In the classical paradigm of immunological tolerance, the majority of Tregs develop within the thymus upon presentation of MHCII epitopes from mTECs and medullary DCs. Does this mean that if a protein in the periphery doesn't have an MHCII epitope, then it can't be tolerized against?
Can an protein be tolerized against if it doesn't have an MHCII epitope?
Posted 04 March 2014 - 05:25 PM
Tolerance can be induced against a protein without MHCII. T cells undergo positive selection in the thymus in that they only survive when they bind strongly enough to MHC I or MHC II (CD8 and CD4 positive T cells respectively), and negative selection in that they only survive when they do not bind strongly to the self-antigens ectopically expressed by mTECs and DCs. IIRC T regs are supposed to have an intermediate affinity here, although I'm not sure if this is just a theory or already proven.
Il dort. Quoique le sort fût pour lui bien étrange,
Il vivait. Il mourut quand il n'eut plus son ange;
La chose simplement d'elle-même arriva,
Comme la nuit se fait lorsque le jour s'en va.