Overlapping peptides from variable antigens, t cell populations and uses thereof

A set of overlapping peptides of an antigen, said antigen being a variable antigen, comprising:

• a) a first sub-set of peptides longer than 10 amino acids consisting of conserved sequence regions between an amino acid sequence of a variant antigen and the consensus amino acid sequence of said variable antigen, and
• b) a second sub-set of peptides, each peptide being between 10 and 19 amino acids long and containing an amino acid sequence of said variant antigen that differs for at least one amino acid residue from the consensus amino acid sequence of said variable antigen, and optionally one or more immunodominant region and/or a optimal epitope region or portions thereof at its N or C terminus, wherein each of said peptides does not have as the last C-terminal amino acid any of the following amino acids:
• Asn, Asp, Gln, Glu, Gly, His, Ser;
• wherein each peptide of the first sub-set and of the second sub-set of peptides has a gap not longer than 8 amino acids with its closest overlapping peptide.