FIG. 2.

PBMC from HIV type 1 (HIV-1)-infected survivors of PML (HIV+/PML S # 1 to 4) have cytolytic activity specific for the JCV T and VP1 proteins. T- and VP1-specific effector cells could be detected in three of four and four of four HIV-positive PML survivors, respectively. PBMC from one recently diagnosed HIV-negative PML patient who showed clinical improvement had cytolytic activity against the VP1 protein. PBMC were stimulated with autologous, fixed B-LCL expressing the T or VP1 protein in interleukin-2-containing medium and assessed for effector function using autologous target cells infected with recombinant vaccinia virus-T, -VP1, or the wild-type vaccinia virus. The percent specific lysis indicates the difference in specific ⁵¹Cr release between cells infected with the T- or VP1-expressing vaccinia virus and those infected with the wild-type vaccinia virus. E:T ratios are shown in the box in the upper left panel.