Fig. 4

Susceptibility of CD4+ T cells from young and elderly individuals to HIV-1 infection and replication. a Replication kinetics of NL4-3 X4 or R5 GFP reporter virus constructs in PBMCs. Infections were carried out after stimulation with CD3/CD28 beads using virus stocks containing 1 ng p24 antigen. Shown are mean values (±SEM) of six infections of PBMC cultures from young (blue) or elderly (red) donors. b Cumulative levels of RT production at days 5, 7, and 10 post-infection for each infected PBMC culture. c Average numbers of HIV-1-infected GFP+ cells detected in PBMC cultures at days 3, 5, and 7 post-infection. d Levels of HIV-1 RT activity in the cell culture supernatants (cumulative 5, 7, 10 dpi) divided by the average numbers of virally infected (GFP+) cells (values from 3, 5, 7 dpi). e Correlation between the age of the PBMC donors and the normalized quantity of HIV-1 production. Each symbol represents the result obtained for one individual PBMC donor