Department of Laboratory Medicine, Jiangnan University Medical Center, Wuxi, JS, China.
Wuxi School of Medicine, Jiangnan University, Wuxi, JS, China.
Hum Vaccin Immunother. 2023 Aug 1;19(2):2242217. doi: 10.1080/21645515.2023.2242217.
The durability of antibody responses induced by the three-dose of CoronaVac vaccination, especially against SARS-CoV-2 Omicron subvariants, remains unclear. Here in our study, 160 plasma samples from 32 healthy individuals who received three doses of CoronaVac were longitudinally tracked for a period of 20 months. The results showed that a third homologous dose of CoronaVac efficiently increased the SARS-CoV-2 IgG and neutralizing antibody titers and enhanced neutralization activity against Omicron subvariants. The levels of IgG and neutralizing antibody declined from peak levels but remained detectable in most subjects over the course of the next 10-12 months. However, most of the individuals kept neutralizing titers against ancestral Wuhan-Hu-1, while they lost their neutralizing activities against Omicron B.1.1.529, BA.2, BA.4/BA.5, and BA.2.75.2 subvariants at 10-12 months post the third vaccination. Our results suggest that a fourth dose of vaccine may be necessary for uninfected individuals to confer higher neutralization against emerging Omicron subvariants.
三剂科兴疫苗诱导的抗体反应的持久性，特别是针对 SARS-CoV-2 奥密克戎亚变体，尚不清楚。在我们的研究中，对 32 名接种三剂科兴疫苗的健康个体的 160 份血浆样本进行了长达 20 个月的纵向跟踪。结果表明，第三剂同源科兴疫苗能有效提高 SARS-CoV-2 IgG 和中和抗体滴度，并增强对奥密克戎亚变体的中和活性。在接下来的 10-12 个月内，IgG 和中和抗体水平从峰值下降，但在大多数受试者中仍可检测到。然而，大多数个体对原始的武汉株（Wuhan-Hu-1）保持中和滴度，而对奥密克戎 B.1.1.529、BA.2、BA.4/BA.5 和 BA.2.75.2 亚变体的中和活性在第三剂接种后 10-12 个月丧失。我们的研究结果表明，对于未感染者，第四剂疫苗可能是必要的，以提供更高的针对新出现的奥密克戎亚变体的中和作用。
