We have attempted finding common sequential patterns among protein antigens. For this, we have used Gibbs multiple motif sampler on the set of all non-redundant antigenic sequences available in curated databanks. Several sequential motifs are obtained on these sequences when the amino acids are represented according to their similarity clusters. Significantly high proportions of known B-cell epitope sites are found within or adjacent to these motifs, thus indicating a possibility of linear epitope signatures. These findings may offer important applications in synthesis of peptide vaccines. A predictive example in this regard is presented.