Researchers at the Brigham and Women's Hospital (BWH), Harvard Medical School, have reported that a sugar polymer known as PNAG (or rather beta-1-6-linked poly-N-acetyl glucosamine) is made by more bacterial, fungal and other microbial organisms than previously thought – and the fact that it's common to several pathogens makes it a promising target for a broad-spectrum vaccine. In the study, due to be published in Proceedings of the National Academy of Sciences (week of May 27, 2013), the researchers created vaccine-induced, non-human-derived antibodies against a synthetic form of PNAG, and also tested a human-derived antibody that responded to both the natural and synthetic forms of PNAG. When they tested these antibodies in mice, the researchers found that they conferred protection against infections caused by a range of unrelated pathogens, including Streptococcus pyogenes, Streptococcus pneumoniae, Neisseria meningitidis serogroup B, Candida albicans, and also a strain of malaria in mice. Furthermore, the researchers also found PNAG on the microbes that cause gonorrhoea, trichomoniasis, typhoid, otitis media and tuberculosis.
“While we have known for awhile that staphylococci and several other bacteria including E. coli and some other microbes that cause hospital infections make PNAG, the new work expands this to a ‘top 10 to 20’ list of many of the major causes of serious human infections,” said Gerald Pier, PhD, Division of Infectious Diseases, BWH Department of Medicine, Professor of Medicine, Microbiology and Immunobiology, Harvard Medical School, senior study author. “The possibility to use one agent to target so many different organisms including gonorrhea, TB and malaria is very exciting and unprecedented so far in the field of infectious diseases. However, whether or not one vaccine will work for any of these organisms, let alone many of them, will only be known once the vaccines and antibodies are thoroughly tested in humans.”
What do you think? Do you think PNAG has the potential to offer a widely protective vaccine? You can leave a comment in the box below, or on LinkedIn group discussion.
If you want to know more about strategy and innovation in vaccines, you might be interested in attending the World Vaccine Congress Asia 2013, 17-20 June 2013, Singapore. Want more from Vaccine Nation? Sign up to our newsletter for free here.