In article <199909222135.SM00432@[216.1.197.45]>, Jay and Nancy Mone
<URL:mailto:jaymone at PAONLINE.COM> wrote:
> The short answer goes like this:
>> During T cell ontogeny, T cells undergo selection in the thymus. As
> thymic cells present self antigens to young T cells, any T cell which can
> respond to those antigens begins down a biochemical pathway that leads to
> cell death. In this way, autoimmune responses are avoided without
> compromising the ability to respond to foreign antigens. What is meant
> by self antigen is an antigen produced by your own body. Since no T
> cells are present which can react to self antigens, these antigens are
> tolerated (hence the name tolerance).
>> Jay M
>
The above answer is one which is used to teach the concepts of self
non-self discrimination at a very basic level. It's an approximation to the
truth but is in reality flawed.
There are many good (and unfortunately many bad) text books which deal with
this issue. If you read accounts in several text books then you may start
to appreciate the complexity of the question asked.
Text books I tend to recommend to my own students in no particular order
are
Immunobiology by Janeway and Travers
Immunology by Janice Kuby
Advanced Immunology by Male et al
If you prefer to do your research on the internet then you could go to the
Deja News website and search for previous immunological discussions on
Tolerance, Self non-self and also Danger, Non-Danger.
It all depends how complex an answer you want!
There is an important element of 'Snake Oil' in a blind belief that the
immune system functions by merely learning all self and then reacting to
everything else.
Mike <URL:http://www.path.cam.ac.uk/~mrc7/>
--
o/ \\ // || ,_ o M.R. Clark, PhD. Division of Immunology
<\__,\\ // __o || / /\, Cambridge University, Dept. Pathology
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