Fig. 2.

Virus titers during serial virus passages. a Vero cells were infected with either MP-12 vaccine Lot-7-2-88 or rMP12-ΔNSs16/198 at MOI of 0.01 (two separate passage experiments under the same conditions: Exp-1 and 2). At 3 dpi, culture supernatants were collected, and 0.1 μl was used for the next passage in Vero cells (5 × 10⁵ cells). Virus titers in culture supernatants at 3 dpi of passages 1, 5, 10, 15, 20, and 25 are shown in a graph. b Similarly, MRC-5 cells were infected with MP-12 vaccine Lot-7-2-88 (three separate passage experiments under the same conditions: Exp-1, 2, and 3), and virus titers were measured at passages 1, 5, 10, 15, 20, and 25