The BMA-12 monoclonal antibody specifically binds to CD100 which is also known as, Semaphorin-4D (Sema4D), or Collapsin-4 (Coll-4). CD100 is a ~150 kDa type I transmembrane glycoprotein that belongs to the class IV Semaphorin subfamily within the Ig gene superfamily. CD100 is expressed by cells from a broad range of tissues including the nervous system, where it serves in axon guidance and synapse formation, and the kidney. It is expressed by most hematopoietic cells including T cells which express CD100 more abundantly than B cells and dendritic cell subsets. Its expression is significantly upregulated upon activation of these cell types. CD100 can costimulate T cell responses. For B cells and dendritic cells, CD100 interaction with its ligands, CD72 or Plexin B1, induces cellular activation and promotes survival, respectively. CD100 is also known to interact with Plexin B2 on skin gamma delta T cells and contribute to the repair of tissue damage caused by inflammation. A biologically-active, soluble form of CD100 is generated by proteolytic cleavage of the cell surface form.
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.