For those who contract Group A Streptococcal (GAS) infection, fast diagnosis and rapid treatment is critical. However, with many cases in low-socio economic areas left untreated, the infection can lead acute rheumatic fever (ARF), and in some instances, life-threatening rheumatic heart disease (RHD).
In a world-first move that could help save 350,000 lives per year, UNE PhD candidate Rukshan Rafeek has taken the first step in stopping RHD and ARF at the source. He’s developed a rodent model that mimics the cardiac and behavioural impacts of ARF and RHD in humans, which could help scientists develop a life-saving vaccine to prevent GAS infection across the globe.
“Until now, the lack of an animal model that mimics the autoimmune nature of ARF and RHD has been a major impediment in validating disease progression and assessment of the safety of streptococcal protein-based vaccine candidates that have the potential to initiate an autoimmune response,” says Rukshan.
“ARF is a multisystem disorder that can affect the joints, heart, brain and skin, but the most serious pathology is the irreversible damage to the heart. Approximately 30 percent of ARF and RHD patients also exhibit neurobehavioral complications. Using our Rat Autoimmune Valvulits (RAV) model, we have been able to replicate many symptoms and autoimmune responses observed in humans.”
This means scientists will have the opportunity to explore how ARF and RHD impact the brain and the heart simultaneously, which has not been possible until now.
The availability of this model provides us with a unique opportunity to test the safety of streptococcal protein-based vaccine candidates and to identify specific biomarkers of disease, as well as to determine the pathways that lead to disease and protection.
In addition, the development of a rodent model allows scientists to assess the safety of a potential vaccine before undergoing clinical trials on humans.
“Animal models are essential tools to determine the disease mechanisms and the development of therapeutics, including vaccines,” he says.
“The availability of this model provides us with a unique opportunity to test the safety of streptococcal protein-based vaccine candidates and to identify specific biomarkers of disease, as well as to determine the pathways that lead to disease and protection.”
Over the course of his PhD, Rukshan has also worked alongside his supervisor, Professor Natkunam Ketheesan, on a project that could lead to the development of an early diagnosis test for ARF and RHD.
With the autoimmune conditions affecting hundreds of thousands of people each year, the work UNE is doing in this space has the potential to drastically improve health outcomes around the world.
“Many ARF cases are missed or falsely diagnosed in developing countries and low socio-economic areas due to the unavailability of a rapid diagnostic test, therefore, development of an early point of care diagnostic test will enable timely and accurate diagnosis of ARF/RHD for a faster treatment and a reduction in the severity of the disease.
“Through our research, we have discovered a group of specific markers that will be used to develop a simpler diagnostic test that can be carried out by minimally trained health care staff. This will enable early detection and treatment of ARF/RHD, preventing the progression to cardiac failure.”
You can read more about Rukshan’s work at UNE in the Journal of Immunology and Cell Biology.
