CD163 (Cluster of Differentiation 163) is a human protein encoded by the CD163 gene. It has also been shown to mark cells of monocyte/macrophage lineage.
The molecular size is 130 kDa. The receptor belongs to the scavenger receptor cysteine rich family type B and consists of an 1048 amino acid residues extracellular domain, a single transmembrane segment and a cytoplasmic tail with several splice variants.
CD163 is a scavenger receptor for the hemoglobin-haptoglobin complex.
A soluble form of the receptor exists in plasma, commonly denoted sCD163. It is generated by ectodomain shedding of the membrane bound receptor. sCD163 is upregulated in a large range of diseases inflammatory diseases including type 2 diabetes, macrophage activation sickness, Tangier's disease, reumatoid arthritis etc.