Bebhinn Treanor originally wanted to be a doctor - that is, until she had the chance to work in a neuroscience lab as an undergraduate student.
The opportunity made her realize there was more than one path to improving human health.
"Getting to see what was happening in cells and tissues at a molecular level was really thrilling to me and transformative for my career," she says. "I loved the sense of discovery in addressing questions that nobody else had considered."
Now an immunologist, professor in the department of biological sciences at the University Toronto Scarborough and Canada Research Chair in spatially-resolved biochemistry, Treanor has made a significant impact in the field through her research on autoimmune diseases, human immunodeficiency virus (HIV) and COVID-19 - and is turning her attention to assessing the toxicity of environmental pollutants.
She says her journey into the world of immunology officially began during her graduate studies at Imperial College London - though her curiosity about the field began much earlier.
"I'd had a lot of questions about autoimmune diseases since high school, as my best friend's mom had lupus," Treanor says. "I've also had allergies since I was a young child, and my sisters and I have hypothyroidism from an autoimmune disease, so immunology was an area that fascinated me."
She completed her PhD in the lab of Imperial College's Daniel M. Davis, working collaboratively with colleagues in physics and chemistry to study how natural killer (NK) cells, a type of white blood cell critical to the immune system, distinguish healthy cells from cancer cells. During her postdoctoral studies at the Institute of Cancer Research in London, U.K., she shifted her focus to examining how B cells recognize pathogens and produce protective antibodies.
Treanor arrived at U of T Scarborough in 2011 and began building on the B-cell investigations she had started during her postdoc.
"B cells are critical in the defense against infections, but if their activation isn't controlled it can lead to a sort of aberrant recognition and attack on your own cells and tissues, which is what happens in autoimmune diseases," says Treanor.
Using advanced optical microscopy techniques, her U of T lab examines the mechanisms that control B cell activation. Recently, her lab identified two important molecules: the ion channel TRPM7, which is essential for B cell development; and galectin-9, which helps prevent B cells from going rogue and attacking the body.
In 2015, a chance encounter at a Canadian Institutes of Health Research meeting of new investigators sparked a new line of research - and a breakthrough. "I met Jean-Philippe Julien from SickKids, and we knew immediately that our shared interest in B-cell responses and antibodies was worth pursuing collaboratively," says Treanor of the senior scientist at the Hospital for Sick Children and associate professor in U of T's Temerty Faculty of Medicine.
The two began a collaboration that led to the engineering of a "super molecule" that combines multiple antibodies or antibody fragments in different configurations on a single, naturally occurring protein. They named it the Multabody (MULTi-specific, multi-Affinity antiBODY) platform because it can target several varieties of a pathogen, not just one specific type. The molecule also enables increased binding strength, or affinity, between the various antibodies on its surface and a pathogen.
Together, these qualities made the Multabody a potentially powerful therapeutic platform for treating infectious diseases such as HIV, which was the initial focus of their research. However, when the pandemic struck, Treanor and Julien shifted their attention to the COVID-19 virus and demonstrated that the Multabody platform was up to 10,000 times more potent against the virus than conventional antibodies and had the ability to address virus variants.
In 2020, their Multabody discovery laid the foundation for the launch of Radiant Biotherapeutics , which aims to develop therapies for cancer, autoimmune and infectious diseases. Four years later, the company, with offices in Toronto and Philadelphia, secured a US$35-million investment to advance the technology for clinical use.
Meanwhile, Treanor's B cell research continued. She recently branched into a yet another direction following another fortuitous meeting - this time with Satyaki Rajavasireddy, assistant professor in the department of biological sciences at U of T Scarborough.
"We were at a faculty coffee gathering and got talking about what's known as 'forever chemicals,'" she says, referring to the thousands of persistent organic pollutants (POPs) that threaten human and ecological health. While some POPs have been linked to health issues such as immune dysfunction, cancer and infertility, their effects on people and other organisms remain largely unknown, resulting in inadequate regulation.
Treanor, Rajavasireddy and their team received funding last summer from U of T Scarborough's clusters of scholarly prominence program to develop a scalable technique for screening toxic POPs and assessing their impacts on diverse species. Treanor is focused on studying the effects of POPs on B cells and the immune response.
She credits the diversity of research and expertise at U of T and its hospital partners - and at U of T Scarborough in particular - for a rewarding career that has evolved in unexpected ways.
"Bringing together the POP cluster, for example, wouldn't have been possible without UTSC's diverse strengths in the biological sciences and its interdisciplinary approach."
She's also committed to helping others navigate their own career journeys.
"Acting as a mentor to my students and colleagues here at UTSC, but also in the wider field of immunology, is very important to me. I'm driven to support others to find success on their own path, as I did."
