Figure 2.

Quantification of the peak indentation modulus of different ECM compositions. (A) Collagen gels in cylindrical molds were loaded into a mechanical load frame and subjected to incremental indentation–relaxation steps at a strain rate $\left(\dot{\epsilon }\right)$ of 10% of the gel thickness (t_gel). (B) The load applied to the indenter was recorded and plotted over time to obtain the peak indentation loads. (C) The peak indentation loads were converted to peak indentation stresses and plotted against the corresponding indentation strain (starting from 20%) to compute the peak indentation modulus (E_ind). (D) Peak indentation modulus measurements. hrTGII did not alter the peak indentation modulus compared to control conditions. Addition of HA significantly increased the peak indentation loading for both 3 and 6 mg/mL collagen gels.