Then, cells were incubated with 3HP-β-LG at a final concentration of 15 μg/ml at 0.5 h before or 0, 0.5, 1, 2, 4, 8, 12, 24, and 48 h after addition of HPV PsV (equal to 36 ng L1), followed by an incubation at 37°C for 16 h.