CD163 Monoclonal Antibody (eBioGHI/61 (GHI/61)), eBioscience™, Invitrogen™

Description

• The eBioGHI/61 MAb reacts with human CD163 (Haemoglobin Scavenger Receptor, M130), a member of the macrophage scavenger receptor family
• CD163 is expressed by tissue macrophages, circulating blood monocytes, and some reports suggest that it may also be expressed by haematopoietic progenitor cells
• CD163 functions as a high affinity scavenger receptor for the complex of haemoglobin and haptoglobin which forms to clear haemoglobin from the blood
• The high affinity for CD163 is specific for the haemoglobin-haptoglobin complex, whereas haemoglobin or haptoglobin display no to low affinity toward CD163
• Upon ligand binding, CD163 initiates signal transduction which leads to the production of IL-6 and IL-10
• Furthermore, it has been demonstrated that cytokines such as IL-6 and IL-10 can induce expression of CD163, whereas proinflammatory stimuli, such as LPS or TNF alpha, can cause shedding of a soluble form of CD163, whose function is unclear
• CD163 (M130 antigen, Ber-Mac3, Ki-M8, SM4) is a 130 kDa membrane glycoprotein, a member of the scavenger receptor cysteine-rich superfamily, and a receptor for the hemoglobin-haptoglobin complex
• CD163 protects tissues from free hemoglobin-mediated oxidative damage, and may play a role in the uptake and recycling of iron, via endocytosis of hemoglobin/haptoglobin and subsequent breakdown of heme
• CD163 is expressed exclusively on the cell surface of human monocytes and macrophages that evolve predominantly in the late phase of inflammation
• Specifically, CD163 is present on all circulating monocytes and most tissue macrophages except those found in the mantle zone and germinal centers of lymphoid follicles, interdigitating reticulum cells and Langerhan's cells
• CD163 is present on all CD14 positive monocytes, most CD64 positive monocytes, and shows higher expression on CD16 positive monocytes
• CD163 is upregulated on mononuclear phagocytes by IL-10, IL-6 and dexamethasone
• Lipopolysaccharide (LPS) and phorbol myristate acetate (PMA) both induce shedding of CD163 from the cell surface into plasma or cell supernatant
• CD163 binds hemoglobin/haptoglobin complexes in a calcium-dependent and pH-dependent manner, and exhibits a higher affinity for complexes of hemoglobin and multimeric haptoglobin of HP1F phenotype than for complexes of hemoglobin and dimeric haptoglobin of HP1S phenotype
• Further, CD163 also induces a cascade of intracellular signals that involves tyrosine kinase-dependent calcium mobilization, inositol triphosphate production and secretion of IL6 and CSF1.