Capsular Polysaccharide
Streptococcus pneumoniae Vaccine
Vaccines against Streptococcus pneumoniae
from James C. Paton writing in Vaccine Design: Innovative Approaches and Novel Strategies
Existing vaccines against Streptococcus pneumoniae are targeted at the capsular polysaccharide (PS) of which there are 91 distinct serotypes. Polyvalent purified PS vaccines are immunogenic in healthy adults, but not in high risk groups such as young children and the elderly. Development of PS-protein conjugate vaccines has overcome the poor immunogenicity of PS in children, but the protection imparted is strictly serotype-specific, and the number of included serotypes is even more restricted than in the PS vaccine formulations. Widespread introduction of conjugate vaccines in developed countries has dramatically reduced the incidence of invasive pneumococcal disease due to serotypes included in the vaccine. However, these benefits are being eroded by increases in the incidence of disease caused by non-vaccine serotypes. Conjugate vaccines are also expensive, limiting their use in developing countries, where the burden of pneumococcal disease is greatest. Clearly, there is an urgent need to develop alternative pneumococcal vaccines that are (i) inexpensive, (ii) immunogenic in young children, and (iii) provide protection against all pneumococci regardless of serotype. Of particular importance are vaccines comprising pneumococcal proteins that contribute to virulence and are common to all serotypes.
Further reading: Vaccine Design: Innovative Approaches and Novel Strategies | Bacterial Polysaccharides: Current Innovations and Future Trends
from James C. Paton writing in Vaccine Design: Innovative Approaches and Novel Strategies
Existing vaccines against Streptococcus pneumoniae are targeted at the capsular polysaccharide (PS) of which there are 91 distinct serotypes. Polyvalent purified PS vaccines are immunogenic in healthy adults, but not in high risk groups such as young children and the elderly. Development of PS-protein conjugate vaccines has overcome the poor immunogenicity of PS in children, but the protection imparted is strictly serotype-specific, and the number of included serotypes is even more restricted than in the PS vaccine formulations. Widespread introduction of conjugate vaccines in developed countries has dramatically reduced the incidence of invasive pneumococcal disease due to serotypes included in the vaccine. However, these benefits are being eroded by increases in the incidence of disease caused by non-vaccine serotypes. Conjugate vaccines are also expensive, limiting their use in developing countries, where the burden of pneumococcal disease is greatest. Clearly, there is an urgent need to develop alternative pneumococcal vaccines that are (i) inexpensive, (ii) immunogenic in young children, and (iii) provide protection against all pneumococci regardless of serotype. Of particular importance are vaccines comprising pneumococcal proteins that contribute to virulence and are common to all serotypes.
Further reading: Vaccine Design: Innovative Approaches and Novel Strategies | Bacterial Polysaccharides: Current Innovations and Future Trends
Group B Streptococcus Vaccine
Toward the Development of a Universal Vaccine Against Group B Streptococcus
from Roberta Cozzi, John L. Telford and Domenico Maione writing in Vaccine Design: Innovative Approaches and Novel Strategies
Group B Streptococcus (GBS) is one of the most common cause of life-threatening bacterial infections in infants and is also an emerging pathogen among adult humans, especially in the elderly, immunocompromised and diabetic adults. Capsular polysaccharide based vaccines of the most common serotypes present in the United States and Europe are in an advanced stage of development but they are not effective against serotypes present in other parts of the world. Many protein antigens have been studied for the discovery of an effective universal vaccine that could overcome serotype specificity. Thanks to reverse vaccinology and new technologies, a vaccine combination based on the pilus proteins has been discovered for the development of a universal GBS vaccine that is potentially capable of preventing all GBS infections.
Further reading: Vaccine Design: Innovative Approaches and Novel Strategies | Pili and Flagella: Current Research and Future Trends
from Roberta Cozzi, John L. Telford and Domenico Maione writing in Vaccine Design: Innovative Approaches and Novel Strategies
Group B Streptococcus (GBS) is one of the most common cause of life-threatening bacterial infections in infants and is also an emerging pathogen among adult humans, especially in the elderly, immunocompromised and diabetic adults. Capsular polysaccharide based vaccines of the most common serotypes present in the United States and Europe are in an advanced stage of development but they are not effective against serotypes present in other parts of the world. Many protein antigens have been studied for the discovery of an effective universal vaccine that could overcome serotype specificity. Thanks to reverse vaccinology and new technologies, a vaccine combination based on the pilus proteins has been discovered for the development of a universal GBS vaccine that is potentially capable of preventing all GBS infections.
Further reading: Vaccine Design: Innovative Approaches and Novel Strategies | Pili and Flagella: Current Research and Future Trends