The placental protein syncytin-1 impairs antiviral responses and exaggerates inflammatory responses to influenza

Pregnancy increases susceptibility to influenza. The placenta releases an immunosuppressive endogenous retroviral protein syncytin-1. We hypothesised that exposure of peripheral monocytes (PBMCs) to syncytin-1 would impair responses to H1N1pdm09 influenza.

Our data indicates that a placental derived protein, syncytin-1 may be responsible for the heightened vulnerability of pregnant women to influenza.