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Boston University researchers create new COVID strain 6park.com 6park.com Coronavirus
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Caitlyn Shelton 6park.com
Posted: Oct 17, 2022 / 09:06 PM CDT
| Updated: Oct 17, 2022 / 09:06 PM CDT 6park.com
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(NewsNation) — Researchers at Boston University created a new strain of COVID-19 in efforts to examine the role of a specific protein associated with the omicron variant. Their virus, generated in a biosafety level four lab, caused rapidly deteriorating, severe disease with a mortality rate of 80% in the mice it was tested on during the research process. 6park.com
The omicron variant is highly transmissible, even in those who have been fully vaccinated. Omicron’s spike or “S” protein has an unusually large amount of mutations and is considered by researchers to be the major driver of traits specific to omicron. 6park.com
With that in mind, the Department of Biochemistry at the Boston University School of Medicine decided to examine the role of spike or the “S” protein in what causes omicron and how it impacts the immune response to the virus. 6park.com
6park.com 6park.com 6park.com“This study to better understand the role of spike proteins in the omicron variant was conducted by researchers from the BU School of Medicine and various other departments at BU and other schools,” Boston University shared in a statement. 6park.com
Researchers produced fusion proteins of COVID and encoded the “S” gene of Omicron into ancestral COVID. They compared what they generated to the omicron variant that is circulating through communities. 6park.com
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6park.comDr. Monica Gandhi, professor of medicine and infectious diseases at UCSF, says as far as omicron goes, there is something less virulent and more transmissible about it. 6park.com
“The most virulent strains of COVID-19 were the original Wuhan, Alpha and Delta. They wanted to see if it was the spike protein mutations that made it less virulent by sticking the spike protein of COVID-19 Omicron onto the ancestral strain,” Dr. Gandhi explained in an interview on NewsNation’s “Rush Hour.” 6park.com
Using mice for testing purposes, researchers found that regular omicron typically causes mild, non-fatal infection. Mice with the omicron S-carrying virus experienced rapidly deteriorating, severe disease with a mortality rate of 80 percent. 6park.com
“In K18-hACE2 mice, Omi-S contrasts with non-fatal Omicron and causes a severe disease leading to around 80% mortality. This suggests that mutations outside of spike are major determinants of the attenuated pathogenicity of Omicron in K18-hACE2 mice,” the study said. 6park.com
The researchers focused on the “S” protein due to mutations. They say omicron differs from the initial coronavirus strain by 59 amino acids. Out of those, 37 of the changes are in the “S” protein. They say this could be “raising the possibility that S is at the heart of Omicron’s pathogenic and antigenic behavior.” 6park.com
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6park.comWhile the new virus was created in a biosafety level four lab, Dr. Gandhi said when it comes to biosafety procedures and viruses, scientists must be extremely careful. 6park.com
6park.com 6park.com 6park.com“I’m a little bit worried that this was created. I think, point proven, let’s destroy this now,” Dr. Gandhi said, later adding: “In this case, prove something then destroy it. Put out the results and move on. We don’t want to keep on moving around with viruses.” 6park.com
Through more testing, the researchers at Boston University learned that the “S” protein is not the primary determinant and only partly responsible for Omicron’s cause of infection. Still, researchers say further studies are needed to identify mutations outside of the “S” protein and see how they act. 6park.com
The study was released on the BioRxiv website, which is a preprint server for biology. The site houses studies that may not have been peer reviewed or finalized by authors.
波士顿大学研发出极度高致死型新冠病毒分支 ，该毒株的传染性是奥密克戎的五倍，致死率（小鼠试验）达到了80%；
6park.com波士顿大学的研究人员表示，他们开发出了一种新的新冠毒株，将目前占主导地位的奥密克戎（Omicron）变种和2019年底在中国首次发现的原始毒株进行结合，经过一系列类似的实验后，该毒株的传染性是奥密克戎的五倍，致死率（小鼠试验）达到了80%； 6park.com
在这项未经同行评审的新研究中，来自波士顿和佛罗里达州的一组研究人员提取了奥密克戎变种的刺突蛋白，附加到疫情刚开始时的原始新冠毒株上，将其命名为奥密克戎 S（Omicron S）。
研究人员在实验鼠身上对这种杂交毒株进行了实验，并与奥密克戎毒株进行了对比。他们在论文中写道：“在K18-hACE2小鼠中，虽然奥密克戎会导致轻度、非致命的感染，但奥密克戎 S 的病毒会导致严重的疾病，而整体试验中其中八成以上的小鼠短期内就死亡了”对比在只接触奥密克戎毒株的组里，这些试验老鼠大都活了下来，并且只出现了相对“轻微”症状。 6park.com研究人员表示，这表明虽然刺突蛋白负责传染性逃逸疫苗，但其结构其他部分的变化决定了它的致命性。刺突蛋白是一种结合并侵入人体细胞的独特结构，并指示健康细胞产生病毒的拷贝。它会随着时间的推移进化。奥密克戎的刺突蛋白上有数十个突变，使其成为具有传染性并能逃避免疫的新冠毒株。不过，研究人员指出，如果奥密克戎 S 要感染人类，致命性相对实验老鼠会更低，但也是史无前例的。他们解释道，小鼠和人类的免疫系统差异很大，目前没有小鼠模型能够复制人类新冠的所有方面。另外，研究用的是一个特定品种的老鼠，不是与人类更相似的其他老鼠，这种老鼠是专门为观察严重的新冠症状而开发的，因此非常容易感染。话虽如此，研究人员也承认，他们用奥密克戎 S 变体感染人类肺细胞时，他们发现它的传染性是奥密克戎的五倍。 6park.com波士顿大学的国家新兴传染病实验室是美国授权处理最危险病原体的13个BSL-4实验室之一。此前，由于担心可能导致无意中造成疫情，在2014年至2017年期间美国曾停止对病毒进行功能性改造。直到2017年，美国国立卫生研究院开始恢复允许使用政府资金进行功能研究。 6park.com该研究的发表立即引起了国际社会大量的关注和谴责。以色列政府首席科学家什穆埃尔·夏皮拉教授说：“这应该被完全禁止，这是在玩火。”新泽西罗格斯大学的化学家理查德·埃布赖特博士说：“如果我们要避免下一次实验室引发的大流行，就必须对潜在大流行病原体的增强研究加强监督。”英国东英吉利大学传染病专家保罗·亨特博士10月17日说，他担心实验室能够生产什么，“问题是你将使用这种实验室来做什么。如果它们用于医疗目的，那么您需要它们。但我不认为每个国家都需要 BSL-4”。他还说：“如果他们开始对具有进攻性军事影响的研究有双重目的，那就值得担心了”。 6park.com
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