Table 2.
PRAME-stimulated PBMC react with L-1236 HL cells
| Primary stimulation | Stimulatory cells in ELISPOT | Donor 1 | Donor 2 | Donor 3 | Donor 4 | Donor 5 |
|---|---|---|---|---|---|---|
| None | None | 0 | 0 | 0 | 24 | – |
| None | T2 | 26 | 31 | 27 | 34 | – |
| None | T2-SLY (PRAME) | 46 | 66 | 26 | 33 | – |
| None | L-1236 | 80 | 31 | 16 | 38 | – |
| T2 | None | 0 | 0 | – | – | 24 |
| T2 | T2 | 0 | 36 | – | – | 110 |
| T2 | T2-SLY (PRAME) | 0 | 119 | – | – | – |
| T2 | L-1236 | 0 | 22 | – | – | 137 |
| T2-SLY | None | 39 | 0 | 23 | 222 | 60 |
| T2-SLY | T2 | 288 | 344 | 278 | 290 | – |
| T2-SLY | T2-LDY (LIPI) | – | – | – | – | 150 |
| T2-SLY | T2-SLY (PRAME) | 283 | 538 | 390 | 362 | 160 |
| T2-SLY | L-1236 | 190 | 294 | 237 | 295 | 107 |
| T2-ALY | None | – | – | – | – | 46 |
| T2-ALY | T2-LDY (LIPI) | – | – | – | – | 190 |
| T2-ALY | T2-ALY (PRAME) | – | – | – | – | 248 |
| T2-ALY | L-1236 | – | – | – | – | 246 |
| T2-VLD | None | – | – | – | – | 62 |
| T2-VLD | T2-LDY (LIPI) | – | – | – | – | 222 |
| T2-VLD | T2-VLD (PRAME) | – | – | – | – | 203 |
| T2-VLD | L-1236 | – | – | – | – | 215 |
HLA-A2-positive PBMC were primed with T2 cells or with T2 cells that had been pulsed with 100 μg/ml of PRAME-derived peptides SLY, ALY and VLD, respectively (primary stimulation). Reactivity of stimulated cells with T2 cells and L-1236 cells was assessed by interferon gamma ELISPOT. For this end, T2 cells had been pulsed with PRAME-derived peptides (T2-SLY, T2-ALY and T2-VLD), peptides derived by the irrelevant antigen LIPI (T2-LDY) or left un-pulsed (T2). Presented are means from triplicates after background subtraction. – not done