Pro-angiogenic character of endothelial cells and gingival fibroblasts cocultures in perfused degradable polyurethane scaffolds.

Gingival atrophy manifests as exposure of the tooth root surface because of recession of the gingiva, a condition that affects >20% of adults and leads to increased root sensitivity and ultimately, tooth loss. Tissue engineering approaches that employ novel synthetic polymeric scaffolds are being considered for rebuilding the gingival lamina propria lost in the atrophic process. Specifically, polyurethane hydrogels (degradable/polar/hydrophobic/ionic polyurethane [D-PHI]) can enhance the proliferation of human gingival fibroblasts (HGFs) and collagen production in a perfusion system.

Establishing a gingival fibroblast phenotype in a perfused degradable polyurethane scaffold: mediation by TGF-β1, FGF-2, β1-integrin, and focal adhesion kinase.

Medium perfusion has been shown to enhance cell proliferation and matrix protein production. In more recent work, under perfusion, a degradable/polar/hydrophobic/ionic polyurethane (D-PHI) scaffold was shown to enhance growth and production of collagen by human gingival fibroblasts (HGFs). However, the nature of the HGFs cultured in the perfused D-PHI scaffolds, and the mechanisms by which medium perfusion activates these cells to facilitate proliferation and collagen production are not defined.

Biomaterials in co-culture systems: towards optimizing tissue integration and cell signaling within scaffolds.

Most natural tissues consist of multi-cellular systems made up of two or more cell types. However, some of these tissues may not regenerate themselves following tissue injury or disease without some form of intervention, such as from the use of tissue engineered constructs. Recent studies have increasingly used co-cultures in tissue engineering applications as these systems better model the natural tissues, both physically and biologically.

Perfused culture of gingival fibroblasts in a degradable/polar/hydrophobic/ionic polyurethane (D-PHI) scaffold leads to enhanced proliferation and metabolic activity.

Periodontal diseases cause the breakdown of the tooth-supporting gingival tissue. In treatments aimed at gingival tissue regeneration, tissue engineering is preferred over the common treatments such as scaling. Perfused (dynamic) culture has been shown to increase cell growth in tissue-engineered scaffolds.

Immuno-atomic force microscopy characterization of adsorbed fibronectin.

The fibronectin (Fn) binding conformation on mica and ultraflat poly(D,L-lactide-co-glycolide) (UPLGA) was characterized using atomic force microscopy (AFM). AFM topographic images showed that Fn was in an extended form on mica and in a compact structure on UPLGA. With immuno-AFM, an antibody (Ab(hep)) was used to characterize the Fn binding conformation.