Western blot analysis of human and pig sera using porcine cytomegalovirus (PCMV) proteins as antigens. (a) SDS-PAGE and Coomassie blue staining of purified recombinant PCMV-derived proteins: R1, N-terminal part of gB, R2, C-terminal part of gB, UA, tegument protein U54A, UB, tegument protein U54B, M, marker proteins; (b) Western blot analysis using antibodies against the His-tag, pig serum 2994, human sera 6331 and 9858. Antibodies were used at the following dilutions: anti-His antibodies 1:1000, pig serum 2994 1:300, human sera 6331 and 9858 were used 1:300, anti-mouse serum 1:1000, anti-human serum 1:1000, and anti-pig serum 1:1000.