The V7.1 monoclonal antibody specifically recognizes CD101 which is also known as P126 or Glu-Trp-Ile EWI motif-containing protein 101 (EWI-101). CD101 is encoded by IGSF2 (Immunoglobulin superfamily member 2) and belongs to the EWI (sharing a conserved glutamine-tryptophan-isoleucine motif) family within the Ig superfamily. CD101 is a ~135-140 kDa type I transmembrane glycoprotein that has a short cytoplasmic domain with potential phosphorylation sites and an extracellular region with seven immunoglobulin-variable (IgV)-like domains. CD101 is expressed as homodimers by granulocytes, monocytes, dendritic cells, and some T cells. Its expression by T cells may be upregulated upon activation through the CD3 complex. CD101 may play a role in TCR/CD3-dependent T-cell activation.
The antibody was conjugated to BD Horizon™ BUV496 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 496-nm. BD Horizon BUV496 can be excited by the ultraviolet laser (355 nm) and detected with a 515/30 nm filter with a 450LP. Due to the excitation of the acceptor dye by other laser lines, there may be significant spillover into the channel detecting BD Horizon V500 or BV510 (eg, 525/40-nm filter). However, the spillover can be corrected through compensation as with any other dye combination.