We demonstrate notable differences in both passive and active BBB properties as a function of basal media composition. Further, RNA sequencing and phosphoproteome analyses revealed alterations to various signaling pathways in response to basal media differences. Overall, our results demonstrate that baseline culture conditions can have a profound influence on the performance of in vitro BBB models, and these effects should be considered when designing experiments that utilize such models for basic research and preclinical assays. image
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This content will become publicly available on January 27, 2026
Modular cone-and-plate device for mechanofluidic assays in Transwell inserts
In this work, we present a cost effective and open-source modular cone-and-plate (MoCAP) device that incorporates shear stress in the popular Transwell®insert system. This system acts as a lid that incorporates flow into 24-well Transwell®inserts while preserving the ability to conduct molecular profiling assays. Moreover, the MoCAP device can be rapidly reconfigured to test multiple shear stress profiles within a single device. To demonstrate the utility of the MoCAP, we conducted select assays on several different brain microvascular endothelial cell (BMEC) lines that comprise models of the blood-brain barrier (BBB), since shear stress can play an important role in BBB function. Our results characterize how shear stress modulates passive barrier function and GLUT1 expression across the different BMEC lines. Overall, we anticipate this low cost mechanofluidic device will be useful to the mechanobiology community.
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- Award ID(s):
- 2244050
- PAR ID:
- 10579232
- Publisher / Repository:
- Frontiers
- Date Published:
- Journal Name:
- Frontiers in Bioengineering and Biotechnology
- Volume:
- 13
- ISSN:
- 2296-4185
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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