Heme oxygenase-1 acts as an antiviral factor for porcine reproductive and respiratory syndrome virus infection and over-expression inhibits virus replication in vitro.

Virus replication depends upon host-cell processes in infected cells, and this is true for porcine reproductive and respiratory syndrome virus (PRRSV), the causative agent of PRRS that is a worldwide threat to the swine industry. Heme oxygenase-1 (HO-1) is a ubiquitously expressed inducible isoform of the first and rate-limiting enzyme for heme degradation. Our previous research suggested that HO-1 may play an important role in PRRSV infection.