A soluble binding assay for measuring 3H-FK506 binding to the hsp56 immunophilin
| Autor: | Karen L. Leach, V. A. Ruff, A. W. Yem, M. R. Deibel |
|---|---|
| Rok vydání: | 1994 |
| Předmět: |
T cell
Immunology Blotting Western Polyenes Jurkat cells Chromatography Affinity Tacrolimus Tacrolimus Binding Proteins Radioligand Assay Affinity chromatography Heat shock protein medicine Tumor Cells Cultured Humans Heat-Shock Proteins FK506 binding Pharmacology Sirolimus Chemistry Ligand binding assay Binding protein DNA-Binding Proteins medicine.anatomical_structure Biochemistry Carrier Proteins Quantitative analysis (chemistry) Protein Binding |
| Zdroj: | Journal of immunoassay. 15(4) |
| ISSN: | 0197-1522 |
| Popis: | Heat shock protein 56 (hsp56) was previously identified as an immunophilin based on its ability to specifically bind to FK506-AffiGel 10. In this report, we have quantitated human Jurkat T cell hsp56 binding to 3H-FK506, as well as to the immunosuppressant rapamycin. Binding was measured utilizing immunoadsorbed hsp56, and, in addition, we demonstrate that 3H-FK506 binds to hsp56 in solution. Hsp56 bound to an antibody-Sepharose column binds 3H-FK506 with an affinity of 19.4 ± 4.6 nM, as compared to 23.2 ± 6.8 nM for soluble hsp56. In competition experiments, the apparent affinity constant for rapamycin was 11.6 ± 2.8 nM, using immobilized hsp56, and 17.3 ± 7.7 nM, using the soluble hsp56 preparation. These results demonstrate that hsp56 binds FK506 and rapamycin with similar affinities, and suggest that hsp56 may play a role in mediating the cellular function of both of these drugs. |
| Databáze: | OpenAIRE |
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