Recombinant Human B7-1/CD80 Fc Chimera Protein, CF

Recombinant Human B7‑1/CD80 Fc Chimera (Catalog #10133-B1) induces IL-2 secretion by Jurkat human acute T cell leukemia cells in thepresence of PHA. The ED50 for this effect is 0.025-0.15 μg/mL.

2 μg/lane of Recombinant Human B7‑1/CD80Fc Chimera (Catalog # 10133-B1) was resolved with SDS-PAGE under reducing (R) and non-reducing (NR)conditions and visualized by Coomassie® Blue staining, showing bands at 66-80 kDaand 130-160 kDa, respectively.

Avi-tag Biotinylated Recombinant Human CTLA-4 Fc protein (AVI7268) was immobilized on a Biacore Sensor Chip CM5 via the Avi-tag biotin, and binding to Recombinant Human B7-1/CD80 Fc protein (Catalog # 10133-B1) was measured at a concentration range between 82 pM and 21 nM. The double-referenced sensorgram was fit to a 1:1 binding model to determine the binding kinetics and affinity, with an affinity constant of KD=0.2511 nM.

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

Recombinant Human B7-1/CD80 Fc Chimera Protein, CF Summary

• Details of Functionality: Measured by its ability to induce IL-2 secretion by Jurkat human acute T cell leukemia cells. Freeman, G.J. et al. (1993) Science 262:909. The ED₅₀ for this effect is 0.025‑0.15 µg/mL in the presence of PHA.
• Source: Chinese Hamster Ovary cell line, CHO-derived human B7-1/CD80 protein
  

  Human B7-1/CD80 (Val35-Asn242) Accession # P33681	IEGRMD	Human IgG1 (Pro100-Lys330)
  N-terminus		C-terminus

• Accession #: P33681
• N-terminal Sequence: Val35
• Structure / Form: Disulfide-linked homodimer
• Protein/Peptide Type: Recombinant Proteins
• Purity: >95%, by SDS-PAGE under reducing conditions and visualized by silver stain.
• Endotoxin Note: <0.10 EU per 1 μg of the protein by the LAL method.

Applications/Dilutions

• Dilutions:
  • Bioactivity
• Theoretical MW: 50.5 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: 66-80 kDa, under 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 PBS with Trehalose.
• Purity: >95%, by SDS-PAGE under reducing conditions and visualized by silver stain.
• Reconstitution Instructions: Reconstitute at 500 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 Human B7-1/CD80 Fc Chimera Protein, CF

• Activation B7-1 antigen
• B7
• B71
• B7-1
• BB1
• CD28LG1
• CD28LGB7-1 antigen)
• CD80 antigen
• CD80 molecule
• CD80
• costimulatory factor CD80
• costimulatory molecule variant IgV-CD80
• CTLA-4 counter-receptor B7.1
• T-lymphocyte activation antigen CD80

Background

B7-1/CD80 and B7-2/CD86, together with their receptors CD28 and CTLA-4, constitute one of the dominant co-stimulatory pathways that regulate T- and B-cell responses (1). Although both CTLA-4 and CD28 can bind to the same ligands, CTLA-4 binds to B7-1 and B7-2 with a 20-100 fold higher affinity than CD28 and is involved in the down-regulation of the immune response (2-6). Mature human B7-1 consists of a 208 amino acid (aa) extracellular domain (ECD) with two immunoglobulin-like domains, a 21 aa transmembrane domain, and a 25 aa cytoplasmic domain (7). Within the ECD, human B7-1 shares 50% aa sequence identity with mouse B7-1. Alternative splicing generates a 30 kDa soluble isoform that lacks the transmembrane segment and retains the ability to bind CD28 and CTLA-4 and an isoform that lacks the second Ig-like domain and the transmembrane segment (8). Both human and mouse B7-1 and B7-2 can bind to either human or mouse CD28 and CTLA-4 (1). B7-1 is expressed on activated B cells, activated T cells, and macrophages. B7-2 is constitutively expressed on interdigitating dendritic cells, Langerhans cells, peripheral blood dendritic cells, memory B cells, and germinal center B cells (2).

1. Ville, S. et al. (2015) Front. Immunol. 6:411.
2. Azuma, M. et al. (1993) Nature 366:76.
3. Freeman, G.J. et al. (1993) Science 262:909.
4. Chen, C. et al. (1994) J. Immunol. 152:4929.
5. Freeman, G.J. et al. (1993) J. Exp. Med. 178:2185
6. Lanier, L. et al. (1995) J. Immunol. 154:97.
7. Freeman, G.J. et al. (1989) J. Immunol. 143:2714.
8. Kakoulidou, M. et al. (2007) Scand. J. Immunol. 66:529.

Bioinformatics

• Uniprot:
  • P33681()