FIG. 4.

Vpu-specific expression of IFN-γ in subject 26 is mediated by autologous serum. (A) Ficoll-separated PBMCs or fresh blood washed twice to remove plasma from subject 26 was incubated with either fetal calf serum or autologous serum comprising 5% of the culture together with the Vpu peptide epitope in an ICS assay. (B) Whole blood from subject 26 was washed to remove plasma and incubated with autologous serum comprising 50%, 5%, or 0.5% of the culture together with the Vpu peptide epitope. (C) Autologous PBMCs and plasma from subject 26 were mixed with PBMCs or plasma from an HIV-negative donor.