The UP-H1 monoclonal antibody recognizes Immune receptor expressed by myeloid cells 2 (IREM-2) which is also known as CD300 antigen like family member E (CD300e), CMRF35-like molecule 2 (CLM2), or Polymeric immunoglobulin receptor 2 (PIgR2). IREM-2 is a 34 kDa type I transmembrane glycoprotein which belongs to the CMFRF35 subfamily of the immunoglobulin (Ig) superfamily. IREM-2 is expressed on monocytes, macrophages and myeloid dendritic cells (mDCs), but not on lymphoid dendritic cells or granulocytes. IREM-2 associates with DAP-12, an ITAM-containing adapter molecule, which provides activating signals. Crosslinking of IREM-2 leads to intracellular calcium mobilization, release of proinflammatory cytokines such as TNF, and increased expression of activation markers on monocytes and mDCs. IREM-2 activation of mDCs can reportedly enhance the alloreactive response of naive T cells.
The antibody was conjugated to BD Horizon™ BV421 which is part of the BD Horizon Brilliant™ Violet family of dyes. With an Ex Max of 407-nm and Em Max at 421-nm, BD Horizon BV421 can be excited by the violet laser and detected in the standard Pacific Blue™ filter set (eg, 450/50-nm filter). BD Horizon BV421 conjugates are very bright, often exhibiting a 10 fold improvement in brightness compared to Pacific Blue conjugates.