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Abstract Cell motility is a critical aspect of several processes, such as wound healing and immunity; however, it is dysregulated in cancer. Current limitations of imaging tools make it difficult to study cell migrationin vivo. To overcome this, and to identify drivers from the microenvironment that regulate cell migration, bioengineers have developed 2D (two‐dimensional) and 3D (three‐dimensional) tissue model systems in which to study cell motilityin vitro, with the aim of mimicking elements of the environments in which cells movein vivo. However, there has been no systematic study to explicitly relate and compare cell motility measurements between these geometries or systems. Here, we provide such analysis on our own data, as well as across data in existing literature to understand whether, and which, metrics are conserved across systems. To our surprise, only one metric of cell movement on 2D surfaces significantly and positively correlates with cell migration in 3D environments (percent migrating cells), and cell invasion in 3D has a weak, negative correlation with glioblastoma invasionin vivo. Finally, to compare across complex model systems,in vivodata, and data from different labs, we suggest that groups report an effect size, a statistical tool that is most translatable across experiments and labs, when conducting experiments that affect cellular motility.
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Tracking the invasion of breast cancer cells in paper-based 3D cultures by OCT motility analysis
3D paper-based cultures (PBCs) are easy-to-use and provide a biologically representative microenvironment. By stacking a sheet of cell-laden paper below sheets containing cell-free hydrogel, we form an assay capable of segmenting cells by the distance they invaded from the original cell-seeded layer. These invasion assays are limited to end-point analyses with fluorescence-based readouts due to the highly scattering nature of the paper scaffolds. Here we demonstrate that optical coherence tomography (OCT) can distinguish living cells from the surrounding extracellular matrix (ECM) or paper fibers based upon their intracellular motility amplitude (M).Mis computed from fluctuation statistics of the sample, rejects shot noise, and is invariant to OCT signal attenuation. Using OCT motility analysis, we tracked the invasion of breast cancer cells over a 3-day period in 4-layer PBCs (160–300 µm thick)in situ. The cell population distributions determined with OCT are highly correlated with those obtained by fluorescence imaging, with an intraclass correlation coefficient (ICC) of 0.903. The ability of OCT motility analysis to visualize live cells and quantify cell distributions in PBC assaysin situand longitudinally provides a novel means for understanding how chemical gradients within the tumor microenvironment affect cellular invasion.
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- Award ID(s):
- 1803830
- PAR ID:
- 10155277
- Publisher / Repository:
- Optical Society of America
- Date Published:
- Journal Name:
- Biomedical Optics Express
- Volume:
- 11
- Issue:
- 6
- ISSN:
- 2156-7085
- Format(s):
- Medium: X Size: Article No. 3181
- Size(s):
- Article No. 3181
- Sponsoring Org:
- National Science Foundation
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