Table 1.
Characteristics of the 373E1 Immunoreactivity as Determined by Combined Direct and Competitive ELISA and Dot-Blotting Using Human Articular Cartilage Aggrecan as a Model Antigen
| Treatment of model antigen | Added competitor | Treatment of competitor | Relative level of immunoreactivity* |
|---|---|---|---|
| None | – | – | 3 |
| Endo-β-galactosidase | – | – | 0 |
| Keratanase I | – | – | 1/(2) |
| Keratanase II | – | – | 1 |
| Chondroitinase ABC | – | – | 3 |
| Chondroitinase ACII | – | – | 3 |
| O-glycosidase | – | – | 3 |
| β-galactosidase | – | – | 3 |
| Endoglycosidase H/F | – | – | 2/(3) |
| N-glycosidase A† | – | – | 3 |
| Neuraminidase CP | – | – | >3 |
| Neuraminidase VC | – | – | >3 |
| Neuraminidase NDV | – | – | >3 |
| N-acetylglucosaminidase | – | – | 3 |
| N-acetyl-β-d-glucosaminidase | – | – | 3 |
| Fucosidase | – | – | 3 |
| α-1,3/4-l-fucosidase | – | – | 3 |
| Chemical desulfation | – | – | 3 |
| – | Fucosyl-lactose | – | 3 |
| – | 3′-N-Ac-Neu-lac | – | 3 |
| – | 6′-N-Ac-Neu-lac | – | 3 |
| – | N-Ac-Neu-lac-N-neo-tetraose | – | 3 |
| – | N-Ac-NeuA | – | 3 |
| – | Dermatan sulfate | – | 3 |
| – | Chondroitin sulfates | – | 3 |
| – | Heparan sulfate | – | 3 |
| – | Hyaluronan | – | 3 |
| – | Keratan sulfates‡ | – | 0 |
| – | Keratan sulfates | Keratanase I | 1 |
| – | Keratan sulfates | Keratanase II | 3 |
| – | Keratan sulfates | Endo-β-galactosidase | 3 |
| – | Aggrecan§ | Papain | 1 |
| – | Aggrecan§ | Trypsin | 1 |
* Arbritary units for relative immunoreactivity are: 3, strong; 2, moderate; 1, weak; 0, no reactivity.
† Similar results were obtained with N-glycosidase A and F;
‡ Different results were obtained with keratan sulfates purified from cornea and cartilage indicating a further specificity of the 373E1 for certain keratan sulfate structures.
§ Human articular and bovine nasal cartilage aggrecans were extensively digested with the indicated enzyme and the dialysed digest was subsequently used as a competitor.
Abbreviations: CP, Clostridium perfringens; VC, Vibro cholerea; NDV, Newcastle disease virus; 3′-N-Ac-Neu-lac, 3′-N-acetylneuramin-lactose; 6′-N-Ac-Neu-lac, 6′-N-acetylneuramin-lactose; N-Ac-Neu-lac-N-neo-tetraose, N-acetylneurami-lacto-N-neo-tetraose; N-Ac-NeuA, N-acetylneuraminic acid.