Quantitative RT-PCR (qRT-PCR)
Total RNAs from tissues were extracted with RNAiso Plus (Takara) according to the manufacturer’s instructions. Reverse transcriptions were completed using a PrimeScriptTM RT reagent Kit (Takara). qRT-PCR was performed by using a SYBR Green qPCR Kit (Takara, CN) in the Applied Biosystems 7500 Fast Real-Time PCR System (Life Technologies). PEDV load was determined by detecting the viral nucleocapsid (N) gene (Fwd: 5’-CACCTCCTGCTTCACGTACA-3’ and Rev:5’-AGCTCCACGACCCTGGTTAT-3’). The glyceraldehyde 3-phosphate dehydrogenase (GAPDH, Fwd: 5’-TCATCATCTCTGCCCCTTCT-3’ and Rev: 5’- GTCATGAGTCCCTCCACGAT-3’) was used as the reference gene. The relative levels of viral RNA were calculated by using the 2-ΔΔCT method.