Source

Human B7-H2, mouse Fc Tag is expressed from human 293 cells (HEK293). It contains AA Asp 19 - Ser 258 (Accession # O75144-1).

Molecular Characterization

This protein carries a mouse IgG1 Fc tag at the C-terminus.

Endotoxin

Less than 0.01 EU/mg by the LAL method.

Purity

>95% as determined by SDS-PAGE.

Formulation

Lyophilized from 0.22 μm filtered solution in 50 mM Tris, 100 mM Glycine, 25 mM Arginine, 150 mM NaCl, pH7.5. Normally trehalose is added as protectant before lyophilization.

Reconstitution

Please see Certificate of Analysis for specific instructions.

For best performance, we strongly recommend you to follow the reconstitution protocol provided in the CoA.

Storage

For long term storage, the product should be stored at lyophilized state at -20°C or lower.

Please avoid repeated freeze-thaw cycles.

No activity loss was observed after storage at:

4-8°C for 12 months in lyophilized state;

-70°C for 3 months under sterile conditions after reconstitution.

Background

ICOS ligand (ICOSLG) is also known as B7 homolog 2 (B7-H2), B7-related protein 1 (B7RP-1) and CD antigen CD275, which belongs to the immunoglobulin superfamily and BTN/MOG family. ICOSLG contains one Ig-like C2-type (immunoglobulin-like) domain and one Ig-like V-type (immunoglobulin-like) domain. Isoform 1 is widely expressed, while isoform 2 is detected only in lymph nodes, leukocytes and spleen. B7-H2 is ligand for the T-cell-specific cell surface receptor ICOS. B7-H2 acts as a costimulatory signal for T-cell proliferation and cytokine secretion and induces also B-cell proliferation and differentiation into plasma cells. B7-H2 could play an important role in mediating local tissue responses to inflammatory conditions, as well as in modulating the secondary immune response by co-stimulating memory T-cell function.

Reference

(1) Aicher A., et al., 2000, J. Immunol. 164:4689-4696.

(2) Yoshinaga SK., et al., Int Immunol 12 (10): 1439–47.