PMID: 25642819

 

    Legend: Sugar

Title : αβ T cell antigen receptor recognition of CD1a presenting self lipid ligands

Abstract :
  1. A central paradigm in αβ T cell-mediated immunity is the simultaneous co-recognition of antigens and antigen-presenting molecules by the αβ T cell antigen receptor ( TCR )
  2. CD1a presents a broad repertoire of lipid-based antigens
  3. We found that a prototypical autoreactive TCR bound CD1a when it was presenting a series of permissive endogenous ligands, while othe r lipid ligands were nonpermissive to TCR binding
  4. The structures of two TCR- CD1a-lipid complexes showed that the TCR docked ove r the A' roof of CD1a in a manne r that precluded direct contact with permissive ligands
  5. Nonpermissive ligands indirectly inhibited TCR binding by disrupting the TCR- CD1a contact zone
  6. The exclusive r ecognition of CD1a by the TCR represents a previously unknown mechanism whereby αβ T cells indirectly sense self antigens that are bound to an antigen-presenting molecule