Page 71 - The Miracle of the Immune System

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Cells on Duty in the System

extremely important: this information will later be used in the manufac-
ture of antibodies.
The transformation of B cells rapidly goes on. Upon an order coming
from an unknown source, cells produce proteins called "alfa" and "beta",
which surround the cell membrane. At a further level, a range of compli-
cated processes are due to take place in the cell to enable it to produce
some molecules that will enable it to bind to antigens. At the end of all

these complicated operations, the cells turn into a factory that recognizes
the enemy as soon as it makes contact with it, and is able produce millions
of different weapons.

Can Every B Cell That Has Been Manufactured
Stay Alive?

The more we delve into the details of the defence system, the more
miracles we encounter. As stated before, B cells manufacture antibodies.
Antibodies are weapons that are manufactured purely to cause harm to
enemy cells. So, what happens if the weapons produced by the B cell con-

fuse their targets and start to hit friendly cells?
In that case, the other cells send a signal inside the B cell. This signal
is actually an order for the cell to "commit suicide". Eventually, some en-
zymes in the nucleus of the cell are activated and they decompose the
DNA of the cell. A perfectly working auto-control mechanism protects the
body, and finally, only the B cells that produce antibodies that cause harm
to the enemy can stay alive.
Only comprised of a compact nucleus and very little cytoplasm ini-
tially, the B cells undergo unbelievable changes when they meet an anti-
gen. They divide repeatedly and build up thousands of assembly points in
their cytoplasm for the manufacture of antibodies, as well as an extensive

channeling system for the packaging and exporting the antibodies. One B
cell can pump out more than 10 million antibody molecules an hour.
Here is a single cell that transforms itself into a factory competent