Tomatine adjuvantation of protective immunity to a major pre-erythrocytic vaccine candidate of malaria is mediated via CD8+ T cell release of IFN-gamma.

Abstract

The glycoalkaloid tomatine, derived from the wild tomato, can act as a powerful adjuvant to elicit an antigen-specific cell-mediated immune response to the circumsporozoite (CS) protein, a major pre-erythrocytic stage malaria vaccine candidate antigen. Using a defined MHC-class-I-restricted CS epitope in a Plasmodium berghei rodent model, antigen-specific cytotoxic T lymphocyte activity and IFN-gamma secretion ex vivo were both significantly enhanced compared to responses detected from similarly stimulated splenocytes from naive and tomatine-saline-immunized mice. Further, through lymphocyte depletion it is demonstrated that antigen-specific IFN-gamma is produced exclusively by the CD8(+) T cell subset. We conclude that the processing of the P. berghei CS peptide as an exogenous antigen and its presentation via MHC class I molecules to CD8(+) T cells leads to an immune response that is an in vitro correlate of protection against pre-erythrocytic malaria. Further characterization of tomatine as an adjuvant in malaria vaccine development is indicated.

• Authors: Karen G Heal, Andrew W Taylor-Robinson
• Journal: Journal of biomedicine & biotechnology (J Biomed Biotechnol) Vol. 2010 Pg. 834326 ( 2010) ISSN: 1110-7251 [Electronic] United States
• PMID: 20300588 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Adjuvants, Immunologic
• Cytokines
• Tomatine
• Interferon-gamma

Topics

• Adjuvants, Immunologic (administration & dosage)
• Animals
• CD8-Positive T-Lymphocytes (drug effects, immunology)
• Cells, Cultured
• Cytokines (immunology)
• Dose-Response Relationship, Drug
• Immunity, Innate (drug effects, immunology)
• Interferon-gamma
• Malaria (immunology, prevention & control)
• Mice
• Tomatine (administration & dosage)