Antigen Cross-Presentation and Heat Shock Protein-Based Vaccines

Vaccines currently in the clinical use contain adjuvants stimulating preferably Th2 type of immune response associated with the production of specific antibodies, mostly of neutralizing isotypes. This kind of immune response is effective only against some types of pathogens and has limited effect against tumors and many viruses where parallel activation of antigen-specific humoral and cell-mediated immunity is required. One of the main objectives of the current vaccine research is the development of approaches leading to the induction of antigen-specific CD8+ T cell response including cytotoxic T lymphocyte (CTL). Induction of antigen-specific CD8+ T cell response to exogenously delivered antigen requires their cross-presentation by antigen presenting cells, especially dendritic cells. The cross-presentation principles seem to be crucial for effective activation of CTL. In this paper, we discuss some approaches to employing heat shock proteins for induction of antigen-specific CD8+ T cells in the context of cross-presentation and cross-priming principles.