Department of Biomedicine, Neurosciences and Advanced Diagnostics, Institute of Clinical Biochemistry, Clinical Molecular Medicine and Clinical Laboratory Medicine, University of Palermo, 90127, Palermo, Italy.
Department of Laboratory Medicine, Azienda Ospedaliera Universitaria Policlinico "P. Giaccone", 90127, Palermo, Italy.
Sci Rep. 2022 May 23;12(1):8679. doi: 10.1038/s41598-022-12750-z.
Immunosurveillance by evaluating anti-spike protein receptor-binding domain (S-RBD) antibodies represents a useful tool to estimate the long immunity against Severe Acute Respiratory Syndrome CoronaVirus 2 (SARS-CoV-2) infection. The aim of this study was to evaluate the kinetics of antibody response in vaccine recipients. We measured anti-S-RBD IgG levels by indirect chemiluminescence immunoassay on Maglumi 800 (SNIBE, California) in 1013 healthy individuals naïve to SARS-CoV2 infection after two and three COVID-19 vaccine doses. We found that anti-S-RBD IgG levels are higher in females than males. Antibody levels gradually decrease to a steady state after four months since the peak, and the decay is independent of age, sex, vaccine doses, and baseline antibodies titer. The third dose induces a high anti-S-RBD IgG reactivity in individuals with previous high responses and triggers a moderate-high anti-S-RBD IgG reactivity. The assessment of anti-S-RBD IgG levels is essential for monitoring long-term antibody response. A third SARS-CoV-2 vaccine dose is associated with a significant immunological response. Thus, our results support the efficacy of the vaccine programs and the usefulness of the third dose.
免疫监测通过评估抗刺突蛋白受体结合域（S-RBD）抗体，是评估对严重急性呼吸综合征冠状病毒 2（SARS-CoV-2）感染的长期免疫的有用工具。本研究旨在评估疫苗接种者的抗体反应动力学。我们使用间接化学发光免疫分析法在 Maglumi 800（SNIBE，加利福尼亚）上测量了 1013 名未感染 SARS-CoV2 的健康个体在接受两剂和三剂 COVID-19 疫苗后的抗 S-RBD IgG 水平。我们发现女性的抗 S-RBD IgG 水平高于男性。抗体水平在峰值后四个月逐渐降至稳定状态，其衰减与年龄、性别、疫苗剂量和基线抗体滴度无关。第三剂在先前高反应个体中诱导高抗 S-RBD IgG 反应，并引发中高抗 S-RBD IgG 反应。评估抗 S-RBD IgG 水平对于监测长期抗体反应至关重要。第三剂 SARS-CoV-2 疫苗与显著的免疫反应相关。因此，我们的结果支持疫苗计划的有效性和第三剂的有用性。
