AUTHOR=König Enrico , Gagliardi Assunta , Riedmiller Ilary , Andretta Chiara , Tomasi Michele , Irene Carmela , Frattini Luca , Zanella Ilaria , Berti Francesco , Grandi Alberto , Caproni Elena , Fantappiè Laura , Grandi Guido TITLE=Multi-Antigen Outer Membrane Vesicle Engineering to Develop Polyvalent Vaccines: The Staphylococcus aureus Case JOURNAL=Frontiers in Immunology VOLUME=12 YEAR=2021 URL=https://www.frontiersin.org/journals/immunology/articles/10.3389/fimmu.2021.752168 DOI=10.3389/fimmu.2021.752168 ISSN=1664-3224 ABSTRACT=
Modification of surface antigens and differential expression of virulence factors are frequent strategies pathogens adopt to escape the host immune system. These escape mechanisms make pathogens a “moving target” for our immune system and represent a challenge for the development of vaccines, which require more than one antigen to be efficacious. Therefore, the availability of strategies, which simplify vaccine design, is highly desirable. Bacterial Outer Membrane Vesicles (OMVs) are a promising vaccine platform for their built-in adjuvanticity, ease of purification and flexibility to be engineered with foreign proteins. However, data on if and how OMVs can be engineered with multiple antigens is limited. In this work, we report a multi-antigen expression strategy based on the co-expression of two chimeras, each constituted by head-to-tail fusions of immunogenic proteins, in the same OMV-producing strain. We tested the strategy to develop a vaccine against