This project investigates the potential of functionalizing poly methyl methcrylate (PMMA) with poly (ethylene glycol) (PEG) to inhibit epithelial cell in growth and inflammatory reactions to the prospective intraocular lens. PMMA displays strong posterior attachment, but some in-growth. Trace functionalization with PEG will further inhibit undesired biological responses without disturbing the strong posterior attachment of PMMA. A suitable in vitro experimental model will measure these responses at low cost to determine if in vivo pursuit is worthwhile. This model uses the human corneal epithelial cell line HCE- I as an epithelial cell model. HCE-1 cells will be cultured, passaged and placed onto the different biomaterials. Adherent cells will be visualized and counted using inverted microscopy and computerized image analysis. Adhesion will be based on the spread area/cell and fraction of biomaterial surface occupied by adherent cells. HCE-1 cells will be incubated on bare and protein-preadsorbed PEG-functionalized PMMA to reveal the role of proteins in promoting cell adhesion. The proteins selected are human fibronectin, an adhesive RGD protein, and serum albumin, a nonadhesive protein. Human fibronectin will be isolated from citrated whole human blood and characterized, including its biological activity. Protein adsorption will be quantified radiolabelling proteins with 125, using the chloramine-T method. This project will synthesize and characterize PMMA pendantly functionalized with poly(ethylene glycol), including ESCA and contact angle goniometry. Goniometry of protein-preadsorbed polymers will be endeavored. Macrophage adhesion will be quantified to appraise possible inflammatory reactions that these biomaterials can elicit. Macrophages will isolated from whole human blood by centrifugation on a Ficoll-Hypaque gradient. Macrophage chemotaxis and phagocytosis will be assessed. The morphology of adherent macrophages and HCE- I cells will also be examined with scanning electron microscopy.
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Shibeshi, Shewaferaw S; Collins, William E (2005) The Rheology of Blood Flow in a Branched Arterial System. Appl Rheol 15:398-405 |
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