homology searches in protein data banks revealed the presence of the peptide sdgr in the alpha 2 domain of mhc class i antigens , and a variant of rgds , arg-phe-asp-ser ( rfds ) , was found highly conserved in mhc class i ( alpha 1 domain ) and class ii antigens ( beta 1 domain ) .
C0019629
mhc class i antigens
C0017355
mhc class i