No Antibodies Required For Immunity Against Some Viruses

No Antibodies Required For Immunity Against Some Viruses






A new study turns the well established theory that antibodies are
required for antiviral immunity upside down and reveals that an
unexpected partnership between the specific and non-specific divisions
of the immune system is critical for fighting some types of viral
infections. The research, published online in the journal Immunity
by Cell Press, may lead to a new understanding of the best way to help
protect those exposed to potentially lethal viruses, such as the rabies virus.

The immune system has two main branches, innate immunity and adaptive
immunity. Innate immunity is a first line of defense that relies on
cells and mechanisms that provide non-specific immunity. The more
sophisticated adaptive immunity, which counts antibody-producing B cells
as part of its arsenal, is thought to play a major role in the
specific response to viral infections in mammals. However, adaptive
immune responses require time to become fully mobilized.

"Mice infected with vesicular stomatitis virus (VSV) can suffer fatal
invasion of the central nervous system even when they have a high
concentration of anti-VSV antibodies in their system," explains senior
study author, Dr. Ulrich H. von Andrian, from Harvard Medical School.
"This observation led us to revisit the contribution of adaptive immune
responses to survival following VSV infection."

The research team studied VSV infection in mice that had B cells but did
not produce antibodies. Unexpectedly, although the B cells themselves
were essential, survival after VSV exposure did not require antibodies
or other aspects of traditional adaptive immunity."We determined that
the B cells produced a chemical needed to maintain innate immune cells
called macrophages. The macrophages produced type I interferons, which
were required to prevent fatal VSV invasion," says co-author Dr. Matteo
Iannacone.

Taken together, the results show that the essential role of B cells
against VSV does not require adaptive mechanisms, but is instead
directly linked with the innate immune system. "Our findings contradict
the current view that antibodies are absolutely required to survive
infection with viruses like VSV, and establish an unexpected function
for B cells as custodians of macrophages in antiviral immunity,"
concludes Dr. von Andrian. "It will be important to further dissect the
role of antibodies and interferons in immunity against similar viruses
that attack the nervous system, such as rabies, West Nile virus, and Encephalitis."



Source:-
http://www.medicalnewstoday.com/releases/242403.php

Hello,

Here you provide some information about Innate immunity.
It is a truly amazing constellation of responses to attacks from outside
the body, which can change to optimize the response. These system is
remarkably effective, most of the time. I like the way you start and
then conclude your thoughts. Thanks for this information....

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