News Release

Publication of scientific paper on the identification of multi-HLA reactive epitope peptide derived from HSP70

It is known that HSP70(Heat Shock Protein 70) is highly expressed in many cancers. In this paper, twenty-nine HSP70-derived 9mer peptides were predicted as multi-HLA-class I reactive epitope peptides by the MHC-binding peptide prediction system of NEC Corporation, where six peptides were confirmed to bind to all of HLA-A*24:02, 02:01, and 02:06 alleles with binding assay conducted at Kochi University. Finally, a peptide was identified to induce specific CTLs exhibiting antitumor activity for those multiple HLAs with ex vivo tests using HCC patients’ blood conducted at Yamaguchi University. It was also noted in the paper that the identified peptide had a lower binding affinity than other HLA binding peptides, suggesting that it could be a Cryptic peptide for which various T cell repertoire escaped from central immune tolerance and retained antitumor activity. This peptide is used in CYT001.
Matsui H. et al, Identification of a Promiscuous Epitope Peptide Derived from HSP70, Immunother, 2019, 42(7): 244-250
DOI:10.1097/CJI.0000000000000274 (https://www.ncbi.nlm.nih.gov/pubmed/31398179)