CD5L

Description

The CD5L (CD5 molecule like) is a protein-coding gene located on chromosome 1.

CD5 antigen-like is a protein (also known as AIM Apoptosis Inhibitor of Macrophages) that in humans is encoded by the CD5L gene.

CD5L is a secreted protein that plays a crucial role in regulating lipid synthesis. It is primarily expressed by macrophages in lymphoid and inflamed tissues and participates in inflammatory responses, such as infection or atherosclerosis. CD5L can inhibit lipid droplet size in adipocytes, and upon integration into mature adipocytes through CD36-mediated endocytosis, it associates with cytosolic FASN, hindering fatty acid synthase activity and leading to lipolysis, the breakdown of triacylglycerols into glycerol and free fatty acids. CD5L-induced lipolysis is linked to the progression of obesity, contributing to obesity-associated inflammation by recruiting inflammatory macrophages into adipose tissues, ultimately causing insulin resistance and obesity-related metabolic disorders. CD5L's regulation of intracellular lipids directly affects transcription regulation through nuclear receptors ROR-gamma (RORC). CD5L acts as a key regulator of the metabolic switch in T-helper Th17 cells, controlling the expression of pro-inflammatory genes in these cells by modifying lipid content and limiting the synthesis of cholesterol ligand for RORC, the master transcription factor in Th17-cell differentiation. CD5L is primarily present in non-pathogenic Th17 cells, where it reduces the content of polyunsaturated fatty acyls (PUFA), impacting two metabolic proteins, MSMO1 and CYP51A1, which synthesize ligands for RORC, thereby limiting RORC activity and the expression of pro-inflammatory genes. CD5L contributes to obesity-associated autoimmunity by associating with IgM, interfering with the binding of IgM to Fcalpha/mu receptor, and promoting the development of long-lived plasma cells that produce high-affinity IgG autoantibodies. CD5L also acts as an inhibitor of apoptosis in macrophages, aiding in macrophage survival from the apoptotic effects of oxidized lipids in cases of atherosclerosis. CD5L is involved in the early response to microbial infection against various pathogens by acting as a pattern recognition receptor and promoting autophagy.

CD5L is also known as AIM, API6, CT-2, PRO229, SP-ALPHA, Spalpha, hAIM.

Associated Diseases

WES Whole Exome Sequencing