FIG. 1.

Effect of lymphocytes on CMV gene expression in astrocytes. CD4⁺ and CD8⁺ T cells were isolated from PBMC obtained from CMV-seropositive as well as seronegative donors and stimulated in vitro with CMV antigen. CD4⁺ (A) and CD8⁺ (B) lymphocytes were cocultured with astrocytes at the indicated ratios for 72 h prior to infection with the recombinant CMV strain RC256. Cultures were collected 72 h postinfection and assayed for β-galactosidase activity. Data, expressed as the percentages of viral expression compared to those in untreated infected controls (means ± standard errors), were obtained from five independent experiments with lymphocytes from seropositive and seronegative donors using astrocytes from different brain specimens.