Host C-type lectin receptor (CLR)

Host C-type lectin receptors (CLRs) are a large family of calcium-dependent carbohydrate-binding proteins expressed as membrane-bound or soluble forms on various immune cells, primarily dendritic cells, macrophages, neutrophils, and natural killer (NK) cells[1][2][7]. CLRs function as pattern-recognition receptors (PRRs) that detect pathogen-associated molecular patterns (PAMPs) and damage-associated molecular patterns (DAMPs), mediating innate and adaptive immune responses[1][2][5][7]. They play central roles in antigen uptake, processing, and presentation; modulation of T helper cell differentiation; production of inflammatory mediators; and maintenance of tissue homeostasis[1][3][6]. Key members include Dectin-1, Dectin-2, DC-SIGN, Mincle, CLEC9A, and killer lectin-like receptors (KLRs) associated with NK cells[2][7]. CLR engagement influences resistance to pathogens such as fungi, viruses, and bacteria, and their dysregulation is implicated in major diseases ranging from infections and allergy to cancer and autoimmunity[1][6][8]. Members of the CLR family differ in ligand specificity, cellular distribution, and downstream signaling pathways, which determines distinct biological outcomes – from protective cytokine responses to immune escape mechanisms exploited by pathogens and tumors[1][4][5]. Therapeutic strategies targeting CLRs are under active investigation, mainly in immunotherapy, vaccine design, and inflammation modulation[1][4][6][8]. Some CLRs, such as MBL, also function as soluble proteins and are involved in complement activation. Safety concerns mainly relate to hypersensitivity, excessive immune activation, and immune suppression within the tumor microenvironment[6]. No major misspelling or error is present in the designation "Host C-type lectin receptors," although the term refers to a family rather than an individual molecule. For structured data, individual members (e.g., Dectin-1, DC-SIGN) may be separated as specific targets.

Other names

C-type lectinCLECC-type lectin-like receptorCTLRkiller lectin-like receptorDectin-1 (member)Dectin-2 (member)DC-SIGN (member)Mincle (member)L-SIGNMBLLOX-1CLEC9ACLEC12ANKRP1

Ligand binding leads to immune activation via signaling cascades (e.g., Syk/CARD9 pathway, NF-κB activation). Induce cytokine profile shifts, T helper cell polarization (Th1, Th2, Th17, Tfh). Antigen uptake, cross-presentation to T cells. Modulation of type I interferon responses. Promotion/suppression of inflammation via downstream signaling[1][5][6][8].