As Streptococcus A cases continue to be prevalent around the world, a new nasal vaccine could provide long-term protection from the deadly bacteria. Griffith University researchers are spearheading the development of a Strep A vaccine which is currently in Phase 1 clinical trials in Canada and quickly advancing to Phase 2 efficacy trials.
The team’s new preclinical research, recently published in Nature Communications, shows an experimental liposome-based vaccine approach incorporating a conserved M-protein epitope from Strep A and an immunostimulatory glycolipid (3D(6-acyl) PHAD) administered via the nasal passage, can provide long-term mucosal protection against Strep A.
Lead author Dr Victoria Ozberk said studies have shown most pathogens enter or colonise via the soft tissue in the upper respiratory tract, which is essentially the highway to the rest of the body.
“This has the potential to be a world-first as there are currently no subunit vaccines that target the upper respiratory tract due to a lack of licenced immunostimulants suitable for human use,” Dr Ozberk said.
“We demonstrated that a liposomal mucosal vaccination strategy can induce robust local protective immunity.”
Associate Professor Manisha Pandey, Professor Michael Good, and their team from Griffith University’s Institute for Glycomics are leading the development.
Associate Professor Pandey said the team found PHAD plays an augmenting role in inducing enduring humoral and cellular immunity, which was evident for at least one-year post-vaccination.
“The longevity of immune response is a critical hallmark of successful vaccination and therefore the findings from this study are highly significant,” she said.
Professor Good said: “In the future, this vaccine platform could pave the way for other mucosal pathogens.”
Group A Streptococcus is a global human pathogen that leads to a wide range of infections from illnesses such as mild pharyngitis and impetigo to invasive diseases such as toxic shock syndrome, necrotising fasciitis, and cellulitis.
Source: Griffith University
