Effect of c-Kit activation on integrin-directed migration in mast cells. Activation of c-Kit modulates integrin-directed (haptotactic) migration in mast cells. Migration assays were performed with the use of mast cells and FN (H296, which contains binding site for α4β1; or CH271, which contains binding site for α5β1) in the presence or absence of increasing SCF concentrations as described in “Materials and methods.” Cell migration is expressed as a migration index and calculated as the fold increase over the negative control (BSA-coated wells). Cell migration on BSA was less than 0.001% of the total cell population. Shown are the means ± standard errors of the means (SEMs) of 40 different fields from 2 independent experiments performed in duplicate. *P < .05 for α4β1 or α5β1 in the presence of SCF (all concentrations) versus α4β1 or α5β1 in the absence of SCF (all concentrations).
