FIG. 1.

Replication of HIV-1 isolates derived from CSF and plasma in MDM. Monocytes isolated from PBMC were plated at 1.5 × 10⁵ cells per cm² and allowed to differentiate into macrophages. After 7 days, cultures were inoculated overnight with cell-free HIV-1 inoculum (70 ng of p24 antigen per 10⁶ cells). Cultures were then washed, and the supernatant was collected periodically and assayed for p24 antigen. Collected supernatant was stored at −80°C and later applied to NT2.N-astrocyte cultures for analysis of neuronal apoptosis induction. The CSF isolates are tybe (X4), jago (R5), and doge (R5); 89.6 (R5/X4) is a PBMC isolate.