Figure 2

Comparison of proliferation index (PI) in three donors (A, B, and C) human PBLs cultured with either PHA or particles surface-engineered with CD80, CD86, and antiCD3-sFv (B7+antiCD3). In Panel A, surface-engineered HSV-based particles are derived from HSV-2 infected genetically surface-modified Lof(11-10) cells (horizontal hatched bars). In Panel B, surface-engineered HIV-based particles are derived from genetically surface-modified 1119 cells that are chronically-expressing human immunodeficiency virus type-1 (gray-filled bars). The time course shown is 4, 6, 8, and 12 days for PHA-treated cultures; 4, 6, 8, 12, and 18 days for surface-engineered particle treated cultures. Proliferation Index establishes a proliferation ratio between exposed cultures and non-exposed cultures. PHA treated cultures are not exposed to particles. For PHA (black-filled bars), the proliferation value in the presence of PHA (i.e. Donor-A, 6 hour timepoint = 10,900 relative fluorescent units) is divided by untreated cultures not exposed to PHA (i.e. Donor-A, 6 hour timepoint = 2,500 relative fluorescent units); for B7+antiCD3, the proliferation value in the presence of B7+antiCD3 surface-engineered particles (i.e. Donor-A, 6 hour timepoint = 26,700 relative fluorescent units for HSV-2 in panel A; 11,000 relative fluorescent units for HIV-1 in panel B) is divided by the proliferation value observed with non-engineered viral-based particles (i.e. Donor-A, 6 hour timepoint = 2,300 relative fluorescent units for HSV-2 in panel A; 2,300 relative fluorescent units for HIV-1 in panel B). The remaining PI values are calculated in a similar fashion. Almost identical "background" values are observed for non-PHA exposed and non-engineered particles in Donors-A, -B, and -C cultures. Actual induced values can be calculated by multiplying the PI value by the "background" value. Particle preparations used in this figure were PEG-concentrated (200× for HIV; 25× for HSV) and inactivated to render them non-infectious.