The HI111 monoclonal antibody specifically binds to CD11a, the 180 kDa integrin α chain. This type I transmembrane glycoprotein associates with CD18 (integrin β2) to form the heterodimeric glycoprotein CD11a/CD18. This heterodimer is also known as the lymphocyte (leukocytes) function associated antigen-1 (LFA-1) that is expressed on all leukocytes. LFA-1 is an adhesion molecule involved in lymphocyte and granulocyte functions. LFA-1 mediates adhesion of lymphoid cells to the vascular endothelium in association with its ligand, and the intracellular adhesion molecule-1 (ICAM-1), CD54. Other ligands are ICAM-2 (CD102) and ICAM-3 (CD50).
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.