The HMα2 antibody reacts with integrin α2 chain (CD49b), the 150-kDa transmembrane glycoprotein that non-covalently associates with the integrin β1 subunit (CD29) to form the integrin α2β1 complex known as VLA-2. VLA-2, a receptor for collagen and laminin, is expressed on some splenic CD4+ T lymphocytes and NK-T cells, intestinal intraepithelial and lamina propria lymphocytes, splenic NK cells, epithelial cells, and platelets; but it is not on thymocytes or Peyer's-patch or lymphnode lymphocytes. The expression of VLA-2 is upregulated on lymphocytes in response to mitogens. The HMα2 antibody has been reported to partially block the interaction of T-cell blasts, but not NK cells, with collagen. Purified HMα2 mAb blocks the staining of splenic NK cells by the anti-CD49b/Pan-NK Cells mAb DX5 (Cat. No. 553858, for the PE conjugate). Therefore, mAb HMα2 may be used like the DX5 mAb for identification of NK cells.
The antibody was conjugated to BD Horizon Red 718, which has been developed exclusively for BD Biosciences as a better alternative to Alexa Fluor® 700. BD Horizon Red 718 can be excited by the red laser (628 – 640 nm) and, with an Em Max around 718 nm, it can be detected using a 730/45 nm filter. Due to similar excitation and emission properties, we do not recommend using R718 in combination with APC-R700 or Alexa Fluor® 700.