Detection of B7‑H4 in HEK293 Human Cell Line Transfected with Human B7-H4 and eGFP by Flow Cytometry. HEK293 human embryonic kidney cell line transfected with human B7-H4 and eGFP were stained with either (A) Mouse Anti-Human B7‑H4 PE‑conjugated Monoclonal Antibody (Catalog # FAB6576P) or (B) Mouse IgG2B Phycoerythrin Isotype Control (Catalog # IC0041P). View our protocol for Staining Membrane-associated Proteins.
Preparation and Storage
The product is shipped with polar packs. Upon receipt, store it immediately at the temperature recommended below.
Stability & Storage
Protect from light. Do not freeze.
12 months from date of receipt, 2 to 8 °C as supplied.
B7-H4, also known as VTCN1, B7x and B7S1, is a 50‑80 kDa glycosylated member of the BTN/MOG family of immunomodulatory protein (1, 2). Mature human B7-H4 consists of a 235 amino acid (aa) extracellular domain (ECD) with two Ig-like V-type domains, a 21 aa transmembrane segment, and a 2 aa cytoplasmic tail (3-5). Within the ECD, human B7-H4 shares 90% aa sequence identity with mouse and rat B7-H4. It shares 22%-28% aa sequence identity with human B7-1, B7-2, B7-H1, B7-H2, B7-H3, and PD‑L2. Alternate splicing of human B7-H4 generates an additional isoform that lacks the first Ig-like domain. B7-H4 is expressed on the surface of activated lymphocytes, macrophages, monocytes, dendritic cells, epithelial cells, and bone marrow-derived mesenchymal stem cells (4-8). Following binding to activated T cells, B7-H4 serves as a co‑inhibitor of the T cell response. This is accomplished by reverse signaling that can induce either cell cycle arrest, or apoptosis in B7-H4 expressing cells (2-5, 9, 10). B7‑H4 is up‑regulated in several carcinomas in correlation with tumor progression and metastasis (2, 7, 11, 12). A soluble form of B7-H4 is elevated in the serum of ovarian cancer, renal cell carcinoma, and rheumatoid arthritis patients, and is correlated with advanced disease status (13-15). Soluble B7‑H4 functions as a decoy molecule that blocks the inhibitory influence of B7‑H4 on immune activation (15). Despite evidence for the involvement of B7-H4 in immune regulation, mice deficient in its expression do not show significant immune deficiencies, suggesting compensation by other molecules in vivo (16).
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B7 Homolog 4
Entrez Gene IDs:
79679 (Human); 242122 (Mouse)
B7h.5; B7H4; B7-H4; B7H4T-cell costimulatory molecule B7x; B7S1; B7S1VCTN1; B7x; B7XPRO1291; FLJ22418; Immune costimulatory protein B7-H4; Protein B7S1; T cell costimulatory molecule B7x; V-set domain containing T cell activation inhibitor 1; V-set domain-containing T-cell activation inhibitor 1; Vtcn1