Warning: this paper has generated an answer which claims that the authors used wrong methodology to get to their results – so this could be all wrong. Remember, we are in a research phase here.
This paper totally changes the way we understand how Covid-19 works. By using only computer models, the authors made fascinating discoveries. Here is a very short summary of their findings.
Covid-19 attacks hemoglobin
The authors discovered that the virus doesn’t attack the lungs, but rather… hemoglobin. You know, that red thing found in red blood cells which carries oxygen in the body.
As the virus attacks hemoglobin (actually only the “heme” part), it impairs the transport of oxygen. Therefore, it deprives the body from this essential component. Besides, it also reduces the transport of carbon dioxide, which slowly poisons the body.
As for the lungs, they do still try to transmit oxygen. Unfortunately, that oxygen remains stuck in the alveoli due to lack of hemoglobin in the blood. This creates an inflammation of the alveoli and a general irritation of the lungs.
Thus, it is not surprising that ventilators have little effect on patients, as many doctors report. We would definitely need something to cleanse the blood and enable transport of oxygen and carbon dioxide.
Covid-19 uses porphyrins to enter cells
We thought that Covid-19 entered the cells through ACE2 receptors. However, we know since the beginning that its affinity with those receptors is quite limited. Something was off, but we stuck to it for want of anything better.
This paper shows that the virus can dock on porphyrins (and synthesize some as well). These are building blocks of all living things. They were some of the first organic compounds that made life possible. Here comes the catch: some porphyrins can enter the cells, to bring in oxygen or some metals, for instance.
The virus, thanks to its docking mechanisms to those molecules, could use them as keys to enter the cells. Therefore, it wouldn’t even need to use ACE2 receptors.
Analysis on some potential drugs/cures
This paper shows that chloroquine can dock on some parts of the virus which attack hemoglobin. Of course, this is great news. However, the authors’ models suggest that the binding is not very strong. This could explain why it seems that chloroquine is not a miraculous treatment. Instead, its efficiency varies greatly from one patient to the next.
An antiviral, Favipiravir, can dock on portions of the virus which normally lock on porphyrins. Therefore, it prevents the virus from using porphyrins as keys to enter the cells. Thus, this antiviral can slow down the proliferation of the virus. This is especially true at the beginning of the infection.
The authors carefully note that further research is needed to confirm their findings. Indeed, those are only theoretical models that need to be tested in real life. However, their research offers tremendous perspectives in enhancing our understanding of this virus. Outstanding!