Table 2.

Effect of CXCR4 on infectivity of the FIV envelope glycoproteina

VirusTitration methodInfectivity (FFU/ml) on:CrFK/CrFK.CXCR4 infectivity ratio
CrFKCrFK.CXCR4
FIV 34TF10FIAb 1.19 × 104 ± 0.89 × 104 9.75 × 104 ± 0.83 × 104 8.2
Endpoint dilutionb 5.12 × 104 1.15 × 106 22.6
CT5Δpol(FIV)FIA 5.3 × 104 ± 0.4 × 103  6.5 × 104 ± 0.9 × 104 12.5
CT5Δpol(VSV-G)FIA1.95 × 104 ± 0.1 × 105 1.87 × 104 ± 0.1 × 105 0.95
  • a See Materials and Methods and Results for experimental details. CrFK versus CrFK.CXCR4 comparisons were performed simultaneously with the same viral preparation.

  • b Different FIV preparations were used for the FIA and endpoint dilution experiments with infectious FIV.