Gianne Souza Unfolds Equine Envelope Genes

Souza presents her poster to
Honors faculty Kim Andersen.

“It’s funny how things work out,” comments Honors College sophomore Gianne Souza on her work in a research lab that she began as just a freshman.  Her story, like her research, involves interesting developments.

Finding a research home

Souza came to Washington State University from Edmonds, Wash. intending to become a veterinarian. She decided that experience in research might boost her chance of getting into the program, so she spent two months contacting faculty hoping to find someone who would let a freshman assist in the laboratory.

Susan Carpenter, professor in the Dept. of Veterinary Microbiology and Pathology, was interested. “I met with Gianne and she struck me as a very bright individual,” recalls Carpenter.

“Before coming to Washington State, I was a faculty member at Iowa State University," she explains.  "They have a strong honors college where all students are required to complete a freshman project.  So I had worked with several freshman honors students in my past and knew that some were truly exceptional, as is Gianne.”

“Although she is young, she is eager and motivated. I thought Gianne had great potential, and decided to give her a chance."  She asked Souza to join her team.

Diagram of the Equine Infectious Anemia (EIA) lentivirus cut in half.

Lentivirus research

Under the tutelage of Carpenter and Rebecca Tallmadge, a post-doc from Cornell University, Souza began to research the envelope gene characteristics of Equine Infectious Anemia (EIA) lentivirus.   The envelope is the outer surface of the EIA virus, and the envelope proteins mediate interactions with the host cell that lead to infection.  A lentivirus is commonly known as a “slow virus,” one characterized by a long incubation period.  A well-known lentivirus among people is the Human Immunodeficiency Virus (HIV).

EIA—also known as “swamp fever”— is primarily transmitted to horses by bloodsucking insects, namely horseflies and deerflies; but it can also be passed through blood, saliva, milk, and body secretions, and through the use of contaminated surgical equipment, recycled needles and syringes and bits.  It is endemic in the Americas, parts of Europe, the Middle and Far East, Russia, and South Africa.  EIA can cause the breakdown of red blood cells, high fever, and even death in horses.

EIA uses several tactics to avoid the host immune system’s antibodies.  Souza’s job in the lab is to map what regions of the envelope gene are used by the lentivirus to make it unrecognizable by antibodies.Her research supports the presence of two different ways EIA uses its envelope gene to avoid detection ...

1. by changing the epitopes on the envelope.  An epitope is part of a macromolecule that is recognized by the immune system, specifically antibodies. If the epitopes of a lentivirus are constantly changing, the antibodies are unable to bind to the invading lentivirus.  
2. by glycan shielding.  This is where the envelope folds over itself, covering up the epitopes and shielding it from antibodies until the threat is gone.

Sophomore successes

In the second annual WSU Undergraduate Research Symposium on October 17, 2008, Souza presented a poster of her research titled, “Mapping Regions of Env Important in the Neutralization of Equine Infectious Anemia Virus.” The symposium’s only sophomore participant took home the top honors in the poster category.  She plans to present her research again at other venues, including the WSU Academic Showcase.

“Researching in a lab enhances my critical thinking skills and helps me deal with frustration, like when certain experiments did not run properly or did not get the results I needed,” Souza says when asked about the benefits of undergraduate research.

“I would recommend undergraduate research to anyone. Get out there and contact people, don’t be afraid, and get used to some rejection,” is her advice to fellow students.

“Undergraduate research has helped me focus on what I wanted to do and made me realize that I might not want to become a vet,” she says. Now approaching her junior year, Souza is leaning toward seeking a Ph.D. rather than a D.V.M.

“I hope to someday make discoveries in the lab that will affect veterinarians and others in the medical profession.”

Berkeley REU in summer

Souza's passion for research continues.  This summer, she will travel to the Bay Area to work and learn with a faculty mentor at the University of California—Berkeley as part of the National Science Foundation-funded Research Experience for Undergraduates (REU) program.