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Protection Against Invasive Infections in Children Caused by Encapsulated Bacteria.

ABSTRACT: The encapsulated bacteria Streptococcus pneumoniae, Neisseria meningitis, Haemophilus influenzae, and Streptococcus agalactiae (Group B Streptococcus) have been responsible for the majority of severe infections in children for decades, specifically bacteremia and meningitis. Isolates which cause invasive disease are usually surrounded by a polysaccharide capsule, which is a major virulence factor and the key antigen in protective protein-polysaccharide conjugate vaccines. Protection against these bacteria is largely mediated via polysaccharide-specific antibody and complement, although the contribution of these and other components, and the precise mechanisms, vary between species and include opsonophagocytosis and complement-dependent bacteriolysis. Further studies are required to more precisely elucidate mechanisms of protection against non-type b H. influenzae and Group B Streptococcus.

SUBMITTER: Sadarangani M

PROVIDER: S-EPMC6255856 | biostudies-other | 2018

REPOSITORIES: biostudies-other

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Protection Against Invasive Infections in Children Caused by Encapsulated Bacteria.

Sadarangani Manish M

Frontiers in immunology 20181120

The encapsulated bacteria Streptococcus pneumoniae, Neisseria meningitis, Haemophilus influenzae, and Streptococcus agalactiae (Group B Streptococcus) have been responsible for the majority of severe infections in children for decades, specifically bacteremia and meningitis. Isolates which cause invasive disease are usually surrounded by a polysaccharide capsule, which is a major virulence factor and the key antigen in protective protein-polysaccharide conjugate vaccines. Protectio ...[more]

PMID: 30515161

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