Development of a cost-effective protein-based combined glycoconjugate meningococcal-pneumococcal vaccine

点击翻译按钮获取中文摘要

The bacteria, Neisseria meningitidis (Nm) and Streptococcus pneumoniae (Sp), normally live in the back of the throat of man. However, they can also infect the blood and the brain causing a range of diseases such as pneumonia and meningitis. Meningitis is a deadly disease that can kill in less than 4 hours. The main sufferers of meningitis are children under the age of four. Some vaccines exist against Nm and Sp and have been used for many years, with a degree of success in limiting disease and preventing death. However, these vaccines do not provide full protection and are expensive. Thus, it is sensible to continue the search for new, cheaper Nm and Sp vaccines. In the first of two proof-of-principle studies, antibodies (molecules that protect us from harmful germs) were reproduced in the laboratory from patients recovering from meningitis. Antibodies taken from a Nm patient were able to kill a broad selection of Nm types; the killing ability of antibodies recognising Sp are currently being assessed. The Nm and Sp proteins recognised by these killer antibodies may be good vaccine candidates. In the second proof-of-principle study, a well-known Nm vaccine component was modified in the lab using advanced methods known as protein-glycan coupling technology (PGCT). This PGCT will allow for the production of cheaper-to-produce and effective vaccines. From the foregoing, the aims of this study are: to extend these promising preliminary studies and find more antibodies that kill Nm and Sp strains, especially those that are not covered by currently-available vaccines. Next, the the identity of the proteins on the surface of Nm and Sp to which the antibodies bind will be unequivocally determined - these are promising vaccine candidates. Subsequently, these proteins (preference will be given to those that are present in as many Nm and Sp types as possible) will be modified with PGCT. Finally, the ability of these promising vaccine candidates to induce the production of antibodies in animals will be tested - a necessary step prior to testing in humans. The ideal end-result of this study will be the identification of Nm and Sp proteins that can compose a cheaper combined vaccine that will prevent meningitis.