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Showing posts with the label viral interference

Prior #influenza virus #infection alleviates an #arbovirus #encephalitis by reducing viral titer, #inflammation, and cellular infiltrates in the central nervous system

ABSTRACT Respiratory and encephalitic virus infections represent a significant risk to public health globally . Detailed investigations of immunological responses and disease outcomes during sequential virus infections are rare. Here, we define the impact of influenza virus infection on a subsequent virus encephalitis . We used a model system in which mice were given influenza A virus (IAV) infection 8 days prior to Semliki Forest virus (SFV) infection (IAV→SFV). IAV infection clearly attenuated the subsequent SFV infection with reduced titers of infectious SFV and lower levels of cytokines and chemokines in the central nervous system ( CNS ). In contrast, the SFV viremia in both IAV→SFV and SFV-only mice was comparable. Increased type I interferon (IFN) levels in the CNS after IAV infection might have contributed to some level of protection towards SFV infection in the CNS, suggesting that early control of SFV replication in the CNS during IAV→SFV infection led to reduced adaptive res...

Respiratory Virus-Specific and #Time-Dependent #Interference of #Adenovirus Type 2, #SARS-CoV-2 and #Influenza Virus #H1N1pdm09 During Viral Dual Co-Infection and Superinfection In Vitro

Abstract Background .  Understanding the interference patterns of respiratory viruses could be important for shedding light on potential strategies to combat these human infectious agents.  Objective .  To investigate the possible interactions between adenovirus type 2 (AdV2), severe acute respiratory syndrome coronavirus 2 ( SARS-CoV-2 ) and influenza A/H1N1 pandemic (H1N1pdm09) using the A549 cell line .  Methods .  Single infections, co-infections, and superinfections (at 3 and 24 h after the first virus infection) were performed by varying the multiplicity of infection (MOI). Virus replication kinetics and the mRNA expression of IFN-α, IL-1α and IL-6 were assessed by real-time qPCR.  Results .  Co-infection experiments showed different growth dynamics , depending on the presence of the specific virus and time. AdV2 replication remained stable or possibly enhanced in the presence of co-infection with each of the two H1N1pdm09 and SARS-CoV-2 viruses ...