AN ACCESSORY PEPTIDE BINDING-SITE WITH ALLOSTERIC EFFECT ON THE FORMATION OF PEPTIDE-MHC-II COMPLEXES

MHC-II molecules bind a single peptide in their groove. Here, the auth ors summarise evidence that a second peptide could bind transiently to MHC-II molecules outside the groove and have an allosteric effect on peptide-MHC-II complex formation. This effect could modulate, after th e antigen processing, the selection of the peptide subset presented by MHC-II molecules to the helper CD4 T cells, which regulate the specif ic immune response. ((C) Academie des sciences/Elsevier, Paris.).