Department of Surgery, University of Florida, Gainesville, FL, USA.
Am J Perinatol. 2013 Feb;30(2):105-12. doi: 10.1055/s-0032-1333412. Epub 2013 Jan 7.
Newborns are at increased risk of infection due to genetic, epigenetic, and environmental factors. Herein we examine the roles of the neonatal innate immune system in host defense against bacterial and viral infections. Full-term newborns express a distinct innate immune system biased toward T(H)2-/T(H)17-polarizing and anti-inflammatory cytokine production with relative impairment in T(H)1-polarizing cytokine production that leaves them particularly vulnerable to infection with intracellular pathogens. In addition to these distinct features, preterm newborns also have fragile skin, impaired T(H)17-polarizing cytokine production, and deficient expression of complement and of antimicrobial proteins and peptides (APPs) that likely contribute to susceptibility to pyogenic bacteria. Ongoing research is identifying APPs, including bacterial/permeability-increasing protein and lactoferrin, as well as pattern recognition receptor agonists that may serve to enhance protective newborn and infant immune responses as stand-alone immune response modifiers or vaccine adjuvants.
新生儿由于遗传、表观遗传和环境因素而面临更高的感染风险。在此，我们研究了新生儿固有免疫系统在抵抗细菌和病毒感染中的作用。足月新生儿表达了一种独特的固有免疫系统，偏向于 T(H)2/T(H)17 极化和抗炎细胞因子的产生，而 T(H)1 极化细胞因子的产生相对受损，这使他们特别容易受到细胞内病原体的感染。除了这些独特的特征外，早产儿还具有脆弱的皮肤、T(H)17 极化细胞因子产生受损以及补体和抗菌蛋白和肽（APPs）表达不足，这可能导致对化脓性细菌的易感性。正在进行的研究正在确定 APPs，包括细菌/通透性增加蛋白和乳铁蛋白，以及模式识别受体激动剂，它们可能作为独立的免疫调节剂或疫苗佐剂，增强新生儿和婴儿的保护性免疫反应。
