Fusion protein mapping of anti-vIL-6 mAbs.
Schematic representation of deletion mutants of vIL-6 fusion proteins. Numbers above each box represent the amino acid positions relative to the start methionine. Restriction enzyme sites AatII andEcoRI used to construct M3 and M5, respectively, are indicated. The reactivity of each mAb to each fusion protein was determined by ELISA. The reactivity of each mAb to each fusion protein is shown as positive (+) when the absorbance (A405/550) was significantly higher (0.7 absorbance units) than the background or negative (−) when the absorbance was similar (within 0.05 absorbance units) to the background. The black box represents the putative vIL-6 signal peptide portion.5 The dotted box denotes a 13-amino acid peptide of vIL-6 that is recognized by 4 neutralizing mAbs against vIL-6. The bold characters indicate the second conserved cysteine residues. vIL-6 sites I, II, and III are defined based on the crystal structure of the vIL-6/gp130 complex.22
