The VIM15 monoclonal antibody specifically binds to CD92 which is also known as Solute carrier family 44 member 1 (SLC44A1), or Choline transporter-like protein 1 (CHTL1). CD92 is a multipass membrane glycoprotein that belongs to the choline transporter-like family. It contains a tyrosine-based inhibitory motif (ITIM) in its cytoplasmic C-terminus. CD92 appears to be involved in choline transport for cell membrane phospholipid synthesis and in regulatory cell-signaling pathways. CD92 is strongly expressed by monocytes and at lower levels by granulocytes and some dendritic cells. It is generally expressed at low levels by B cells, endothelial cells, epithelial cells, and subsets of T cells, or NK cells. The VIM15 antibody has been shown to augment lipopolysaccharide-induced IL-10 production by monocyte-derived dendritic cells (Mo-DC). When cultured with ionomycin or calcium ionophore, maturing Mo-DC showed downregulation of CD92 expression.
The antibody was conjugated to BD Horizon™ BUV563 which is part of the BD Horizon Brilliant™ Ultraviolet family of dyes. This dye is a tandem fluorochrome of BD Horizon BUV395 which has an Ex Max of 348 nm and an acceptor dye. The tandem has an Em Max at 563 nm. BD Horizon BUV563 can be excited by the 355 nm ultraviolet laser. On instruments with a 561 nm Yellow-Green laser, the recommended bandpass filter is 585/15 nm with a 535 nm long pass to minimize laser light leakage. When BD Horizon BUV563 is used with an instrument that does not have a 561 nm laser, a 560/40 nm filter with a 535 nm long pass may be more optimal. Due to the excitation and emission characteristics of the acceptor dye, there may be spillover into the PE and PE-CF594 detectors. However, the spillover can be corrected through compensation as with any other dye combination.