The global respiratory gram-positive bacterial pathogen Streptococcus pneumoniae (the pneumococcus), is a resident commensal and colonizes the nasopharynx in healthy children and adults. Currently, there are 100 different capsular serotypes of pneumococci known. However, when the bacteria migrate into the lower respiratory tract and invade organs it causes fatal diseases such as pneumonia, septicemia, and meningitis collectively termed as invasive pneumococcal diseases (IPD). Pneumococcal pneumonia is the leading cause of mortality and morbidity due to lower respiratory tract infections worldwide in young children below 5 years. According to the WHO, IPD accounts for 600,000-800,000 deaths every year. Therefore, the WHO has classified S. pneumoniae as a priority pathogen that needs urgent research into its pathogenesis and development of new and effective antibiotics.
Pneumococci express several virulence factors that promote their spread and survival within the human host. The expression of a polysaccharide capsule surrounding the bacterial cell wall protects the bacteria against phagocytosis and complement attack. Pneumococci express the pore forming toxin, pneumolysin and other surface virulence proteins (such as adhesins, factor H binding proteins, neuraminidases etc.), pilus, pyruvate oxidase (SpxB), IgA1 protease, and exoglycosidases, to promote its survival within the host. For several decades, the pathogenic lifestyle of pneumococci has been presumed to be solely extracellular. However, recent studies have found that these opportunistic bacteria have intracellular phase within immune cells such as dendritic cells and resident splenic, alveolar macrophages as well as brain endothelial cells and cardiomyocytes to promote infection spread and escape immune clearance. This has brought about a paradigm shift in the field of pneumococcal pathogenesis.
This Research Topic aims to highlight the recent advances in the field of pneumococcal infection biology with a focus on the immunomodulatory and immune-evasion mechanisms adopted by the pneumococcus. The scope of this Research Topic welcomes original research articles and reviews on (but not limited to) the following pneumococcal infection related themes:
1. Pneumococcal interaction with host immune cells and immune evasion
2. Immunomodulation during pneumococcal infections
3. Bacterial pathogenesis
4. Virulence factors- mechanisms of action and regulation
5. Biofilms and antibiotic resistance
6. Super-infections and co-morbidity
The global respiratory gram-positive bacterial pathogen Streptococcus pneumoniae (the pneumococcus), is a resident commensal and colonizes the nasopharynx in healthy children and adults. Currently, there are 100 different capsular serotypes of pneumococci known. However, when the bacteria migrate into the lower respiratory tract and invade organs it causes fatal diseases such as pneumonia, septicemia, and meningitis collectively termed as invasive pneumococcal diseases (IPD). Pneumococcal pneumonia is the leading cause of mortality and morbidity due to lower respiratory tract infections worldwide in young children below 5 years. According to the WHO, IPD accounts for 600,000-800,000 deaths every year. Therefore, the WHO has classified S. pneumoniae as a priority pathogen that needs urgent research into its pathogenesis and development of new and effective antibiotics.
Pneumococci express several virulence factors that promote their spread and survival within the human host. The expression of a polysaccharide capsule surrounding the bacterial cell wall protects the bacteria against phagocytosis and complement attack. Pneumococci express the pore forming toxin, pneumolysin and other surface virulence proteins (such as adhesins, factor H binding proteins, neuraminidases etc.), pilus, pyruvate oxidase (SpxB), IgA1 protease, and exoglycosidases, to promote its survival within the host. For several decades, the pathogenic lifestyle of pneumococci has been presumed to be solely extracellular. However, recent studies have found that these opportunistic bacteria have intracellular phase within immune cells such as dendritic cells and resident splenic, alveolar macrophages as well as brain endothelial cells and cardiomyocytes to promote infection spread and escape immune clearance. This has brought about a paradigm shift in the field of pneumococcal pathogenesis.
This Research Topic aims to highlight the recent advances in the field of pneumococcal infection biology with a focus on the immunomodulatory and immune-evasion mechanisms adopted by the pneumococcus. The scope of this Research Topic welcomes original research articles and reviews on (but not limited to) the following pneumococcal infection related themes:
1. Pneumococcal interaction with host immune cells and immune evasion
2. Immunomodulation during pneumococcal infections
3. Bacterial pathogenesis
4. Virulence factors- mechanisms of action and regulation
5. Biofilms and antibiotic resistance
6. Super-infections and co-morbidity