Coronavirus Outbreak: As health authorities everywhere are working to find a treatment for COVID-19, a team of chemists from Massachusetts Institute of Technology (MIT) have designed a drug candidate which they hope might be able to block the coronavirus from entering the human cell, MIT said in a statement. The potential treatment, the statement read, is a short protein fragment, also called peptide, which mimics the proteins found on human cells.
The researchers of MIT have found that peptide can bind to the viral protein which is used by the coronaviruses to enter the human cells, effectively rendering the coronaviruses useless. MIT associate professor of chemistry Brad Pentelute said that the team has found the lead compound which they want to explore, because it interacts with the viral protein in the way that they predicted and hence can possibly inhibit the entry of the virus into the human cells.
The team has reported its initial findings om bioRxiv, which is an online preprint server, and they have also sent samples of the peptide they have designed to collaborators who plan to conduct tests in human cells.
How did the researchers reach to this conclusion?
Pentelute's lab started working on this study in the beginning of March, soon after the information regarding the structure of the coronavirus and the human cell receptor it binds to was published by a group of researchers in China. Coronaviruses have protein spikes protruding from the viral envelope and studies have shown that the COVID-19-causing coronavirus has a specific region of its spike protein, called receptor binding domain, which binds to the ACE receptor, found on the surface of human cells, including those found in the lungs. ACE 2 was also the point which was used by coronaviruses to enter the human cells in the SARS outbreak of 2002-03.
Genwei Zhang, who is a postdoc in Pentelute's lab, hoped to develop drugs blocking the entry of coronavirus and hence, performed some computational simulations of the interactions between the receptor binding domain and the ACE2 receptor. Through these simulations, researchers were able to find out the point at which the receptor binding domain attaches to the receptor, which is a stretch of the ACE2 protein that forms a structure known as alpha helix.
Zhang said that the simulation helped the researchers understand how the atoms and biomolecules interacted with each other and the parts which were essential for this particular interaction. This helped them narrow down the regions which they needed to focus on for developing a treatment, Zhang added.
Moreover, although keeping mind the outbreak, MIT has been scaling down the on-campus research, Pentelute's lab had to obtain special permission to allow a small group of researchers to continue working on this project.
The team is now developing around a 100 different variants of peptide, hoping to increase its binding strength and its ability to remain stable in the body.
Pentelute said that his team is confident that they know the exact location where the molecule is interacting and he said they could use the information for further refinement, to get a higher affinity and potency to block the entry of coronaviruses into the human cells.