Fig. 4

LPS pre-incubation on EV-A71 attachment and internalization. RD cells were treated with 0.1 ng/mL to 10 μg/mL LPS for 0 to 12 h followed by cell viability assessment using CCK8 (a). 2 MOI of EV-A71 were pre-incubated with 200 ng/mL or 500 ng/mL LPS at 37 °C for 2 h, then the virus were used to infect RD cells with binding buffer on ice. 1 h later, the cells were washed (attachment assessment) or/and cultured at 37 °C for another 1 h and then treated with trypsin (internalization assessment). Viral RNA was extracted by commercial kit and EV-A71 RNA was determined by qPCR (b). Data were showed as M ± SD and student’s t test was used for comparisons, n.s. > 0.05, *P < 0.05, **P < 0.01