Identifying mutant peptides from heat-shock protein 70, for treatment of cancer

摘要

Identifying peptides (I), derived from heat-shock protein 70 (hsp70) that stimulate a tumor-specific T cell response is new.- DETAILED DESCRIPTION - Identifying (I) from heat-shock protein 70 (hsp70), that - (1) have at least one mutation or alteration compared with the native sequence, and - (2) induce a tumor-specific T-cell response, the method comprising: - (i) amplifying hsp70-encoding DNA from one or more tumors; - (ii) cloning in a vector that can be replicated in bacteria; - (iii) sequencing fragments in each cultured bacterial colony to identify any hsp70 mutations, and - (iv) determining the immunogenicity of the mutant peptides identified.- INDEPENDENT CLAIMS are also included for the following: - (a) detecting artificial point mutations or alterations that increase immunogenicity of mutated (I) by identifying 9-10 amino acid (aa) fragments that include a motif for anchorage to a selected HLA (human leucocyte antigen) molecule, introducing an additional mutation at positions 4-8 and determining immunogenicity of the products; - (b) (I) containing at least 8 consecutive aa from hsp70; - (c) DNA fragments (II) that encode (I); - (d) expression vector containing (II) fused to strong promoter functional in eukaryotic and/or prokaryotic, especially human, cells; - (e) dendritic cells loaded with (I) or transformed with the vector of (d); - (f) composition containing (I), vectors of (d), (II) or cells of (e) plus a vehicle; - (g) combined preparation comprising (I) and an agent (III) that induces cellular stress, for simultaneous, separate or staged use for treatment of cancer; - (h) production of antibodies (Ab) that bind to hsp70 mutants, specifically the hsp70-2-I-293 mutant, by immunizing animals with (I); - (i) monoclonal Ab; - (j) detecting mutant hsp70 using Ab; - (k) kits containing Ab for diagnosis and prognosis of cancer; and - (l) a composition containing Ab and a vehicle.- ACTIVITY - Anticancer.- MECHANISM OF ACTION - (I) induce a specific T cell immune response against tumor and break tolerance to the native form of hsp70