Article

Levy, O. Innate immunity of the newborn: basic mechanisms and clinical correlates. Nat Rev Immunol 7, 379-390

Department of Medicine, Division of Infectious Diseases, Children's Hospital Boston and Harvard Medical School, Boston, MA 02115, USA.
Nature reviews. Immunology (Impact Factor: 34.99). 06/2007; 7(5):379-90. DOI: 10.1038/nri2075
Source: PubMed

ABSTRACT

The fetus and newborn face a complex set of immunological demands, including protection against infection, avoidance of harmful inflammatory immune responses that can lead to pre-term delivery, and balancing the transition from a sterile intra-uterine environment to a world that is rich in foreign antigens. These demands shape a distinct neonatal innate immune system that is biased against the production of pro-inflammatory cytokines. This bias renders newborns at risk of infection and impairs responses to many vaccines. This Review describes innate immunity in newborns and discusses how this knowledge might be used to prevent and treat infection in this vulnerable population.

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    • "In higher vertebrates, it has been reported that soon after birth more than 50% of all human neonates develop a prominent but transitory rash caused by reaction of the immature skin to commensal flora. Emerging evidence indicates that such bacterial skin interaction may activate the release of IL-6 by the host, which probably contributes to ameliorating the rash, exemplifying how important an appropriate innate immune response against a particular stimulus is required upon maturation of the neonatal immune system (Levy, 2007). These evidences clearly illustrate part of the related mechanism. "
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    • "This age-dependence is due to two additive phenomena. First, age has a 'biological' effect as host behaviors and immune defenses may evolve with age (e.g., (Anderson et al., 1992; Gasparoni et al., 2003; Levy, 2007; Bogaards et al., 2010)). Second, older individuals are more likely to be seropositive because of a longer exposure time, mechanically creating a cumulative effect of age. "
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    • "The maturation of the immune system is complex because the multiple component have different ontogenetic trajectories and because they are influenced by both internal factors [e.g., innate immunity; (Cuadros & Navascues, 1998; Levy, 2007)] and external factors [e.g., transmission to the infant via the mother (Newburg & Walker, 2007; Paramasivam, Michie, Opara, & Jewell, 2006)]. Here, we briefly summarize some of those factors as they change during early development. "
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