Inflammatory response in PAMs induced by PRRSV 5′UTR RNA and LPS. A, B PAMs were transfected with different doses of 5′UTR RNA (1, 2, and 4 μg/well) along with 1 μg/mL LPS. qRT-PCR and Western blot results showed that compared with PAMs in other groups, PAMs in the 4 μg 5′UTR RNA and 1 μg/mL LPS co-stimulation group produced higher levels of IL-1β (p < 0.05). C After co-stimulation, the relative expression level of IL-1β mRNA obtained was similar at the 12 and 24 h time-points. D 5′UTR RNA and LPS co-stimulation induced IL-1β expression in cells and supernatants. E, F 5′UTR RNA and LPS co-stimulation induced increased levels of IL-6, IL-8 and TNF-α mRNA and protein. Expression was normalized to that of GAPDH. Different letters (a, b, c, d, and e) on data indicate significant differences between groups (p < 0.05).