Department of Epidemiology, Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan.
Department of Epidemiology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan.
Vaccine. 2024 Aug 30;42(21):126156. doi: 10.1016/j.vaccine.2024.126156. Epub 2024 Jul 31.
Despite the emergence of SARS-CoV-2 variants and waning immunity after initial vaccination, data on antibody kinetics following booster doses, particularly those adapted to Omicron subvariants like XBB.1.5, remain limited. This study assesses the kinetics of anti-spike protein receptor-binding domain (S-RBD) IgG antibody titers post-booster vaccination in a Japanese population during the Omicron variant epidemic.
A prospective cohort study was conducted in Bizen City, Japan, from November 2023 to January 2024. Participants included residents and workers aged ≥18 years, with at least three COVID-19 vaccinations. Antibody levels were measured from venous blood samples. The study analyzed 424 participants and 821 antibody measurements, adjusting for variables such as age, sex, underlying conditions, and prior infection status. Mixed-effects models were employed to describe the kinetics of log-transformed S-RBD antibody titers.
The study found that S-RBD antibody titers declined over time but increased with the number of booster vaccinations, particularly those adapted to Omicron and its subvariant XBB.1.5 (Pfizer-BioNTech Omicron-compatible: 0.156, 95%CI -0.032 to 0.344; Pfizer-BioNTech XBB-compatible: 0.226; 95%CI -0.051 to 0.504; Moderna Omicron-compatible: 0.279, 95%CI 0.012 to 0.546; and Moderna XBB-compatible: 0.338, 95%CI -0.052 to 0.728). Previously infected individuals maintained higher antibody titers, which declined more gradually compared to uninfected individuals (coefficient for interaction with time 0.006; 95%CI 0.001 to 0.011). Sensitivity analyses using Generalized Estimating Equations and interval-censored random intercept model confirmed the robustness of these findings.
The study provides specific data on antibody kinetics post-booster vaccination, including the XBB.1.5-adapted vaccine, in a highly vaccinated Japanese population. The results highlight the importance of considering individual demographics and prior infection history in optimizing vaccination strategies.
尽管出现了 SARS-CoV-2 变体且初次接种疫苗后免疫应答逐渐减弱，但关于加强针接种后抗体动力学的数据，特别是针对像 XBB.1.5 这样的奥密克戎亚变体的加强针，仍然有限。本研究评估了在奥密克戎变体流行期间，日本人群中加强针接种后抗刺突蛋白受体结合域（S-RBD）IgG 抗体滴度的动力学。
本研究于 2023 年 11 月至 2024 年 1 月在日本备前市进行了一项前瞻性队列研究。参与者包括年龄≥18 岁的居民和工作人员，且至少接种过 3 剂 COVID-19 疫苗。通过静脉血样测量抗体水平。该研究共分析了 424 名参与者和 821 次抗体测量结果，同时调整了年龄、性别、基础疾病和既往感染状态等变量。采用混合效应模型描述了对数转换的 S-RBD 抗体滴度的动力学。
研究发现，S-RBD 抗体滴度随时间推移而下降，但随着加强针接种次数的增加而增加，特别是针对奥密克戎及其亚变体 XBB.1.5 的加强针（辉瑞-BioNTech 奥密克戎相容型：0.156，95%CI-0.032 至 0.344；辉瑞-BioNTech XBB 相容型：0.226；95%CI-0.051 至 0.504；莫德纳奥密克戎相容型：0.279，95%CI 0.012 至 0.546；和莫德纳 XBB 相容型：0.338，95%CI-0.052 至 0.728）。既往感染者维持较高的抗体滴度，与未感染者相比，其抗体滴度下降更为缓慢（时间与交互作用的系数 0.006；95%CI 0.001 至 0.011）。使用广义估计方程和区间 censored 随机截距模型的敏感性分析证实了这些发现的稳健性。
本研究在一个高度接种疫苗的日本人群中提供了加强针接种后抗体动力学的具体数据，包括针对 XBB.1.5 的疫苗。结果强调了在优化疫苗接种策略时考虑个体人口统计学特征和既往感染史的重要性。
