Dean Lab Research Projects

Vaccine Development Against SARS-CoV-2

Using our understanding of potential immune correlates against feline enteric coronavirus and our extensive background with Lactobacillus acidophilus as an orally-delivered mucosal vaccine platform, we are currently engineering vaccine candidates. This subunit vaccine strategy targets key functional regions of the virus while seeking to avoid the immune enhancement that is commonly observed with traditional vaccine approaches. Our goal is to quickly move a vaccine candidate through preliminary immunogenicity studies and determine the potential of the vaccine for use in humans and domestic animals, particularly cats.

Human Rotavirus Vaccine Development

Despite the broad availability of two attenuated live oral rotavirus vaccines, rotavirus continues to cause 215,000 deaths in children yearly in developing countries where efficacy of the current vaccines is low (50-60%). We have developed the Gram-positive lactic acid probiotic bacterium Lactobacillus acidophilus (LA) as an oral subunit vaccine against rotavirus through chromosomal integration and expression of rotaviral capsid proteins. Our vaccine platform includes three immune stimulating adjuvants selected to stimulate both a systemic and local (mucosal) immune response against rotavirus epitopes shown to be protective against viral infection and disease.

Investigating the Relationship Between Recombinant Lactobacillus acidophilus and the Local Bacterial Microbiome

We are studying the dynamic relationship between the mucosal immune system and the local bacterial microbiome to determine how this relationship may be affected when the live probiotic L. acidophilus oral vaccine platform is used. We are evaluating differences in members of the bacterial microbiome that are coated in IgA from the intestinal mucosal immune system longitudinally throughout the vaccination regimen. This will aid in evaluating the safety of our vaccine by identifying any off-target effects on the resident microbiome. We are also exploring the essential role of NOD2 expression in antigen presenting cells for the mucosal immunogenicity of the L. acidophilus vaccine platform.

Vaccine Development for the Prevention of Feline Infectious Peritonitis Virus (FIP)

FIP is a lethal viral disease affecting cats worldwide that arises out of the enteric virus, Feline Enteric Coronavirus (FECV). To date a vaccine against FIP has been elusive. We are utilizing a novel approach and targeting the enteric virus with the aim of preventing the emergence of FIP. We have been developing an oral vaccine delivery system using the probiotic bacterial family Lactobacillus. Our goal is to incorporate key subunits of the FECV spike protein into our probiotic vaccine platform in order to generate a protective mucosal immune response.

Improvements in Feline Infectious Peritonitis Virus (FIP) Diagnostics

The traditional diagnostic methods used for FIP have historically been complicated by cross-reaction to the fairly innocuous feline enteric coronavirus (FECV), making results difficult to interpret, and the information provided to cat owners and veterinarians minimal. In our lab we have identified a set of biomarkers within blood samples of cats infected with FIP that we can use to successfully differentiate cats with FIP from cats with FECV. While these results are preliminary, we have great hope that this research will soon be able to provide veterinarians and owners a more accurate test that is both faster and less invasive than the current gold-standard.