CLEC9A

C-type lectin 9 family A member (CLEC9A), also known as dendritic cell-NK cell lectin cluster receptor 1 (DNCR1), is a dendritic cell surface molecule discovered in 2008, belonging to non-classical type II Transmembrane C-type lectin-like receptor (CLR). The CLEC9A molecule consists of three parts: N-terminal cytoplasmic domain, transmembrane domain and C-terminal extracellular domain. The extracellular domain includes neck region and a C-type lectin-like domain. The expression of CLEC9A molecule is highly DC-restricted. Mouse CLEC9A is mainly expressed on the surface of CD8α+DC and CD103+CD11b- ordinary dendritic cells. In human peripheral blood, CLEC9A is mainly expressed on blood dendritic cell antigen 3 (BDC4A3). Positive myeloid dendritic cells (mDC), namely BDCA3+mDC surface. Human BDCA3+CLEC9A+DC as an independent DC subset, equivalent to mouse CD8α+DC, can mediate endocytosis, cross-present antigens to CD8+ T cells, and stimulate cytotoxic T lymphocyte (CTL) responses in vivo.