The L60 monoclonal antibody specifically binds to CD43 which is also known as Leukosialin (LSN) or Galactoglycoprotein (GALGP). CD43 is a ~95-135 kDa heavily O-sialylated type I transmembrane glycoprotein that is encoded by SPN (sialophorin) and belongs to the cell surface mucin family. The L60 antibody recognizes a sialic acid-dependent determinant on CD43. CD43 is highly expressed on T lymphocytes, thymocytes, monocytes, granulocytes, bone marrow stem cells, pre-B cells and activated B cells plasma cells but not on resting peripheral blood B cells, red blood cells, and non-hematopoietic cells. CD43 is enzymatically shed from leucocyte surfaces following activation by various stimuli. CD43 appears to be involved in mediating intercellular interactions that regulate leucocyte functions.
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.