TABLE 3.
Reproducibility of ELISPOT assaysa
| Comparison | Assay date (mo/day/yr) | Frequency (%) of IFN-γ-producing cells |
|---|---|---|
| Assays performed on different days | 10/14/97 | 1/20 (5) |
| 3/10/98 | 1/15 (7) | |
| 10/27/97 | 1/25 (4) | |
| 12/2/97 | 1/25 (4) | |
| 11/27/97 | 1/30 (3) | |
| 1/6/98 | 1/40 (2.5) | |
| 10/27/97 | 1/25 (4) | |
| 3/24/98 | 1/25 (4) | |
| 4/21/98 | 1/16 (4) | |
| 4/8/98 | 1/6 (17) | |
| 5/12/98 | 1/7 (15) | |
| Assays performed on the same day | 1/21/98 | 1/6 (17) |
| 1/21/98 | 1/6 (17) | |
| 12/29/97 | 1/21 (5) | |
| 12/29/97 | 1/36 (3) | |
| 4/15/98 | 1/10 (10) | |
| 4/15/98 | 1/9 (11) | |
| 1/28/98 | 1/20 (5) | |
| 1/28/98 | 1/18 (6) | |
| 4/1/98 | 1/10 (10) | |
| 4/1/98 | 1/12 (8) |
a
ELISPOT assays were performed with PBMC obtained from normal donors. Cells were stimulated with PMA (1 ng/ml) plus ionomycin (1 μM) for 48 h. Assays were performed on the same or different days with PBMC of the same donors. Assays performed on the same day were set up on different plates in parallel. Spot counts in triplicate wells containing the same numbers of cells were not significantly different (P > 0.05). The mean of the difference ± SD for all paired values was 1% ± 1%.