Active Recombinant Human ICOSLG protein, Fc/Avi-tagged, Biotinylated

• Cat.No.: ICOSLG-051H
• Product Overview: Biotinylated Recombinant Human ICOSLG(Ala19-Thr139) protein, fused to Fc/Avi tag at the C-terminus, was expressed in HEK293 cells .

Specification

• Description: B7-H2, also known as B7-related protein (B7RP1), ICOS Ligand, and CD275, is an approximately 60 kDa transmembrane glycoprotein in the B7 family of immune regulatory molecules (1). Mature human B7-H2 consists of a 238 amino acid (aa) extracellular domain (ECD) with two immunoglobulin-like (Ig-like) domains, a 21 aa transmembrane segment, and a 25 aa cytoplasmic domain (2, 3). Within the ECD, human B7-H2 shares 50% and 54% aa sequence identity with mouse and rat B7‑H2, respectively. Alternative splicing generates a long isoform (Isoform 2), which carries a 10 aa substitution for the C-terminal 3 residues, and a short isoform (Isoform 3; this product), which lacks the first Ig-like domain (aa 18 - 134 is missing). B7-H2 is expressed on antigen presenting cells such as B cells, macrophages, monocytes, and dendritic cells (2-6). It binds to ICOS on activated T cells, leading to both positive and negative effects on immune responses including its own down-regulation (2, 4, 7). Mouse and human B7-H2 exhibit cross-species binding to ICOS (3, 6). The B7-H2 interaction with ICOS is costimulatory for T cell proliferation as well as the development of B cells, plasma cells, follicular helper T cells (TFH) and germinal centers (2-4, 8, 9). In human but not in mouse, B7-H2 additionally binds to CD28 and CTLA4, and its interaction with CD28 can costimulate both human and mouse naïve T cells and regulatory T cells (Treg) (6). B7-H2 contributes to the development of allergic asthma by enhancing Th2 biased immune responses, limiting Th17 responses, and promoting eosinophilic infiltration into the lung (8, 10, 11). Its activation of ICOS on Treg limits pulmonary inflammation and airway hyperresponsiveness, promotes the development of inhalational tolerance, and impairs anti-tumor immunity (5, 12, 13). In contrast, its ligation of ICOS on TFH cells can increase the severity of autoimmune symptoms (9). A soluble form of human B7-H2 is elevated in the circulation of patients with active systemic lupus erythematosus (14). In the thyroid, B7-H2 is up-regulated on thyrocytes during inflammation and promotes their proliferation and production of thryoid hormones (15).
• Source: HEK293 cells
• Species: Human
• Tag: Fc/Avi
• Predicted N Terminal: Ala19
• Form: Lyophilized from a 0.2 μm filtered solution in PBS with Trehalose.
• Bio-activity: Measured by its binding ability in a functional ELISA. When Recombinant Human ICOS Fc Chimera is immobilized at 10 μg/mL, 100 μL/well, the concentration of Biotinylated Recombinant ICOSLG Fc Chimera Avi-tag that produces 50% of the optimal binding response is approximately 10-50 μg/mL.
• Molecular Mass: 61-70 kDa, under reducing conditions
• Protein length: Ala19-Thr139
• Endotoxin: <1.0 EU per 1 μg of the protein by the LAL method.
• Purity: >95%, by SDS-PAGE visualized with Silver Staining and quantitative densitometry by Coomassie® Blue Staining.
• Applications: Bioactivity
• 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: Reconstitute at 400 μg/mL in PBS.

Gene Information

• Gene Name: ICOSLG inducible T-cell co-stimulator ligand [ Homo sapiens ]
• Official Symbol: ICOSLG
• Synonyms: ICOSLG; inducible T-cell co-stimulator ligand; ICOSL; ICOS ligand; B7 homolog 2; B7 homologue 2; B7 H2; B7 related protein 1; B7H2; B7RP 1; B7RP1; CD275; GL50; ICOS L; KIAA0653; B7-like protein Gl50; B7-related protein 1; transmembrane protein B7-H2 ICOS ligand; B7-H2; LICOS; B7RP-1; ICOS-L
• Gene ID: 23308
• mRNA Refseq: NM_015259
• Protein Refseq: NP_056074
• MIM: 605717
• UniProt ID: O75144