Table 3.

Summary of competitive RT-PCR data

DV2 strainaNo. of copies of RNA/cellb
Positive strandNegative strand
HepG2 cells
 16681657 ± 30331 ± 17
 C0477875 ± 17525 ± 11
 K0049735 ± 3859 ± 5
 N9622875 ± 5259 ± 6
 N10421,666 ± 12512 ± 4
 N10431,500 (ND)16 (ND)
 N10471,500 (ND)16 (ND)
 N10641,583 ± 11726 ± 18
HFF cells
 1668181 ± 3716 ± 11
 C047778 ± 550.5 ± 0.4
 K0049110 ± 900.2 ± 0.5
 N9622 166 (ND)0.02
 N104244 ± 10ND
 N1043 23 (ND)<0.01c
 N1047131 ± 910.01 ± 0.02
 N1064103 ± 630.01 ± 0.01
  • a Cells (4 × 105) were exposed to Thai strains (16681, C0477, and K0049) or Nicaraguan strains (N9622, N1042, N1043, N1047, and N1064), incubated for 72 h, and harvested.

  • b Total RNA was isolated and subjected to asymmetric, competitive RT-PCR using an antisense primer for reverse transcription to measure the positive strand and a sense primer to measure the negative strand. The data are averages ± standard errors of the means. ND, not determined.

  • c The limit of sensitivity of the assay is 0.01 under these conditions.