Table 2.
Adenosine receptor structure–activity analysis of IL-8 reporter stimulation in CHO cells
| HA-tag expressiona | IL-8 promoter stimulationb | |
|---|---|---|
| Mock | 0.004 ± 0.002 | 0.95 ± 0.03 |
| A2B | 0.021 ± 0.007 | 1.97 ± 0.16 |
| A2B-ΔC-tail | 0.029 ± 0.011 (p > 0.05)c | 1.56 ± 0.12 (p < 0.05) |
| Chimera 1 | 0.032 ± 0.004 (p > 0.05) | 1.08 ± 0.03 (p < 0.01) |
| Chimera 2 | 0.024 ± 0.002 (p > 0.05) | 1.08 ± 0.04 (p < 0.01) |
| Chimera 3 | 0.018 ± 0.003 (p > 0.05) | 1.74 ± 0.14 (p > 0.05) |
| Chimera 4 | 0.036 ± 0.007 (p > 0.05) | 1.94 ± 0.08 (p > 0.05) |
Cells were co-transfected with reporters and vectors encoding full-length (A2B), truncated (A2B-ΔC-tail), or chimeric A2A/A2B (depicted in Fig. 6 as chimeras 1, 2, 3, and 4) receptors, or with empty pHM6 vector (mock). Cell surface HA-tag expression (ΔOD450) and NECA-dependent stimulation of IL-8 promoter (fold) were determined as described under “Methods”
aData are results from three experiments presented as mean ± SEM
bData are results from six experiments presented as mean ± SEM
cp values in parentheses are results of one-way analysis of variance with Dunnett's post-tests versus full-length A2B receptor