Israeli scientists discover how to reverse cell ageing
A team of scientists has found why elderly people are more susceptible to COVID-19 and are working to reverse the ageing process of the body’s immune system
Professor Doron Melamed (right) and Dr. Reem Dowery
(photo credit: NITZAN ZOHAR/TECHNION SPOKESPERSON'S OFFICE)
Scientists from the Technion-Israel Institute of Technology say they have found a way to rejuvenate the ageing process of the body’s immune system.
Prof.
Doron Melamed and doctoral student Reem Dowery sought to understand why
the elderly population is more susceptible to severe cases of COVID-19
and why the vaccines seem to be less effective and wane faster among
this population.
The results of their work were published this month in the peer-reviewed, online medical journal Blood.
The secret begins with B cells, also known as B lymphocytes. These are the cells that produce antibodies against any pathogen that enters the body. They play a key role in protecting people from viruses and disease.
The secret begins with B cells, also known as B lymphocytes. These are the cells that produce antibodies against any pathogen that enters the body. They play a key role in protecting people from viruses and disease.
B cells are produced in bone marrow and then travel through the
blood to lymph nodes and the spleen, where they wait for pathogens to
enter and then attack them.
“When
you are young, you have young cells, and young cells have a very
diverse ability to recognize anything [pathogenic] that comes into your
body,” Melamed told The Jerusalem Post.
B
cells do not live long, but they are constantly being replenished by
new ones sent from the bone marrow, creating what Melamed calls
“homeostasis,” a state in which the total number of B cells in the bone
marrow and outside remains constant.
However,
B cells do not just disappear. They turn into “memory” B cells so that
if the body is exposed to a previous pathogen, the individual will not
get sick. That is because the immune response will be fast and robust,
and it will eliminate the pathogen, often without the individual knowing
he or she had been exposed to it.
Unlike B cells, memory cells are long-lived.
“Imagine
you are growing into adulthood, and you become an adult and then an
older person,”
Melamed said. “You accumulate in your body many memory
cells. You are exposed all the time to pathogens, and hence you make
more and more memory cells. Because these are so long-lived, there is no
room left for new B cells.”
What happens when a new pathogen, such as the coronavirus, comes along? There are no young B cells that can recognize it.
That is one of the reasons why older people are more susceptible to severe COVID-19 and many other diseases.
As noted, this happens because of the body’s need for homeostasis, something that Melamed’s lab discovered a decade ago.
BUT THIS year, they took the discovery another step and figured out a mechanism to override the system.
“We
found specific hormonal signals produced by the old B cells, the memory
cells, that inhibit the bone marrow from producing new B cells,”
Melamed said. “This is a huge discovery. It is like finding a needle in a
haystack.”
It
also means that, over time, specific drugs or treatments can be found to
inhibit one of the hormones in the signalling pathway and get the bone
marrow to produce new B cells.
Melamed Research group (credit: NITZAN ZOHAR/TECHNION SPOKESPERSON'S OFFICE)What happens when a new pathogen, such as the coronavirus, comes along? There are no young B cells that can recognise it.
That is one of the reasons why older people are more susceptible to severe COVID-19 and many other diseases.
As noted, this happens because of the body’s need for homeostasis, something that Melamed’s lab discovered a decade ago.
BUT THIS year, they took the discovery another step and figured out a mechanism to override the system.
“We found specific hormonal signals produced by the old B cells, the memory cells, that inhibit the bone marrow from producing new B cells,” Melamed said. “This is a huge discovery. It is like finding a needle in a haystack.”
It
also means that, over time, specific drugs or treatments can be found to
inhibit one of the hormones in the signaling pathway and get the bone
marrow to produce new B cells.
To validate their theory, Melamed’s lab collaborated with the departments of hematology and rheumatology at Sourasky Medical Center
in Tel Aviv and Rambam Health Care Campus in Haifa. As part of
treatment for some medical conditions, such as lupus, lymphoma and
multiple sclerosis, patients undergo B cell depletion, meaning a
significant amount of memory B cells is removed from their bodies.
Examining
older patients who underwent this procedure, the group found that their
immune systems rejuvenated, and their bodies could produce new B cells
again.
An effect
similar to B cell depletion can be produced by inhibiting one of the
hormones in the signalling pathway that suppresses the production of new B
cells.
“Now we
understand that there is some kind of conversation between compartments
in the body, between how B cells are produced and what controls that,”
Melamed said.
In
the interim, he recommended that doctors use this knowledge to protect
the elderly better, such as by instituting a vaccination program
targeted just for the adult population that preempts variants with an
additional shot.
“Even every three or four months, vaccinate them again and again to ensure they maintain high antibodies,” Melamed said.
Please Recommend this page and follow us at:
He
also suggested mixing vaccines, such as combining a shot of a Pfizer
mRNA vaccine with an AstraZeneca booster given several months later,
“which may generate better stimulation of the elderly immune system.”
At
the same time, clinical trials would be needed to determine how to
safely inhibit the hormones to find a longer-term solution, hopefully
before the next pandemic, Melamed said.
No comments:
Post a Comment
Stick to the subject, NO religion, or Party politics