• Purity

  >90%, by SDS-PAGE under reducing conditions and visualized by silver stain

• Endotoxin Level

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

• Activity

  Measured by its ability to inhibit anti-CD3 antibody induced IL-2 secretion in human T lymphocytes. The ED    ₅₀ for this effect is typically 2-10 μg/mL.

• Source

  Human embryonic kidney cell, HEK293-derived

  Human B7-H7/HHLA2 (Ile23-Asn344) Accession # Q9UM44	IEGRMD	Human IgG1 (Pro100-Lys330)
  N-terminus		C-terminus

• Accession #

• N-terminal Sequence    
  Analysis

  Ile23

• Structure / Form

  Disulfide-linked homodimer

• Predicted Molecular Mass

  64 kDa (monomer)

• SDS-PAGE

  90-100 kDa, reducing conditions

Background: B7-H7/HHLA2

B7-H7, also known as HHLA2 (HERV-H LTR-associating 2), is a member of the B7 family of immune regulatory proteins (1, 2). Mature human B7-H7 consists of a 322 amino acid (aa) extracellular domain (ECD) with three immunoglobulin-like domains, a 21 aa transmembrane segment, and a 49 aa cytoplasmic domain (3-5). B7‑H7 is constitutively expressed on monocytes and is up-regulated by LPS and IFN-gamma stimulation. It is expressed on LPS/IFN-gamma treated B cells but not on resting B cells (5). B7-H7 binds to cell surface determinants on resting and mature T cells, B cells, and monocytes as well as on immature and mature dendritic cells (5). Soluble B7-H7 inhibits the proliferation of activated CD4  ⁺ and CD8  ⁺ T cells and their production of IFN-gamma, TNF-alpha, IL-5, IL-10, IL-13, IL-17A, and IL-22 (5).

• References:

1. Zou, W. and L. Chen (2008) Nat. Rev. Immunol. 8:467.

2. Bour-Jordan, H. et al. (2011) Immunol. Rev. 241:180.

3. Mager, D.L. et al. (1999) Genomics 59:255.

4. Flajnik, M.M. et al. (2012) Immunogenetics 64:571.

5. Zhao, R. et al. (2013) Proc. Natl. Acad. Sci. USA 110:9879.

• Long Name:

  B7 Homolog 7

• Entrez Gene IDs:

  11148 (Human)

• Alternate Names:

  B7H7; B7-H7; HERV-H LTR-associating 2; HERV-H LTR-associating protein 2; HHLA2; Human endogenous retrovirus-H long terminal repeat-associating protein 2