PFOS mediates immunomodulation in an avian cell line that can be mitigated via a virus infection

Background Per- and polyfluoroalkyl substances (PFASs) are environmentally persistent and bioaccumulative chemicals. Immunomodulation is among the most concerning of toxic effects linked with PFAS exposure in mammalian models. However, no studies had yet shown this to be true in birds. Thus, we designed and conducted the first study to determine if PFASs could cause immunomodulation in birds. Secondly, we wanted to determine the effects on an avian host when exposed not only to immunomodulating chemicals, but also to a viral challenge. The aim, to determine if PFAS mediated immunmodulation functionally affects a pathogen challenge for a host. As innate immune system signalling pathways initiate crucial responses against a pathogen challenge, and are lesser studied than their adaptive counterparts, we focused on these pathways. To provide the first information on this, an in vitro experiment was designed and performed using chicken embryo fibroblasts exposed to perfluorooctane sulfonate (PFOS) (22 ppm) and immune markers characterised before and after being infected with gallid herpesvirus-2 (GaHV-2).