Study Yields Important Findings on the Functions of von Willebrand Factor

Researchers at the Boston Children’s Program in Cellular and Molecular Medicine and the Harvard Medical School recently made important discoveries relevant to the functioning of von Willebrand factor (VWF). The study, “Flow-induced Elongation of von Willebrand Factor Precedes Tension-Dependent Activation,” was published online, August 23, 2017, in the journal Nature Communications.

Using fluorescent imaging and microfluidic tools, Jiang and his colleagues recreated the blood flow that occurs in humans, particularly the function of VWF within the bloodstream. Through a series of valves, cylinders and tubes, investigators were able to mimic the increase in blood flow that occurs after an injury.

Experiments showed that as the blood flow grew more intense, changes in the shape of VWF would occur. VWF molecules, which are normally rounded and compact, quickly became rapidly elongated in response to the increased tension. Scientists also observed that as VWF elongates it binds with platelets to ensure that a viable blood clot forms. Notably, VWF activates locally at the site of an injury and not in other parts of the body. 

“If you can imagine stretching out your arms, and then opening your hands to capture platelets, that’s basically what we are seeing VWF do in response to bleeding,” said researcher Wesley P. Wong, PhD. “It’s so important that this process occurs only when and where it is needed—this two-step activation process makes that possible.”

While these findings could have future implications for treatment, leading to more novel therapies, they are also scientifically noteworthy. Researchers are no doubt excited to uncover such valuable molecular-level insights on the intricacies of the bloodstream and the mechanisms of VWF.

“This experiment really represents a new platform for seeing and measuring what’s happening in the blood on a molecular level,” said Wong. “Through the use of novel microfluidic technologies that allow us to mimic the body’s vasculature in combination with single-molecule imaging techniques, we are finally able to capture striking images that uncover the mystery of nature’s forces at work in our bodies.”
       
Source: Genetic Engineering & Biotechnology News, August 23, 2017. 

Provided by the National Hemophilia Foundation.