“…Nevertheless, only a very limited set of the SLA class I molecules have been well documented and reported ( Zhang N. et al, 2011 ; Fan et al, 2016 ), and the characteristics of peptide presentation for SLA class I molecules and cellular immune mechanisms have remained elusive until now. The structure and function of SLA class I complexes constructed in vitro are currently used to simulate the functions of SLA class I molecules in vivo and numerous in vitro SLA class I complexes have been constructed and different peptide–SLA-I binding assays have been suggested ( Oleksiewicz et al, 2002 ; Sylvester-Hvid et al, 2002 ; Gao et al, 2006 ; Pedersen et al, 2011 ; Zhang N. et al, 2011 ; Gao et al, 2012 ; Fan et al, 2016 ). A relative simple and rapid, in vitro refolding enzyme-linked immunosorbent assay (ELISA)-based method was able to discriminate between peptide-occupied and peptide-free SLA-I complexes based on monoclonal antibody PT85A binding ( Oleksiewicz et al, 2002 ), because the PT85A monoclonal antibody can recognize all SLA class I molecules, from outbred as well as inbred pigs, and the conformational epitope was recognized by PT85A, required the presence of the ‘correct’ peptide as well as the ‘correct’ SLA class I molecule sequence ( Lunney, 1994 ; Davis et al, 2000 ; Mosaad et al, 2006 ).…”