The antigenicity profile methods are based on the assumption that specific physicochemical profiles of sequences side chains, invariably corresponds with immunodominant regions of protein. Different groups have used different scales to define the antigenic potential profile along the protein sequence e.g. inverted hydrophobicity scales, scales of turns, Flexibility scales etc. The algorithms are mainly available in the form of commercial (PeptideStructure and PepPlot of GCG, Protean module of DNAstar) or freeware packages (EMBOSS, ProWin) etc.