FIG. 7.

Plasma antigenemia, CD4 percentage, PBMC load, and RNA copy (equivalents per milliliter) measurements for animals infected with SHIVnef recombinants containing 1486D Nef sequences. (A) Plasma antigenemia in SHIVnef-infected rhesus monkeys. p27 concentrations in plasma were determined at the time points indicated. The limit of detection is approximately 0.05 ng/ml. The week 0 sample is a preinfection sample taken immediately before inoculation with SHIVnef. (B) CD4 percentages in SHIVnef-infected rhesus monkeys. Whole blood was drawn from SHIVnef-inoculated animals at various times postinoculation and stained with OKT4, a fluorescein isothiocyanate-conjugated murine monoclonal antibody that was raised against rhesus macaque CD4 (American Type Culture Collection). The stained samples were analyzed using a FACSscan flow cytometer (Becton Dickinson). (C) Frequencies of infectious cells in PBMC of SHIVnef-infected rhesus macaques. Viral loads were graded on a scale from 0 to 10 indicating the number of PBMC needed to recover SIV. A value of 0 denotes that no virus was recovered using 10⁶ cells, 1 denotes successful virus recovery from 10⁶ cells, and 2 to 10 denote successful virus recovery from 333,333, 111,111, 37,037, 12,345, 4,115, 1,371, 457, 152, or 51 cells, respectively. (D) Plasma SIV RNA levels at the indicated weeks postinoculation for animals infected with SHIVnef recombinants. The dashed line indicates the threshold sensitivity of the assay, 300 copy eq/ml. A value of 0 was assumed for week 0.