Potential therapy derived from a banana protein works against SARS-CoV-2

The antiviral is also effective against all known coronaviruses and influenza.

12:28 PM

Author | Kelly Malcom

banana fingers going in pill bottle animated blue orange
Justine Ross, Michigan Medicine

On January 13, 2020, a paper touting the creation of a possible therapy that could be used to fight all known strains of the flu was published online.

One week later, the first laboratory confirmed case of SARS-CoV-2 set off the two and a half year-long COVID-19 pandemic in the United States.

Interestingly, prior to the arrival of the virus that temporarily shut down their work, the international study team behind the influenza paper had also investigated these banana-derived therapies for coronaviruses.

"At the time we thought MERS would be the big target, which we were worried about because of its 35% mortality rate," said David Markovitz, M.D., professor of internal medicine, Division of Infectious Diseases at the University of Michigan Medical School. (MERS, or Middle Eastern Respiratory Syndrome, caused a brief outbreak in 2015 and resulted in 858 confirmed deaths.)

A paper in Cell Reports Medicine details the efficacy of H84T-BanLec against all known human-infecting coronaviruses, including MERS, the original SARS, and SARS-CoV-2, including the Omicron variant. Markovitz is joined by two senior authors, Peter Hinterdorfer, Ph.D., of the Johannes Kepler University Institute of Biophysics and Kwok-Yung Yuen, MBBS, M.D., of the University of Hong Kong. The first author on the paper is Jasper Fuk-Woo Chan, M.D., of the University of Hong Kong.

"When COVID-19 occurred, we of course wanted to study the therapy's potential and discovered it was effective against every type of coronavirus, in vitro and in vivo," Markovitz said. "Whether delivered systemically or through the nose in animal models, or prophylactically or therapeutically early on in the illness, it worked."

H84T-BanLec is derived from a lectin (a carbohydrate-binding protein) isolated from banana fruit. It accomplishes its remarkable viral-blocking abilities by binding to high-mannose glycans, polysaccharides that are present on the surface of the viruses, but only very rarely on normal healthy human cells. After binding, the virus cannot enter cells to infect them.

Using atomic force microscopy and related methods, the team confirmed that H84T develops multiple strong bonds with the spike protein, which, said Markovitz, probably explains why it's hard for a coronavirus to be resistant to the lectin.

Despite their anti-viral potential, lectins have traditionally been avoided as possible therapies because they are proteins that can stimulate the immune system in a potentially harmful way, explains Markovitz. However, H84T-BanLec has been modified to remove this effect and showed no detrimental effects in the animal models.

While several treatments for COVID-19 currently exist, including remdesivir, Paxlovid and monoclonal antibodies, they have varied levels of effectiveness, side effects and ease of use and many have proven less effective as SARS-CoV-2 continues to evolve.

H84T-BanLec holds unique promise, according to the team, because it is effective against all coronavirus variants as well as influenza viruses. Markovitz and the team hope to see the therapy take the more difficult step from animal models to testing in humans. The team envisions a nasal spray or drops that can be used to prevent or treat coronavirus and influenza infections in seasonal and pandemic situations. They also hope to examine using H84T-BanLec against cancer—as cancer cells, like viruses, also have high mannose glycans on their surfaces.

Additional authors include Yoo Jin Oh, Shuofeng Yuan , Hin Chu , Man-Lung Yeung , Daniel Canena , Chris Chung-Sing Chan, Vincent Kwok-Man Poon, Chris ChunYiu Chan, Anna Jinxia Zhang, Jian-Piao Cai , Zi-Wei Ye , Lei Wen, Terrence Tsz-Tai Yuen, Kenn Ka-Heng Chik, Huiping Shuai, Yixin Wang, Yuxin Hou, Cuiting Luo, WanMui Chan, Zhenzhi Qin, Ko-Yung Sit, Wing-Kuk Au, Maureen Legendre, Rong Zhu, Lisa Hain , Hannah Seferovic, Robert Tampé, Kelvin Kai-Wang To, Kwok-Hung Chan, Dafydd Gareth Thomas, Miriam Klausberger, Cheng Xu , James J. Moon, Johannes Stadlmann, Josef M. Penninger, and Chris Oostenbrink. Thomas, Xu, Moon and Legendre are all from the University of Michigan.

Live your healthiest life: Get tips from top experts weekly. Subscribe to the Michigan Health blog newsletter

Headlines from the frontlines: The power of scientific discovery harnessed and delivered to your inbox every week. Subscribe to the Michigan Health Lab blog newsletter

Like Podcasts? Add the Michigan Medicine News Break on Spotify, Apple Podcasts or anywhere you listen to podcasts.

Paper cited: "A Molecularly Engineered, Broad-spectrum Anti-coronavirus 2 Lectin Inhibits SARS-CoV-2 and MERS-CoV Infection In Vivo," Cell Reports Medicine. DOI: 10.1016/j.xcrm.2022.100774


More Articles About: Lab Report All Research Topics Community Health Future Think Covid-19 Immunizations COVID-19 Vaccine Hospitals & Centers infectious disease
Health Lab word mark overlaying blue cells
Health Lab

Explore a variety of healthcare news & stories by visiting the Health Lab home page for more articles.

Media Contact Public Relations

Department of Communication at Michigan Medicine

[email protected]

734-764-2220

Stay Informed

Want top health & research news weekly? Sign up for Health Lab’s newsletters today!

Subscribe
Featured News & Stories Mott Poll teens and caffeine
Health Lab
Does your teen consume too much caffeine?
A quarter of parents report that caffeine is basically part of their teen’s daily life, according to a national poll.
pills floating blue pink dark background physician in middle looking at chart white coat scrubs
Health Lab
Better medical record-keeping needed to fight antibiotic overuse, studies suggest
Efforts to reduce overuse of antibiotics may be hampered by incomplete medical records that don’t show the full reasons for prescriptions.
zoom screens with 7 different backgrounds and doctor silhouettes outlined in each
Health Lab
The doctor is in…. but what’s behind them?
A study reveals that what a doctor has behind them during a telehealth visit can make a difference in how the patient feels about them and their care.
surgery gloves passing tool blue and yellow
Health Lab
A universal heparin reversal drug is shown effective in mice
The newest version of the heparin reversal drug, described in a recent issue of Advanced Healthcare Materials, adjusted the number of protons bound to it, making the molecule less positive so it would preferentially bind to the highly negative heparin, resulting in a much safer drug.
blue gloves in hospital hanging IV bag
Health Lab
Commonly used antibiotic brings more complications, death in the sickest patients
In emergency rooms and intensive care units across the country, clinicians make split-second decisions about which antibiotics to give a patient when a life threatening infection is suspected. Now, a study reveals that these decisions may have unintended consequences for patient outcomes.
A graphic of the brain
News Release
University of Michigan researchers receive Javits Award for work on stroke health disparities in Mexican Americans
Two University of Michigan researchers have received the Javits Neuroscience Investigator Award from the National Institute of Neurological Disorders and Stroke for their work on stroke health disparities in Mexican Americans. The $5 million in funding allows the Texas-based research project to reach a 32-year milestone and expand to 35-to-44-year-olds whose incidence of stroke is increasing.