The RMT2-26 monoclonal antibody specifically recognizes T cell immunoglobulin and mucin domain-2 (TIM-2) which is also known as T-cell membrane protein 2, TIMD-2, or Tim2. TIM-2 is an ~55 kDa type I transmembrane glycoprotein that is encoded by Timd2 (T cell immunoglobulin and mucin domain containing 2) which belongs to the immunoglobulin gene superfamily. TIM-2 contains extracellular IgV and mucin domains and a cytoplasmic region with a conserved tyrosine phosphorylation motif which is involved in transmembrane signaling. A human ortholog for mouse TIM-2 has not been identified. TIM-2 is reportedly expressed on B cells with higher levels on activated B cells and germinal center B cells, type-2 T helper (Th2) cells, oligodendrocytes, and epithelial cells in the kidney and liver. It may serve as a receptor for Semaphorin 4A (Sema4A) or the heavy chain of ferritin (H-ferritin). The RMT2-26 antibody can reportedly block the binding of H-ferritin to TIM-2.
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).
Due to spectral differences between labeled cells and beads, using BD™ CompBeads can result in incorrect spillover values when used with BD Horizon BUV661 reagents. Therefore, the use of BD CompBeads or BD CompBeads Plus to determine spillover values for these reagents is not recommended. Different BUV661 reagents (eg, CD4 vs. CD45) can have slightly different fluorescence spillover therefore, it may also be necessary to use clone-specific compensation controls when using these reagents.