Department of Biology, College of Sciences, University of Ha'il, Ha'il, Saudi Arabia.
Department of Chemistry, College of Sciences, University of Ha'il, Ha'il, Saudi Arabia.
Front Public Health. 2022 Jun 9;10:874741. doi: 10.3389/fpubh.2022.874741. eCollection 2022.
Two years into the pandemic, yet the threat of new SARS-CoV-2 variants continues to loom large. Sustained efforts are required to fully understand the infection in asymptomatic individuals and those with complications. Identification, containment, care, and preventative strategies rely on understanding the varied humoral immune responses.
An in-house ELISA was developed and standardized to screen for serum IgG antibodies against the SARS-CoV-2 S1-RBD protein as an antigen. This study aims to investigate the seroprevalence of serum antibodies against S1-RBD antigen in pre-pandemic ( = 120) and during the early pandemic period ( = 120) in subjects from the Hail region, KSA and to correlate it with clinical and demographic factors.
Samples collected from both male ( = 60) and female ( = 60) subjects during the pandemic in the age groups of 20-40 (0.31 ± 0.029 and 0.29 ± 0.024, respectively) and 41-60 years (0.35 ± 0.026 and 0.30 ± 0.025, respectively) showed significantly higher levels of serum antibodies against S-RBD antigen than the age-matched pre-pandemic samples [male ( = 60) and female ( = 60)]. Pandemic subjects exhibited significantly ( < 0.01) higher inhibition (80-88%) than age-matched pre-pandemic subjects (32-39%). Antibodies against S1-RBD antigen were detected in approximately 10% of the total pre-pandemic population (males and females). However, subjects > 60 years did not show antibodies.
Antibody levels increased in samples collected during the pandemic, even though these subjects were not clinically COVID-19 positive. A small number of pre-pandemic subjects showed serum antibodies, suggesting prior exposure to other coronaviruses in the region. With dwindling neutralizing antibody levels and reduced vaccine efficacy against newer variants, it remains crucial to develop better assays for surveillance, management, and future research.
大流行进入第二年，新的 SARS-CoV-2 变体的威胁仍然迫在眉睫。需要持续努力才能充分了解无症状个体和有并发症个体的感染情况。识别、遏制、护理和预防策略依赖于对不同体液免疫反应的理解。
开发并标准化了一种内部 ELISA，以筛选针对 SARS-CoV-2 S1-RBD 蛋白作为抗原的血清 IgG 抗体。本研究旨在调查沙特阿拉伯海地区大流行前（=120）和大流行早期（=120）人群血清中针对 S1-RBD 抗原的抗体血清阳性率，并将其与临床和人口统计学因素相关联。
在大流行期间，从男性（=60）和女性（=60）受试者中收集的样本，年龄组为 20-40 岁（分别为 0.31±0.029 和 0.29±0.024）和 41-60 岁（分别为 0.35±0.026 和 0.30±0.025），血清中针对 S-RBD 抗原的抗体水平明显高于年龄匹配的大流行前样本[男性（=60）和女性（=60）]。大流行组的抑制率（80-88%）明显高于年龄匹配的大流行前组（32-39%）（<0.01）。在总大流行前人群（男性和女性）中，约有 10%检测到针对 S1-RBD 抗原的抗体。然而，>60 岁的受试者没有检测到抗体。
尽管这些受试者在临床上并非 COVID-19 阳性，但在大流行期间采集的样本中抗体水平增加。少数大流行前的受试者显示出血清抗体，表明该地区先前曾接触过其他冠状病毒。由于针对新型变体的中和抗体水平下降和疫苗效力降低，开发更好的监测、管理和未来研究用的检测方法仍然至关重要。
