AUTHOR=Sadarangani Manish 

TITLE=Protection Against Invasive Infections in Children Caused by Encapsulated Bacteria

JOURNAL=Frontiers in Immunology

VOLUME=9

YEAR=2018

URL=https://www.frontiersin.org/journals/immunology/articles/10.3389/fimmu.2018.02674

DOI=10.3389/fimmu.2018.02674

ISSN=1664-3224

ABSTRACT=<p>The encapsulated bacteria <italic>Streptococcus pneumoniae, Neisseria meningitis, Haemophilus influenzae</italic>, and <italic>Streptococcus agalactiae</italic> (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 <italic>H. influenzae</italic> and Group B Streptococcus.</p>