The P84 monoclonal antibody specifically binds to CD172a, also known as SIgnal-Regulatory Protein α (SIRPα), Src Homology 2 domain-containing protein tyrosine Phosphatase (SHP) Substrate 1 (SHPS-1), or Brain Immunoglobulin-like molecule with Tyrosine-based activation motifs (BIT). CD172a is an adhesion molecule of the Ig superfamily which is expressed on neurons in the central nervous system and the retina, on macrophages, and on bone-marrow myeloid cells. Its ligand, CD47, or Integrin-Associated Protein (IAP), is expressed by a wide variety of cells. CD172a and CD47 are proposed to mediate bi-directional signaling to modify neural synaptic activity and regulate the phagocytic activities of macrophages.
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.