Illustrative
Illustrative iStock

New research presented at a meeting of the American Heart Association this week and not yet peer
reviewed has linked the spike protein of the coronavirus, SARS-CoV-2, to heart muscle injury via the
inflammatory process.

The spike protein is a protein that is found on the surface of the COVID-19-causing coronavirus, and
has long been believed to be responsible for many of the serious consequences of COVID infection. It
can infect not only the lungs but also other organs, leading to severe damage and also death.

“It’s already known from the clinical side that COVID-19 infection can induce heart injury, however, what we don’t know is the mechanistic details of how this occurs. What we suspect is that the spike protein has unknown pathological roles,” said Zhiqiang Lin, Ph.D., lead author of the study and an assistant professor at the Masonic Medical Research Institute in Utica, New York. “Our data show that the spike protein from SARS-CoV-2 causes heart muscle damage.”

Lin and her team compared the body's immune response following COVID infection to that following another coronavirus infection caused by a virus with a different type of spike protein. They found that the SARS-CoV-2 spike protein activated the natural immune response in heart muscle cells and damaged the heart, but the NL63 spike protein did not.

“The fact that the SARS-CoV-2 spike protein is activating the natural immune response may explain the high virulence compared to the other coronaviruses,” Lin said.

“We found direct evidence that the SARS-CoV-2 spike protein is toxic to heart muscle cells.” Damage observed included heart dysfunction, enlargement, and cardiac inflammation, observed both in humans and in lab mice.

The mechanism via which the damage occurs remains unknown, and this will be a focus of future research. At the present, two main possibilities are under consideration. The first is that spike protein is expressed in the virus-infected heart muscle cells and thereby directly activates inflammation; the second is that the virus spike protein is shed into the bloodstream, and the circulating spike proteins damage the heart.

According to Lin, the findings show “why it’s important to get vaccinated and prevent this disease.”

However, Dr Anthony Fauci recently admitted that the vaccines are no longer very effective against infection, noting that, "Although the vaccines, even with boosters, continue to protect quite well against severe disease ... because of the exquisitely high transmissibility of these emerging variants, people are getting infected at a very high rate ... Immunity isn’t measured in decades or lifetimes. It’s measured in several months."

Meanwhile, the biotech company TScan Therapeutics is in the process of developing a new type of COVID vaccine that is focused on the T-cell immune response to infection rather than the creation of neutralizing antibodies to the spike protein.