Use of reconstituted influenza virus virosomes as an immunopotentiating delivery system for a peptide-based vaccine

Abstract

Immunopotentiating reconstituted influenza virosomes (IRIV) were used as a delivery system for the synthetic peptide-based malaria vaccine SPf66. The reduced SPf66 peptide molecules containing terminal cysteine residues were covalently attached to phosphatidylethanolamine with the heterobifunctional crosslinker gamma-maleimidobutyric acid N-hydroxysuccinimide ester. The SPf66-phosphatidylethanolamine was incorporated into IRIV and BALB/c mice were immunized twice by intramuscular injection with peptide-loaded virosomes. Titres of elicited anti-SPf66 IgG were determined by ELISA. These titres were significantly higher and the required doses of antigen were lower, when mice had been preimmunized with a commercial whole virus influenza vaccine. After preimmunization with the influenza vaccine, SPf66-IRIV elicited far more consistently anti-SPf66 antibody responses than SPf(66)n adsorbed to alum. MoAb produced by four B cell hybridoma clones derived from a SPf66-IRIV-immunized mouse cross-reacted with Plasmodium falciparum blood stage parasites in immunofluorescence assays. All four MoAbs were specific for the merozoite surface protein-1 (MSP-1)-derived 83.1 portion of SPf66. Sequencing of their functionally rearranged kappa light chain variable region genes demonstrated that the four hybridomas were generated from clonally related splenic B cells. Biomolecular interaction analyses (BIA) together with these sequencing data provided evidence for the selection of somatically mutated affinity-matured B cells upon repeated immunization with SPf66-IRIV. The results indicate that IRIV are a suitable delivery system for synthetic peptide vaccines and thus have a great potential for the design of molecularly defined combined vaccines targeted against multiple antigens and development stages of one parasite, as well as against multiple pathogens.

Induction of Parasite Growth-Inhibitory Antibodies by a Virosomal Formulation of a Peptidomimetic of Loop I from Domain III of Plasmodium falciparum Apical Membrane Antigen 1

“…In an attempt to overcome both problems, we are evaluating the use of a human-compatible delivery system comprising IRIVs in synthetic peptide vaccine design (28,34). IRIVs are spherical, unilammelar vesicles prepared by detergent removal from a mixture of natural and synthetic phospholipids and influenza virus surface glycoproteins.…”

New age adjuvants and delivery systems for subunit vaccines

“…The reported antibody titres were significantly higher and the required dose of antigen was lower, when mice had been pre-immunized with a commercial whole virus influenza vaccine. These results indicate that IRIV is a suitable delivery system for synthetic peptide vaccines and thus have great potential for the design of molecularly defined combined vaccines targeted against multiple antigens and developmental stages of the same parasite, as well as against multiple pathogens (29).…”

“…The F1 antigen, one of the protective anigens of Y. pestis, when entrapped in liposomes and immunized in mice of different haplotypes induced very high antibody titres as compared to F1 antigen adsorbed onto alum (29). This approach provided an opportunity to delineate the major and minor antigenic determinants on F1 antigen (25).…”

Assessing nanoparticle toxicity in cell-based assays: influence of cell culture parameters and optimized models for bridging the in vitro–in vivo gap

“…Nanotechnology itself can subsequently be described as the manipulation and application of particles and systems with at least one dimension below 100 nm 10 . For nanomedicine purposes these technologies are being used to develop applications for diagnosis 12,13 , imaging 14,15 , treatment 16,17 and prevention of diseases [18][19][20] . One of the latest developments in nanomedicine are theranostic particles, which combine imaging or diagnostic and therapeutic features in a single construct 21,22 .…”