The 433H monoclonal antibody specifically binds to C-C chemokine receptor type 8 (CC-CKR-8 or CCR8) which is also known as CD198, GPRCY6, CY6, CKRL1, CMKBR8, CMKBRL2, or TER1. CCR8 (CD198) is a seven-transmembrane, G-protein-coupled, glycoprotein receptor that belongs to the beta chemokine receptor family. CCR8 is expressed on monocytes, macrophages, eosinophils, Langerhans cells, thymocytes, and vascular smooth muscle cells. It is preferentially expressed on some T cell subsets including skin resident memory T cells, type 2 T-helper (Th2-like) cells, and T regulatory cells. CCR8 is a receptor for the chemokine C-C motif chemokine 1 (CCL1), also known as SCYA1 or I-309, and plays a role in regulating monocyte and T cell chemotaxis and thymocyte apoptosis. CCR8 may play a role in lung T cell recruitment in asthma and can serve as an alternative coreceptor to CD4 for HIV-1 infection. The 433H antibody reportedly neutralized the chemotactic response of cultured T cells to CCL1.
The antibody was conjugated to BD Horizon Red 718, which has been developed exclusively for BD Biosciences as a better alternative to Alexa Fluor® 700. BD Horizon Red 718 can be excited by the red laser (628 – 640 nm) and, with an Em Max around 718 nm, it can be detected using a 730/45 nm filter. Due to similar excitation and emission properties, we do not recommend using R718 in combination with APC-R700 or Alexa Fluor® 700.