Collagen turnover induced by cellular connective tissue cytokines of drug induced gingival overgrowth and hereditary gingival fibromatosis (Histological and immunohistochemical comparative study)

Background: Gingival overgrowth (GO) is usually associated with multiple factors including immuno- suppressive agents as cyclosporine (CsA) and Tacrolimus (TAC), and hereditary gingival fibromatosis (HGF).Objective: To compare the expression of TGF-b1, PDGF, TIMP-1 and MMP-9 at the molecular andcellularlevels in patients receiving (CsA or TAC) and patients manifested (HGF), to cast some light on the pathogenic mechanism potentially involved in the collagen (COL) turnover of both conditions. Subjects: and methods: Gingival tissue samples were obtained from patients undergoing therapy with CsA (n ¼ 6), TAC (n ¼ 6), HGF (n ¼ 3) as well as control tissues from systemically healthy control (n ¼ 6).Tissue sections were immune-stained by labeled streptavidin-biotin (DAB) technique, using monoclonal antibodies against TGF-b1, PDGF-b, TIMP-1 and MMP-9