'Levitating' proteins could help diagnose opioid abuse, other diseases

February 04, 2020

EAST LANSING, Mich. - Researchers at Michigan State University's Precision Health Program have helped develop a fascinating new method for detecting the density of proteins in the blood - a method that could vastly improve the rate at which diseases are detected and diagnosed.

The method, called "magnetic levitation," or MagLev, had previously been used to separate different types of particles in solutions, arranging them in groups based on their relative densities rather than weight. Now, two new studies by Precision Health's Morteza Mahmoudi, assistant professor, and Ali Akbar Ashkarran, research associate, illustrate how the method also can be applied to human blood plasma - the liquid component of blood. Plasma contains many types of proteins that perform a multitude of functions in the body.

"When we put something in liquid, it separates into sediment by weight," Mahmoudi said. "But another force - the magnetic force ¬- can cancel out weight and levitate the proteins. This permits us to much more precisely define the density of proteins in solution."

Being able to accurately measure the density of proteins in the body is important since proteins play important roles in both health and disease states. For example, lipoproteins transport fats to cells, antibody proteins play roles in immunity and coagulation proteins help blood clot. Current methods to measure density of proteins in liquid are unreliable and often destroy the fundamental properties of the proteins.

In the first study, published in Analytical Chemistry, the team applied the MagLev technique in a small tube containing magnetic nanoparticles into which plasma proteins had been introduced. Over a three-hour period, the team observed the emergence of a number of distinct bands representing various forms of proteins.

"The proteins created specific shapes when they were levitated," Mahmoudi said. "It looks like a 'smiley face' of layers."

Measuring the density of the bands, the team arrived at two noteworthy findings. The first was that there was no correlation between the density of a protein and its molecular weight, which came as a surprise since it goes against conventional thinking. The other was that the average density of proteins was much lower than previous studies had suggested.

The mechanism by which the proteins separate into layers by density isn't totally clear, but it may be due to structural differences and/or protein-to-protein interactions.

"The findings are of crucial importance, as protein density is being used to define proteins' physical properties, including their 3D structures," Mahmoudi said. "In addition, the accurate density of proteins enables us to design safer and more efficient therapeutic agents, such as nanomedicine."

So, the MagLev method isn't just a fun research tool - it has exciting clinical implications. The particular "signature" of an individual's plasma proteins might tell a doctor much about a patient's health status.

Indeed, this is what Mahmoudi and Ashkarran laid out in the second study, published in Advanced Healthcare Materials. They tested the MagLev method clinically by comparing the plasma of healthy people to that of people who abuse opioids. From image analysis, they found distinct and reliable differences in the spectrum of plasma proteins of healthy individuals and those who abuse opioids.

For instance, donors abusing opioids had higher levels of certain variants of hemoglobin, a finding that corresponds to previous literature indicating higher levels of hemoglobin in the blood and in the brains of people.

The method holds particular promise for diagnostics, a potentially lengthy process that can delay treatment. Mahmoudi said he and his team are currently working on using MagLev to identify other types of chronic disease, like multiple sclerosis and cancer, where accurate diagnosis is critical and in many cases lifesaving.

"There are four subtypes of MS, but diagnosis is currently based on the patient's behavior, symptoms, and his or her response to treatment," Mahmoudi said. "There is no biomarker or MRI test to diagnose the different subtypes at the early stages. Correctly diagnosing the type of MS is critical, since it dictates which type of treatment is appropriate. We hope this MagLev method will give clinicians a technique to define the subtypes."

The team is also looking at whether MagLev can be used in diagnosing cancer, where early detection can affect survival rates.

"If we can use the technique to detect cancer sooner, many more cancers could be treated successfully," Mahmoudi said. "Studies show that many types of cancers can be cured if they get detected at the early stages. The real problem is late detection."
-end-
Kenneth Suslick of the University of Illinois is an additional author of the study published in Analytical Chemistry.

Tina Olfatbakhsh, Milad Ramezankhani, Abbas Milani and Sepideh Pakpour, all with University of British Columbia; and Richard Crist and Wade Berrettini of University of Pennsylvania, are additional authors on the paper published in Advanced Healthcare Materials.

(Note for media: Please include a link to the original papers in online coverage: https://pubs.acs.org/doi/full/10.1021/acs.analchem.9b05101https://onlinelibrary.wiley.com/doi/full/10.1002/adhm.201901608

Michigan State University has been working to advance the common good in uncommon ways for 160 years. One of the top research universities in the world, MSU focuses its vast resources on creating solutions to some of the world's most pressing challenges, while providing life-changing opportunities to a diverse and inclusive academic community through more than 200 programs of study in 17 degree-granting colleges.

For MSU news on the Web, go to MSUToday. Follow MSU News on Twitter at twitter.com/MSUnews.

Michigan State University

Related Cancer Articles from Brightsurf:

New blood cancer treatment works by selectively interfering with cancer cell signalling
University of Alberta scientists have identified the mechanism of action behind a new type of precision cancer drug for blood cancers that is set for human trials, according to research published in Nature Communications.

UCI researchers uncover cancer cell vulnerabilities; may lead to better cancer therapies
A new University of California, Irvine-led study reveals a protein responsible for genetic changes resulting in a variety of cancers, may also be the key to more effective, targeted cancer therapy.

Breast cancer treatment costs highest among young women with metastic cancer
In a fight for their lives, young women, age 18-44, spend double the amount of older women to survive metastatic breast cancer, according to a large statewide study by the University of North Carolina at Chapel Hill.

Cancer mortality continues steady decline, driven by progress against lung cancer
The cancer death rate declined by 29% from 1991 to 2017, including a 2.2% drop from 2016 to 2017, the largest single-year drop in cancer mortality ever reported.

Stress in cervical cancer patients associated with higher risk of cancer-specific mortality
Psychological stress was associated with a higher risk of cancer-specific mortality in women diagnosed with cervical cancer.

Cancer-sniffing dogs 97% accurate in identifying lung cancer, according to study in JAOA
The next step will be to further fractionate the samples based on chemical and physical properties, presenting them back to the dogs until the specific biomarkers for each cancer are identified.

Moffitt Cancer Center researchers identify one way T cell function may fail in cancer
Moffitt Cancer Center researchers have discovered a mechanism by which one type of immune cell, CD8+ T cells, can become dysfunctional, impeding its ability to seek and kill cancer cells.

More cancer survivors, fewer cancer specialists point to challenge in meeting care needs
An aging population, a growing number of cancer survivors, and a projected shortage of cancer care providers will result in a challenge in delivering the care for cancer survivors in the United States if systemic changes are not made.

New cancer vaccine platform a potential tool for efficacious targeted cancer therapy
Researchers at the University of Helsinki have discovered a solution in the form of a cancer vaccine platform for improving the efficacy of oncolytic viruses used in cancer treatment.

American Cancer Society outlines blueprint for cancer control in the 21st century
The American Cancer Society is outlining its vision for cancer control in the decades ahead in a series of articles that forms the basis of a national cancer control plan.

Read More: Cancer News and Cancer Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.