NASHVILLE, Tenn. — Potentially groundbreaking new research has discovered a new nanoparticle released by cells, dubbed a “supermere.” Even more intriguing, researchers from Vanderbilt University Medical Center say supermeres contain enzymes, proteins, and genetic material associated with some of the nastiest ailments known to humanity — including cancer, Alzheimer’s, cardiovascular disease, and even COVID-19.
Study authors report this discovery is a major step forward in modern science’s understanding of the role extracellular vesicles and nanoparticles play in transporting important chemical “messages” between cells, both in times of robust health and when we’re fighting a disease.
“We’ve identified a number of biomarkers and therapeutic targets in cancer and potentially in a number of other disease states that are cargo in these supermeres,” says senior study author, Robert Coffey, MD, in a university release. “What is left to do now is to figure out how these things get released.”
Dr. Coffey is world renown for his research on colorectal cancer. Today, his team is working on determining if finding and targeting cancer-specific nanoparticles in a person’s bloodstream may lead to earlier diagnoses and more effective treatment.
How did scientists find supermeres?
Rewind the clock to 2019, and Dennis Jeppesen, PhD, — a former research fellow in Coffey’s lab who is now a research instructor in medicine — was using advanced techniques to isolate and analyze small membrane-enclosed extracellular vesicles called “exosomes.” During that same year, Qin Zhang, PhD, a research assistant professor of medicine, put together an easy way to isolate a nanoparticle called an “exomere” that doesn’t have a surface coat.
In this latest research, Zhang opted to take the “supernatant” — the remaining fluid after spinning the exomeres into a “pellet” — and spin it faster and longer. That process led to the creation of a pellet of nanoparticles isolated from the supernatant of the exomere spin. Scientists call these pellets supermeres.
“They’re also super-interesting,” Dr. Coffey adds, “because they contain many cargo previously thought to be in exosomes.”
Supermeres carry a large portion of the extracellular RNA released by cells, which are usually present in the blood stream. Cancer-derived supermeres can even “transfer” drug resistance to tumor cells, possibly due to the RNA cargo they carry.
Moreover, supermeres carry TGFBI, a protein found in tumors that promotes tumor growth and progression. With this in mind, researchers theorize TGFBI may be a useful marker in liquid biopsies for patients with colorectal cancer.
A new decoy for COVID?
Supermere also carry ACE-2, a cell-surface receptor implicated heavily in cardiovascular disease and also known to be a target of the COVID-19 virus. Researchers speculate ACE2 carried by supermeres may one day be useful as a “decoy” for COVID virus cells to bind to, preventing true infection.
Finally, supermeres even carry APP, the amyloid-beta precursor protein heavily implicated in the onset of Alzheimer’s disease. The study finds supermeres can cross the blood-brain barrier, leaving the door open for their use as both a dementia detection and treatment method.
“The identification of this rich plethora of bioactive molecules … raises interesting questions about the function of supermeres, and heightens interest in the potential of these particles as biomarkers for diseases,” concludes researchers from the University of Notre Dame, in a review published with the study.
The study is published in the journal Nature Cell Biology.