Affinity for circular pUC18 dsDNA does not correlate with affinity for dsDNA oligonucleotides, but with antibody binding to Crithidia luciliae DNA
| Serum IgG | CLIFT titre | Solid phase ligands | |||||||
|---|---|---|---|---|---|---|---|---|---|
| SPADE titres* | ssDNA oligo | dsDNA oligo | pUC18 | ||||||
| pUC18 | H dsDNA | ka/kd† | Kd (SD) | ka/kd† | Kd (SD) | ka/kd† | Kd (SD) | ||
| *Relative titres of anti-dsDNA antibodies determined by solution phase anti-DNA ELISA; †see “Materials and methods” for calculations; ‡see “Materials and methods” for methodological details and calculations. No binding (NB) is here defined as complete lack of mass increase (as response units (RU)) when loading an antibody to a Biacore chip conjugated with a DNA molecule (see fig 3D for a typical example). That is, the affinity of such antibodies was below a minimum measurable threshold for DNA at the highest antibody concentration tested; §not calculated. | |||||||||
| 68 | <10 | <20 | 200 | 1.2×109 | 2.4 (4.3)×10−9 | 3.0×108 | 5.3 (4.7)×10−8 | NB‡ | NB |
| 75 | <10 | <20 | 173 | 1.5×109 | 1.8 (0.7)×10−9 | 4.2×109 | 2 (2.3)×10−9 | NB | NB |
| 135 | <10 | <20 | 221 | 1.9×109 | 2.7 (1.7)×10−9 | 1.3×109 | 3.1 (2.3)×10−9 | NB | NB |
| 144 | 160 | 105 | 318 | 4.1×108 | 4.6 (3.8)×10−9 | 8.6×108 | 1.7 (2.8)×10−8 | 3.0×107 | 1.4 (1.1)×10−8 |
| 148 | 80 | 40 | 247 | 10.0×108 | 5.6 (4.2)×10−9 | 4.8×108 | 4.8 (2.7)×10−9 | 4.0×107 | § |
| 160 | 640 | ND | ND | 1.6×109 | 2.4 (1.9)×10−9 | 1.1×108 | 2.2 (1.1)×10−8 | 1.8×109 | 2.8 (2.5)×10−9 |