INCREASING THE IMMUNOGENICITY OF PROTEIN ANTIGENS THROUGH THE GENETICINSERTION OF VQGEESNDK SEQUENCE OF HUMAN IL-1-BETA INTO THEIR SEQUENCE

The immunogenicity of two recombinant protein Ag containing the immuno stimulatory sequence of human IL-1beta 163-1 71 (VQGEESNDK) geneticall y engineered into their structure has been evaluated. The IL-1beta seq uence was inserted into the loop between alpha helices D and E of reco mbinant human ferritin H chain and into the hypervariable region of re combinant flagellin from Salmonella muenchen. The chimeric proteins we re injected into mice and the level of humoral immune response develop ed against the native proteins was assessed by measuring the number of Ag-specific plaque forming cells/spleen or as the level of serum IgG response. The response was compared to that of mice receiving injectio ns with wild-type protein Ag not containing the VQGEESNDK sequence or with hybrid constructs containing unrelated foreign peptide sequences of the same length. A significantly higher immune response was observe d in mice immunized with chimeric constructs containing the human IL-1 beta 163-171 sequence. These data suggest that the insertion of the VQ GEESNDK sequence may prove useful to increase the immune response agai nst poorly immunogenic recombinant proteins.