Assay Range | 156 - 10,000 pg/mL |
Sensitivity | 10.0 pg/mL |
Size | 96T |
Storage | Store at 2 - 8ºC. Keep reconstituted standard and detection Ab at -20 ºC |
Assay Principle | Sandwich ELISA |
Sample volume | 100 µL final volume, dilution factor varies on samples. |
Detection Method | Chromogenic |
Kit Components
1. Recombinant Human TSP2 standard: 2 vials
2. One 96-well plate precoated with anti-Human TSP2 Ab
3. Sample diluent buffer: 12 mL - 1
4. Detection antibody: 130 µL, dilution 1:100
5. Streptavidin-HRP: 130 µL, dilution 1:100
6. Antibody diluent buffer: 12 mL x1
7. Streptavidin-HRP diluent buffer: 12 mL x1
8. TMB developing agent: 10 mL x1
9. Stop solution: 10 mL x1.
10. Washing solution (20x): 25 mL x1.
Background
Thrombospondin-2, also known as TSP-2 and THBS-2, is a member of the Thrombospondin family which includes Thrombospondin-1 and -2 constituting subgroup A and form disulfide-linked homotrimers, as well as Thrombospondin-3, -4, and -5/COMP (cartilage oligomeric matrix protein) compromising subgroup B and form homopentamers. The human Thrombospondin-2 is synthesized as a 1172 amino acid (aa) precursor that includes an 18 aa signal peptide, an N-terminal heparin-binding domain, an oligomerization motif, one vWF-C (von Willebrand factor type C) domain, three Thrombospondin type-1 repeats, three EGF-like repeats, seven Thrombospondin type-3 repeats, and a lectin-like Thrombospondin C-terminal globular domain. Human Thrombospondin-2 shares 88-90% aa sequence identity with bovine, mouse, and rat Thrombospondin-2.
Primarily, Thrombospondin-2 has been shown to counteract blood vessel growth. The three Thrombospondin type-1 domains inhibit VEGF-induced EC migration and vascular tube formation. In vivo, full length Thrombospondin-2 can block tumor angiogenesis and induce vascular EC apoptosis. Histidine-proline-rich glycoprotein (HPRG) prevents interaction of Thrombospondin-2 with another putative receptor, CD36, on macrophages and vascular EC. The activities of Thrombospondin-2 are regulated by a number of putative receptors. The heparin-binding domain of Thrombospondin-2 mediates interactions with several integrins including α3β1 and α6β1 on microvascular endothelial cells (EC), and integrin α4β1 on large blood vessel EC. Thrombospondin-2 may also interact directly with integrins via an RGD (Arg-Gly-Asp) sequence in the type-3 repeat region, or indirectly through C-terminal-binding to integrin-associated protein (IAP/CD47). A fragment from heparin-binding domain to vWF-C domain in Thrombospondin-2 promotes EC survival, proliferation, and chemotaxis. In the heart, Thrombospondin-2 may play a role in maintaining myocardial matrix integrity, and in the nervous system, it has been shown to promote synaptogenesis.