Extended Data Fig. 7: Saenopy resolves 3D force fields from bright-field image stacks.
From: Dynamic traction force measurements of migrating immune cells in 3D biopolymer matrices
Matrix deformations and forces around a NK92 cell embedded in a 1.2 mg/ml collagen gel (Batch C). Bright-field images are acquired with an ASI RAMM microscope (Applied Scientific Instrumentation, Eugene), CMOS-camera (acA4096-30um, Basler, Ahrensburg),and 20x objective (0.7NA, air, Olympus, Tokyo). The cells are kept at 37∘C and 5% CO2 in a stage incubator (Tokai HIT, Fujinomiya). Matrix deformations (left) are calculated from bright-field image stacks (120 × 120 × 120 μm, with a voxel-size of 0.15 × 0.15 × 2 μm, dt = 30 s) during a contractile phase (SI Video 13, at t = 2 min). Cell forces (right) and corresponding matrix deformations (middle) are reconstructed using a regularization parameter of 1011. Maximum intensity projected image stacks are shown below the 3D cubes.
