Fig 4. Inhibition of COX isoforms results in a dramatic reduction in feline calicivirus (FCV) progeny yield.

(A–F) CRFK cells were pretreated (Pre), post-treated (Post), or pre-post-treated (Pre-Post) with non-cytotoxic doses of SC-560, NS-398, and indomethacin. At 8 h post-infection (hpi) with FCV (MOI, 1 FFU/cell), the viral titer and genome copy number were determined by TCID₅₀/ml and quantitative real time PCR (qRT-PCR). The inhibitory effects of each drug on virus titer or genome copy number were compared between mock- and drug-treated groups. (G and H) COX-1, COX-2, or scrambled (Scram) siRNAs were transfected in CRFK cells before infection with FCV (MOI, 1 FFU/cell). The samples were harvested at 8 hpi, and then the viral titer and genome copy number were determined by TCID₅₀/ml (G) and qRT-PCR (H) analyses. Three independent experiments were conducted and presented as means and standard errors of the mean. Statistical differences were determined using one-way analysis of variance. *p < 0.05; **p < 0.001; ***p < 0.0001.