Alam Mohammad Shah
Department of Anatomy and Histology, Bangabandhu Sheikh Mujibur Rahman Agricultural University, Gazipur 1706, Bangladesh.
Heliyon. 2023 Feb;9(2):e13285. doi: 10.1016/j.heliyon.2023.e13285. Epub 2023 Jan 31.
The Omicron, the latest variant of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), was first detected in November 2021 in Botswana, South Africa. Compared to other variants of SARS-CoV-2, the Omicron is the most highly mutated, with 50 mutations throughout the genome, most of which are in the spike (S) protein. These mutations may help the Omicron to evade host immunity against the vaccine. Epidemiological studies suggest that Omicron is highly infectious and spreads rapidly, but causes significantly less severe disease than the wild-type strain and the other variants of SARS-CoV-2. With the increased transmissibility and a higher rate of re-infection, Omicron has now become a dominant variant worldwide and is predicted to be able to evade vaccine-induced immunity. Several clinical studies using plasma samples from individuals receiving two doses of US Food and Drugs Administration (FDA)-approved COVID-19 vaccines have shown reduced humoral immune response against Omicron infection, but T cell-mediated immunity was well preserved. In fact, T cell-mediated immunity protects against severe disease, and thus the disease caused by Omicron remains mild. In this review, I surveyed the current status of Omicron variant mutations and mechanisms of immune response in the context of immune escape from COVID-19 vaccines. I also discuss the potential implications of therapeutic opportunities that are independent of SARS-CoV-2 variants, including Omicron. A better understanding of vaccine-induced immune responses and variant-independent therapeutic interventions that include potent antiviral, antioxidant, and anti-cytokine activities may pave the way to reducing Omicron-related COVID-19 complications, severity, and mortality. Collectively, these insights point to potential research gaps and will aid in the development of new-generation COVID-19 vaccines and antiviral drugs to combat Omicron, its sublineages, or upcoming new variants of SARS-CoV-2.
奥密克戎是严重急性呼吸综合征冠状病毒2（SARS-CoV-2）的最新变种，于2021年11月在南非博茨瓦纳首次被发现。与SARS-CoV-2的其他变种相比，奥密克戎的变异程度最高，其整个基因组有50个突变，其中大部分位于刺突（S）蛋白上。这些突变可能有助于奥密克戎逃避免疫系统对疫苗的免疫反应。流行病学研究表明，奥密克戎具有高度传染性且传播迅速，但与野生型毒株及SARS-CoV-2的其他变种相比，其导致的疾病严重程度明显较低。随着传播性的增加和再感染率的上升，奥密克戎现已成为全球主要变种，并预计能够逃避免疫疫苗诱导的免疫。多项使用接受两剂美国食品药品监督管理局（FDA）批准的新冠疫苗的个体血浆样本进行的临床研究表明，针对奥密克戎感染的体液免疫反应有所降低，但T细胞介导的免疫反应仍得到良好保留。事实上，T细胞介导的免疫反应可预防严重疾病，因此奥密克戎导致的疾病仍然较轻。在本综述中，我在新冠疫苗免疫逃逸的背景下，审视了奥密克戎变种突变的现状及其免疫反应机制。我还讨论了独立于SARS-CoV-2变种（包括奥密克戎）的治疗机会的潜在影响。更好地理解疫苗诱导的免疫反应以及包括强效抗病毒、抗氧化和抗细胞因子活性在内的与变种无关的治疗干预措施，可能为减少与奥密克戎相关的新冠并发症、严重程度和死亡率铺平道路。总体而言，这些见解指出了潜在的研究空白，并将有助于开发新一代新冠疫苗和抗病毒药物，以对抗奥密克戎及其亚系，或即将出现的SARS-CoV-2新变种。
