Table 1.
Effect of multiple costimulatory modalities to enhance CTL avidity
| Vaccine Modality | Precursor Frequency/105 CD8 T-cells | Tetramer dissociation time (Min) | Peptide concentration for CTL (nM) | ||
|---|---|---|---|---|---|
| Buffer (HBSS) | 800 | ND | NA | ||
| β-gal peptide/IFA | 1500 | 50 | 720 | ||
| rV-LacZ | 2650 | 1X | 85 | 160 | 1X |
| rV-LacZ/B7-1 | 3800 | 1.4X | 127 | 27 | 6X |
| rV-LacZ/TRICOM | 5900 | 2.2X | 300 | 3 | 53.3X |
| rV-LacZ + Isotype control mAb | 2424 | 1X | 70 | ND | |
| rV-LacZ + CTLA-4 mAb | 4191 | 1.7X | 90 | ND | |
| rV-LacZ/B7-1 + Isotype control mAb | 3393 | 1.4X | 118 | ND | |
| rV-LacZ/TRICOM + Isotype control mAb | 5709 | 2.4X | 235 | ND | |
| rV-LacZ/TRICOM + CTLA-4 mAb | 8536 | 3.5X | 310 | ND | |
| rV-LacZ/TRICOM + GM-CSF | 8200 | 1.4X | 360 | 0.05 | 3,200X |
| rV-LacZ/TRICOM + GM-CSF + CTLA-4 mAb | 13500 | 5.1X | 475 | 0.003 | 53,333X |
| Buffer (HBSS) | 133 | ND | NA | ||
| rV-CEA | 321 | 1X | 88 | 510 | 1X |
| rV-CEA/B7-1 | 584 | 1.8X | 135 | 110 | 4.6X |
| rV-CEA/TRICOM | 769 | 2.4X | 233 | 5 | 102X |
| rV-CEA | 455 | 1X | 70 | 950 | 1X |
| rV-CEA + CTLA-4 mAb | 784 | 1.7X | 105 | 237 | 4X |
| rV-CEA/B7-1 | 674 | 1.5X | 120 | 135 | 7X |
| rV-CEA/TRICOM + CTLA-4 mAb | 1303 | 4X | 370 | 0.4 | 1,275X |
| rV-CEA/TRICOM + GM-CSF | 1289 | 4X | 315 | 0.6 | 850X |
| rV-CEA/TRICOM + GM-CSF + CTLA-4 mAb | 1690 | 5.3X | 480 | 0.02 | 25,500X |