Quantitative gel-based proteomics (2D DIGE coupled to MALDI-TOF/TOF MS) has been used to investigate the effects of different measles virus (MV) strains on the host cell
proteome. A549/hSLAM cells were infected either with wild type MV strains, an
attenuated vaccine or a multiple passaged Vero cell adapted strain. By including
interferon beta treatment as a control it was possible to distinguish between the classical
antiviral response and changes induced specifically by the different strains. Of 38 differentially expressed
proteins in total (p-value ≤0.05, fold change ≥2), 18
proteins were uniquely modulated following MV
infection with up to 9
proteins specific per individual strain. Interestingly, wt strains displayed distinct
protein patterns particularly during the late phase of
infection.
Proteins were grouped into cytoskeleton, metabolism, transcription/translation, immune response and
mitochondrial proteins. Bioinformatics analysis revealed mostly changes in
proteins regulating cell death and apoptosis. Surprisingly, wt strains affected the
cytokeratin system much stronger than the
vaccine strain. To our knowledge, this is the first study on the MV-host
proteome addressing interstrain differences.
BIOLOGICAL SIGNIFICANCE: In the present study we investigated the host cell
proteome upon measles virus (MV)
infection. The novelty about this study is the side-by side comparison of different strains from the same virus, which has not been done at the
proteome level for any other virus including MV. We used different virus strains including a
vaccine strain, wild type isolates derived from MV-infected patients as well as a Vero cell adapted strain, which serves as an intermediate between
vaccine and wild type strain. We observed differences between
vaccine and wild type strains as well as common features between different wild type strains. Perhaps one of the most surprising findings was that differences did not only occur between wild type and
vaccine or Vero cell adapted strains but also between different wild type strains. In fact our study suggests that besides the
cytokeratin and the IFN system wild type viruses seem to differ as much among each other than from
vaccine strains. Thus our results are suggestive of complex and diverse virus-host interactions which differ considerably between different wild type strains. Our data indicate that interstrain differences are prominent and have so far been neglected by proteomics studies.