Recombinant Human VEGF-Ax Protein, CF

• Reactivity: Hu
• Applications: Bioactivity
• Format: Carrier-Free

Recombinant Human VEGF-Ax Protein, CF Summary

• Additional Information: VEGF 165 Extended Isoform
• Details of Functionality: Measured by its binding ability in a functional ELISA. When Recombinant Human VEGF R2/KDR/Flk‑1 Fc Chimera (Catalog # 357-KD) is immobilized at 0.5 µg/mL (100 µL/well), the concentration of Recombinant Human VEGF-Ax that produces 50% of the optimal binding response is approximately 1-6 ng/mL.
  Recombinant Human VEGF-Ax weakly binds to Recombinant Human Neuropilin‑1 (Catalog # 3870-N1).
• Source: Chinese Hamster Ovary cell line, CHO-derived human VEGF protein
  

  Human VEGF-A (Ala27-Arg191) Accession # NP_001303939	SAGQEEGASLRVSGTRSLTRKD
  N-terminus	C-terminus

• Accession #: NP_001303939
• N-terminal Sequence: Ala27
• Structure / Form: Disulfide-linked homodimer
• Protein/Peptide Type: Recombinant Proteins
• Gene: VEGFA
• Purity: >95%, by SDS-PAGE visualized with Silver Staining and quantitative densitometry by Coomassie® Blue Staining.
• Endotoxin Note: <0.10 EU per 1 μg of the protein by the LAL method.

Applications/Dilutions

• Dilutions:
  • Bioactivity
• Theoretical MW: 21 kDa .
  Disclaimer note: The observed molecular weight of the protein may vary from the listed predicted molecular weight due to post translational modifications, post translation cleavages, relative charges, and other experimental factors.
• SDS-PAGE: 22-29 kDa, reducing conditions

Packaging, Storage & Formulations

• Storage: Use a manual defrost freezer and avoid repeated freeze-thaw cycles.
  • 12 months from date of receipt, -20 to -70 °C as supplied.
  • 1 month, 2 to 8 °C under sterile conditions after reconstitution.
  • 3 months, -20 to -70 °C under sterile conditions after reconstitution.
• Buffer: Lyophilized from a 0.2 μm filtered solution in HCl.
• Purity: >95%, by SDS-PAGE visualized with Silver Staining and quantitative densitometry by Coomassie® Blue Staining.
• Reconstitution Instructions: Reconstitute at 250 μg/mL in 4 mM HCl.

Notes

This product is produced by and ships from R&D Systems, Inc., a Bio-Techne brand.

Alternate Names for Recombinant Human VEGF-Ax Protein, CF

• MVCD1
• VAS
• vascular endothelial growth factor A
• Vascular permeability factor
• Vasculotropin
• VEGF
• VEGFA
• VEGF-A
• VEGFMGC70609
• VPF
• VPFvascular endothelial growth factor

Background

Vascular endothelial growth factor (VEGF or VEGF-A), also known as vascular permeability factor (VPF), is a potent mediator of both angiogenesis and vasculogenesis in the fetus and adult (1, 2). It is a member of the PDGF family that is characterized by the presence of eight conserved cysteine residues and a cystine knot structure (3). Humans express two sets of alternatively spliced isoforms of 121, 145, 165, 183, 189, and 206 amino acids (aa) in length (3, 4). Isoforms other than VEGF₁₂₁ contain basic heparin-binding regions and are not freely diffusible (3, 4). VEGF₁₆₅ appears to be the most abundant and potent of the angiogenic isoform set, followed by VEGF₁₂₁ and VEGF₁₈₉ (3, 5). The anti-angiogenic or “b” set of isoforms is differentially spliced to contain six alternative amino acids at the C-terminus, and are the more highly expressed isoforms in normal adult tissue (6). VEGF_165b, like VEGF₁₂₁ but unlike most angiogenic isoforms, does not bind heparins and is therefore diffusible (3). Human VEGF₁₆₅ shares 88% aa sequence identity with corresponding regions of mouse and rat, 96% with porcine, 95% with canine, and 93% with feline, equine and bovine VEGF₁₆₅, respectively. In addition to alternatively spliced VEGF isoforms, multiple fragments of VEGF can be generated by extracellular proteolysis (4). VEGFs bind the type I transmembrane receptor tyrosine kinases VEGF R1 (also called Flt-1) and VEGF R2 (Flk-1/KDR) on endothelial cells (3). Although VEGF affinity is highest for binding to VEGF R1, VEGF R2 appears to be the primary mediator of VEGF angiogenic activity (3, 5). VEGF₁₆₅ binds the semaphorin receptor, Neuropilin-1 and promotes complex formation with VEGF R2 (7). An extended form of VEGF-A, known as VEGF-Ax, results from the C-terminal addition of 22 amino acids (8). VEGF-Ax is produced by vascular endothelial cells, retains the ability to bind VEGF R2 but not Neuropilin-1, and functions as an anti-angiogenic protein (8). VEGF is required during embryogenesis to regulate the proliferation, migration, and survival of endothelial cells (3, 5). In adults, VEGF functions mainly in wound healing and the female reproductive cycle (5). Pathologically, it is involved in tumor development and tumor vascular leakage (9). Circulating VEGF levels correlate with disease activity in autoimmune diseases such as rheumatoid arthritis, multiple sclerosis, and systemic lupus erythematosus (10). VEGF is induced by hypoxia and cytokines such as IL-1, IL-6, IL-8, Oncostatin M, and TNF-alpha (5, 11).

1. Leung, D.W. et al. (1989) Science 246:1306.
2. Keck, P.J. et al. (1989) Science 246:1309. 
3. Robinson, C.J. and S.E. Stringer (2001) J. Cell. Sci. 114:853.
4. Vempati, P. et al. (2014) Cytokine Growth Factor Rev. 25:1.
5. Byrne, A.M. et al. (2005) J. Cell. Mol. Med. 9:777. 
6. Nowak, D.G. et al. (2008) J. Cell Sci. 121:3487.
7. Pan, Q. et al. (2007) J. Biol. Chem. 282:24049.
8. Eswarappa, S.M. et al. (2014) Cell 157:1605.
9. Goel, H.L. and A.M. Mercurio (2013) Nat. Rev. Cancer 13:871.
10. Carvalho, J.F. et al. (2007) J. Clin. Immunol. 27:246.
11. Angelo, L.S. and R. Kurzrock (2007) Clin. Cancer Res. 13:2825.

FAQs for VEGF (9018-VE/CF). (Showing 1 - 1 of 1 FAQ).

1. Why is the molecular weight of VEGF different from the similar antibody, for some companies the the molecular weight is 40KD)?
   • I can't comment on another company's antibody because I don't have any information about their products. I can tell you that VEGF is expressed in a variety of isoforms and is subject to various post-translational modifications that influence its apparent molecular weight in an SDS-PAGE gel compared to the theoretical molecular weight.

Bioinformatics

• Gene Symbol: VEGFA
• Uniprot:
  • NP_001303939()