Table 1.
Equilibrium binding parameters of low- and high-density pHLA-A2/NiNLPs interacting with live 68A62 cells at 4°C
| NiNLP1) | pMHC2) | Kapp, nM3)4°C | Enhancement factor4) | Normalized binding plateau5) |
|---|---|---|---|---|
| 5% NiNTA | cognate | 4.61±1.96 | NA | 1 |
| 5% NiNTA | non-cognate | 9.43±1.81 | NA | 0.340±0.069 |
| 5% NiNTA | cognate, mut | 31.2±7.32 | NA | 0.463±0.005 |
| 25% NiNTA | cognate | 0.829±0.368 | 5.6 | 1 |
| 25% NiNTA | non-cognate | 0.286±0.116 | 33 | 0.390±0.085 |
| 25% NiNTA | cognate, mut | 5.60±0.509 | 5.6 | 0.415±0.010 |
1)
5% and 25% NiNTA containing NLPs displayed 10 and 30 pMHC molecules per nanoparticle, respectively
2)
pMHCs were: IV9-HLA-A2 (cognate), Tax-HLA-A2 (non-cognate), IV9-HLA-A2mut (cognate with mutation in HLA-A2 diminishing interactions with CD8)
3)
Kapp, apparent equilibrium binding constants, mean±SD are based on 3 independent experiments (N=3)
4)
the ratio between Kapp measured for low- and high-density pHLA-A2/NiNLPs
5)
Binding plateau values were measured from the fit of experimental data and normalized relatively the plateau value for the cognate conjugates