Recombinant Viral B18R Fc Chimera Biotinylated Protein, CF

Catalog #: BT8185
1 Citation Datasheet / COA / SDS

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BT8185-025

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Summary Product Datasheets Carrier Free Data Images Reconstitution Calculator Background Related Research Areas

Recombinant Viral B18R Fc Chimera Biotinylated Protein, CF Summary

Product Specifications

Purity

>90%, by SDS-PAGE visualized with Silver Staining and quantitative densitometry by Coomassie® Blue Staining.

Endotoxin Level

<0.10 EU per 1 μg of the protein by the LAL method.

Activity

Measured by its ability to inhibit Type-I IFN-mediated anti-viral activity. Symons, J.A. et al. (1995) Cell 81:551. The ED₅₀ for this effect, as measured by inhibition of Recombinant Human IFN‑ alpha 2 (Catalog # 11105-1) , is 0.3-1.8 ng/mL.

Source

Human embryonic kidney cell, HEK293-derived viral B18R protein

MD	Human IgG₁ (Pro100-Lys300)	IEGR	Viral B18R (His20-Glu351) Accession # P25213
N-terminus			C-terminus

Accession #

P25213

N-terminal Sequence
Analysis

Met

Structure / Form

Disulfide-linked homodimer, biotinylated via sugars

Predicted Molecular Mass

65 kDa (unlabeled)

Product Datasheets

BT8185

Product Datasheet

COA

SDS

Carrier Free

What does CF mean?

CF stands for Carrier Free (CF). We typically add Bovine Serum Albumin (BSA) as a carrier protein to our recombinant proteins. Adding a carrier protein enhances protein stability, increases shelf-life, and allows the recombinant protein to be stored at a more dilute concentration. The carrier free version does not contain BSA.

What formulation is right for me?

In general, we advise purchasing the recombinant protein with BSA for use in cell or tissue culture, or as an ELISA standard. In contrast, the carrier free protein is recommended for applications, in which the presence of BSA could interfere.

BT8185

Formulation	Lyophilized from a 0.2 μm filtered solution in PBS.
Reconstitution	Reconstitute at 250 μg/mL in PBS.
Shipping	The product is shipped with polar packs. Upon receipt, store it immediately at the temperature recommended below.
Stability & 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.

Reconstitution Calculator

Background: B18R

B18R (Soluble interferon alpha/beta receptor B18) is a 60-65 kDa protein encoded by the Vaccinia virus genome and by the genomes of other orthopoxviruses. Its function represents one of several mechanisms used by these viruses to evade the host immune response (1, 2). It is known as B18R in the Western Reserve (WR) strain of Vaccinia but as B19R in the Copenhagen strain (3). There is a structurally-unrelated, larger Vaccinia protein that is also known as B18R (or B16R) that contains multiple ankyrin-like repeats (4). The soluble interferon receptor B18R, however, contains three immunoglobulin-like domains and shows homology to human, mouse, and bovine type I interferon receptors (5). The Wyeth strain of Vaccinia virus encodes a truncated protein that lacks the C-terminal Ig-like domain, and B18R is functionally absent in the Lister strain (6, 7). B18R functions as a decoy receptor for type I interferons (IFN alpha, beta, omega). It binds to type I interferons from multiple species and prevents IFN signaling through its receptors (6-8). B18R binds to the surface of virus infected and uninfected cells where it retains its capacity to bind and neutralize IFN (6, 8). It shields those cells from the antiviral effects of type I interferons, thereby enabling virus replication and pathogenicity (6-8). B18R also limits the effectiveness of IFN alpha produced following TLR activation (9), and it limits adaptive T cell responses (3).

References

Smith, G.L. et al. (2013) J. Gen. Virol. 94:2367.
Perdiguero, B. and M. Esteban (2009) J. Interferon Cytokine Res. 29:581.
Gomez, C.E. et al. (2012) J. Virol. 86:5026.
Goebel, S.J. et al. (1990) Virology 179:247.
Smith, G.L. and Y.S. Chan (1991) J. Gen. Virol. 72:511.
Alcami, A. et al. (2000) J. Virol. 74:11230.
Symons, J.A. et al. (1995) Cell 81:551.
Colamonici, O.R. et al. (1995) J. Biol. Chem. 270:15974.
Waibler, Z. et al. (2009) J. Virol. 83:1563.

Long Name

Soluble Interferon alpha/beta Receptor B18

Entrez Gene IDs

3707577 (Viral)

Alternate Names

B18R

Related Research Areas

Citation for Recombinant Viral B18R Fc Chimera Biotinylated Protein, CF

R&D Systems personnel manually curate a database that contains references using R&D Systems products. The data collected includes not only links to publications in PubMed, but also provides information about sample types, species, and experimental conditions.

1 Citation: Showing 1 - 1