Description
Native human integrin aVß3 heterodimer, affinity-purified from human source tissue. Cat. 357 supplies the receptor in its functional, cation-dependent conformation — when reconstituted in Tris-HCl buffer with millimolar Mg²? and Mn²? the heterodimer is competent to bind its full panel of physiological RGD ligands (vitronectin, fibronectin, fibrinogen, osteopontin, thrombospondin, bone sialoprotein, MMP-2, LAP-TGFß, tenascin) and to recognise small-molecule RGD mimetics including cilengitide-class drug candidates.
aVß3 is the **drug-targeted "vitronectin receptor"**: it sits at the centre of tumour-driven angiogenesis (sprouting of aVß3 endothelial cells), osteoclast-mediated bone resorption (the original anti-resorptive drug-discovery target), vascular smooth-muscle migration, platelet-vessel-wall interactions and wound-healing re-epithelialisation. Because of this, cat. 357 sees most of its use in **assays where a defined, soluble, isolated RGD-receptor is required** — distinguishing aVß3-specific signal from the messier cell-based readouts that combine multiple integrins.
This is the aV-family member in YO Proteins' integrin range; the companion aVß5 (cat. 476) and a5ß1 (cat. 638) products allow direct integrin-selectivity panels for ligand and inhibitor discovery.
Specifications
Catalog number: 357
Amount: 10 µg
Source: Human (affinity-purified native heterodimer)
Composition: aV (CD51) / ß3 (CD61) heterodimer
Format: Protein solution, ready for direct use
Cation-dependence: Activity requires divalent cations (typical assay buffer: 50 mM Tris-HCl pH 7.4, 150 mM NaCl, 2 mM MgCl2, 1 mM MnCl2)
Key ligands: Vitronectin, fibronectin, fibrinogen, osteopontin, thrombospondin, bone sialoprotein, MMP-2, LAP-TGFß, tenascin; cyclo-RGD peptides (cilengitide / RGDfV-class)
Applications
- **Quartz crystal microbalance (QCM) / surface plasmon resonance (SPR) binding studies** — typical working concentration ~20 µg/mL of integrin in Tris/NaCl/Mg²?/Mn²? buffer flowed over RGD-functionalised gold sensor surfaces for label-free real-time affinity, kinetics and on/off-rate measurement.
- **Drug-discovery screening of aVß3 antagonists** — in-vitro receptor-binding assays for cilengitide-class cyclic RGD peptides, small-molecule RGD mimetics and antibody-based vitronectin-receptor inhibitors. Cat. 357 paired with cat. 476 (aVß5) gives a clean aVß3-vs-aVß5 selectivity panel; adding cat. 638 (a5ß1) extends to the RGD-integrin trio for full integrin-cross-reactivity profiling.
- **Receptor immobilisation in solid-phase binding assays (ELISA-format)** — coat plates with cat. 357, block, then quantify binding of biotinylated RGD ligands, RGD-presenting peptides, anti-integrin antibodies or candidate inhibitors.
- **Characterisation of photo-, redox- or pH-activatable RGD ligands** — defined-receptor binding readouts for caged-RGD, photoswitchable-RGD and stimuli-responsive RGD-presenting surfaces and hydrogels.
- **Reference receptor for vitronectin / fibronectin / fibrinogen binding studies** — when the experimental question is "does this ligand engage aVß3 specifically?" rather than "does it bind a cell?"
- **Antigen for raising anti-aVß3 (anti-CD51 / anti-CD61) antibodies** and for epitope-mapping monoclonals against the aVß3 heterodimer.
- **Reagent for angiogenesis, osteoclast biology and wound-healing in-vitro models** where a defined RGD-receptor input is required (sprouting endothelial-cell assays, bone-resorption pit assays, scratch / migration assays with aVß3-engaged surfaces).
CITED USE CASES
Wirkner M., Weis S., San Miguel V., Álvarez M., Gropeanu R.A., Salierno M., Sartoris A., Unger R.E., Kirkpatrick C.J., del Campo A. (2011) — Photoactivatable caged cyclic RGD peptide for triggering integrin binding and cell adhesion to surfaces. ChemBioChem 12(17): 2623–2629. doi:10.1002/cbic.201100437.
The authors used the YO Proteins human integrin aVß3 (cat. 357) as the receptor input in quartz-crystal-microbalance (QCM) binding studies of a photoactivatable caged cyclic RGD peptide — cyclo[RGD(DMNPB)fK] — designed to phototrigger cell adhesion on otherwise cell-repellent surfaces. Integrin solutions were prepared at ~20 µg/mL in 50 mM Tris-HCl pH 7.4 / 150 mM NaCl / 2 mM MgCl2 / 1 mM MnCl2 — the cation-supplemented buffer required to maintain the active aVß3 conformation — and flowed over RGD-functionalised gold QCM crystals at 50 µL/min for 4 min 30 s, followed by a 35-min static binding window and a buffer rinse. With cat. 357 as the defined receptor input, the study demonstrated that (i) the caged cyclo[RGD(DMNPB)fK] does *not* engage aVß3, (ii) UV-photolysis of the DMNPB cage at the aspartate COOH (a coordinating ligand of the aVß3 metal-ion-dependent adhesion site) cleanly restores aVß3 binding, and (iii) the same molecular switch translates to spatiotemporally controlled cell attachment, patterning and gradient generation on cell-repellent PEGylated surfaces. The work established a quantitative, integrin-defined photoswitching platform for tissue-engineering and cell-pattern applications and validates cat. 357 as a benchmark aVß3 receptor for QCM-based RGD-ligand characterisation.
