Fig. 4

a Immunofluorescence of A4573/GFP ES cells grown on a CAM and treated with single IL6 dose as indicated. b Cell coverage across equal-size zones 3, 2 and 1 (right) was estimated by superimposed 3 × 12 square area with values ranging from 0 (no cells present) to 5 (square 100 % filled with cells). See Methods for details. The bar graph (left) illustrates relative mean (± SEM) coverage values for zones 3, 2 and 1 from a total of three independent experiments as a measure of cell motility in response to same-volume applications of PBS, 250 ng and 500 ng rhIL6. Addition of rhIL6 dose-dependently and significantly (* = p < 0.05) increased motility of A4573 ES cells on the surface of the CAM from zone 3 (explant perimeter) to zone 1 (furthest distance)