FIG. 1.

Mouse-adapted EV71 grows more rapidly and is more cytotoxic than the parental strain. (A) One-step growth curves of the parental EV71 strain Tainan/4643/98 and the mouse-adapted strain MP4 in RD, SK-N-SH, and Caco-2 cells were determined as described in Materials and Methods. (B) SK-N-SH cells (2 × 10⁴) grown in 96-well plates were infected with 4643 or MP4, and cell viability was determined at the times indicated. Data represent the means ± SEM of results of three independent experiments performed in triplicate (A) and of two experiments with eight duplicates (B). *, P < 0.05.