Fig. 3
Microclot mechanics under various shear flow conditions. a Overview of the approach for evaluating microclot mechanics under various shear flow conditions. b Time-lapsed phase contrast and fluorescence images of a microclot formed under 167 s−1 shear rate. The number of adhered platelets and microclot contraction gradually increased over a 30-min period, as demonstrated by gradually increased microtissue fluorescence intensity and decreased micropillar distance (L). Measured microclot contractile force (c), fluorescence intensity (d) over the 30-min time period for 3, 33, 167, 500 and 1500 s−1 shear rates. e Phase contrast and fluorescence images of microclots formed after 30 min flow under different shear rates. Increased shear rate leads to increased level of platelet adhesion and microclot contraction, as demonstrated by increased microtissue fluorescence intensity and decreased micropillar distance (L) from shear rate 3 to 1500 s−1. Measured contractile force (f), stiffness (g) and volume (h) of microclots formed at 30 min under different shear rates. Data are presented as mean ± standard deviation for (c), (d). *P < 0.005, **P < 0.05, n > 10, each dot in box plot represents an independent experiment. All box plots with whiskers represent the data distribution based on five number summary (maximum, third quartile, median, first quartile, minimum). Statistical significance was determined by one-way analysis of variance (ANOVA). Scale bar is 200 µm
