Identification of the haemoglobin scavenger receptor
| Autor: | Ole Sonne, Christian Jacobsen, Jonas Heilskov Graversen, Søren K. Moestrup, Mette Kristiansen, Hans Jürgen Hoffman, S. K.Alex Law |
|---|---|
| Rok vydání: | 2001 |
| Předmět: |
Erythrocytes
Molecular Sequence Data Antigens Differentiation Myelomonocytic Receptors Cell Surface CHO Cells Endocytosis Transfection Hemoglobins Antigens CD Cricetinae polycyclic compounds Animals Humans Scavenger receptor skin and connective tissue diseases Receptor Multidisciplinary biology Haptoglobins Macrophages Haptoglobin Acute-phase protein food and beverages Biochemistry Heme Oxygenase (Decyclizing) biology.protein Hemoglobin CD163 |
| Zdroj: | Nature. 409(6817) |
| ISSN: | 0028-0836 |
| Popis: | Intravascular haemolysis is a physiological phenomenon as well as a severe pathological complication when accelerated in various autoimmune, infectious (such as malaria) and inherited (such as sickle cell disease) disorders1. Haemoglobin released into plasma is captured by the acute phase protein haptoglobin, which is depleted from plasma during elevated haemolysis1. Here we report the identification of the acute phase-regulated and signal-inducing macrophage protein, CD163, as a receptor that scavenges haemoglobin by mediating endocytosis of haptoglobin–haemoglobin complexes. CD163 binds only haptoglobin and haemoglobin in complex, which indicates the exposure of a receptor-binding neoepitope. The receptor–ligand interaction is Ca2+-dependent and of high affinity. Complexes of haemoglobin and multimeric haptoglobin (the 2-2 phenotype) exhibit higher functional affinity for CD163 than do complexes of haemoglobin and dimeric haptoglobin (the 1-1 phenotype). Specific CD163-mediated endocytosis of haptoglobin–haemoglobin complexes is measurable in cells transfected with CD163 complementary DNA and in CD163-expressing myelo-monocytic lymphoma cells. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|