FIG 4.
Mutations in the E′F′ loop of the MNV-1 P domain mediate escape from MAb A6.2 neutralization in mice. STAT1−/− mice were simultaneously infected with 106 PFU of the indicated recombinant MNV-1 orally and injected with MAb A6.2 (open box) or isotype control MAb (black box) intraperitoneally. Virus titers were measured 48 h postinfection in indicated tissues from animals infected with the wild type (A) or one of the Q298E (B), S299A (C), A382K (D), A382R (E), or L386F (F) mutants with 500 μg MAb, WT-infected animals injected with 15 (G) and 100 (H) μg MAb, and L386F mutant-infected animals injected with 15 (I) and 100 (J) μg MAb, respectively. Data are presented as means ± standard deviations (SD) from at least five mice per condition from at least two independent experiments. Statistical analysis was performed using the t test to compare the virus titer for each tissue between MAb A6.2-injected mice and the isotype control. *, P < 0.05; **, P < 0.01; ***, P < 0.001.