Fig. 9. Correlation between cell spreading and substratum coating. (A,B) The area covered by NIH/3T3 cells (A) and B16 cells (B) that have spread was plotted against the actual fibronectin surface for 12 different dot patterns, uncoated and homogeneously coated substrata. Bars represent s.e.m. (C) Three representative cells from patterns with 4% fibronectin coverage (arrow in B). Cell sizes as indicated in the upper right-hand corner were almost equal despite the different fibronectin patterns (actual length and margin to margin distance of dots is given in µm in the upper left corner).