Figure 4.

PD-L1 knockout significantly decreases MDA-MB-231 cell migration in vitro. Using wound healing assay, scratches were introduced to the adherent monolayer of control and PD-L1 knockout cells. (A,B) Migration distance was determined after 2, 6, and 24 h. (C) Representative pictures of the healing progress of the induced wounds at the indicated time points. Experiments were repeated at least three times. Columns or shapes are means; bars are S.E.M. ** p < 0.01. *** p < 0.001. **** p < 0.0001.