Simona Seizova

PhD student Simona Seizova in a garden
Ms Simona Seizova's PhD project took on a formidible opponent: Toxoplasma gondii, which is perhaps the most successful parasite in the world. Simona completed her studies in 2020, and is looking forward to taking up a postdoctoral position overseas, continuing to focus on parasitology. These are some of her reflections on being a student at the Institute.

PhD student Ms Simona Seizova (right) and her
supervisor Associate Professor Chris Tonkin

The single-celled Toxoplasma gondii parasite can make any vertebrate cell its host. In fact, between 30 and 80 per cent of the world’s human population is estimated to be chronically infected with Toxoplasma – a condition called toxoplasmosis. At its most serious, toxoplasmosis can cause blindness, birth defects and death.

Simona said T. gondii manipulates its host both at the cellular and organism level.

“It does this by releasing parasite factors into the host that interact with the host cell, making the parasite invisible to the body’s defence system. Often this occurs in the brain.

“I’m looking at how the parasite manipulates the brain, what parasite factors T. gondii uses and, in the bigger picture, how this can influence the behaviour of living beings,” Simona explained. “Maybe if we know how it does this, we can make it visible to the immune system and enable the body to clear the parasite.”

Making a difference

Simona grew up in Christchurch, New Zealand, and completed her undergraduate studies at the University of Canterbury, Christchurch.

“When we immigrated to New Zealand, my family lived in a disadvantaged neighbourhood in Christchurch, where there was very little opportunity,” Simona said.

“I want to show all children that no matter where you come from you too can be scientists or engineers or doctors; that you can use science to help your community.”

PhD student Ms Simona Seizova
PhD student Ms Simona Seizova looks at how Toxoplasma
gondii manipulates the brain

During her studies, a friend commenced a PhD at the Walter and Eliza Hall Institute, and recommended that Simona look into opportunities to study with Associate Professor Chris Tonkin’s laboratory.

“My friend said the Institute is top quality,” Simona said. “She was right. I particularly love having access to the Institute’s state-of-the-art Centre for Dynamic Imaging for my microscope work. It’s also fantastic to have people dedicated to supporting my scientific work outside of my direct discipline.”

One of Simona’s images of T. gondii – titled Parasite bouquet – was awarded third place in the Institute’s 2017 Art of Science exhibition.

“I have passion for art, and to be able to merge that with my love of science was so exciting,” Simona said.

“To see the image being used to encourage science communication and education gives me such a boost.”

Simona Seizova talking to camera

See PhD student Simona Seizova on Channel 11's science TV show Scope, explaining how she uses imaging techniques to study the parasite Toxoplasma gondii. 

(Watch from 16:50)