Figure 4
IGF-I and IGF-II stimulated proliferation of skin fibroblasts. Skin fibroblasts grown 4 days in culture were treated with various concentrations of recombinant IGF-I (A) and IGF-II (B) until (3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2 H-tetrazolium, inner salt (MTS) test at day 7. Relative proliferation values were calculated by normalization to cultures treated with diluent (culture medium) only. For IGF-I stimulation, mean EC50 values of 81 ± 30 ng/ml (S1 to S5) and 62 ± 25 ng/ml (K1 to K3) were obtained; PIGF-I (S1-5:K1-3) = 0.246. For IGF-II stimulation, mean EC50 values of 168 ± 96 ng/ml (S1 to S5) and 114 ± 33 ng/ml (K1 to K3) were obtained; PIGF-II (S1-5:K1-3) = 0.261. See Additional files 7 and 8 for tabular data. S, patients with Silver-Russell syndrome; K, control patients.