William F. Goins, PhD

Recently, I have pursued the use of HSV vectors for realtime in vivo non-invasive imaging of vector-mediated gene transfer. Work in collaboration with Dr. Eric Ahrens at CMU has exploited the expression of novel MRI reporter genes such as ferritin, from both adeno and HSV vectors for enhanced real-time imaging of vector-mediated gene expression in the CNS of rodents. This initial work resulted in a publication in Nature Medicine in 2006. Further studies will employ other novel MRI reporters in efforts to enhance the signal as part of a NIH funded project held by Dr. Ahrens and myself. In addition, I will take advantage of these vectors in other studies such as those in the retina described below, and in models of neuroprotection and oxidative tissue damage. In a project dealing with the use of HSV vectors to block the damage to heart vessels caused by ischemia-reperfusion injury that occurs during heart transplantation, in collaboration with Dr. Joseph Glorioso I have already shown that the addition of ferritin to the vector produced a block in endothelial cell apoptosis and increased cell survival in response to the generation of reactive oxygen species by treatment of the cells with a toxic agent such as hydrogen peroxide. Another project will employ these vectors to in vitro and in vivo models of neurodegeneration observed in HIV neuropathy, where the expression of the HIV proteins TAT and gp120 have been shown to be the causative agents behind the devastating neuropathology. In another new area of research in collaboration with Dr. Neil Hukriede, we have exploited the HSV vector system to transduce both zebrafish and frog oocytes as a new delivery vehicle to express transgenes of interest in these two developmental biology systems. Proposed studies will examine the unique interaction of HSV with these vertebrate cells/tissues. We are currently gathering the final data for a manuscript dealing with the ability of the vector to readily transduce frog oocytes and express genes that initiate the developmental cascade down the pathway of kidney formation. 

Other recent work has been initiated to target HSV vectors through an understanding of the molecular events involved in HSV entry in collaboration with Dr. Glorioso and his group. We have made considerable progress in these efforts that has lead to some recent publications concerning the entry of HSV and another alphaherpesvirus EHV-1. A recent goal is to target the vector to specific neuronal cell populations in an effort to decipher the specific afferent neurons involved in different pain responses. 

A prior goal of my work was the characterization of the HSV latency-associated transcript promoter (LAP) that is unique within the virus since it can drive expression of a transgene cassette from quiescent viral genomes in latently infected neurons. Thus, this promoter has been ideal for expressing foreign genes from HSV vectors in cells of the peripheral nervous system (PNS). Using this promoter, we have achieved long-term expression of nerve growth factor (NGF), GDNF and other therapeutic gene products. We are currently testing these and other vectors in collaboration with Dr. James Goss in animal models of diabetic neuropathy. In collaboration with Drs. Glorioso, Goss, Yoshimura and de Groat, we have demonstrated that NGF expression from the vector has a positive effect on bladder function in diabetic animals. In addition, vector-mediated NGF synthesis resulted in the restoration of a normal H-wave in animals treated with pyridoxone, suggesting that NGF has a protective effect in these animal models of neuropathy. 

We have also achieved similar therapeutic effects expressing enkephalin and other anti-nociceptive factors to treat chronic pain in a number of animal models. These studies again take advantage of the natural biology of HSV to readily transduce the target cells. We will continue to address the therapeutic potential of these and other vectors in models of bladder pain and also in animal models of erectile dysfunction. 

Some new efforts have focused on the use of herpes simplex virus (HSV) vectors to treat genetic disorders of the eye such as macular degeneration and the use of HSV vectors as a vaccine platform for the development of a vaccine for hepatitis C virus. The work to further develop HSV as a vaccine vector is being performed in collaboration with Dr. Joseph Mester at the University of Northern Kentucky. HSV represents an ideal delivery vehicle for the eye since HSV infects the eye as part of the natural biology of the virus. Current gene therapy approaches use other vectors such as AAV, which are immunogenic and can integrate into the host DNA and may eventually cause tumors, while HSV can remain dormant within structures within the eye causing no pathology as I have shown in collaboration with Dr. Robert Hendricks of the Eye & Ear Institute. The goal of these studies will be to utilize the ability of HSV to naturally infect the pigmented epithelial cell layer of the retina (RPE) and express trophic factors such as MnSOD, heme oxeygenase-1, ferritin, GDNF, NGF and NT-3 in an attempt to ameliorate nerve damage in animal models of retinal disease. Since for all of the forms of retinal disease such as macular degeneration, multiple genes are affected in diseased patients making it difficult to perform gene replacement therapies. Since they all have similar pathologies, a strategy to express trophic factors is more likely to yield measurable results. Using the latency active promoter (LAP2) that I discovered as a postdoctoral fellow, the goal is to express the factors at low levels long-term in the RPE. Since HSV vectors possess the capability of carrying multiple genes in a single vector backbone, it will be easy to introduce vectors that express multiple therapeutic genes at once.