S. pneumoniae is a leading human pathogen that causes a wide variety of diseases, ranging from otitis media to pneumonia, bacteremia, and meningitis in both children and adults. Pneumococcal infections can occur at any age but are more frequent in infants, the elderly and immunocompromised patients. Despite the development of effective treatments, the pneumococcus has remained a significant cause of morbidity and mortality worldwide. Because of this, a clear need for an effective vaccine for the prevention of disease exists. Currently licensed polysaccharide-based pneumococcal vaccines only elicit protective antibodies against the infection of serotypes that are included in the vaccine. In addition, invasive diseases attributable to non-vaccine serotypes of S. pneumoniae have increased greatly. Therefore, the search for new vaccine candidates that elicit protection against a broader range of pneumococcal strains is an important goal. To broaden the protection, the use of pneumococcal proteins represents a feasible and preferable alternative. Several pneumococcal proteins are currently under investigation as potential candidates for such a vaccine. One of these proteins, PspA has recently undergone phase one clinical trials in humans and has been found to be safe and highly immunogenic. PspA is a surface protein of S. pneumoniae that is found on all pneumococci and is broadly expressed among different serotypes of pneumococci.
Comparative Effects of Toll-Like Receptor Agonists on a Low Dose PspA Intranasal Vaccine against Fatal Pneumococcal Pneumonia in Mice: Zhenyu Piao, Keita Oma, Hirokazu Ezoe, Yukihiro Akeda, Kazunori Tomono and Kazunori Oishi
Last date updated on June, 2014