Recombinant Rat VISTA/B7-H5/PD-1H Fc Chimera Protein, CF

Recombinant Rat VISTA/B7-H5/PD-1H Fc Chimera (Catalog # 2288-B7) inhibits IFN-gammasecretion by human peripheral blood mononuclear cells in the presence ofanti-CD3 antibody. The ED50 for this effect is 1-6 μg/mL.

2 μg/lane of Recombinant Rat VISTA/B7-H5/PD-1H was resolved with SDS-PAGE underreducing (R) and non-reducing (NR) conditions and visualized by Coomassie® Bluestaining, showing bands at 60-70 kDa and 120-140 kDa, respectively.

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

Recombinant Rat VISTA/B7-H5/PD-1H Fc Chimera Protein, CF Summary

• Details of Functionality: Measured by its ability to inhibit anti-CD3 antibody induced IFN-gamma secretion by human peripheral blood mononuclear cells (PBMC). The ED₅₀ for this effect is 1-6 μg/mL.
• Source: Mouse myeloma cell line, NS0-derived rat VISTA/B7-H5/PD-1H protein
  

  Rat VISTA (Met1-Ala192) Accession # NP_001037765.1	IEGRMD	Human IgG1 (Pro100-Lys330)
  N-terminus		C-terminus

• Accession #: NP_001037765.1
• N-terminal Sequence: Ile33
• Structure / Form: Disulfide-linked homodimer
• Protein/Peptide Type: Recombinant Proteins
• 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: 44.6 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: 60-70 kDa, reducing conditions

Packaging, Storage & Formulations

• Storage:
  • 12 months from date of receipt, ≤ -20 °C as supplied.
  • 1 month, 2 to 8 °C under sterile conditions after reconstitution.
  • 3 months, ≤ -20 °C under sterile conditions after reconstitution.
• Buffer: Lyophilized from a 0.2 μm filtered solution in PBS.
• Purity: >95%, by SDS-PAGE visualized with Silver Staining and quantitative densitometry by Coomassie® Blue Staining.
• Reconstitution Instructions: Reconstitute at 200 μg/mL in PBS.

Notes

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

Alternate Names for Recombinant Rat VISTA/B7-H5/PD-1H Fc Chimera Protein, CF

• 4632428N05Rik
• B7H5
• B7-H5
• C10orf54
• chromosome 10 open reading frame 54
• Dies1
• Gi24
• PD1H
• PD-1H
• platelet receptor Gi24
• PP2135
• SISP1
• stress induced secreted protein 1
• VISTA
• VSIR

Background

V-domain Ig suppressor of T cell activation (VISTA), also known as platelet receptor Gi24, Dies1, SISP1, PD-1H, and B7‑H5, is a 50-60 kDa transmembrane glycoprotein with homology to B7-like immune co-stimulatory molecules (1, 2). Mature rat VISTA contains a 160 amino acid (aa) extracellular domain (ECD) with one Ig-like domain, a 24 aa transmembrane segment, and a 96 aa cytoplasmic domain. The ECD of rat VISTA shares a 78% and 67% aa sequence identity with mouse and human VISTA, respectively. In human VISTA, a 30 kDa ECD can be shed by MT1‑MMP, leaving a 25-30 kDa fragment remaining in the membrane (3). VISTA promotes both MT1‑MMP expression and the MT1-MMP mediated activation of MMP-2 (3). VISTA has been shown to support the differentiation of embryonic stem cells (ESC) and enhances BMP-4 induced signaling in ESC, but it is also down-regulated following BMP-4 exposure (4, 5). Vista can bind directly to BMP-4, but it also associates with the type I BMP receptor Activin RIB/ALK 4 (4, 5). VISTA is highly expressed on mature CD11b high myeloid-derived APCs and to a lesser extent on CD4⁺, CD8⁺, and T regs and is also found on tumor infiltrating lymphocytes (7). It is up-regulated in vivo on activated monocytes and dendritic cells (5). VISTA inhibits CD4⁺ and CD8⁺ T cell proliferation, and their production of IL2 and IFN-gamma (6). Its expression on tumor cells attenuates the antitumor immune response and enables more rapid tumor progression (6). Suppression of VISTA signaling was shown to increase the rate of progression in the mouse autoimmune disease model EAE (6). VISTA-Ig suppressed proliferation of T cells but not B cells and blunted the production of T cell cytokines and activation markers, suggesting that VISTA as a negative checkpoint regulator suppresses T cell activation (8, 9).

1. Flajnik, M.F. et al. (2012) Immunogenetics 64:571.
2. Wilcox, R.A. et al. (2012) Eur. J. Haematol. 88:465.
3. Sakr, M.A. et al. (2010) Cancer Sci. 101:2368.
4. Aloia, L. et al. (2010) J. Biol. Chem.285:7776.
5. Parisi, S. et al. (2012) FASEB J. 26:3957.
6. Wang, L. et al. (2011) J. Exp. Med. 208:577.
7. Flies, D.B. et al. (2014) J Clin Invest. 124:1966.
8. Lines, J.L. et al. (2014) Cancer Res. 74:1924.
9. Nowak, E.C. et al. (2017) Immunol Rev. 276:66.

Bioinformatics

• Uniprot:
  • NP_001037765.1()