Potential therapies extracted from banana protein are effective against SARS-CoV-2

On January 13, 2020, a paper was published online touting the creation of a possible therapy that could be used to fight all known flu strains
.
A week later, the first laboratory-confirmed case of SARS-CoV-2 triggered a two-and-a-half-year COVID-19 pandemic
in the United States.
Interestingly, before the virus temporarily halted their work, the international research team of this flu paper also investigated a cure
for the coronavirus.

"At the time we thought MERS would be a big target because its 35 percent mortality rate worried us," said
David Markovitz, MD, a professor of internal medicine in the Division of Infectious Diseases at the University of Michigan School of Medicine.

A paper in Cell Reports Medicine details the efficacy of H84T-BanLec for all known human coronaviruses, including Middle East respiratory syndrome (MERS), the original SARS, and SARS-Cov2 (including the omicron variant).

。 Markovitz was joined in the study by two senior authors, Dr.
Peter Hinterdorfer of the Institute of Biophysics at Johannes Kepler University and Kwok-Yung Yuen
, MD, MBBS of the University of Hong Kong.
The first author of the paper is Jasper Fuk-Woo Chan
, MD, of the University of Hong Kong.

"When COVID-19 happened, we certainly wanted to study the potential of this therapy and find that it was effective
for every type of coronavirus in vitro and in vivo," Markovitz said.
It is effective
either as a systemic injection or through the nose in an animal model, or as a prophylaxis or treatment early in the disease.
”

H84T-BanLec is lectin (a carbohydrate-binding protein)
isolated from banana fruit.
It achieves its remarkable virus-blocking ability by binding to high-mannose glycans, a polysaccharide found on the surface of the virus but rarely on normal, healthy human cells
.
After binding, the virus cannot enter the cells to infect them
.
Using atomic force microscopy and related methods, the team confirmed that H84T forms multiple strong bonds with the spike protein, which Markovitz says may explain why the coronavirus has so much trouble fighting lectins
.

Markovitz explained that despite the antiviral potential of lectins, they have traditionally been avoided as a possible treatment because they are a protein
that can stimulate the immune system in harmful ways.
However, H84T-BanLec was modified to eliminate this effect and showed no harmful effects
in animal models.

While there are currently several medications for the treatment of COVID-19, including remdesivir, parovide, and monoclonal antibodies, their effectiveness, side effects, and ease of use vary, and many have been shown to be less effective as SARS-CoV2 continues to
evolve.

According to the team, H84T-BanLec has unique prospects because it is effective against
all coronavirus variants and influenza viruses.
Markowitz and his team hope to see this therapy take a tougher step
from animal models to human trials.
The team envisioned a nasal spray or drop that could be used to prevent or treat coronavirus and flu infections
in seasonal and pandemic situations.
They also hope to study the use of H84T-BanLec to fight cancer, because cancer cells, like viruses, have a large amount of mannan on their surface
.