Fig. 5. Disruption and activation of TGF1 signaling has distinct effects on the migration rates of wt and Sdc1-null keratinocytes. (A) wt and Sdc1-null keratinocytes were grown for 3 days, after which keratinocytes were treated with a TGF1 neutralizing antibody overnight and then tracked by time-lapse microscopy the next day. Data show that neutralizing TGF1 reduced wt keratinocyte migration rates by over 50% but inhibited Sdc1-null keratinocyte migration by less than 30% compared with untreated or control IgG treated Sdc1-null keratinocytes. (B) wt and Sdc1-null keratinocytes were grown for 3 days, after which keratinocytes were treated with 0.25 or 2.5 ng/ml TGF1 overnight and then tracked the next day. The migration rates of the Sdc1-null keratinocytes were restored to those of wt keratinocytes after treatment with 0.25 ng/ml TGF1. Further, the Sdc1-null keratinocytes migrated significantly faster than the wt keratinocytes when given 2.5 ng/ml TGF1. Whereas lower concentration of TGF1 stimulated wt keratinocyte migration rates, higher concentration did not. ^*P<0.05; grey line highlights values above untreated wt controls. (C) Localization of LN-332 and 4 integrin in migrating wt and Sdc1-null keratinocytes 24 hours after treatment of keratinocytes with either TGF1-neutralizing antibody (a-d) or with 0.25 ng/ml of TGF1 (e-f). Bar, 5 µm.