Immunogenic control of tumours and tumour cells
The present invention relates to the use of immunogenic peptides comprising a T-cell epitope derived from a tumour-associated antigen and a redox motif such as C-(X)2-[CST] or [CST]-(X)2-C in the treatment of a tumour or in the treatment or prevention of a tumour relapse, and in the manufacture of medicaments therefore.
1. A method of treating a tumor expressing a tumor associated antigen or of treating a relapse of a tumor expressing a tumor associated antigen comprising the step of administering, an immunogenic fusion peptide consisting of between 13 and 50 amino acids, comprising (i) an MHC Class II restricted T-cell epitope consisting of 8 or 9 amino acids of said tumor-associated antigen and (ii) a reducing C-(X)2-C motif, wherein X is not cysteine, which motif is separated from said T-cell epitope by a linker consisting of 1 or 2 amino acids.
2. The method of claim 1 , wherein said treatment induces CD4+ T cells which are cytotoxic to cells presenting said tumor-associated antigen.
3. The method according to claim 1 wherein said tumor-associated antigen is an oncogene, a proto-oncogene, a viral protein, a surviving factor or a clonotypic determinant.
4. The method according to claim 1 wherein said immunogenic peptide further comprises an endosomal targeting sequence.
5. The method according to claim 1 wherein said C-(X)2-C motif is positioned N-terminally of the T-cell epitope.
6. The method according to claim 1 wherein at least one X in said C-(X)2-C motif is Gly, Ala, Ser or Thr.
7. The method according to claim 1 wherein at least one X in said C-(X)2-C motif is His or Pro.
8. The method according to claim 1 wherein at least one C in said C-(X)2-C motif is methylated.
9. The method according to claim 1 wherein said immunogenic peptide is produced by chemical synthesis or by recombinant expression.