The Dectin-2 family of C-type lectin-like receptors: an update

Abstract

Myeloid and non-myeloid cells express members of the C-type lectin-like receptor (CTLR) family, which mediate crucial cellular functions during immunity and homeostasis. Of relevance here is the dendritic cell-associated C-type lectin-2 (Dectin-2) family of CTLRs, which includes blood dendritic cell antigen 2 (BDCA-2), dendritic cell immunoactivating receptor (DCAR), dendritic cell immunoreceptor (DCIR), Dectin-2, C-type lectin superfamily 8 (CLECSF8) and macrophage-inducible C-type lectin (Mincle). These CTLRs possess a single extracellular conserved C-type lectin-like domain and are capable of mediating intracellular signalling either directly, through integral signalling domains, or indirectly, by associating with signalling adaptor molecules. These receptors recognize a diverse range of endogenous and exogenous ligands, and can function as pattern recognition receptors for several classes of pathogens including fungi, bacteria and parasites, driving both innate and adaptive immunity. In this review, we summarize our knowledge of each of these receptors, highlighting the exciting discoveries that have been made in recent years.

Fig. 1.

The Dectin-2 cluster of C-type lectins. The Dectin-2 family of C-type lectin receptors are encoded at the telomeric end of the NK gene cluster on human chromosome 12 (A) and mouse chromosome 6 (B). (C) Schematic representation of signal transduction pathways induced by the various Dectin-2 family CTLRs. BLNK, B-cell linker protein; BTK, Bruton’s tyrosine kinase; TM, transmembrane.