Figure 4. Effects of IL-1 and type I collagen on the expression of MT1-MMP mRNA and protein in odontogenic keratocyst fibroblasts. Agarose gel of the PCR products of MT1-MMP and ß-actin (A) and Western immunoblotting for MT1-MMP (B). Odontogenic keratocyst fibroblasts were incubated on plastic plates (lanes 1 and 2) or 30 µg/cm² type I collagen-coated dishes (lanes 3 and 4) in the absence (lanes 1 and 3) or presence (lanes 2 and 4) of 1 nM rhIL-1 for 48 hrs at 37°C. (A) Total cellular RNA was extracted, and PCR amplification was performed at 35 cycles. The PCR products of MT1-MMP and ß-actin were resolved by electrophoresis on 1.8% agarose gel. (B) The fibroblasts were lysed in SDS sample buffer, and the aliquots of cell lysates were subjected to Western immunoblotting for MT1-MMP as described under "MATERIALS & METHODS". Similar results were seen in six independent experiments.