Diagnosis and Therapy of Infectious Diseases and Cancer, Oswaldo Cruz Foundation (Fiocruz), Belo Horizonte, Brazil.
Department of Infectious Diseases, College of Veterinary Medicine, University of Georgia, Athens, GA, United States.
Front Immunol. 2022 Jun 9;13:918896. doi: 10.3389/fimmu.2022.918896. eCollection 2022.
Effective and safe vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are critical to controlling the COVID-19 pandemic and will remain the most important tool in limiting the spread of the virus long after the pandemic is over.
We bring pioneering contributions on the maintenance of the immune response over a year on a real-life basis study in 1,587 individuals (18-90 yrs, median 39 yrs; 1,208 female/379 male) who underwent vaccination with two doses of CoronaVac and BNT162b2 booster after 6-months of primary protocol.
Elevated levels of anti-spike IgG antibodies were detected after CoronaVac vaccination, which significantly decreased after 80 days and remained stable until the introduction of the booster dose. Heterologous booster restored antibody titers up to-1·7-fold, changing overall seropositivity to 96%. Titers of neutralising antibodies to the Omicron variant were lower in all timepoints than those against Delta variant. Individuals presenting neutralising antibodies against Omicron also presented the highest titers against Delta and anti-Spike IgG. Cellular immune response measurement pointed out a mixed immune profile with a robust release of chemokines, cytokines, and growth factors on the first month after CoronaVac vaccination followed by a gradual reduction over time and no increase after the booster dose. A stronger interaction between those mediators was noted over time. Prior exposure to the virus leaded to a more robust cellular immune response and a rise in antibody levels 60 days post CoronaVac than in individuals with no previous COVID-19. Both vaccines were safe and well tolerated among individuals.
Our data approach the effectiveness of CoronaVac association with BNT162b2 from the clinical and biological perspectives, aspects that have important implications for informing decisions about vaccine boosters.
Fiocruz, Brazil.
有效且安全的严重急性呼吸综合征冠状病毒 2 (SARS-CoV-2) 疫苗对于控制 COVID-19 大流行至关重要，并且在大流行结束后很长一段时间内，它们仍将是限制病毒传播的最重要工具。
我们在一项基于真实情况的研究中，对 1587 名（18-90 岁，中位数 39 岁；1208 名女性/379 名男性）个体的免疫反应维持情况进行了开创性的研究，这些个体在完成两剂科兴和国药疫苗接种 6 个月后接受了 CoronaVac 和 BNT162b2 加强针接种。
接种 CoronaVac 后可检测到抗刺突 IgG 抗体水平升高，80 天后显著下降，直到加强针接种后才保持稳定。异源加强针将抗体滴度恢复至-1.7 倍，总体血清阳性率提高至 96%。在所有时间点，针对奥密克戎变异株的中和抗体滴度均低于针对德尔塔变异株的中和抗体滴度。针对奥密克戎变异株具有中和抗体的个体也表现出针对德尔塔和抗刺突 IgG 的最高滴度。细胞免疫反应测量显示出一种混合免疫谱，在接种 CoronaVac 后第一个月内大量释放趋化因子、细胞因子和生长因子，随着时间的推移逐渐减少，加强针接种后没有增加。随着时间的推移，这些介质之间的相互作用更强。与无既往 COVID-19 史的个体相比，先前感染过该病毒的个体在接种 CoronaVac 后 60 天内表现出更强的细胞免疫反应和抗体水平升高。两种疫苗在个体中均安全且耐受良好。
我们的数据从临床和生物学角度探讨了 CoronaVac 与 BNT162b2 联合使用的有效性，这些方面对于疫苗加强针的决策具有重要意义。
Fiocruz，巴西。
