Heat Shock Proteins and Their Use as Anticancer Vaccines

Abstract
Many tumor-associated antigens (TAAs) are now available in the form of single peptide epitopes restricted by known HLA class I or II alleles (see ref. 2 ). However, all of the TAAs used in clinical protocols belonged to the group of normal (i.e., self) peptides/proteins (e.g., gp100, tyrosinase, CEA) shown to be weakly immunogenic in vivo. This may be one important reason for the limited clinical response rate observed in these studies, in addition to mechanisms of immune evasion, which have been reported previously (3) .