Daniel Irimia, MD, PhD, Associate Professor and Deputy Director of the BioMEMS Resource Center at the Center for Engineering in Medicine & Surgery (CEMS). Internationally recognized expert in bioengineered microsystems for cellular chemotaxis and other functional assays
Michael VanElzakker PhD, Instructor, Division of Neurotherapeutics, Harvard Medical School
Brittany Boribong PhD, Postdoctoral research fellow, Harvard Medical School
Amy Proal, PhD, President/Microbiologist, PolyBio Research Foundation
Dr. Resia Pretorius, PhD, Distinguished Professor and Department Head of Physiological Sciences. Stellenbosch University
A project is using advanced microscopy and microfluidic assays to identify & quantify 1) fibrinaloid microclots 2) activated platelets 3) neutrophil motility and neutrophil extracellular trap (NET) formation in blood collected from patients with LongCOVID, ME/CFS, and post-treatment Lyme disease syndrome versus healthy controls. Because inflammation associated with microclot and NET formation may damage the blood vessels, a detailed multiplex panel of cardiovascular health markers is also being measured in all study participants.
Project collaborator Dr. Resia Pretorius and team recently identified fibrinaloid microclots in blood collected from individuals with LongCOVID. To expand on the findings, PolyBio Research Foundation worked directly with Dr. Pretorius to identify similar, smaller fibrinaloid microclots in blood collected from patients with ME/CFS. The current project expands on these findings by identifying and quantifying microclots in a new group of LongCOVID and ME/CFS study participants, with post-treatment Lyme disease syndrome patients added in as a third arm for comparison and investigation. Platelet activation will also be characterized and quantified in all study participants.
A second part of the study focuses on characterizing clotting-related immune activity in blood. Neutrophils are the most common immune cell in blood and respond rapidly to signals of injury or infection. When activated, they exhibit observable behavioral changes that can serve as biomarkers, and their abnormal behavior may directly contribute to symptoms in patients with infection-associated chronic disease. Neutrophil activity is also intricately connected to clotting processes. For example, blood-cell derived microparticles from neutrophils have been implicated in thrombus (blood clot) formation. The project team has developed an advanced panel of microfluidic assays that probe neutrophil function from a single drop of live blood, and preliminary studies suggest that multiple neutrophil functions might be altered in LongCOVID, ME/CFS, and post-treatment Lyme disease syndrome relative to progression of disease. These include changes in neutrophil motility (their ability to move and respond to stimuli).
Neutrophils in ME/CFS, LongCOVID and post-treatment Lyme disease syndrome patients may also have an increased tendency to produce extensions called Neutrophil Extracellular Traps (NETs). NETs trap pathogens, but are also implicated in clotting processes. The team is consequently additionally testing for NETs in study participants by using microfluidic capture directly from live blood samples. They are also measuring baseline and stimulated NET formation rates by time-lapse fluorescence imaging in microfluidic chambers. A significant advantage of this approach is its analysis of live (not frozen) blood cells.
A third component of the study will measure and compare a detailed panel of circulating markers that are associated with vascular damage and growth. This will allow a better understanding of any potential effects that microclots or NETs may have on systemic blood vessels.
The ME/CFS portion of this study is funded by an NIH R21.