Possibility of autologous tumor-derived heat shock protein as a tumor vaccine for cancer immunotherapy

Adjuvant-free vaccination with tumor-derived heat shock protein (HSP)- peptide complex has been previously shown to elicit tumor-specific protective and therapeutic immunity in murine systems. We investigated the in vitro effect of hsp70 preparations purified from surgically resected human colon cancer on autologous and allogeneic peripheral blood mononuclear cells (PBMC). The secretion of a considerable amount of TNF-α and INF-γ was observed both in autologous and allogeneic PBMC, while the proliferative response and tumor-specific cytotoxic activity were induced only in autologous PBMC. These results suggest that autologous tumor-derived HSP may not only serve as a nonspecific adjuvant but also act as a specific tumor vaccine for cancer immunotherapy.