Fig. 2.

Effect of fibroblast co-culture on labelled U937 cell migration across endothelial cell (EC) monolayers. U937 cells were labelled using ³H-thymidine. Data from a representative of three independent experiments (using three scleroderma (SDF) or normal fibroblast (NDF) strains) are shown. Migration of U937 into the lower culture chamber and binding of U937 to the EC layer were examined in triplicate wells, after 16 h of co-culture. Scleroderma fibroblasts but not NDF increased migration of U937 across the EC monolayer. Activation of the EC layer (EC+) increased U937 cell binding and reduced the number of cells migrating across the monolayer. *P < 0.05 by Student's paired t-test compared with non-fibroblast wells.