Protein-Based Pneumococcal Vaccines
Streptococcus pneumonia (penumococcus) is a significant human pathogenic bacterium. Despite its name, this organism may cause a number of pneumococcal infections other than pneumonia. These invasive diseases include septicemia, meningitis, otitis, sinusitis, conjunctivitis, sepsis, etc. Pneumococcal infection has become a major cause of death worldwide, particularly among children under two years old and the elderly. There are currently two types of pneumococcal vaccine available in the market, namely a 23-valent pneumococcal polysaccharide vaccine (23vPPV) and a 7~13-valent pneumococcal conjugate vaccine (PCV7~13). However, capsular polysaccharide vaccines primarily induce immunity through stimulation of B cells without the assistance of T cells and thus provide very weak protection for the elderly and young children whose immune systems are less well developed. By contrast, although capable of inducing a more robust immune response, glycol-conjugate vaccines only protect against 7-13 serotypes and may incur potential capsular seroconversion. The high manufacturing cost of conjugate vaccines also makes them impractical to be extensively utilized in developing countries. Therefore, we are in urgent need of effective broad spectrum pneumococcal protein vaccines that are applicable to all ages.
By refining our epidemiological knowledge of pneumococcal infections in China and some other developing countries, CanSino anticipates to develop an array of broad spectrum protein-based pneumococcal vaccine that are applicable in both seniors and young children.