Figure 2.

Blocking COX-1 or COX-2 activity by specific inhibitors, or by siRNAs targeting COX-2 mRNA reduce MHV infection. (A) Caco-MHVR cells were incubated with COX-1 (SC-560; 1 μM) or COX-2 (NS-398; 0.055 μM) inhibitor 1 h prior to inoculation with MHV-A59 (m.o.i. = 0.01) and were maintained in the presence of the inhibitors until they were fixed. The numbers of MHV-infected cells were determined with an indirect IFA and are presented as described in the legend of Figure 1. (B) HeLa cells were transfected with 10 nM siRNAs, targeting the indicated transcripts, 72 h prior to inoculation with MHV-FLSrec. Cell viability was measured for 30 minutes at 6 h p.i. using a WST-1 assay as described previously [37], after which the intracellular luciferase levels were determined as relative light units (RLU). Luciferase levels in siRNA-transfected cells are expressed as a percentage of the levels in the mock-transfected (control) cells and were corrected for the percentage of viable cells (n = 3).