TABLE 1.

Titer determinations of DENV and DiD-labeled DENV

PreparationVirus infectivityaNo. of GCPs/mlNo. of particles/mlIU:GCP ratioIU:particle ratio
No. of PFU/mlNo. of IU/ml
DENVb8.0 × 1071.2 × 1083.1 × 10118.6 × 10121:2,6001:72,000
Unpurified DENVND3.6 × 1068.3 × 109ND1:2,300ND
DiD-labeled DENVcND7.5 × 1061.3 × 1010ND1:1,800ND
  • a Average of at least two determinations. ND, not done.

  • b Used for preparation of DiD-labeled virus.

  • c Used for binding and tracking experiments.