Figure 6: MMP-1 and TIMP-1 expression. (a) Representative slot blot showing MMP-1 levels in serum-free cell culture supernatants of fibroblasts from healthy and overgrown gingivae. Immunoreactive bands were quantified by densitometric scanning as described in Materials and Methods. (b) Bar graphs showing MMP-1 protein levels analyzed by slot blot. Data are expressed as densitometric units and are for samples run in duplicate. (c) Bar graphs showing TIMP-1 gene expression after normalization on GAPDH mRNA levels. Data are expressed as for samples run in triplicate. and .