The 11C1 monoclonal antibody recognizes CD268 which is also known as the B cell activating factor receptor (BAFF-R). CD268 is a type III transmembrane protein of approximately 184 residues. BAFF-R is one of the receptors for B-cell activating factor (BAFF), a member of the TNF family of proteins. BAFF is a key regulator for B cell differentiation and critical in regulating survival and activation of peripheral B cell populations. Experiments in the mouse model show that interaction of BAFF with BAFF-R promotes NF-κB activity. Overexpression of BAFF results in an expanded B cell compartment and autoimmunity in mice. Mice injected with BAFF-neutralizing-Fc (BAFF-R-Fc) protein showed reduced NF-κB activation, blocking BAFF-induced B cell proliferation. Reports suggest that the BAFF-BAFF-R interaction may lead to a better understanding of autoimmune disorders.
The antibody was conjugated to BD Horizon™ BUV661 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 661-nm. BD Horizon Brilliant BUV661 can be excited by the ultraviolet laser (355 nm) and detected with a 670/25 filter and a 630 nm LP. Due to cross laser excitation of this dye, there may be significant spillover into channels detecting APC-like emissions (eg, 670/25-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 BUV661 reagents. Therefore, the use of BD CompBeads or BD CompBeads Plus to determine spillover values for these reagents is not recommended. Different BUV661 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.