Page 85 - The Miracle in the Immune System

Bacteria
Bacteria
Antibody
B is man-
Antigen
ufac-
Antibody A is
tured in
manufactured in
order to
order to fit anti-
fit anti-
gen A
gen B
The anti antibody in
The anti antibody in the blood
the blood

antibody binds to antigen on the
surface of the bacteria and renders it ineffective.
Antibody B would
not fit antigen A

Bacteria and viruses carry
chemicals on their surfaces Antibodies with different antigens
called antigens. Some lym- cannot be effective against bacteria.
phocytes produce antibod-
ies to bind themselves to
antigens, thus enabling the
white cell to easily ingest the
bacteria. Antibodies have
distinct features and they
only bind to antigens for
which they are produced. As
Antibody A would not
illustrated in the above pic-
fit antigen B
ture, a triangular antigen
perfectly fits to an antibody,
which has a triangular cut.
(top left). Yet the same anti-
body (bottom) does not fit to
a round antigen.