Secondary Immune Response
Name: Michael W.
Date: December 2002
What is the "secondary immune response"?
When your body first meets with an antigen (something it does not "recognize"
and is capable of stimulating a response) it mounts an attack. This is a
very complicated set of reactions that has many check and balances and
eventually results in the destruction of the antigen. This process initially
takes some time. Some of the cells that are made in this process stick
around to become what are known as memory cells. These have already been
"taught" what the antigen looks like and retain this memory throughout your
life. If that antigen ever comes back these memory cells are ready and
waiting and destroy the antigen before your body even has a chance to know it
was there. Another word for the secondary response is the "anamnestic"
response, which means "without forgetting". (think of the word "amnesia")
With an healthy individual, a primary immune response takes place when an antigen (foreign protein)
is detected by one of an array of white blood cells. After a series of rather amazing series
of processes includes the development of antibodies against the antigen, the pathagen is either
destroyed or rendered incapable of injuring cells. This usually takes
7-14 days to complete. One aspect of this process is the production of 2 kinds of memory cells
that can act rather quickly if the same type of antigen appears in the future. If this occurs, it is termed
a secondary immune response. Since most of the processes of developing antigens has already been
determined the first time, the secondary immune response can complete the antibody, etc. development
in 2-6 days.
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Update: June 2012