The V46-1954 monoclonal antibody specifically recognizes mouse CD304, also known as neuropilin 1 (Nrp1). It does not cross-react with neuropilin 2 (Nrp2). CD304 is a type-1 transmembrane protein that plays important roles in neuronal development, angiogenesis, and immunosuppression. Through interactions with plexins and VEGF receptors on neurons and endothelial cells, it is a co-receptor for the class III semaphorin subfamily and vascular endothelial growth factor (VEGF), respectively. The ability of the S1 protein of SARS-CoV-2 virus to bind to Nrp1, a potential mechanism for cellular infection, is being investigated. In the immune system, CD304 is expressed on natural (thymus-derived) Treg cells and may be responsible for the unsuccessful immune regulation of tumor growth.
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).