Figure 3
From: Engineering aligned human cardiac muscle using developmentally inspired fibronectin micropatterns
Analysis of sub-cellular differences in embryonic chick cardiomyocyte adhesion and alignment to the biomimetic and 20 × 20 fibronectin micropatterns as a function of cell density. (A) At low density, chick cardiomyocytes adhere and align directly to the 20 × 20 fibronectin lines due to spatial confinement and the inability to bridge across lines. (B) At high density, chick cardiomyocytes are able to bridge the 20 × 20 lines to form a confluent monolayer that is still aligned. (C) At low density, chick cardiomyocytes adhere to the various features in the biomimetic pattern and are not well aligned. (D) At high density, chick cardiomyocytes adhere to the entire surface of the biomimetic pattern and are well aligned. (E) Heat maps of cell substrate coverage, showing the normalized occurrence of cardiomyocytes adhering to the biomimetic and 20 × 20 micropatterns at both low and high cell densities. (F) Histogram of substrate coverage for chick cardiomyocytes on the biomimetic pattern at low and high densities, indicating the normalized occurrence of a cell adhering to the biomimetic pattern, binned in to 1 µm2 regions. (G) Heat maps of cell OOP, showing regional variation in cardiomyocyte alignment on the biomimetic and 20 × 20 micropatterns at both low and high cell densities. (H) Histogram of OOP for chick cardiomyocytes on the biomimetic pattern at low and high densities. Scale bars are 20 µm. Heat maps and orientation plots were generated with a custom MATLAB code (MATLAB 2017a, https://www.mathworks.com/products/new_products/release2017a.html).
