TABLE 3.
Y98F mutant induces protective immune response equivalent to that for WT virus
| Virus inoculuma | Postinfection serum HI antibody GMTb | Lung viral titer (log10 PFU/ml) at day 3 postchallengec |
|---|---|---|
| WT virus | 126 | <1.3 |
| Y98F virus | 112 | <1.3 |
| None | <10 | 5.8 |
Groups of mice were infected i.n. with 106 PFU of WT or Y98F mutant virus or were mock infected with virus diluent.
Three months postinfection, sera from three or four mice per group were collected and tested individually for the presence of HI antibody. Data are expressed as the geometric mean titer (GMT). A value of <10 represents the lower limit of antibody detection.
Three months postinfection, mice were challenged with 106 PFU of WT virus; 3 days later, animals were euthanized, lungs from three or four mice per group were collected and pooled, and titers were determined to assess the presence of virus on MDCK cells. The lower limit of virus detection was 101.3 PFU/ml.