Immune System Culprit in Severe COVID Cases

A particular immune response pathway that leads to severe illness and death in people infected by the SARS-CoV-2 virus has been discovered.

A particular immune response pathway that leads to severe illness and death in people infected by the SARS-CoV-2 virus has been discovered by Yale researchers.

The study was published in the journal Nature.

Fluvoxamine: An OCD Drug can Prevent Covid-19 Patients from Hospitalization
Fluvoxamine has been proven among one such drug that could be used to treat COVID-19. Dozens of COVID patients showed no clinical deterioration in their symptoms when treated with a drug, fluvoxamine.

‘Researchers have known that once the COVID-19 virus infects the lungs it can trigger what has been called a “cytokine storm,” or an overactive immune response that leads to deadly inflammation in the lungs.’

For the new study, a Yale team led by postdoctoral fellow Esen Sefik, who is part of the lab of senior author Richard Flavell, studied the effects of SARS-CoV-2 infection in mice engineered to have a human immune system.

To their surprise, they found that immune cells themselves, not just epithelial cells lining the lung, can harbor the virus. When the body detects the virus in these cells, inflammasomes, part of the immune system’s early warning system, produce and release cytokines which prompt these immune cells to commit suicide in an attempt to abort infection. However, the cytokines also recruit even more inflammatory cells to the lungs from the blood, which drives a vicious cycle that leads to pneumonia.

“It’s like a broadcast system, but in this case the message is lethal,” said Flavell.

Inflammasome Pathway and COVID-19

In the mouse model of COVID-19, researchers were able to rescue infected mice from pneumonia by blocking the NLPR3 inflammasome pathway. With the inflammasome pathway blocked, immune system cells were still infected. But they were no longer inflammatory and therefore could not contribute to damaging levels of inflammation, researchers found.

Green Fungus or Aspergillosis and COVID-19 Infection
Green fungus or Aspergillosis is caused by a common mold, which exists both indoors and outdoors. Every day, people inhale Aspergillus spores, but it isn't harmful. However, it affects people who have a weak immune system. If the infection is left untreated, it can cause pneumonia.

One byproduct of this rescue, however, is that the cells no longer die and as a consequence release more virus. Nonetheless, blockade of the inflammasome pathway along with antiviral treatment could provide a way to treat COVID-19 pneumonia and prevent severe cases of COVID -19, researchers say.

Flavell said that although there are no approved drugs that block the NLPR3 pathway, several pharmaceutical and biotech companies are developing them.

Test your Knowledge on Coronavirus (COVID-19)
Coronavirus is a large positive-strand RNA virus that is surrounded by a protein envelope. The virus obtains its name from the S protein spikes on its surface, which resemble a crown. The overall pattern of increasing coronavirus cases is shown to spike up with the “second wave” of COVID-19.

With spiking effects of the second wave of coronavirus, the best way to keep it at bay is to follow COVID-appropriate safety practices like wearing a mask, regularly cleaning your hands, and coughing into a bent elbow or tissue along with physical distancing (6 feet about 2 arm's length), that may help evade the severity of COVID-19 infection.

The research was funded by the Howard Hughes Medical Institute.

Source-Eurekalert

COVID-19 Vaccine Method Helps Repair Damaged Heart Muscle
A strategy for delivering genetic material to the body is tested as a way to repair damaged heart muscle after a heart attack.