Disintegrin-Integrin Binding for Attachment of Polymer Substrate to the Retina

Pig Models in Retinal Research and Retinal Disease

The pig has been used as a large animal model in biomedical research for many years and its use continues to increase because induced mutations phenocopy several inherited human diseases. In addition, they are continuous breeders, can be propagated by artificial insemination, have large litter sizes (on the order of mice), and can be genetically manipulated using all of the techniques that are currently available in mice. The pioneering work of Petters and colleagues set the stage for the use of the pig as a model of inherited retinal disease. In the last 10 years, the pig has become a model of choice where specific disease-causing mutations that are not phenocopied in rodents need to be studied and therapeutic approaches explored. The pig is not only used for retinal eye disease but also for the study of the cornea and lens. This review attempts to show how broad the use of the pig has become and how it has contributed to the assessment of treatments for eye disease. In the last 10 years, there have been several reviews that included the use of the pig in biomedical research (see body of the review) that included information about retinal disease. None directly discuss the use of the pig as an animal model for retinal diseases, including inherited diseases, where a single genetic mutation has been identified or for multifactorial diseases such as glaucoma and diabetic retinopathy. Although the pig is used to explore diseases of the cornea and lens, this review focuses on how and why the pig, as a large animal model, is useful for research in neural retinal disease and its treatment.

MATRIX-BASED CONTROLLED RELEASE DELIVERY OF ACYCLOVIR FROM POLY-(ETHYLENE CO-VINYL ACETATE) RINGS

Up to 85% of the US adult population carries herpes simplex virus type-1 (HSV-1), with a smaller percentage (22%) infected with HSV-2. Herpesviruses can survive in lytic phase, when the viruses are actively replicating, or in latency, when the virus is functionally dormant in ganglia. Among drugs to treat these infections is acyclovir (ACV). ACV exhibits poor oral bioavailability and a short in vivo half-life; only about 10-15% of ingested drug enters the bloodstream and its half-life is about 3 hours. With those disadvantages and the possibility of poor patient compliance, viral replication may not always be suppressed. To abrogate these shortcomings we propose local distribution via sustained drug release. We present a matrix-based antiherpetic ring, composed of poly(ethylene co-vinyl acetate), that releases ACV directly to the vaginal epithelium. A 30-day in vitro drug release trial showed that approximately 135 +/- 20 μg/day of ACV was consistently released. Rings were nontoxic in cell culture and suppressed primary HSV-1 and HSV-2 replication. We expect these data form the basis for novel interventions in human health, where new prophylactics and therapeutics against genital herpes are truly needed.