The invention relates to a method for the antigen-specific stimulation of T-lymphocytes with a synthetic peptide library, by preparing a plurality of peptides, each of said peptides comprising a fragment less than the whole of the total amino acid sequence of the antigen, each of said peptides being a minimum of 9 amino acid residues (AAs) in length, and the amino acid sequence of each peptide overlapping with the amino acid sequence of at least one other of said peptides; combining a plurality of the peptides from a) into a peptide library, said peptide library comprises a plurality of the peptides selected such that their collective overlapping amino acid sequences span the total amino acid sequence of the antigen; and incubating a suspension comprising CD8+ T lymphocytes, CD4+ T lymphocytes or a mixture of CD8+ and CD4+ with said peptide library in a single culture run.