The arthritogenic SF clone B2 has a higher proliferation rate and exhibits increased migration to fibronectin. (a) DNA synthesis/proliferation assay as described in Materials and methods in the presence or absence of 10% FBS. Values represent [3H]thymidine incorporation (× 103). Mean averages of triplicates. Representative experiment out of three. t-test P values were always less than 0.01. (b) Migration assays as described in Materials and methods. Migration shown was for 2 hours; similar results were found for 4 hours. Mean averages of triplicates with mean background (adhesion to BSA) values subtracted. Representative experiment out of three. t-test P values were always less than 0.05. (c) Assay of wound healing, as described in Materials and methods. Pictures were taken at 0 and 48 hours after the wound. BSA = bovine serum albumin; FBS = fetal bovine serum; hTNF = human tumor necrosis factor; SF = synovial fibroblast; TAg = large tumor antigen; wt = wild-type.