ejf at welchlink.welch.jhu.edu
Sat Jul 16 06:22:40 EST 1994
Please help me with this question:
One of the cardinal features of the immune system is its ability to
discriminate self from nonself. Recent experimental evidence suggests
that a two signal model of lymphocyte activation is the biological basis
for S/NS discrimination. For CD4+ T cells, signal two is delivered by
the antigen presenting cell.
Here is the question:
Since antigen presenting cells take in antigens randomly from their
environment, how is their delivery of signal two regulated so as to
achieve a self/nonself discrimination?
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