Coronavirus Is Similar To HIV In Infection Pathway
According to the new research by scientists in China and Europe, the new coronavirus has an HIV-like mutation that increases its ability to bind to human cells 1000 fold compared to the SARS virus.
This new discovery can help scientists to explain the source of the virus as well as ways to fight them.
SARS binds to a receptor protein called ACE2 on the cell membrane to invade the cell. Since the new coronavirus shares 80% of its genome with SARS, scientists expected it to follow the same path as SARS. The ACE2 protein is not present in most of healthy people which limited the outbreak of SARS to 8,000 people in 2002-2003.
On the other hand, Ebola and HIV viruses target an enzyme called furin, which is a protein activator in the human body. They are known for activating the dormant or inactive proteins by cutting them at specific points.
When Professor Ruan Jishou and his team at Nankai University in Tianjin studied the genome sequence of the novel coronavirus, they found some mutated genes similar to those found in Ebola and HIV, but not present in SARS.
These new findings might be suggesting that the new coronavirus is significantly different from SARS regarding the infection pathway. According to the new study the mutations can create a structure called cleavage site in the spike protein of new coronavirus.
The virus uses its spike protein to hook on to the human cell, but this spike protein is normally inactive. The cleavage structure formed due to the mutation can trick the furin protein on the human cell membrane to cleave and activate the spike protein, enabling the fusion of cellular and viral membranes. This binding method is 1,000 times stronger than that of SARS.
Professor Li Hua from Huazhong University of Science and Technology in Wuhan and his team confirmed Ruan’s findings in a follow-up study.
The mutations could not be found in MERS, SARS or Bat-CoVRaTG13, a bat coronavirus from which the novel coronavirus was thought to be originated because of its 96% similarity in genes.
This could be the reason why the new Covid-19 is more contagious than any other coronaviruses.
French scientist Etienne Decroly at Aix-Marseille University also found the ‘furin-like cleavage site’ in the novel coronavirus confirming that the new coronavirus is similar to HIV in infection pathway.
Over the past few months, the understanding of the new coronavirus has dramatically changed. There was no evidence of human-to-human transmission initially due to which the virus was not considered as a major threat. But the assumption was invalidated soon and the virus infected more than 89,000 around the world.
The new findings have given Chinese researchers hope that a drug targeting furin enzyme could prevent virus replication in the body. HIV therapeutic drugs like Tenofovir Disoproxil, Tenofovir Alafenamide, Indinavir, and Dolutegravir and hepatitis C therapeutic drugs including Boceprevir and Telaprevir are some of the drugs that target furin enzyme.
This is in line with the self-administration of HIV drugs by some Chinese doctors to cure coronavirus, but there is no clinical evidence yet to support the theory.
The unexpected mutation could have come from many possible sources like the coronavirus in rats or species of avian flu.