Table 1.
Comparison of the GrB ELISPOT and 51Cr-release assays for measuring TALL-104 cell activity.
| Effector:Target Ratio | 51Cr-Release Assaya (% Cytotoxicity ± SE) | GrB ELISPOT Assayb (Spots/well ± SE) |
| 10:1 | 65 ± 4 | TNTCc |
| 5:1 | 57 ± 10 | TNTC |
| 2.5:1 | 47 ± 11 | TNTC |
| 1:1 | 20 ± 5 | TNTC |
| 0.5:1 | 9 ± 2 | TNTC |
| 0.2:1 | 2 ± 1 | 316 ± 50 |
| 0.1:1 | 2 ± 1 | 144 ± 13 |
| 0.05:1 | 1 ± 1 | 80 ± 6 |
| 0.02:1 | 0 ± 1 | 33 ± 4 |
a The 51Cr-release assay was performed with the effector:target cell ratio as specified for 4 h at 37°C. Data presented as average cytotoxicity ± SE (n = 3).
bThe granzyme B ELISPOT assay was performed with K562 cells at a constant number of 5 × 104 cells per well and effector:target cell ratio as specified for 4 h at 37°C. Data presented as average spots/well ± SE (n = 3).
cTNTC= Too numerous to count accurately.