Joshi Devyani, Nyhoff Lindsay E, Zarnitsyna Veronika I, Moreno Alberto, Manning Kelly, Linderman Susanne, Burrell Allison R, Stephens Kathy, Norwood Carson, Mantus Grace, Ahmed Rafi, Anderson Evan J, Staat Mary A, Suthar Mehul S, Wrammert Jens
Division of Infectious Diseases, Department of Pediatrics, School of Medicine, Emory University, Atlanta, GA, USA.
Emory Vaccine Center, Emory University School of Medicine, Atlanta, GA, USA.
iScience. 2023 Sep 20;26(10):107967. doi: 10.1016/j.isci.2023.107967. eCollection 2023 Oct 20.
As SARS-CoV-2 becomes endemic, it is critical to understand immunity following early-life infection. We evaluated humoral responses to SARS-CoV-2 in 23 infants/young children. Antibody responses to SARS-CoV-2 spike antigens peaked approximately 30 days after infection and were maintained up to 500 days with little apparent decay. While the magnitude of humoral responses was similar to an adult cohort recovered from mild/moderate COVID-19, both binding and neutralization titers to WT SARS-CoV-2 were more durable in infants/young children, with spike and RBD IgG antibody half-life nearly 4X as long as in adults. IgG subtype analysis revealed that while IgG1 formed the majority of the response in both groups, IgG3 was more common in adults and IgG2 in infants/young children. These findings raise important questions regarding differential regulation of humoral immunity in infants/young children and adults and could have broad implications for the timing of vaccination and booster strategies in this age group.
随着严重急性呼吸综合征冠状病毒2（SARS-CoV-2）成为地方性流行病毒，了解早期感染后的免疫情况至关重要。我们评估了23名婴幼儿对SARS-CoV-2的体液免疫反应。对SARS-CoV-2刺突抗原的抗体反应在感染后约30天达到峰值，并维持长达500天，几乎没有明显衰减。虽然体液免疫反应的强度与从轻度/中度新冠肺炎中康复的成人队列相似，但婴幼儿对野生型SARS-CoV-2的结合和中和滴度更持久，刺突和受体结合域（RBD）IgG抗体半衰期几乎是成人的4倍。IgG亚型分析显示，虽然两组中IgG1在反应中占多数，但IgG3在成人中更常见，而IgG2在婴幼儿中更常见。这些发现提出了关于婴幼儿和成人体液免疫差异调节的重要问题，并可能对该年龄组的疫苗接种时间和加强免疫策略产生广泛影响。
