Bonemarrow Stromal Antigen 2/CD317

Bone marrow stromal Antigen-2 (BST-2) is a 30- to 36-kDa type II transmembrane protein, consisting of 180 amino acids. It has been shown to form a complex with Rho-GTPase activating protein, RICH2 (1). This complex is essential for the organization of subapical actin cytoskeleton. BST-2 protein is expressed on certain bonemarrow stromal cell lines and on various normal tissues.  The expression pattern of BST2 is relatively different form another bone marrow stromal antigen 1 (BST1).  The BST-2 gene is located on chromosome 19p13.2.  BST-2 surface expression on fibroblast cell lines facilitated the stromal cell-dependent growth of a murine bone marrow-derived pre-B-cell line, DW34.  Some studies suggest that BST-2 may be involved in pre-B-cell growth development by regulating their surface molecules and cytokines (2).  BST2 is also expressed in synovial cell lines from where the BST2 gene was cloned.  BST2 is predominantly expressed in liver, lungs, heart, placenta and lower levels in pancreas, kidney, skeletal muscle and brain.  Naturally all human cells possess an antiviral activity that inhibits the release of retrovirus particles, and other enveloped virus particles.  This antiviral activity is antagonized by the HIV-1 accessory protein, Vpu.  The antiviral activity can be constitutively induced and expressed by interferon-alfa and is consist of protein based “tetherins” that cause retention of fully formed virions on infected cell surface. BST2 (CD317) was identified as tetherin whose expression correlated with and induced, a requirement for Vpu during HIV-1 and murine leukaemia virus particle release.  Vpu and BST2 are co localized in the same cell compartments.  Further depletion of BST2 in cells that require Vpu induction for HIV-1 virion release, abolish VPU role in particle release (3).  Manipulation of  Vpu function and consequent mobilization of tetherin’s antiviral activity could be a potential therapeutic strategy in HIV/AIDS infection. Interferon alfa also enhances BST2 expression and antitumor activity of anti-BST2 antibody in renal cell carcinoma xenograft models (4). 

The Bone marrow stromal Antigen 2-selective antibodies were generated against peptides form unique regions on the extra cytoplasmic portion of the protein.  FabGennix Inc. has generated specific rabbit anti-BST2 polyclonal antibodies utilizing linear and cyclic peptide sequences.  These antibodies have been fully characterized for cross reactivity with other members of the bone marrow stromal cell antigen 1 and other proteins.    FabGennix Inc. has produced antibodies to multiple epitopes on the same protein that will facilitate studies utilizing interspecies cross reactivity.

FabGennix Inc. provides BST2 Western blot positive control in “ready-to-use” SDS-PAGE sample buffer.  The BST2 positive control appears as a diffuse band of 30-36 kDa.   FabGennix International Inc. also has several diagnostics related antibodies to various targets, for a complete listing please visit www.FabGennix.com.  Limited quantities of antigenic blocking peptides for these antibodies are also available, inquire before placing the orders.    

For research use only, not for diagnostic or therapeutic use.