A Bacterially-Expressed Recombinant Envelope Protein from Usutu Virus Induces Neutralizing Antibodies in Rabbits

Vaccines, vol. 9, pp. 157

Abstract

BACKGROUND: Recently, an emerging flavivirus, Usutu virus (USUV), has caused an epidemic among birds in Europe, resulting in a massive die-off in Eurasian blackbirds. Currently found only in Europe and Africa, it can be envisioned that Usutu virus will follow the path of other flaviviruses, like West Nile virus and Zika virus, and will spread via its mosquito vectors and bird hosts to other parts of the world. Several cases of human infections by Usutu virus have already been published. Anticipating this spread, development of an efficacious vaccine would be highly desirable. METHOD: , purification, and refolding of a partial USUV envelope protein. Prior to immunization, the protein was characterized using size exclusion chromatography, transmission electron microscopy and dynamic light scattering, showing the limited presence of virus-like structures, indicating that the protein solution is probably a mixture of mono and multimeric envelope proteins. RESULTS: Immunizations of two rabbits with the refolded E-protein fraction, mixed with a strong adjuvant, resulted in the generation of neutralizing antibodies, as evidenced in an in vitro assay. DISCUSSION: The way forward towards a subunit vaccine against Usutu virus infection is discussed.

Authors 17

1. Kinga P. Böszörményi corresponding

   Biomedical Primate Research Centre

   Affiliation as printed

   Department of Virology, Biomedical Primate Research Centre, Lange Kleiweg 161, 2288 GJ Rijswijk, The Netherlands

2. Janet Hirsch

   HAW Hamburg

   Affiliation as printed

   Department of Biotechnology, Hamburg University of Applied Sciences, Ulmenliet 20, 21033 Hamburg, Germany

3. Gwendoline Kiemenyi Kayere

   Biomedical Primate Research Centre

   Affiliation as printed

   Department of Virology, Biomedical Primate Research Centre, Lange Kleiweg 161, 2288 GJ Rijswijk, The Netherlands

4. Zahra C. Fagrouch

   Biomedical Primate Research Centre

   Affiliation as printed

   Department of Virology, Biomedical Primate Research Centre, Lange Kleiweg 161, 2288 GJ Rijswijk, The Netherlands

5. Nicole Heijmans

   Biomedical Primate Research Centre

   Affiliation as printed

   Department of Parasitology, Biomedical Primate Research Centre, Lange Kleiweg 161, 2288 GJ Rijswijk, The Netherlands

6. Soesjiel Dwarka

   Biomedical Primate Research Centre

   Affiliation as printed

   Department of Parasitology, Biomedical Primate Research Centre, Lange Kleiweg 161, 2288 GJ Rijswijk, The Netherlands

7. Amy van Dijke

   Biomedical Primate Research Centre

   Affiliation as printed

   Department of Parasitology, Biomedical Primate Research Centre, Lange Kleiweg 161, 2288 GJ Rijswijk, The Netherlands

8. Boyd Aaldijk

   Biomedical Primate Research Centre

   Affiliation as printed

   Department of Parasitology, Biomedical Primate Research Centre, Lange Kleiweg 161, 2288 GJ Rijswijk, The Netherlands

9. Ronald W.A.L. Limpens Aachen Section Electron Microscopy

   Leiden University Medical Center

   Affiliation as printed

   Section Electron Microscopy, Leiden University Medical Center, Einthovenweg 20, 2300 RC Leiden, The Netherlands

10. Montserrat Bárcena Aachen Section Electron Microscopy

    Leiden University Medical Center

    Affiliation as printed

    Section Electron Microscopy, Leiden University Medical Center, Einthovenweg 20, 2300 RC Leiden, The Netherlands

11. Bram Koster Aachen Section Electron Microscopy

    Leiden University Medical Center

    Affiliation as printed

    Section Electron Microscopy, Leiden University Medical Center, Einthovenweg 20, 2300 RC Leiden, The Netherlands

12. Babs E. Verstrepen

    Biomedical Primate Research Centre

    Affiliation as printed

    Department of Virology, Biomedical Primate Research Centre, Lange Kleiweg 161, 2288 GJ Rijswijk, The Netherlands

13. Willy M J M Bogers

    Biomedical Primate Research Centre

    Affiliation as printed

    Department of Virology, Biomedical Primate Research Centre, Lange Kleiweg 161, 2288 GJ Rijswijk, The Netherlands

14. Clemens H. M. Kocken

    Biomedical Primate Research Centre

    Affiliation as printed

    Department of Parasitology, Biomedical Primate Research Centre, Lange Kleiweg 161, 2288 GJ Rijswijk, The Netherlands

15. Gesine Cornellissen

    HAW Hamburg

    Affiliation as printed

    Department of Biotechnology, Hamburg University of Applied Sciences, Ulmenliet 20, 21033 Hamburg, Germany

16. Ernst J. Verschoor

    Biomedical Primate Research Centre

    Affiliation as printed

    Department of Virology, Biomedical Primate Research Centre, Lange Kleiweg 161, 2288 GJ Rijswijk, The Netherlands

17. Bart W. Faber corresponding

    Biomedical Primate Research Centre

    Affiliation as printed

    Department of Parasitology, Biomedical Primate Research Centre, Lange Kleiweg 161, 2288 GJ Rijswijk, The Netherlands