Research 

Colorful example of computational research

The Lewin Lab is working on several projects to study Feline herpesvirus (FHV), which can cause painful and blinding ocular disease in domestic cats. We have also previously collected and assessed FHV obtained from cheetahs.

1. Antiviral Use in Shelter Cats:

The lab is receiving funding from the Morris Animal Foundation and Stokes Pharmacy to study the effect of antiviral medications for the treatment of FHV in shelter-housed cats. This study will utilize cutting-edge DNA sequencing technology to study the structure of the virus. For additional information on this exciting study please see the study information page on the Morris Animal Foundation website.

Cat being examined

LEFT: Dr. Melanie Mironovich hard at work, RIGHT: A study participant, feeling better after some treatment!

**Update February 2021** Our 2020 Summer Scholar, Mikayla Sanford, presented 'Assessing Potential for Antiviral Resistance in Feline Herpesvirus' at the 2021 LSU Phi Zeta research day. Well done Mikayla!

**Update August 2022** Dr. Mironovich (2020-2021 Ophthalmology Research Intern) will be presenting the results of her research at the 2022 ACVO annual conference in Palm Springs California.'

2. Genetic Sequencing of Feline Herpes Virus:

We have also been busy working with our collaborator at the LSU Center for Computation and Technology, Dr. Lyndon Coghill, on a genome assessment of FHV isolates to assess if certain regions of DNA are associated with disease severity in naturally-infected cats. To view the results of this study, please visit the Virus Genes website. 

3. New Treatment for Feline Herpes Virus:

The lab has been working on assessing the safety of a new antiviral eye medication for use in cats with Feline Herpes Virus. The results have recently been published in the Journal of Feline Medicine and Surgery. Check it out!

4. FHV in Cheetahs:

A summer scholar student, Morgan Marino, worked with the Lewin Lab in the summer of 2021 and performed a comprehensive investigation into the origins of infection in several cheetahs. Her discoveries will lead to improved strategies for prevention of this infection in these animals.

**Update November 2021** To read this exciting paper, please check out the MDPI Viruses website.

**Update August 2022** Morgan will be presenting the results of her research at the 2022 ACVO annual conference in Palm Springs California.'

5. Antiviral resistance to Feline Herpes Virus:

Nikole Ineck (previous VCS Research Associate and Lewin Lab member) is working on a project to determine the impact of short term, low dose antiviral use in cats naturally infected with Feline herpesvirus. She is using a combination of sophisticated bioinformatic modelling techniques and benchtop testing to assess if the use of antiviral drugs in this way drives resistance in this virus.  

6. Ocular bacterial microbiome changes with Feline Herpes Virus infection:

Dr. Erinn Mills (2022-2023 Ophthalmology Research Intern) will be working to assess the ocular bacterial microbiome in cats with feline herpes virus infection. It is thought that secondary bacterial infection can play a role in disease severity in naturally infected animals. Dr. Mills will compare samples from cats with the virus which improved versus those which did not to assess the role of bacterial infections.

With funding support from the USDA, the lab is working on the collection of ocular microbiome data from cattle with 'Pink Eye' (infectious bovine keratoconjunctivitis) and 'Cancer Eye' (ocular squamous cell carcinoma). These diseases are very economically important to livestock producers and the development of novel therapeutics is a top priority. Using this microbiome data we hope to gain novel insights into these diseases which will direct the development of new treatments.

As of July 2021 we are actively seeking animals to enroll in this study. Enrollment will continue until the required number is met. If you are a producer and would like to discuss this study for your affected herd, please contact Hannah Gafen using lsueyestudy@lsu.edu or call her on 225-578-9526.

**Update November 2021** Our laboratory is taking a temporary pause in sample collection to process the samples collected so far. We had a great reponse to our request for samples -thank you to everyone who helped with this so far!

**Update August 2022** Dr. Gafen will be presenting the results of her research at the 2022 ACVO annual conference in Palm Springs California.'

Dr. Gafen with cow

ABOVE: Dr. Hannah Gafen, checking out some young dairy cattle for evidence of 'pink eye'

With funding from the LSU EHSP support fund, we have acquired samples from horses with equine herpes virus for phylogenomic sequencing analysis. Ugochi Emelogu (VCS Research Associate) is heading up this analysis and is expected to determine the frequency of known variants in US based isolates as well as be able to detect novel variants. Using host disease data, she will also be able to determine the relationship between viral variants and host disease severity.

 With our collaborator at Cornell School of Veterinary Medicine, Dr. Eric Ledbetter, we are assessing the genome structure of various isolates of Canine herpesvirus, which causes eye disease in domestic dog populations. By understanding the structure of this virus in more detail, we hope to improve prevention and treatment of dogs with this disease. This project is sponsored by the American Kennel Club Canine Health Foundation. http://www.akcchf.org/

 

**Update December 2020** The results of this exciting study have just been published in the Viruses journal. This open-access paper can be found here!

The group has recently been working with Angela Yoon (LSU DVM candidate) to assess the use of different tests for dry eye in dogs in a variety of environmental conditions. The results will allow for improved interpretation of the test in this species. Please check out the Veterinary Ophthalmology website to read the paper!

**Update October 2020: We are pleased to announce that based on Angela's initial work, another paper has just been accepted by Veterinary Ophthalmology, demonstrating the differences between strip types obtained from different manufacturers. The paper is available on the Veterinary Ophthalmology journal website.

Dr. Angela Yoon

Angela Yoon presenting the results of her research at Tufts University, Aug 2019

Dogs which are scheduled to have cataract surgery at LSU School of Veterinary Medicine are currently being enrolled in a trial to assess the use of a medication to prevent high pressure after surgery. If you are interested in hearing more about this study, please contact the ophthalmology team at LSU SVM directly by email at lsueyecare@lsu.edu and provide your contact information.

**Update August 2022** Sample collection for this project is now complete. Dr. Jennifer Hu (2022-2023 Rotating small animal intern) is presently working on assembling the data for further analysis.

The lab has received funding from a USDA sponsored program to study antiviral treatments for bovine herpesvirus.

Dr. Chris Alling will be leading efforts along with help from virologist Dr. Muzammel Haque to find the best treatment for this virus which causes debilitating eye and lung disease in cattle populations worldwide.

**Update February 2021** Dr. Chris Alling presented 'Assessment of Topical Ophthalmic Cidofovir for Treatment of Bovine Herpesvirus-1 Infection in Cattle Using an Ex Vivo Model' at the 2021 LSU Phi Zeta Day and won 2nd place for the best basic science poster (house officer). Well done Chris!

**Update November 2021** Dr. Alling has just had this work published in the MDPI journal. Please go to the MDPI Viruses website to check out this open-access paper.

The members of the lab have recently completed data collection for a project assessing the use of two instruments to measure eye pressure in horses. The data obtained will help ensure consistent measurements are obtained when veterinarians use these instruments. Please visit the Equine Veterinary Journal for more information!

We are also working on a separate project with  Dr. Rebekah Joyner (LSU DVM 2020 graduate), assessing the effect of various sedation protocols on eye pressure in horses. This data will allow for accurate interpretation of intraocular pressure in horses with glaucoma and uveitis. The results of this study have recently been published in the Equine Veterinary Journal!

**Update September 2020** Dr. Joyner has presented the results of her study at the annual 2020 American College of Veterinary Ophthalmologists conference. This international event is one of the largest forums for the dissemination of research related to ocular disease in animals. The presentation was well received by the online audience. Well done Dr. Joyner!

Dr. Pilar Camacho has been leading a project to assess the use of ophthalmic tests in Leopard Geckos. This information will be of vital importance to veterinarians who are treating this species. Please visit the Veterinary Ophthalmology journal to read this paper!

The lab is currently involved in a project assessing the use of nanoparticle delivery agents on equine corneal tissue using a novel explant system. Dr. Renee Carter, an ophthalmologist at LSU and leader of this project, is working with the lab to determine the suitability of these new nanoparticles for use in eye medications in horses.

Dr. Melanie Mironovich is working on an exciting project to assess the impact of commonly used ocular diagnostic medications on the growth of bacteria isolated from ocular swabs. These medications include the drops used to dilate your pupils at the eye doctor! Using sophisticated techniques, she will determine if these medications have any effect on the quantity or type of bacteria which can be subsequently isolated from treated eyes. These results will be important information for both veterinary and human ophthalmologists!

**Update February 2021** Dr. Melanie Mironovich presented 'In-vivo Antimicrobial Activity of Topical Ocular Diagnostic Medications' at the 2021 LSU Phi Zeta Day. Well done Melanie!

**Update June 2021** The paper presenting this work has just been published in Veterinary Ophthalmology and accepted for presentation at the international 2021 American College of Veterinary Ophthalmology conference, to be held in Indianapolis, IN.

 

For a complete list of work by Dr. Lewin, please visit his LSU faculty page or Google Scholar page.

Previous research performed by Dr. Lewin and others at the University of Wisconsin; Madison:

Herpes Virus Genomics

Dr. Lewin has previously published work assessing the genomics and phylogenetics of feline herpesviruses and other varicelloviruses:

Lewin AC, Kolb AW, McLellan GJ, Bentley E, Bernard KA, Newbury SP, Brandt CR. Genomic, recombinational and phylogenetic characterization of global feline herpesvirus 1 isolates. Virology. 2018 May 1;518:385-97.

Kolb AW, Lewin AC, Trane RM, McLellan GJ, Brandt CR. Phylogenetic and recombination analysis of the herpesvirus genus varicellovirus. BMC genomics. 2017 Dec;18(1):887.

Exotic Animal Ophthalmology

Dr. Lewin has previously published work assessing various ocular parameters in exotic animals:

Lewin AC, Hausmann JC, Miller PE. Intraocular pressure and examination findings in three species of central and south American tree frogs (cruziohyla craspedopus, cruziohyla calcarifer, and anotheca spinosa). Journal of Zoo and Wildlife Medicine. 2017 Sep;48(3):688-93.

Lewin AC, Miller PE. Calibration of the TonoVet and Tono‐Pen Vet tonometers in the porcine eye. Veterinary ophthalmology. 2017 Nov;20(6):571-3.

Snyder KC, Lewin AC, Mans C, McLellan GJ. Tonometer validation and intraocular pressure reference values in the normal chinchilla (Chinchilla lanigera). Veterinary ophthalmology. 2018 Jan;21(1):4-9.