Macrophage mediated mesoscale brain mechanical homeostasis mechanically imaged via optical tweezers and Brillouin microscopy .

Tissues are active materials where epithelial turnover, immune surveillance, and remodeling of stromal cells such as macrophages all regulate form and function. Scattering modalities such as Brillouin microscopy (BM) can non-invasively access mechanical signatures at GHz. However, our traditional understanding of tissue material properties is derived mainly from modalities which probe mechanical properties at different frequencies.

Independent Control of Topography for 3D Patterning of the ECM Microenvironment.

Biomimetic extracellular matrix (ECM) topographies driven by the magnetic-field-directed self-assembly of ECM protein-coated magnetic beads are fabricated. This novel bottom-up method allows us to program isotropic, anisotropic, and diverse hybrid ECM patterns without changing other physicochemical properties of the scaffold material. It is demonstrated that this 3D anisotropic matrix is able to guide the dendritic protrusion of cells.

Mismatch in mechanical and adhesive properties induces pulsating cancer cell migration in epithelial monolayer.

The mechanical and adhesive properties of cancer cells significantly change during tumor progression. Here we assess the functional consequences of mismatched stiffness and adhesive properties between neighboring normal cells on cancer cell migration in an epithelial-like cell monolayer. Using an in vitro coculture system and live-cell imaging, we find that the speed of single, mechanically soft breast carcinoma cells is dramatically enhanced by surrounding stiff nontransformed cells compared with single cells or a monolayer of carcinoma cells.