Table 1.
Antagonistic effect of Cop 1 on murine T cell lines/clones in a split APC assay
| T cell Clone | Inhibitor | Coincubation, cpm (% inhibition) | Split incubation, cpm (% inhibition) |
|---|---|---|---|
| SJL-MBP p82-100 | — | 6,865 | 6,906 |
| Clone 3 | Cop 1 | 151 (97) | 4,083 (41) |
| MBP p91A | 3,003 (54) | 4,569 (34) | |
| MBP p1–11 | 1,016 (85) | 6,892 (0) | |
| PLP p139–151 | 4,363 (36) | 6,702 (3) | |
| SJL-MBP p82–100 | — | 3,222 | 3,301 |
| Line 1 | Cop 1 | 156 (95) | 2,075 (37) |
| MBP p91A | 1,299 (60) | 2,217 (33) | |
| MBP p1–11 | 1,085 (66) | 3,624 (0) | |
| PLP p139–151 | 2,170 (32) | 3,317 (0) | |
| SJL-MBP p82–100 | — | 2,532 | 2,556 |
| Clone 6 | Cop 1 | 45 (98) | 1,506 (41) |
| B10PL-MBP p1–11 | — | 6,752 | 6,799 |
| Clone 2 | Cop 1 | 1,072 (84) | 6,636 (2) |
| MBP p82–100 | 3,686 (45) | 6,534 (4) | |
| B10PL-MBP p1–11 | — | 1,692 | 1,926 |
| Clone 20 | Cop 1 | 123 (92) | 2,102 (0) |
| MBP p82–100 | 906 (46) | 1,842 (4) | |
| SJL-PLP p139–151 | — | 8,534 | 8,622 |
| Clone III | Cop 1 | 3,006 (65) | 7,896 (8) |
| MBP p82–100 | 3,446 (60) | 8,049 (9) |
Irradiated spleen cells (3 × 106/ml) were incubated with 3 μM of antigenic peptide: MBP p82–100, MBP p1–11, or PLP p139–151. Inhibitor peptide: Cop 1 (6 μM), MBP p82–100, MBP p91A, MBP p1–11, or PLP p139–151 (15 μM) was either coincubated on the same APC competing for MHC binding (coincubation) or presented on different APC, which were mixed only when added to the T cells, competing on binding to the TCR (split incubation). After 3 h, cells were washed and plated in 96-well microplates with T cells (1.5 × 104/well) for 2 additional days. Results are expressed as mean cpm thymidine incorporation for triplicate cultures. SDs were less than 20% of the mean cpm. Results represent one of four independent experiments.