Chicken and duck myotubes are highly susceptible and permissive to influenza virus infection.
Bottom Line: Besides its primary function in movement and posture, skeletal muscle is a significant innate immune organ with the capacity to produce cytokines and chemokines and respond to proinflammatory cytokines.Infected chicken myotubes produced significantly higher levels of proinflammatory cytokines than did the corresponding duck cells.Our results indicate that avian skeletal muscle fibers of chicken and duck could be significant contributors to progeny production of highly pathogenic H5N1 viruses.
Affiliation: School of Veterinary Medicine and Science, University of Nottingham, Loughborough, Leicestershire, United Kingdom.Show MeSH
Related in: MedlinePlus
Mentions: The intracellular and extracellular accumulation of viral M gene RNA was determined in duck myotube, duck myoblast, and MDCK cell cultures infected with LPAI H2N3 virus at a MOI of 0.1. At 6 h, 12 h, and 24 h p.i., duck myotubes produced significantly higher levels(P < 0.005) of intracellular viral M gene RNA than did similarly infected myoblasts and MDCK cells (Fig. 2A). Similar results were obtained with the corresponding chicken myotubes (data not shown). Viral M gene RNA in culture supernatants of duck myotubes at 24 h p.i., as assessed by one-step reverse transcription real-time PCR, was significantly more abundant than in the other two cell types (Fig. 2B). Taken together, these results suggest that the viral replication rate was higher in avian myotubes than in mononuclear cells. Since myoblasts and myotubes from both avian species as well as MDCK cells expressed both the human and avian influenza receptor types (α-2,6-linked sialic acid and α-2,3-linked sialic acid, respectively) (Fig. 2C), it is likely that the observed relatively high viral expression levels of M gene RNA and NP protein in myotubes were not due to differences in the early stages of virus receptor binding and virus entry.
Affiliation: School of Veterinary Medicine and Science, University of Nottingham, Loughborough, Leicestershire, United Kingdom.