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Abstract Multicellular spheroids have shown great promise in 3D biology. Many techniques exist to form spheroids, but how cells take mechanical advantage of native fibrous extracellular matrix (ECM) to form spheroids remains unknown. Here, we identify the role of fiber diameter, architecture, and cell contractility on spheroids’ spontaneous formation and growth in ECM-mimicking fiber networks. We show that matrix deformability revealed through force measurements on aligned fiber networks promotes spheroid formation independent of fiber diameter. At the same time, larger-diameter crosshatched networks of low deformability abrogate spheroid formation. Thus, designing fiber networks of varying diameters and architectures allows spatial patterning of spheroids and monolayers simultaneously. Forces quantified during spheroid formation revealed the contractile role of Rho-associated protein kinase in spheroid formation and maintenance. Interestingly, we observed spheroid–spheroid and multiple spheroid mergers initiated by cell exchanges to form cellular bridges connecting the two spheroids. Unexpectedly, we found large pericyte spheroids contract rhythmically. Transcriptomic analysis revealed striking changes in cell–cell, cell–matrix, and mechanosensing gene expression profiles concordant with spheroid assembly on fiber networks. Overall, we ascertained that contractility and network deformability work together to spontaneously form and pattern 3D spheroids, potentially connecting in vivo matrix biology with developmental, disease, and regenerative biology.
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Assessing Cellular Metabolism Using 2-Photon Imaging And Cancer Spheroids
Introduction: Spheroids show great promise in being a better model for testing treatments for cancer in vitro when compared to monolayer cells. Single photon imaging of spheroids is limited by depth. Due to this reason, two photon imaging is necessary to obtain a full image of the spheroid. We developed a software that can evaluate the cellular metabolism of a spheroid by calculating the Redox Index (NADH divided by FAD). We tried to validate this software by treating the spheroids with an ATP antagonist.
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- Award ID(s):
- 1757885
- PAR ID:
- 10138563
- Date Published:
- Journal Name:
- 2019 BMES Conference Proceedings - REU Abstract Accepted Poster
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Accepted Manuscript1.0
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