The YTH 76.3rMAb is a recombinant monoclonal antibody that specifically recognizes a monomorphic epitope on the extracellular region of the Human Leukocyte Antigen-B (HLA-B) heavy chain. This major histocompatibility complex (MHC) class I antigen is comprised of a polymorphic HLA-B heavy chain, a ~45 kDa type I transmembrane glycoprotein encoded by HLA-B, that is noncovalently associated with the invariant ~12 kDa Beta-2 (β2)-microglobulin light chain encoded by B2M. Hundreds of HLA-B alleles have been reported. HLA-B is expressed on most nucleated cells and leucocytes including specialized antigen presenting cells such as thymic epithelial cells and dendritic cells. HLA-B plays a major role in the MHC-restricted presentation of small peptides, including those derived from self or foreign antigens, that can be bound by TCR expressed on CD8+ thymocytes or T cells leading to either immune tolerance, the maturation of naïve CD8+ T cells, or the activation and differentiation of CD8+ cytotoxic effector T cells or memory CD8+ T cells. HLA-B also functions as a ligand for regulatory CD8 coreceptor molecules and some CD158 molecules that serve as regulatory MHC class I antigen receptors expressed by CD8+ T cells and NK cells. The YTH 76.3rMAb is derived from the hybridoma clone YTH 76.3, with Rat IgG2a, κ isotype. YTH 76.3rMAb has variable region sequences from the original YTH 76.3 clone appended to Rat IgG1 and kappa constant region sequences.
The antibody was conjugated to BD Horizon BB700, which is part of the BD Horizon Brilliant™ Blue family of dyes. It is a polymer-based tandem dye developed exclusively by BD Biosciences. With an excitation max of 485 nm and an emission max of 693 nm, BD Horizon BB700 can be excited by the 488 nm laser and detected in a standard PerCP-Cy™5.5 set (eg, 695/40-nm filter). This dye provides a much brighter alternative to PerCP-Cy5.5 with less cross laser excitation off the 405 nm and 355 nm lasers.