A new study has found that covid-19 stimulates the production of blood-borne antibodies, causing clots in hospitalized people with the disease. Credit: Stephanie King / Michigan Medicine
Blood clots continue to wreak havoc for critically ill patients COVID-19 Infections, and a new study explains what can spark them in half the patients.
The culprit: an autoimmune antibody that spreads in the blood, attacks cells and clots in arteries, veins and microscopic vessels. Blood clots can lead to fatal events such as stroke. And, in Covid-19, microscopic clots can restrict blood flow to the lungs, impairing oxygen exchange.
Outside of novel coronavirus infections, these clotting antibodies are found especially in patients with autoimmune disease antiphospholipid syndrome. The connection between autoantibodies and COVID-19 was unexpected, says Yogen Kanthi, MD, assistant professor at the Frankel Cardiovascular Center of Michigan Medicine and co-author of the National Heart, Lung and Blood Institute of Health Laskar Investigators.
“In patients with Covid-1, we see an endless, self-expanding cycle of inflammation and clotting in the body,” says Kanti. “Now we’re learning that an ontibodies can be the culprit in this loop of clotting and inflammation, which makes people already struggling in a state of disarray.”
‘Some of the worst lumps we’ve ever seen
Co-author Jason Knight, MD, PhD in Michigan Medicine Arthritis, has been studying antiphospholipid syndrome antibodies in the general population for years.
“Half of the patients admitted to the hospital in Covid-1 were positive for at least one of the three antibodies, which is quite surprising,” said Knight, an associate professor of internal medicine and a leading specialist in diseases caused by ankylosing spondylitis.
In the new Science Translation The medicine of translation In the release, they found that about half of all patients with very sick patients with COVID-19 showed a combination of high levels of dangerous antibodies and super-active neutrophils, which are destructive, exploding white blood cells. In April, the team first reported an increase in neutrophil extracellular traps in hospitalized patients with severe COVID-19.
To learn more, they studied explosive neutrophils and COVID-19 antibodies in mouse models to see if there could be a dangerous combination behind these clots.
“Antibodies from patients with active Covid-1 infection have caused an astonishing amount of clotting in animals, the worst clotting we have ever seen,” says Kanti. “We have discovered a new mechanism by which COVID-19 patients can have blood clots.”
COVID-19 blood clot attack from all corners
The researchers say these findings are not yet ready for clinical practice, but they do give a new perspective to strong thrombosis and inflammatory research in COVID-19 patients.
Kanthi, Knight, first author U (Ray) Xuo, MD, and colleagues now want to know if antibodies that are blocked or removed will have better results for critically ill patients with high levels of these antibodies.
If so, it guarantees invasive treatment, such as plasmapheresis, commonly used in severe autoimmune diseases, Xu explains. This includes bleeding by IV, filtering and refreshing Plasma It does not have the antibodies associated with blood clots.
“We know that people with higher levels of antibodies were doing worse in terms of respiratory function, and antibodies also cause inflammation in healthy cells,” said Xuo, an internal assistant professor of Michigan medicine and a rheumatologist.
“We don’t yet know what is triggering the body to produce these antibodies, so the next step will be additional research to identify the targets and targets of the antibodies,” Knight adds. “
In addition, these findings raise new questions surrounding the potential use of plasma as a potential COVID-19 treatment, but the team says more research is needed to investigate this concern.
Knight says, “We are now investigating how long these antibodies remain in circulation after recovery from the novel coronavirus.
Researchers are also conducting a randomized clinical trial called DICER, which is testing the well-known anti-clotting agent, dipyridamole, in patients with Covid-19 to determine if it is more effective than placebo in reducing excessive blood clotting.
Kanti says, “Dipyridamole is an older drug that is safer, cheaper and scalable. “The FDA approved it 20 years ago to prevent clots, but we’ve only recently found the possibility of blocking this particular type of inflammation that occurs in covid.”
Reference: Yu Xuo, Shana K. Estes, Ramzan A. Ali, Alex A. Gandhi, Srilakshmi Yalavarthi, Hu Shi, Gautam Sule, Kelsey Gokman, Jacqueline A. By Madison, “Prothrombotic tick an tontibodies in patients’ serum in COVID-19”. , Melanie Xuo, Vinita Yadav, Jintao Wang, Warren Woodard, Sean P. Lazak, Nazira L. Lugogo, Stephanie A. Smith, James H. Morrissey, Yogendra Kanthi and Jason S. Knight, 2 November 2020, Science Translation The medicine of translation.
DOI: 10.1126 / skittranslated.ABD3876
