Fig. 2

AS-ON was present in cell culture six hours post transfection. Cy3-labelled antisense oligonucleotide 5UP2 (32 μM) was used in the transfection in Marc-145 cells. The fluorescent signals were recorded with fluorescence microscopy (Olympus) at various time points post transfection. Cells are shown to the left and the merged images (cells with fluorescent oligonucleotides) to the right. Although fluorescent signals decreased over the time, we could still clearly observe the signals even six hours post transfection, indicating that the antisense oligonucleotide persist in Marc-145 cells for sufficiently long time periods to induce the degradation of viral RNA and to inhibit PRRSV replication