Article

CD163 and its expanding functional repertoire.

Department of Biochemistry, JSS Medical College, JSS University, Mysore, India.
Clinica chimica acta; international journal of clinical chemistry (impact factor: 2.54). 04/2012; 413(7-8):669-74. DOI:10.1016/j.cca.2012.01.028 pp.669-74
Source: PubMed

ABSTRACT Macrophages are key players of the immune system and express a variety of surface receptors. CD163 is one such receptor which belongs to the scavenger receptor cysteine-rich super family (SRCR-SF) class B. It has four isoforms which differ in the structure of their cytoplasmic domains and putative phosphorylation sites. Expression of CD163 is tightly regulated with a general tendency of anti-inflammatory signals to induce its synthesis, while pro-inflammatory signals downregulate its expression. Previously the molecule has been shown to act as a receptor for hemoglobin-haptoglobin complexes. However, it also plays a crucial role in the control of inflammatory processes by induction of anti-inflammatory pathways. Soluble CD163, which is generated via ectodomain shedding, serves as a potential diagnostic tool in a variety of disease states, such as inflammation, atherosclerosis, transplant rejection and carcinoma. Recently, CD163 has been identified as a promising target for cell directed therapy. In this review we aim to summarize the current knowledge of CD163.

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Keywords

anti-inflammatory pathways
 
anti-inflammatory signals
 
carcinoma
 
crucial role
 
cytoplasmic domains
 
disease states
 
general tendency
 
hemoglobin-haptoglobin complexes
 
inflammatory processes
 
potential diagnostic tool
 
pro-inflammatory signals downregulate
 
promising target
 
putative phosphorylation sites
 
receptor
 
scavenger receptor cysteine-rich super family
 
SRCR-SF
 
surface receptors
 
transplant rejection