Measles: Can we use a human baby vaccine for veterinary purposes?
Phanramphoei Namprachan Frantz1,2
1Virology and Antibody Technology Research Unit, National Center for Genetic Engineering and Biotechnology, NSTDA, Thailand
2Viral Genomic and Vaccination Unit, Institut Pasteur, CNRS UMR 3569, Paris, France
Abstract:
The measles (MV) vaccine is an efficient, live attenuated, replicating virus that has been safely administered to over 1 billion children over the last 40 years, affording life-long protection after a single dose. Taking advantage of these characteristics, this attenuated virus was transformed into a versatile chimeric or recombinant vaccine vector (rMV) with demonstrated proof-of-principle in humans and a preclinical track record of rapid adaptability and effectiveness for a variety of pathogens. One of the reasons that the rMV vaccine is very effective without an influence from pre-existing immunity might be due to the presence of high level of 5' copy-back defective interfering genomes (DI-RNAs). These RNAs strongly stimulate type-I interferon via recognition by RIG-I-like receptors (RLRs), therefore playing the role of an adjuvant. Therefore, it is possible that the MV vector can be used to stimulate a specific immune response in animals through the same mechanism. We show that rMV-GFP is able to replicate in some animal cell lines although viral spreading is limited. In vivo, we show that while rMV-luciferase cannot replicate in WT mice, antibodies to MV antigens are detected at the same level compared to that of interferon-α/β receptor defective (IFNAR-/-) mice in which the virus strongly replicates. Thus the inability to replicate well in animals does not interfere with the induction of MV specific antibodies. Moreover, co-immunization of the spike protein (S) of Porcine Epidemic Diarrhea Virus (PEDV) with recombinant MV carrying the same S antigen in normal C57BL/6 mice showed higher anti-S specific immune response when compared to that of mice immunized with alum adjuvanted protein. This suggests the potential use of the MV vector as a vaccine candidate against animal diseases.