Understanding and preventing pneumococcal meningitis
Developing cheaper and more effective protection.
Dr Abiodun David Ogunniyi, Dr Layla Mahdi, Prof James Paton
- Start Date:
02 June 2008
Adelaide University, Adelaide, Australia
Streptococcus pneumoniae (the pneumococcus) is now the commonest cause of bacterial meningitis in children, the elderly, and adults with specific underlying medical conditions. The organism is responsible for the most severe form of bacterial meningitis in terms of the degree of sickness and death. The prevalence of antibiotic-resistant pneumococci is increasing rapidly, and available vaccines have major shortcomings. Therefore, the development of effective vaccines providing universal protection represents the best prospect for preventing meningitis and septicaemia. However, to date, the factors that make certain strains of pneumococci cause meningitis in humans are not fully understood, but the interplay between the bacteria and the host is believed to be complex.
What were the results?
In this study, researchers have used “state-of-the-art” technologies to
identify the pneumococcal factors that enable this organism to cross the
blood-brain barrier during infection to cause meningitis. One of the
factors identified was found to be important for attachment of the
bacteria to the cells of the brain of mice, and also induce the
production of harmful chemicals, which damage the cells of the brain
allowing the bacteria to survive and multiply.
The group also found that
the bacteria that have been engineered not to produce this protein do
not progress from the blood to the brain as readily, and produce less of
the harmful chemical that damages the brain. In addition, the antibody
raised against this protein is able to block the attachment and harmful
effects of the protein. The antibody also leads to a massive reduction
in the ability of the bacteria to cause meningitis.
Why is this important?
Further evaluation of these proteins is needed to see which of these factors is/are most important for inclusion in protein-based vaccines currently under development, but the aim would be to provide cheap, effective, and broad protection against pneumococcal meningitis, and invasive pneumococcal disease in general.
Extension of these findings could also be used to look into possible opportunities for the treatment of pneumococcal meningitis and other forms of meningitis.
The initial results from this study were published in a scientific journal in June 2012:Identification of a novel pneumococcal vaccine antigen preferentially expressed during meningitisJournal of Clinical Investigation 2012 Jun 1;122(6):2208-20
"We believe the findings from our work will facilitate and advance the objectives of The Meningitis Research Foundation to defeat meningitis and septicaemia through vital scientific research."
Dr Abiodun David Ogunniyi, University of Adelaide