The Influence of Porcine Reproductive and Respiratory Syndrome Virus Infection on the Expression of Cellular Prion Protein in Marc-145 Cells
Cellular prion protein (PrPC) represents a potential regulator of cellular immunity and has been confirmed to be an invasive receptor exploited by bacteria such as Brucella abortus to facilitate the infection in host cells. Up to now, there are few informations about the role of PrPC in virus replication in host cells. Porcine reproductive and respiratory syndrome virus (PRRSV), a single positive-stranded RNA virus, prefers to infect African green monkey kidney cell line MA-104 and its derivatives, such as Marc-145. We found that PrPC is expressed on the surfaces of Marc-145 cells and its expression profiles greatly changed after PRRSV incubation with these cells. PrPC expression reached the peak at 12 hrs after PRRSV inoculation and then decreased sharply to recover to the original status while CD163, a PRRSV receptor in Marc-145 cells, achieved the climax at 48 hrs after virus infection and then slowly lowered its expression level. Here, we firstly suggest that PRRSV infection has an influence on the expression of PrPC on the surfaces of Marc-145 cells and PrPC may be involved in PRRSV invasion of host cells.