Table 3.

Responses of MDCK epithelial cells and NIH 3T3 fibroblasts to head or tail contact

Cell line	Retreating from an approaching neighbor, %	Following a retreating neighbor, %
MDCK epithelial cells	83.6 ± 3.7 (n = 91)***	75.7 ± 5.0 (n = 74)***
NIH 3T3 fibroblasts	86.3 ± 4.9 (n = 51)***	70.0 ± 7.3 (n = 40)*

The majority of cells stalled at an X intersection initiated migration within 1.5 h upon contact with a migrating cell, either away from an approaching cell or toward a retreating cell. Numbers indicate the percentage of cells stalled at an X intersection that initiated directional migration upon contact with a migrating cell. Significance was determined using a one-sample binomial test against the null hypothesis of equal probability of entering any branch. *P < 0.05, ***P < 0.0005.