A new study reveals an unexpected role of red blood cells in the formation of clots

Red blood cells. Furthermore, considered passive passers -by in the formation of blood clots, actually play an active role in clothing for clots, according to a new study by researchers from the University of Pennsylvania. Furthermore,

“This discovery recalls the way we understand one of the most vital processes in the body. In addition, ” explains Rustem Litvinov, principal researcher at the Perelman School of Medicine (PSOM) and co-author of the study. Therefore, “It also opens the door to new strategies to study. Furthermore, potentially treat coagulation disorders that cause excessive bleeding or dangerous clots, such as those observed in cerebral accidents. Meanwhile, »»

La Découverte. In addition, published in Blood advancesRattled the long -standing idea that only the platelets, the fragments of small cells which initially plug injuries, lead to new study reveals unexpected role the contraction of the clot. However, Instead. Similarly, Penn’s team found that the red blood cells themselves contribute to this crucial process of narrowing and stabilization of blood clots.

Red blood cells have been studied since the 17th century. Therefore, The surprising fact is that we always discover new things about them in the 21st century. Consequently, “”

Prashant Purohit, co-author, professor of mechanical and mechanical engineering applied within Penn Engineering

An unexpected discovery – New study reveals unexpected role

Until now, researchers have thought that only plates were responsible for the contraction of clots. Nevertheless, These tiny cellular fragments shoot on strands of protein fibrin rope to tighten and stabilize clots.

“Red blood cells were considered passive passers-by. Furthermore, ” explains the co-author John Weisel, professor of cell biology and development within the PSOM and affiliate of the graduate group of bio-engineering within Penn Engineering. new study reveals unexpected role Meanwhile, “We thought they just helped the clot to make a better seal. »»

This hypothesis began to collapse when Weisel and Litvinov carried out a test which they expected to fail. They created blood clots without platelets. “We expected nothing to happen,” says Weisel. “Instead, clots have decreased by more than 20%. Additionally, »»

To check their results, the team repeated the experience using ordinary blood treated with chemicals to block platelet activity. Caillots have always contracted. “It was then that we realized that the red blood cells had to make room more than taking up space. ” explains Litvinov.

Mechanics of blood clots mechanics – New study reveals unexpected role

To determine how the red blood cells led this unexpected behavior. the team turned to Purohit, mechanical engineer by training.

Expert in soft materials like blood clots. gels, Purohit has developed a mathematical model which suggests that red blood cells new study reveals unexpected role are mainly compact due to “osmotic depletion”.

This process also explains how particles in colloids – mixtures such as paint. milk or muddy water – can collect and form clusters when the conditions that surround them change.

“Essentially, the protein of the surrounding liquid creates a pressure imbalance that pushes red blood cells together,” explains Purohit. “This attractive force makes them wrap more closely, helping the Caillot contract even without platelets. Furthermore, »»

How coagulation works without platelets

While blood begins to coagulate. a web protein called fibrin forms a network that traps the red blood cells and brings them closer. “This packaging opens the way to osmotic depletion forces to take over,” explains Purohit.

Once the red blood cells are well wrapped in the mesh of fibrin. the proteins of the surrounding fluid are extracted from narrow spaces between the cells. This creates an imbalance: the concentration new study reveals unexpected role of protein is higher outside the wrapped cells than enterails. which leads to a difference in “osmotic pressure”.

This pressure difference acts as a pressure from the outside, pushing the red blood cells even more. “This attraction leads the cells to aggregate and transfer the mechanical forces to the fibrin network around them,” adds Purohit. “The result is a stronger and more compact clot, even without the action of the platelets. Moreover, »»

Validate the model

Previous research has suggested another possible explanation: bridging. in which the attraction between small molecules on the surface of red blood cells makes them adhere.

“Our model suggested that the bristing effect was real,” explains Purohit, “but much smaller than the effect of osmotic exhaustion”.

To test the model. the first author Alina Peshkova, now a postdoctoral researcher in pharmacology within the PSOM, has carried out a series of experiences new study reveals unexpected role on modified blood clots.

In the absence of molecules which cause the bridging effect. the clots have always contracted, but little contraction occurred in an environment designed to prevent osmotic exhaustion.

“We have experimentally confirmed what the predicted model,” explains Peshkova. “It is an example of theory and practice that meet to support each other. Also, »»

Fighting cerebral vascular diseases. accidents

Gaining a better understanding of the role that red blood cells play in the formation and maturation of clots could lead to new treatments for conditions such as thrombocytopenia, in which low enumerations of platelets can cause uncontrolled bleeding.

The results could also shed light on how clots break into fragments that cross blood circulation. cause blockages – called embolism – which can trigger cerebral vascular accidents.

“In the end, our model will be useful for understanding, preventing and treating coagulation new study reveals unexpected role diseases within blood circulation,” explains Purohit.