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Grants We Funded

Grant Applicants for 2020 requested more than $4.1 million. The PSF Study Section Subcommittees of Basic and Translational Research and Clinical Research Evaluated 111 applications on the following topics:

The PSF awarded Research Grants totaling more than $860,000 to support 24 plastic surgery research proposals.

The American Society of Plastic Surgeons/PSF leadership is committed to continuing to provide high levels of investigator-initiated research support to ensure that plastic surgeons have the needed research resources to be pioneers and innovators in advancing the practice of medicine.

Research Abstracts

Search The PSF database to have easy access to full-text grant abstracts from past PSF-funded research projects 2003 to present. All abstracts are the work of the Principal Investigators and were retrieved from their PSF grant applications. Several different filters may be applied to locate abstracts specific to a particular focus area or PSF funding mechanism.

Investigation of Muscle Reinnervation and Functional Recovery

Principal Investigator
Philip Johnson PhD


Washington University

Funding Mechanism

Focus Area

Peripheral nerve injuries are estimated to occur in 5% of patients with traumatic injury presenting to level 1 trauma centers and have a limited ability for natural recovery. The ideal surgical repair of a peripheral nerve injury is the end- to-end coaptation of the proximal and distal ends to produce a tension free repair. Following peripheral nerve injury and reconstruction, a major factor contributing to limited functional recovery is the inability of regenerating motor neurons to accurately find their denervated muscle targets. We have shown that constitutive overexpression of glial derived neurotrophic factor (GDNF) in skeletal muscle (i.e. the periphery) increases peripheral nerve regeneration and overexpression of GDNF in the central nervous system actually reduces regeneration. We have also demonstrated that controlled release of GDNF at the site of injury can enhance functional recovery. Despite these observations, others have demonstrated that GNDF does not increase the number of regenerating motor neurons immediately after nerve injury. Instead it is proposed that GDNF only stimulates increased axonal sprouting. Given these observations, we hypothesize that GDNF enhances functional recovery in rodent models of peripheral nerve injury by increasing the efficiency with which regenerating axons reinnervate motor end plates. To evaluate this hypothesis we will evaluate the relationship between muscle reinnervation efficiency and function recovery in multiple clinically relevant nerve injury paradigms (Aim 1). We will then use this information to evaluate the ability of increased GDNF levels in the denervated muscle to augment reinnervation efficiency and functional recovery following peripheral nerve injury (Aim2). The completion of this proposal will lead to the study of new clinically relevant treatments that target the denervated muscle to enhance functional recovery following peripheral nerve injury.

Philip Johnson received his Ph.D. in Biomedical Engineering from Washington University in St. Louis. His research expertise is in cell transplant therapies, drug delivery techniques, tissue engineering, and evaluation of implantable biomaterials (in vivo/ in vitro). Current research interests include utilizing neural tissue engineering techniques to enhance peripheral nerve regeneration. Specifically, he is interested in the mechanism of FK-506 mediated enhancement of nerve regeneration through direct action on regenerating neurons and through stimulation of the innate wound healing response. His lab is also interested in the augmentation of decellularized tissues through chemical conjugation to enhance their roles as mediums for cell transplantation and scaffolds for tissue synthesis. His research has been recognized for excellence by the Society for Biomaterials. He is currently the director of the Peripheral Nerve Research Laboratory at Washington University School of Medicine.