Figure 1.

HIV infection of LNCaP cells. LNCaP or HeLa-CD4 cells in 24-well culture plates (10⁴ cells/well) were infected with HIV either with or without gp120 protein on its envelope [Env(-) and Env(+) HIV]. A) A significantly high percentage of EGFP-positive cells was demonstrated in the LNCaP cell cultures infected by HIV Env(-) virus (9–14%). Infection of HeLa-CD4 cells by HIV Env(+) was used as a positive control to assess anti-gp120 or -gp160 function of the antibodies. Infection of HeLa cells was performed as a negative control. The infections of HIV either with or without Env showed very low infectivity for HeLa cells, as demonstrated with no EGFP-positive cells in the infected culture, or occasionally there were one or two EGFP-positive colonies. In other experiments, we also infected HeLa-CD4 cells with Env(-) HIV_NL4-3, and found that the Env(-) HIV strain did not infect HeLa-CD4. These results have been previously reported (22). B) Infection of CD4(-) cell lines by HIV_NL4-3-Env(-)-EGFP virus prepared from an oral epithelial cell line derived from a patient. The cell line was established and maintained in our laboratory. C) Infection of the LNCaP and HeLa-CD4 cell lines by HIV at various concentrations. Because the figure is in log scale, the standard deviations do not appear clearly. These are: 1) LNCaP: 900 ± 38 (5 ng), 205 ± 11(1.5 ng), 24 ± 5.6 (0.5 ng), 8.5 ± 0.7 (0.15 ng), 2.5 ± 0.7 (50 pg); and 2) HeLa-CD4: 1114 ± 115 (5 ng), 638 ± 47 (1.5 ng), 80 ± 10 (0.5 ng), 14.5 ± 2.1 (0.15 ng), 3.5 ± 0.71 (50 pg), 1 ± 0 (15 pg).