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Covid19 one year on. How Scientific endeavours have identified the SARS-CoV-2 protein, developed a vaccine & supported the medical profession during the pandemic.

By March 24, 2021 No Comments

On the 23rd March 2021, the UK took a moment to reflect on the effects of the past 12 months.

On the 23rd March 2020, Boris Johnson announced the first UK Covid19 lockdown. We had all seen it coming, we had watched Covid ravage Europe & we knew it was on the way; but non of us could have foreseen the impact it would have had on us all.

Yesterday, 23rd March 2021, the UK mourned the loss of life from the Coronavirus, observing a minutes silence & in many counties at 8pm, people came out on their doorsteps with candles or torches to honour those who have lost their lives to this deadly disease.

So very much has changed & so very much is yet to change. However, the UK Covid vaccine rollout has thus far vaccinated nearly 30 million people, with some 2.1 million people having already received their second dose. Therefore, there is hope, there are chinks of light at the end of what seems like a very long tunnel.

With this in mind, we take a moment to look back on some of the Scientific advances made during the pandemic.

Cryo-EM – How Cryogenics helped identify the SARS-CoV-2 protein.

Cryo-EM is a technique pioneered by Jacques Dubochet of the University of Lausanne in Switzerland, Joachim Frank of Columbia University in New York City, US, & Richard Henderson of the MRC Laboratory of Molecular Biology in Cambridge, UK, for which they shared the 2017 Nobel Prize for Chemistry (1)

Cryo-EM is essentially is a form of transmission electron microscopy which allows for a specimen of interest to be viewed at cryogenic temperatures (1)

Cryo-EM uses samples which are usually frozen (frozen-hydrated) to preserve a specimen’s structure. A very thin slide of the specimen can be rapidly plunged into a liquid ethane bath (2) to vitrify the sample & which is then imaged by the electron microscope with low doses of electrons to minimize radiation damage (2)

The benefits of using cryo-EM technologies when imaging molecular biological samples, is the lack of need for dyes & crystallization to ensure a perfect image is obtained. In the case of the SARS-CoV-2, thousands of images were taken using this technique, which then allowed a 3D printed image to be produced, identifying the protein spike we now know to cause such effective damage by the virus (3) These images were gathered in less than 24 hours & made the understanding of the virus structure globally understood.

With cryo-EM having only been recognised & gained broader adoption about eight years ago, advances in the electron detectors, software, productivity, and other important factors now allow researchers to resolve relevant biological samples at higher resolution quicker than ever before.

With the use of the cryo-EM technology, the imagining sequence took a matter of hours, whereby without the use of the cryo-EM, it could have taken months even years to collate the valuable data. (4)

In the case of the SARS-CoV-2, Daniel Wrapp & Nianshuang Wang, University of Texas at Austin, US, & their colleagues were able to obtain the structure of an outer “spike” protein of SARS-CoV-2 which has helped the scientific community to understand how the virus forces its way into host cells. From harvesting the protein to submitting a paper to the journal Science on 10th February 2020, the process took just 12 days. (2)

The speed with which the medical & scientific communities worked to identify & recognise the structure of SARS-CoV-2 was astonishing & could not have been realised if it had not been for the use of the cryo-electron microscopy data.

ThermoFisher Scientific identifies key dates in its publication ‘Cryo-EM Used in Novel Coronavirus Research to Support Vaccine, Treatment Development’ published 12th March 2020 (4)

Cryogenics have played another important role in the pandemic, that of providing medical oxygen supplies to critical care patients.

Having ascertained very quickly that the 15% of COVID19 patients in China with severe illness were in need of mechanical ventilation & lung support technologies; the need for increased numbers of ventilators & an increased availability of medical O2 was evident from very early on.

The WHO cited that the need for severely ill COVID19 patient’s to be mechanically ventilated would see that ‘COVID-19 treatment health-care facilities should be equipped with pulse oximeters, functioning oxygen systems including single-use oxygen delivery interfaces’ (5)

Cryogenically produced liquid oxygen, cannot be produced on-site at medical facilities & is therefore manufactured at source. According to the WHO ‘Although an economical option in some settings, the use of liquid oxygen relies on external supply chain mechanisms and needs a bit more caution with respect to transport and storage due to the risks associated with higher pressures’ (5)

Around the world, gas companies increased their delivery of O2 & in many cases have been installing on site liquid oxygen tanks at hospitals.

Air Liquide & Linde, two international suppliers of liquid oxygen, were seeing a between five to tenfold increase in demand for medical O2. In response to the increased demand, Nippon Gases’ subsidiary, Oximesa, shifted to a 24-hour production schedule in Spain. (6)

BOC were instrumental in providing oxygen tanks & four kilometers of piping at the EXCEL Nightingale Hospital in London, freeing up 3000 cylinders in the process.

Respirators & Ventilators rapid roll out.

The need for increased manufacture & for a rapid production of ventilators worldwide, saw many international manufacturers turn their hands to rising to the challenge.

On the 20th March 2020, CERN’s Director General set up a task force to call on the 18,000 members worldwide, to pool their collective specialisms to support the COVID19 pandemic effort. Member states of CERN were encouraged to propose how the collective technological competencies of CERN could be best used to help support the COVID19 pandemic efforts.

According to the ‘CERN Against COVID-19’ website (2020), one of the key areas they turned their knowledge pool too, was the design & manufacture of PPE using 3D printing technologies & the manufacture of 1 tonne of medical grade hand gel, manufactured from chemical components already in their labs. (7)

Furthermore, the need for an easily available ventilator, reliant on components already available & which complied with the strict hospital standards; was tackled by Jan Buytaert – Physicist LHCb Collaboration.

Jan Buytaert designed & built a buffer using readily available components, designed to support mechanical ventilation for critical care patients. The buffer uses a series of regulators, a buffer which maintains the oxygen supply momentarily & an inhale valve which produces approximately ½ litre of air per breath. (7)

Professor Sarah Gilbert – Saïd Professorship of Vaccinology – Oxford Astrazeneca vaccine.

In 2014, Professor Gilbert led the first trial of an Ebola vaccine & when the Mers – Middle East respiratory syndrome – virus struck, she travelled to Saudi Arabia to try to develop a vaccine for this form of coronavirus.

The second trial of that vaccine was just beginning when, in early 2020, Covid-19 emerged in China & Professor Gilbert realised she might be able to use the same approach. (8)

It took a few weeks to create a vaccine which worked against Covid in the lab. Then the first batch went into manufacture by early April & the rigorous testing regime expanded.

As we came into 2021, the now commonly known Oxford Astrazeneca vaccine has been a considerable part of the UK vaccine roll out & has been approved & recommended by the World Health Organisation (WHO).

Written by Katy-Jane Mason for & on behalf of Dolphin N2

  1. https://www.microscopemaster.com/cryo-electron-microscopy.html
  2. https://physicsworld.com/a/covid-19-how-physics-is-helping-the-fight-against-the-pandemic/
  3. https://commonfund.nih.gov/CryoEM
  4. https://www.thermofisher.com/blog/microscopy/cryo-em-used-in-novel-coronavirus-research-to-support-vaccine-treatment-development/
  5. WHO reference number: WHO/2019-nCoV/Oxygen_sources/2020.1 04.04.2020
  6. https://cryogenicsociety.org/37535/news/how_industrial_gas_firms_are_meeting_medical_oxygen_demand_for_covid-19_patients/
  7. https://againstcovid19.cern/
  8. https://www.bbc.co.uk/news/uk-55043551