Grants We Funded

Abstract
Project Summary: Chronic wounds affect 6.7 millions of Americans annually at a high cost to society. Important factors that limit wound healing are bacterial colonization, infection, and biofilm formation. Biofilms are coordinated networks of multiple bacteria that are challenging to treat. Within a biofilm, bacteria work together to help each other survive, grow, and defend against antibiotic treatment. The normal course of treatment for these biofilm challenged chronic wounds includes surgery, frequent dressing changes, and long courses of antibiotic treatment. The long and repeated rounds of antibiotics can lead to antibiotic resistant bacteria making treatment even more difficult. Additionally, these “superbugs” can spread creating dangerous infections with few therapeutic options. Patients deserve better care for these challenging wounds. This project will examine a collagen-rich hydrogel (cHG) to serve as both a wound dressing and antibacterial treatment for chronic wounds. We hypothesize that cHG, previously shown to accelerate wound healing in the absence of infection, can be used as a carrier for local antibiotic delivery to treat biofilm challenged wounds and lead to faster wound healing without the risks of systemic antibiotic treatment. We will examine the rate of antibiotic elution of three effective antibiotics and test the ability of the cHG with antibiotics (cHG + abx) to eliminate bacteria and halt biofilm formation. We will test the safety of cHG + abx against human cells. Next we will evaluate the rate of wound healing in biofilm challenged wounds using cHG + abx versus standard wound care. Lastly, we will mimic the complex bacterial signature of human chronic wounds and test the ability of cHG + abx to treat multiple bacteria simultaneously by delivering multiple antibiotics to the wound topically. Through this project, we will demonstrate the effectiveness of cHG + abx for chronic wound care. Ultimately, cHG could be used at the bedside as personalized treatment for each patient suffering from a chronic wound. The bacteria within the wound would be identified and the appropriate antibiotic therapy determined. Custom cHG + abx would be mixed at the bedside and applied to both accelerate wound healing and eliminate bacteria within the wound. This easy wound care could be performed every other day thereby, simplifying and improving chronic wound care for millions of Americans. Impact Statement: Collagen-rich hydrogel is a unique topical treatment for chronic wounds. This hydrogel can be augmented with antibiotics to accelerate wound healing and defend against bacteria that delay wound closure. By delivering antibiotics locally at the wound site, higher and more effective dosing of antibiotics can be used without the side effects of normal antibiotic treatment. Additionally, targeted antibiotic therapy customized for each patient will limit the need for repeated courses of broad-spectrum antibiotics that lead to multidrug resistant bacteria, also known as “superbugs”. The Centers for Disease Control have identified antibiotic resistance as a major threat to human health. Collagen hydrogel enriched with antibiotics is great way to fight back against the emergence of superbugs.

Biography
In 2015, Dr. Fox joined the Plastic Surgery faculty at Stanford University. She sees patients at the Veterans Affairs-Palo Alto campus, and Lucille Packard Children’s Hospital as well. In addition to clinical responsibilities, she has a basic science lab examining the application of tissue engineering to wound care and upper extremity surgery. Her work has focused on collagen based scaffolds for treating tendon and ligament injuries. Most recently she has begun applying these scaffolds to wound healing models. Dr. Fox received a combined MD/PhD (Microbiology) from Virginia Commonwealth University in 2008. Her PhD research was related to antibiotic resistance in bacteria. She developed a number of critical bench skills during this time, including microscopy fixation and staining techniques, as well as quantitative RT-PCR and protein analysis. In summer 2008, Dr. Fox commenced a residency in Plastic Surgery at Stanford University. Following residency, she completed a fellowship in Hand Surgery at Mayo Clinic. During these training periods, she worked on multiple clinical research projects with the goal of using data to move the fields of plastic and hand surgery forward. These projects allowed her to continue thinking critically about the problems faced by patients and surgeons and how to improve the care of these patients. While at Stanford and Mayo Clinic, she gained the critical surgical knowledge and skills to allow her to be a translational researcher.