Blood dendritic cell antigen 2 receptor (BDCA-2)

Blood dendritic cell antigen 2 (BDCA-2, also known as CLEC4C or CD303) is a C-type lectin receptor expressed specifically on plasmacytoid dendritic cells (pDCs). BDCA-2 plays a central role in regulating the production of type I interferons, particularly IFN-α, in response to nucleic acid sensing by TLR9. Heparin, both exogenous (clinical) and endogenous (plasma-derived), acts as a ligand for BDCA-2, inducing inhibition of TLR9-dependent IFN-α production. There is also an activation-dependent soluble form of BDCA-2 (solBDCA-2) which acts as a decoy for heparin, effectively antagonizing its inhibition and promoting IFN-α secretion in certain disease states. Dysregulation of this heparin–BDCA-2 pathway is implicated in autoimmune and infectious diseases where type I IFN plays a pathogenic role[1][2].

Other names

CD303CLEC4Cblood dendritic cell antigen 2

Heparin binds to BDCA-2 and inhibits Toll-like receptor 9 (TLR9)-driven type I interferon (IFN-α) production in pDCs\nSoluble BDCA-2, generated during activation, acts as a heparin antagonist and reverses inhibition