Paediatric Endocrinolgy, University Children's Hospital, Hoppe-Seyler-Str. 1, 72076 Tuebingen, Germany.
Mediagnost Gesellschaft für Forschung und Herstellung von Diagnostika GmbH, Aspenhaustr. 25, 72770 Reutlingen, Germany.
Viruses. 2020 Nov 27;12(12):1357. doi: 10.3390/v12121357.
The relationship between the nasopharyngeal virus load, IgA and IgG antibodies to both the S1-RBD-protein and the N-protein, as well as the neutralizing activity (NAbs) against SARS-CoV-2 in the blood of moderately afflicted COVID-19 patients, needs further longitudinal investigation. Several new serological methods to examine these parameters were developed, validated and applied in three patients of a family which underwent an ambulatory course of COVID-19 for six months. The virus load had almost completely disappeared after about four weeks. Serum IgA levels to the S1-RBD-protein and, to a lesser extent, to the N-protein, peaked about three weeks after clinical disease onset but declined soon thereafter. IgG levels rose continuously, reaching a plateau at approximately six weeks, and stayed elevated over the observation period. Virus-neutralizing activity reached a peak about 4 weeks after disease onset but dropped slowly. The longitudinal associations of virus neutralization and the serological immune response suggest immunity in patients even after a mild clinical course of COVID-19.
中度感染 COVID-19 患者血液中的鼻咽病毒载量、针对 S1-RBD 蛋白和 N 蛋白的 IgA 和 IgG 抗体以及针对 SARS-CoV-2 的中和抗体（NAbs）之间的关系需要进一步进行纵向研究。为此，开发、验证并应用了几种新的血清学方法，以检查这几个参数，这些方法在经历了六个月门诊 COVID-19 病程的一个家庭中的三个患者中进行了应用。大约四周后，病毒载量几乎完全消失。针对 S1-RBD 蛋白的血清 IgA 水平，以及在较小程度上针对 N 蛋白的 IgA 水平，在临床发病后约三周达到峰值，但此后很快下降。IgG 水平持续上升，在大约六周时达到平台期，并在观察期间保持升高。病毒中和活性在发病后约 4 周达到峰值，但下降缓慢。病毒中和与血清免疫反应的纵向关联表明，即使在 COVID-19 轻度临床病程后，患者仍具有免疫力。
