CEF19, Epstein-Barr Virus latent NA-3A (458-466), is a peptide epitope, YPLHEQHGM, representing residues 458-466 of the type 1 Epstein-Barr Virus (EBV) nuclear antigen 3A protein (B95.8 strain).
CEF6, a HLA-B7 restricted influenza virus nucleoprotein epitope, belongs to the CEF control peptides. The CEF control peptides are 8-12 amino acids in length, with sequences derived from the human cytomegalovirus, Epstein-Barr virus and influenza virus.