A micropattern-based assay to study contact inhibition of locomotion and entosis of adherent human and canine cells in vitro.

We present a protocol for using micropatterns to study post-collision locomotion and entosis of human and canine cells in vitro. We describe steps for lentiviral transduction and the preparation of micropatterned slides consisting of narrow matrix-coated stripes separated by cytophobic spacers. We then detail cell seeding, chamber assembly, and live cell analysis.

Loss of contact inhibition of locomotion in the absence of JAM-A promotes entotic cell engulfment.

Entosis is a cell competition process during which tumor cells engulf other tumor cells. It is initiated by metabolic stress or by loss of matrix adhesion, and it provides the winning cell with resources derived from the internalized cell. Using micropatterns as substrates for single cell migration, we find that the depletion of the cell adhesion receptor JAM-A strongly increases the rate of entosis in matrix-adherent cells.

A JAM-A-tetraspanin-αvβ5 integrin complex regulates contact inhibition of locomotion.

Contact inhibition of locomotion (CIL) is a process that regulates cell motility upon collision with other cells. Improper regulation of CIL has been implicated in cancer cell dissemination. Here, we identify the cell adhesion molecule JAM-A as a central regulator of CIL in tumor cells.

Tetraspanins: integrating cell surface receptors to functional microdomains in homeostasis and disease.

Tetraspanins comprise a family of proteins embedded in the membrane through four transmembrane domains. One of the most distinctive features of tetraspanins is their ability to interact with other proteins in the membrane using their extracellular, transmembrane and cytoplasmic domains, allowing them to incorporate several proteins into clusters called tetraspanin-enriched microdomains. The spatial proximity of signaling proteins and their regulators enables a rapid functional cross-talk between these proteins, which is required for a rapid translation of extracellular signals into intracellular signaling cascades.