JCI Insight. 2020 Dec 17;5(24):141655. doi: 10.1172/jci.insight.141655.
Individuals younger than 6 months of age are at significant risk from influenza virus infection; however, there is currently no vaccine approved for this age group. Influenza virus neuraminidase (NA) has emerged as a potential additional target for vaccine strategies. In this study, we sought to understand the ability of newborns to mount an antibody response to NA. Here we employed a nonhuman primate model, given the similarities to humans in immune system and development. We measured antibody to NA following infection with an H1N1 virus or following vaccination and challenge. Administration of an inactivated virus vaccine was not capable of eliciting detectable NA-specific antibody, even in the presence of adjuvants previously shown to increase total virus-specific IgG. However, both naive and vaccinated newborns generated a NA-specific antibody response following virus infection. Interestingly, the presence of the vaccine-induced response did not prevent generation of systemic antibody to NA following challenge, although the respiratory response was reduced in a significant portion of newborns. These findings are the first, to our knowledge, to evaluate the newborn response to the influenza NA protein as well as the impact of previous vaccination on generation of these antibodies following virus infection.
年龄小于 6 个月的个体感染流感病毒的风险很大；然而，目前尚无针对该年龄组的疫苗获得批准。流感病毒神经氨酸酶 (NA) 已成为疫苗策略的潜在新目标。在这项研究中，我们试图了解新生儿对 NA 产生抗体反应的能力。由于在免疫系统和发育方面与人类具有相似性，我们采用了非人类灵长类动物模型。我们在感染 H1N1 病毒或接种疫苗和挑战后测量了针对 NA 的抗体。即使使用了先前显示可增加总病毒特异性 IgG 的佐剂，灭活病毒疫苗的给药也不能引起可检测到的 NA 特异性抗体。然而，无论是未接种疫苗的新生儿还是已接种疫苗的新生儿，在感染病毒后均产生了 NA 特异性抗体反应。有趣的是，疫苗诱导的反应的存在并没有阻止在挑战后产生针对 NA 的全身性抗体，尽管在很大一部分新生儿中呼吸道反应减少了。这些发现是我们首次评估新生儿对流感 NA 蛋白的反应，以及先前接种疫苗对感染病毒后产生这些抗体的影响。
