Fig. 4From: Tween-20 transiently changes the surface morphology of PK-15 cells and improves PCV2 infectionEffect of 0.03% Tween-20 on the viability of PCV2-infected PK-15 cells. Cell viability was determined by using an MTT assay at the indicated post treatment times. The percentage of relative cell viability is expressed as themean ± SD (n = 3). Within each time point, values with different letters (a, b) are significantly different from each other (p < 0.01)Back to article page