The HIS51 monoclonal antibody specifically binds to the rat Thy-1 antigen (CD90) expressed by hematopoietic stem cells, early myeloid and erythroid cells, immature B lymphocytes in the bone marrow and peripheral lymphoid organs, thymocytes, recent thymic emigrants (a subset of CD45RC- peripheral T cells), neurons, glomerular mesangial cells, endothelium at inflammatory sites, mast cells, and bone marrow-derived dendritic cells. Rat dendritic epidermal T cells (DEC) are Thy-1-negative. CD90 is a GPI-anchored membrane glycoprotein of the Ig superfamily which is involved in signal transduction. In addition, there is evidence in the mouse that CD90 mediates adhesion of thymocytes to thymic stroma. HIS51 antibody cross-reacts with the mouse Thy-1.1 alloantigen of the AKR/J and PL strains, but not Thy-1.2 found on most strains. In the mouse, CD90 is found on thymocytes, most peripheral T lymphocytes, some intraepithelial T lymphocytes (IEL, DEC), hematopoietic stem cells, and neurons, but not B lymphocytes.
The antibody was conjugated to BD Horizon BUV615 which is part of the BD Horizon Brilliant™ Ultraviolet family of dyes. This dye is a tandem fluorochrome with an Ex Max near 350 nm and an Em Max near 615 nm. BD Horizon Brilliant BUV615 can be excited by the ultraviolet laser (355 nm) and detected with a 610/20 filter and a 595 nm LP. Due to the excitation of the acceptor dye by the blue/yellow-green laser line, there may be significant spillover into channels detecting PE-CF594 like emissions (eg, 610/20-nm filter).