Immune Complex Proteomes: Tools for Vaccine Discovery

Abstract

World-wide in tropical and subtropical areas, approximately 200 million cases of malaria are reported annually with about 1 million deaths occurring in children under the age of 5 years. Data from proteomic studies are providing new strategies for identifying Plasmodium falciparum proteins with malaria vaccine and therapeutic potential. Purified native and recombinant proteins, and heterogeneous mixtures of proteins have been used traditionally for proteome analysis using 2-D gel electrophoresis (2DE) followed by the identification and excision of differential protein spots stained on sodium dodecyl sulfatepolyacrylamide (SDS-PAGE) gels and analysis by mass spectrometry. The use of antibodies to add specificity to the identification of proteins analyzed by proteomics provides a practical benefit in small scale studies, in small laboratory settings, to identify changes in protein expression observed in normal and pathogenic states in humans. Antibodies can also be used to identify stage specific and developmental changes occurring in parasitic infections and in identifying expressed proteins of parasite origin present in human serum. The need for additional levels of specificity in protein identification was recognized in the initial reports of protein identification by sequencing followed by database searches for unambiguous identification of correct proteins [1]. The use of antibodies; either unlabeled or tagged to capture antigens followed by mass spectrometry