RT Journal Article SR Electronic(1) A1 Deblanc, Céline A1 Delgado-Ortega, Mario A1 Gorin, Stéphane A1 Berri, Mustapha A1 Paboeuf, Frédéric A1 Berthon, Patricia A1 Herrler, Georg A1 Meurens, François A1 Simon, GaëlleYR 2016 T1 Mycoplasma hyopneumoniae does not affect the interferon-related anti-viral response but predisposes the pig to a higher level of inflammation following swine influenza virus infection JF Journal of General Virology, VO 97 IS 10 SP 2501 OP 2515 DO https://doi.org/10.1099/jgv.0.000573 PB Microbiology Society, SN 1465-2099, AB In pigs, influenza A viruses and Mycoplasma hyopneumoniae (Mhp) are major contributors to the porcine respiratory disease complex. Pre-infection with Mhp was previously shown experimentally to exacerbate the clinical outcomes of H1N1 infection during the first week after virus inoculation. In order to better understand the interactions between these pathogens, we aimed to assess very early responses (at 5, 24 and 48 h) after H1N1 infection in pigs pre-infected or not with Mhp. Clinical signs and macroscopic lung lesions were similar in both infected groups at early times post-H1N1 infection; and Mhp pre-infection affected neither the influenza virus replication nor the IFN-induced antiviral responses in the lung. However, it predisposed the animals to a higher inflammatory response to H1N1 infection, as revealed by the massive infiltration of neutrophils and macrophages into the lungs and the increased production of pro-inflammatory cytokines (IL-6, IL-1β and TNF-α). Thus, it seems it is this marked inflammatory state that would play a role in exacerbating the clinical signs subsequent to H1N1 infection., UL https://www.microbiologyresearch.org/content/journal/jgv/10.1099/jgv.0.000573