Do you or anyone else know though if the signals that upregulate B7
expression will be present if self-peptide is in the groove? But then I
guess that comes back to the question of how the macrophage differentiates
between self and non-self. Any thoughts?
-Rachel
On 6 Nov 1994, Ian A. York wrote:
> In article <Pine.3.07.9411051900.A21700-c100000 at alsys1> teitelba at aecom.yu.edu (Rachel Teitelbaum) writes:
> >I think it might be worthwhile to mention anergy here too. Even if a self
> >peptide is preseted, odds are a second costimulation through alternate
> >receptors (other than the TCR, eg CD28) are not supplied and the immune
> >system is tolerized to that antigen.
>>> Do you mean in the thymus, or in the periphery? If the former, I
> agree with you; but if you mean that presentation of self-antigen is
> different in any way from presentation of foreign antigen, I don't
> agree. After all, the same macrophage that presents foreign antigen is
> simultaneously presenting self antigen, albeit on different MHC
> molecules (which may or may not be derived from the same allele). I
> can't imagine that the macrophage will give the second signal to a
> lymphocyte with a foreign-epitope-specific TcR, yet coyly snatch away the
> signals from the self-reactive TcR. If the lymphocyte is unable to
> recognize the second signal, that's a different matter, and I had meant to
> include that in the differentiation at the level of the T cell.
> Sorry if I misunderstand your comment.
>> Ian
> --
> Ian York (york at mbcrr.harvard.edu)
> Dana-Farber Cancer Institute, 44 Binney St., Boston MA 02115
> Phone (617)-632-4328 Fax (617)-632-2627
>>
