Our Research

Our research team has a major research focus on the bacterial pathogens Streptococcus pyogenes and Staphylococcus aureus using a range of multidisciplinary techniques including bacterial genetics, immunology, protein biochemistry, functional genomic approaches, and in vivo models of infectious disease.

One major interest is the study of bacterial toxins. Superantigen toxins function by directly activating T cells of the adaptive immune system, and we are interested in understanding how superantigens contribute to the colonization and rheumatic heart diease caused by S. pyogenes. We are also very focused on understanding how the cytolytic toxins of S. pyogenes contribute to colonization and skin infection. Using our in vivo models, we are working on evaluating a number of potential vaccine targets for S. pyogenes. This work is funded by a project grant from the Canadian Institutes of Health Research entitled “Novel vaccine antigens for S. pyogenes” (2021-2026).

With Staphylococcus aureus, we are working to understand how superantigen influence nasal colonization as well as invasive disease such as bacteremia. We now know that once S. aureus has become invasive, the superantigens drive a pathogenic interferon-gamma response that inhibits macrophage function. We are now very focused on understanding the role of superantigens in the transition of S. aureus from nasal colonizer to invasive pathogen. This work has been generously funded by the Canadian Institutes of Health Research entitled “Staphylococcus aureus at the commensal-pathogen interface: the superantigen paradox” (2019-2024).

We also have a major interest in the linkage between carbohydrate metabolism and antimicrobial activity from S. pyogenes. The major biological niches for S. pyogenes include the nasopharynx and the skin, and we are working to understanding how this bacterium can compete with other microorganisms within this limited biological niche and how carbohydrate metabolism can influence this. This work is generously funded by the Natural Sciences and Engineering Research Council of Canada (2019-2024).

In addition, S. aureus is the cause of menstrual-associated toxic shock syndrome and this is mediated by a specific toxin known as the toxic shock syndrome toxin-1 (TSST-1). We have a major interest in understanding the detailed molecular mechanisms that control the expression of TSST-1 in the vaginal environment. This work has previously been generously funded by the Kimberly-Clark Corporation.

As superantigens activate cells of the adaptive immune system, we also have significant efforts to engineer these proteins as targeted anti-cancer immunotherapeutics. This work has previously been supported by the Cancer Research Society.

Meet the talented Team that work on these projects!