TABLE 2.
Neurovirulence for suckling mice of ChimeriVax-JE viruses with and without a mutation at E279 and of YF 17D vaccine
| Expt | Mouse age (days) | Virus, passage, and E279 amino acid | i.c. dose (log10 PFU) | Mortality (%) | Avg survival time (days) | LD50 (log10 PFU) |
|---|---|---|---|---|---|---|
| 1 | 8.6 | YF-VAX | 1.15 | 10/10 (100) | 8.4 | 0.11 |
| 0.15 | 5/10 (50) | 10 | ||||
| −0.85 | 1/10 (10) | 14 | ||||
| ChimeriVax-JE, FRhL3, E279 Met | 2.60 | 1/10 (10) | 15 | >2.6 | ||
| 1.6 | 1/10 (10) | 13 | ||||
| 0.6 | 0/10 (0) | NAa | ||||
| −0.45 | 0/10 (0) | NA | ||||
| ChimeriVax-JE, FRhL5, E279 Lys | 3.0 | 10/10 (100) | 10.3 | 1.64 | ||
| 2.0 | 8/10 (80) | 11.25 | ||||
| 1.0 | 2/10 (20) | 14.5 | ||||
| 0 | 2/10 (20) | 16 | ||||
| 2 | 4 | YF-VAX | 0.95 | 11/11 (100) | 8.4 | −0.3 |
| −0.05 | 9/11 (82) | 8.8 | ||||
| −1.05 | 2/12 (17) | 10 | ||||
| ChimeriVax-JE, FRhL3, E279 Met | 2.69 | 7/12 (58) | 10.6 | 2.5 | ||
| 1.69 | 4/12 (33) | 11.5 | ||||
| 0.69 | 0/12 (0) | NA | ||||
| ChimeriVax-JE, FRhL5, E279 Lys | 2.88 | 10/12 (83) | 9.3 | 1.45 | ||
| 1.88 | 11/12 (92) | 10.3 | ||||
| 0.88 | 4/12 (33) | 12.2 | ||||
| −0.11 | 2/12 (17) | 14 | ||||
| −1.11 | 0/12 (0) | NA | ||||
| YF/JE279 site-specific revertant, E279 Lys | 3.55 | 12/12 (100) | 9.4 | 1.15 | ||
| 2.55 | 11/12 (92) | 10.1 | ||||
| 1.55 | 11/12 (92) | 10.2 | ||||
| 0.55 | 3/12 (25) | 10.7 | ||||
| −0.44 | 2/12 (17) | 14 |