Table 1.
Structure−activity relationship of peptide inhibitors against the PD1/PDL1 interaction in comparison to pembrolizumab.
| ID | S (mM)a | Tm (°C) | %-Foldb | ELISAc EC50 (μM) |
|---|---|---|---|---|
| 1a | 5.4 ± 0.2 | n.a. | 0% | 9.69 ± 0.10 |
| 1b | 17.8 ± 0.3 | n.a. | RC | no binding |
| 1c | 0.3 ± 0.1 | n.a. | 0% | 3.70 ± 1.02 |
| 1d | 3.4 ± 0.1 | 59 | 91 ± 1% | 7.05 ± 0.35 |
| 1e | 0.9 ± 0.1 | 37 | 55 ± 1% | 0.29 ± 0.11 |
| 2a | 5.8 ± 0.2 | 52 | 87 ± 1% | 3.50 ± 0.12 |
| 2b | 0.6 ± 0.1 | 47 | 81 ± 1% | 7.08 ± 0.27 |
| 2c | 8.2 ± 0.2 | 25 | 54 ± 1% | 0.58 ± 0.18 |
| Pem | − | − | − | 0.9 10−3 ± 0.2 |
a
Thermodynamic solubility measured in a phosphate buffer (PB, 50 mM) at pH 7.4 (mean ± s.d., N = 3).
b
Hairpin folded fractions calculated at 293K from the best-fitted melting curves of thermal denaturation recorded by CD spectroscopy.
c
EC50 values obtained from the inhibitory dose-response curves of the PD1/PDL1 interaction at 293K. Data are reported as the average of triplicates (N = 3) with the corresponding s.d.