Reading scientific papers and journals may seem like a daunting thing, what with the big walls of text and scientific jargon. But don’t be put off – it’s not as scary as it seems! Let’s break down some scientific papers, shall we?
Please note that the material below is borrowed from official sources and I do not lay claim to any of it. Also, the explanations below are merely my own views and interpretations and should not be taken in lieu of professional medical opinion and consultation.
Below are excerpts from a paper published by a group in Beijing on their methods of isolating and inactivating their chosen strain of the Covid-19 virus. For the actual paper, please go to this Science journal page.
Firstly, every scientific paper begins with an Abstract section. This Abstract is a convenient summary of the entire paper.
Imagine you’re reading a novel, and at the start of the book is a full synopsis of the novel you are about to read! So now you know what the whole novel’s story is about, and you only need to read the actual novel if you want the nitty-gritty, raunchy details.
So this paper is about how this group of biotech scientists in Beijing, China isolated a particular strain of the Covid-19 virus, and proceeded to inactivate and replicate it to test whether it produced an immune response in live animals (mice and macaques).
Firstly, they explain how they selected the strain of the virus (because like any organism, there are variants and mutations which creates different versions of the organism). They chose one of the more commonly occurring strains of the Covid-19 virus, CN2.
They then went about inactivating the virus so that it would still appear to be a live virus that would generate an immune response in the host, but not actually cause the illness and have the full detrimental effects that a regular Covid-19 virus would.
For the viral inactivation, the group used a substance called β-Propiolactone. This substance is an organic compound of the lactone family. It is described as a colorless liquid with a slightly sweet odour, and is highly soluble in water and miscible with ethanol, acetone, diethyl ether and chloroform.
Here is what the compound looks like:
β-Propiolactone is an excellent sterilizing and sporicidal agent, which means it is great at killing micro-organisms like bacteria and fungi.
However, it has been found to cause cancer, so although it was once widely produced as an intermediate in the production of other chemical compounds like acrylic acid and its esters, these days it is not heavily produced.
After they used this chemical to power down the Covid-19 virus, they gave it to a few groups of mice and measured the level of Covid-19 antibodies that these mice produced over time.
The Sham group refers to those mice that were not given any virus and used as a control group.
A significant difference was observed, which is what the scientists wanted to see, and so they continued pumping the inactivated Covid-19 virus into animals that more closely resembled humans – primates like the macaque.
Random aside: a species of Malaysian macaques have been observed devouring rats! Here is the article. Be warned: graphic imagery within.
They actually ate so many that they saved the palm plantations from have to exterminate the rats.
These pig-tailed macaques had previously been considered a pest themselves as they do also eat palm oil fruits, but now they’re all good because they saved the companies pest control money.
Anyway, aside over.
And so the scientists pumped the virus into a few groups of Rhesus macaques, and monitored their Covid-19 antibody levels over time.
And to further confirm their tests, the scientists also took lung tissue samples from the macaques after injecting them with the actual Covid-19 virus. This is called the “challenge”.
So the results look promising! The vaccine caused a significant spike in Covid-19 antibodies in the macaques, and after challenge with the actual virus the group that had received the vaccine fared much better and did not exhibit full pneumonia that the control groups experienced.
As a final measure, the group performed multiple vaccinations on some more macaques just to see if the vaccine itself caused any issues. They pumped the vaccine three times at two week intervals.
Below are the results:
In order to show that the vaccine is safe, the scientists monitored a number of immune compounds in the macaques, namely cytokines. They also took samples of their lung tissue.
Cytokines are a class of little proteins in our bodies that our cells release in order to talk to each other, especially with regards to cell development and fighting off pathogens through inflammation and calling in defenses.
Basically, all you need to know is that when your body is responding to invading baddies like bacteria and viruses, your cells will release cytokines, so if cytokine levels go up, that means you’re preparing for battle!
This study found that cytokine levels didn’t go up with a few vaccine shots, and the lungs were all normal, suggesting that the vaccine is safe for use!
So the take-home message from all this is that there is a promising Covid-19 vaccine (at least for this specific strain that originated in China) and it works on our primate friends. This means they can start human trials now.
Human trials will take a block of time though, so don’t expect it anytime soon. But there is definitely hope for a vaccine.
I hope you found this Covid-19 vaccine study explanation useful and insightful. Feel free to post any questions you may have in the comment below!