Tumor stiffness has been associated with malignancy and increased risk for metastasis. Extensive research has been done investigating breast cancer cell lines’ responsiveness to surfaces of varying rigidities as well as examining the biophysical properties of breast cancer tumor samples. However, there is a critical gap regarding the relationship between cells’ mechanosensitivity in conjunction to biophysical properties of their extracellular matrix environment. To explore this relationship, we will analyze single-cell mechanosensitivity in comparison to tumor rigidity via shearwave ultrasound elastogrophy (SWE). Given the putative affiliation, we hypothesize that cells expressing invasive mechanosensitivity profiles will correlate with stiffer tumor regions. Using collagen gels containing different cell types, we derived biopsy-sized samples allowing us to optimize single-cell mechanosensitivity analysis. Cells were stained using different dyes corresponding to invasiveness. Subsequently, we analyzed their morphology. Morphological identification within organoid environments would allow for single-cell analysis without the aggression of tissue digestion, though preliminary results suggest high heterogeneity may not allow for confident cell identification solely on morphology. Thus, inquisition into cell viability and integrity was explored by analyzing the effects of tissue digestion with HyQtase on single-cells. Cell count and live-dead stain via flow cytometry allowed for analysis of single-cell viability. Lastly, cell integritymore »
A Model for Studying the Biomechanical Effects of Varying Ratios of Collagen Types I and III on Cardiomyocytes
Purpose
To develop a novel model composed solely of Col I and Col III with the lower and upper limits set to include the ratios of Col I and Col III at 3:1 and 9:1 in which the structural and mechanical behavior of the resident CM can be studied. Further, the progression of fibrosis due to change in ratios of Col I:Col III was tested.
Methods
Collagen gels with varying Col I:Col III ratios to represent a healthy (3:1) and diseased myocardial tissue were prepared by manually casting them in wells. Absorbance assay was performed to confirm the gelation of the gels. Rheometric analysis was performed on each of the collagen gels prepared to determine the varying stiffnesses and rheological parameters of the gels made with varying ratios of Col I:Col III. Second Harmonic Generation (SHG) was performed to observe the 3D characterization of the collagen samples. Scanning Electron microscopy was used for acquiring cross sectional images of the lyophilized collagen gels. AC16 CM (human) cell lines were cultured in the prepared gels to study cell morphology and behavior as a result of the varying collagen ratios. Cellular proliferation was studied by performing a Cell Trace Violet Assay and the applied force on more »
- Publication Date:
- NSF-PAR ID:
- 10276593
- Journal Name:
- Cardiovascular engineering and technology
- Volume:
- 12
- Page Range or eLocation-ID:
- 311-24
- ISSN:
- 1869-4098
- Sponsoring Org:
- National Science Foundation
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