Figure 2.

Dysregulation of force production from septic neutrophils occurs primarily in-plane. Traction force microscopy of neutrophils from a healthy donor (n = 293) or a septic donor (n = 24) on 1.5 kPa polyacrylamide gels wherein the in-plane traction component ($\Vert$) along the surface of the substrate is separated from the out-of-plane traction component ($\perp$) going into/out-of the surface of the substrate, computing mean (and SEM) of (a) in-plane total forces (${\mathbf{F}}_{\Vert }$) and out-of-plane total forces (${\mathbf{F}}_{\perp }$), (b) in-plane RMS tractions ($T_{\mathit{RMS}}\Vert$) & out-of-plane RMS tractions ($T_{\mathit{RMS}}\perp$), and (c) in-plane traction maxima ($T_{\mathit{Max}}\Vert$) and out-of-plane traction maxima ($T_{\mathit{Max}}\perp$). Displacements were computed in Matlab by T-PT, and in-plane (d) and out-of-plane (e) displacement heatmaps were generated for two representative cells at 30 min; tractions were computed using the finite element method in Abaqus. Scale bars are 10 μm, and the white contours represents the boundary of the cell edge. *p < 0.05, ****p < 0.0001 (unpaired Student’s t-test).