FIG 2.

Single- and multiple-cycle growth kinetics of recombinant FCV and their inactivation by soluble GST-fJAM-A. CRFK monolayers were infected with viruses at an MOI of 5 (A) or 0.01 (B), and change in virus titer was determined by plaque assay. The mean log₁₀ titer (log₁₀ titer at each time point minus log₁₀ titer at time zero) from three replicates is shown. Error bars represent the standard deviations from three independent experiments. Statistically significant differences in titer between recombinant FCV-Urbana and FCV-5–Urbana chimera as determined by two-way ANOVA are indicated by asterisks. For virus inactivation, 1 × 10⁵ PFU of each virus was incubated with or without soluble GST-fJAM-A (27.5 mM) at 37°C (C) or 4°C (D) for 30 min. The remaining infectivity of each sample was assayed by plaque titration. The change in log titer was calculated by subtracting the titer of samples incubated with receptor from that of samples incubated with GST alone. The mean change in log₁₀ titer ± SD from three replicates of a representative experiment is shown. *, P < 0.05; **, P < 0.01; ***, P < 0.001.