New Antivirals Produced From Bananas Able To Fight Deadly Flu And Might Also Combat Other Viruses Including Coronaviruses.
Source: Thailand Medical News Jan 22, 2020 6 years, 3 weeks, 4 days, 2 hours, 22 minutes ago
Unknown to most common people, what keeps most infectious disease researchers busy are not infamous
viruses like Ebola. Instead,the
influenza virus, commonly known as the
flu, continues to be a clear and present danger to humanity.
Dr David Markovitz, M.D., Professor of internal medicine in the division of infectious diseases at Michigan Medicine told
Thailand Medical News, "
Influenza is a huge problem, as the
virus sickens or kills millions of people each year. A new pandemic along the lines of the 1918 Spanish
flu has the potential to kill millions here and abroad."
According to WHO and US CDC, more than 640,000 people worldwide died from the
flu virus in the 2018 seasons.
Dr David Markovitz and an extensive team of collaborators have worked for years on broad-spectrum
antiviral drugs developed from, of all things,
bananas.
A recent research paper published in the
Proceedings of the National Academy of Sciences, by Dr Markovitz, first author Dr Evelyn Coves-Datson, a M.D., Ph.D. student, Dr Akira Ono, Ph.D., professor of microbiology and immunology and their team have shown that an engineered compound based on a
banana lectin, a protein called
H84T, has real potential for clinical use against
influenza.
In research experiments, more than 80% of mice exposed to a form of
influenza that is typically fatal were able to survive the disease after receiving an injection of the protein, even up to 72 hours after exposure.
The research team also provides early evidence that the compound is safe. A downside of naturally occurring
banana lectin, which can cause inflammation by inappropriately activating the immune system wasn't present in mice given
H84T.
Furthermore, because
H84T is a protein, there was concern that the body would recognize it as foreign and develop antibodies against it, thereby neutralizing it or causing harm. The team found that while mice did develop antibodies against
H84T, they didn't appear to be adversely affected by them.
The new compound works because it targets a sugar called high mannose, which is present on the outside of certain
viruses but not on most healthy cells. "We were able to show that
H84T blocks the ability of the
influenza virus to fuse with structures termed endosomes in the human cell, a key step in infection," he explains. Doing so disabled their ability to replicate and wreak havoc.
Significantly, this mechanism of action, binding of high mannose sugars on the surface of
viruses, means that
H84T is effective not only against
influenza, but also against Ebola, HIV, measles, MERS, a new deadly viral illness that was first reported in Saudi Arabia in 2012, SARS and all other
ref="https://www.thailandmedical.news/">coronaviruses tested.
What is more promising is that the compound works where
Tamiflu (
oseltamivir), the current standard therapy for severe flu, has failed. "We've also shown that there may be a synergistic effect between
H84T and
Tamiflu," says Dr Markovitz.
The research team hopes to do more research with the compound in humans in the hopes of getting it to market. "We envision the government potentially stockpiling it in the event of a pandemic." However, he says, "there are many difficulties to commercialization. Pharmaceutical economics do not seem to favor the development of
antivirals or antibacterials for one-time usage, which is a huge problem."
Reference : A molecularly engineered antiviral banana lectin inhibits fusion and is efficacious against influenza virus infection in vivo. Proceedings of the National Academy of Sciences. DOI: 10.1073/pnas.191515211 
