New study shows role of blood cells in thrombosis of patients with Covid

A new study in the online edition of the scientific journal Nature shows that monocytes, blood cells in the body’s defense system, may play an important role in thrombus formation in patients with Covid-19.

Thrombi are blood clots formed in the veins or arteries that hinder blood circulation to other parts of the body, generating what we call thrombosis.

Covid is a disease known as thrombogenic, that is, it is characterized by having a high risk of clot formation. The incidence of thrombosis in these patients ranges from 0.6 to 2 per 100,000 people, about 8 to 10 times greater than the risk of thrombosis for some vaccines against the disease.

In the new study, researchers analyzed blood cells from patients with Covid and other healthy people without the disease, and compared the two groups by investigating various aspects, such as the presence of proteins on the surfaces of these cells.

Finally, they demonstrated that, in Covid-19, monocytes, responsible for the innate immune response (the person is already born with it), cause the production of some genes that lead to a “caste of prothrombotic effects”.

The work was celebrated in the scientific community for helping to understand how the cells that have the function of protecting us against infections can be affected by Sars-CoV-2 and, who knows, collaborate, in the future, in the development of possible future therapies.

During the pandemic, doctors adopted anticoagulants as routine treatment, such as heparin, to avoid or reduce such risks, often in doses above those recommended by health entities, such as the WHO (World Health Organization).

So far, though, studies that have evaluated the risks and benefits of these drugs to prevent post-Covid clot formation are inconclusive. That is, no benefits were observed in treatments indicated during the pandemic.

The study, however, has several limitations. According to infectologist Esper Kallás, a professor at USP who this Monday (2) will head the Butantan Institute, the work could have gone deeper in investigating, for example, whether these alterations in monocytes are also present in patients with different degrees of severity of Covid, and could also have compared children and adults, as children tend to have less serious conditions.

“Another issue is that the work does not prove that the findings in the laboratory will be reproduced in an animal model. It also does not show how these monocytes behave in other respiratory diseases, that is, if this action is only in Covid or in other diseases as well”, he says. him.