Figure 4. Selected SPMs increase antiviral host defence.
In hosts infected with influenza viruses, endogenous protectin D1 production is increased. Protectin D1 limits influenza pathogenicity by directly interacting with the RNA replication machinery to inhibit viral RNA nuclear export. In particularly virulent strains of influenza, such as the H5N1 avian (A) strain, protectin D1 formation is not sufficiently upregulated, leading to more efficient viral replication and host demise. Treatment of the host with exogenous protectin D1 can restore inhibition of viral RNA export, thereby limiting viral replication and improving host survival.