FIG. 6.

Kinetics of antibody production in response to inoculation with the rearranged and wt viruses. Groups of six mice were inoculated intranasally with serial 10-fold dilutions of N1G4 (wt), G1N2, G3N4, or G1N4 ranging from 10,000 to 1 PFU/animal. Control mice received inoculation medium only. The vertical dotted line indicates the day of challenge with 5.4 × 10⁶ PFU of wt virus per mouse. Serum was collected by tail bleeds from two to four animals at weekly intervals, the serum samples were pooled, and the level of antibody raised against VSV was determined by titration on detergent-lysed VSV-infected cell antigen in an ELISA. Antibody levels are expressed as log₁₀ titers. ⧫, 10,000 PFU; ●, 1,000 PFU; ▴, 100 PFU; ■, 10 PFU; ∗, 1 PFU.