The intracellular model with in- and efflux of siRNA and virions. (A-C) low Dicer cleavage rate (5 cleavages per Dicer per hour); (D-F) intermediate Dicer cleavage rate (15 cleavages per Dicer per hour). (A) and (D) time-series for the intracellular model without in and efflux (black) and with efflux (red). (B) and (D) Time-series with in- and efflux showing bistability: low siRNA influx (black lines) results in a high equilibrium, high siRNA influx (red lines) in a low equilibrium. (C) and (F) Bifurcation diagram showing equilibrium values of viral plus-strand RNA for increasing siRNA influx. The different lines are calculated with a fixed virion influx measured for the different patterns in Figure 3. ΔSi in (C) from left to right lines: 5% (black), 8% (red), 10% (green); and in (F) from left to right: 0.5% (black), 2% (red), 4% (green), 5% (blue). Circles indicate the position of cells that reached the high and the low equilibrium in the tissue model.