The 2B11/CXCR4 monoclonal antibody specifically binds to mouse CD184, which is also known as the C-X-C Chemokine Receptor type 4 , CXCR4. CXCR4 (previously known as Fusin and LESTR), is a seven-transmembrane, G-protein-coupled receptor. It is the specific receptor for the CXC chemokine, SDF-1/CXCL12. Mouse CXCR4 shows 91% homology at the amino acid level with human CXCR4. CXCR4 is widely expressed by hematopoietic and non-hematopoietic cell types including neutrophils, monocytes, T cells, B cells, CD34-positive progenitor cells, endothelial cells, neurons and astrocytes. Human CXCR4 is used by T-tropic HIV-1 as a co-receptor for viral entry. The mouse Cxcr4 gene has been mapped to chromosome 1.
The antibody was conjugated to BD Horizon™ BUV737 which is part of the BD Horizon Brilliant™ Ultraviolet family of dyes. This dye is a tandem fluorochrome of BD Horizon BUV395 with an Ex Max of 348-nm and an acceptor dye with an Em Max at 737-nm. BD Horizon Brilliant BUV737 can be excited by the ultraviolet laser (355 nm) and detected with a 740/35 filter. Due to the excitation of the acceptor dye by other laser lines, there may be significant spillover into channels detecting Alexa Fluor® 700-like dyes (eg, 712/20-nm filter).
Due to spectral differences between labeled cells and beads, using BD™ CompBeads can result in incorrect spillover values when used with BD Horizon BUV737 reagents. Therefore, the use of BD CompBeads or BD CompBeads Plus to determine spillover values for these reagents is not recommended. Different BUV737 reagents (eg, CD4 vs. CD45) can have slightly different fluorescence spillover therefore, it may also be necessary to use clone specific compensation controls when using these reagents.