University of Ottawa-led team found a new viral entry for SARS-CoV-2 and suggests it may be able to use proteins to infect a wider range of cells.
One of the many pressing research undertakings by the scientific community amid the ongoing COVID-19 pandemic has focused on ways the coronavirus manages to enter host cells.
Now, in a study adding to the pool of knowledge about viral entry, Dr. Marceline Côté's Faculty of Medicine lab and collaborators have published a highly compelling study showing a previously unrecognized entryway for SARS-CoV-2, the virus that causes COVID-19 and the driver of the global health crisis that's transformed the world.
Dr. Marceline Côté's team from the University of Ottawa has found a new viral entry for SARS-CoV-2 and suggests it may be able to use proteins to infect a wider range of cells. Credit: University of Ottawa
Previous studies have shown that SARS-CoV-2 as well as an earlier coronavirus, SARS-CoV-1, the virus behind the SARS outbreak in 2003, enter cells via two distinct pathways. The new research led by Dr. Côté's lab shows a third entry route.
This viral entryway involves metalloproteinases, enzymes in the body with a catalytic mechanism that requires a metal, such as zinc atoms, to function.
Over a series of experiments starting in 2020, Dr. Côté's research team discovered that SARS-COV-2 can enter cells in a metalloproteinase-dependent manner. The team describes a role for two matrix metalloproteinases—MMP-2 and MMP-9—in the activation of the spike glycoprotein.
What are the ramifications of this kind of viral entry? The study published in a recent issue of iScience, an open access journal from Cell Press, suggests that variants that gravitate toward metalloproteinases may cause more havoc.
The team's experiments showed that some variants clearly prefer the metalloproteinases for activation. For instance, the Delta variant, a more pathogenic variant that surged in 2021, commonly used metalloproteinases for entry. Its less pathogenic successor, Omicron, did not.
"SARS-CoV-2 may be able to use proteins, which are typically secreted by some activated immune cells, to cause more damage and potentially infect a wider range of cells and tissues," says Dr. Côté, a Faculty associate professor who is the holder of the Canada Research Chair in Molecular Virology and Antiviral Therapeutics.
The entry mechanism could also play a role in disease progression.
Dr. Côté says the findings could have implications in the progression to severe illness and some post-COVID-19 conditions, such as the complex array of post-infection symptoms known as "long Covid."
News
We May Never Know if AI Is Conscious, Says Cambridge Philosopher
As claims about conscious AI grow louder, a Cambridge philosopher argues that we lack the evidence to know whether machines can truly be conscious, let alone morally significant. A philosopher at the University of [...]
AI Helped Scientists Stop a Virus With One Tiny Change
Using AI, researchers identified one tiny molecular interaction that viruses need to infect cells. Disrupting it stopped the virus before infection could begin. Washington State University scientists have uncovered a method to interfere with a key [...]
Deadly Hospital Fungus May Finally Have a Weakness
A deadly, drug-resistant hospital fungus may finally have a weakness—and scientists think they’ve found it. Researchers have identified a genetic process that could open the door to new treatments for a dangerous fungal infection [...]
Fever-Proof Bird Flu Variant Could Fuel the Next Pandemic
Bird flu viruses present a significant risk to humans because they can continue replicating at temperatures higher than a typical fever. Fever is one of the body’s main tools for slowing or stopping viral [...]
What could the future of nanoscience look like?
Society has a lot to thank for nanoscience. From improved health monitoring to reducing the size of electronics, scientists’ ability to delve deeper and better understand chemistry at the nanoscale has opened up numerous [...]
Scientists Melt Cancer’s Hidden “Power Hubs” and Stop Tumor Growth
Researchers discovered that in a rare kidney cancer, RNA builds droplet-like hubs that act as growth control centers inside tumor cells. By engineering a molecular switch to dissolve these hubs, they were able to halt cancer [...]
Platelet-inspired nanoparticles could improve treatment of inflammatory diseases
Scientists have developed platelet-inspired nanoparticles that deliver anti-inflammatory drugs directly to brain-computer interface implants, doubling their effectiveness. Scientists have found a way to improve the performance of brain-computer interface (BCI) electrodes by delivering anti-inflammatory drugs directly [...]
After 150 years, a new chapter in cancer therapy is finally beginning
For decades, researchers have been looking for ways to destroy cancer cells in a targeted manner without further weakening the body. But for many patients whose immune system is severely impaired by chemotherapy or radiation, [...]
Older chemical libraries show promise for fighting resistant strains of COVID-19 virus
SARS‑CoV‑2, the virus that causes COVID-19, continues to mutate, with some newer strains becoming less responsive to current antiviral treatments like Paxlovid. Now, University of California San Diego scientists and an international team of [...]
Lower doses of immunotherapy for skin cancer give better results, study suggests
According to a new study, lower doses of approved immunotherapy for malignant melanoma can give better results against tumors, while reducing side effects. This is reported by researchers at Karolinska Institutet in the Journal of the National [...]
Researchers highlight five pathways through which microplastics can harm the brain
Microplastics could be fueling neurodegenerative diseases like Alzheimer's and Parkinson's, with a new study highlighting five ways microplastics can trigger inflammation and damage in the brain. More than 57 million people live with dementia, [...]
Tiny Metal Nanodots Obliterate Cancer Cells While Largely Sparing Healthy Tissue
Scientists have developed tiny metal-oxide particles that push cancer cells past their stress limits while sparing healthy tissue. An international team led by RMIT University has developed tiny particles called nanodots, crafted from a metallic compound, [...]
Gold Nanoclusters Could Supercharge Quantum Computers
Researchers found that gold “super atoms” can behave like the atoms in top-tier quantum systems—only far easier to scale. These tiny clusters can be customized at the molecular level, offering a powerful, tunable foundation [...]
A single shot of HPV vaccine may be enough to fight cervical cancer, study finds
WASHINGTON -- A single HPV vaccination appears just as effective as two doses at preventing the viral infection that causes cervical cancer, researchers reported Wednesday. HPV, or human papillomavirus, is very common and spread [...]
New technique overcomes technological barrier in 3D brain imaging
Scientists at the Swiss Light Source SLS have succeeded in mapping a piece of brain tissue in 3D at unprecedented resolution using X-rays, non-destructively. The breakthrough overcomes a long-standing technological barrier that had limited [...]
Scientists Uncover Hidden Blood Pattern in Long COVID
Researchers found persistent microclot and NET structures in Long COVID blood that may explain long-lasting symptoms. Researchers examining Long COVID have identified a structural connection between circulating microclots and neutrophil extracellular traps (NETs). The [...]
