Dectin 2, Recombinant, Human (CLEC6A, CLECSF10, NKCL)

Dectin-2, also known as CLEC6A, CLECSF10, and NKCL, belongs to the C-type lectin family of transmembrane immune regulatory glycoproteins. Dectin-2, plus CLEC4A-E constitute a subgroup of molecules that exhibit approximately 40% aa sequence identity in their extracellular domains (ECD), and have a conserved cysteine spacing in their carbohydrate recognition domains (CRD) (1, 2). Mature human Dectin-2 is a type II transmembrane protein with a short cytoplasmic tail, a transmembrane segment, and a 168 aa ECD with a stalk region and one CRD (3, 4). Within the ECD, human Dectin-2 shares 71% and 75% aa sequence identity with bovine and mouse Dectin-2, respectively. An alternately spliced beta isoform has a deletion of portions of the transmembrane and cytoplasmic regions (5). Full length Dectin-2 is a 27 kD molecule that is expressed on monocytes, tissue macrophages, and activated CD4+ T cells (4-6). The CRD of Dectin-2 contains an EPN motif which is characteristic of calcium-dependent mannose-binding lectins. Dectin-2 selectively interacts with high mannose structures in the Man9GlcNAc2 configuration (7). It mediates the recognition of a variety of microorganisms, particularly the filamentous forms of yeast and fungii (7, 8). The short cytoplasmic tail does not contain signaling motifs but mediates association with the ITAM-containing Fc receptor gamma subunit on macrophages (8). Ligation of Dectin-2 induces tyrosine phosphorylation of the gamma subunit, activation of NFkappaB, and enhanced release of TNF-alpha and IL-1ra (8). Macrophage Dectin-2 is upregulated in vivo by inflammatory stimuli and UV-B irradiation (5, 6, 9). Dectin-2 is known to participate in UV-induced immunosuppression by interacting with CD4+ CD25+ regulatory T cells, which then induce dendritic cells to release IL-4, IL-10, and TGF-beta (10). Source: Human CD33 Signal Peptide (Met 1-Ala 16), HHHHHH, Human Dectin-2 (Thr 46-Leu 209). A DNA sequence encoding the signal peptide from human CD33 was fused to the N-terminal 6X histidine-tagged extracellular domain of human Dectin-2 (Thr 46-Leu 209) (Accession # NP_001007034, Q6EIG7). The chimeric protein was expressed in a mouse myeloma cell line, NS0. Molecular Mass: Based on N-terminal amino acid sequencing, the recombinant human Dectin-2 begins with the histidine tag. It has a predicted molecular mass of approximately 19.7 kD. As a result of glycosylation, the recombinant human Dectin-2 migrates as an approximately 23 kD protein in SDS-PAGE under reducing conditions. Endotoxin Level: < 1.0 EU per 1 µg of the protein as determined by the LAL method. Activity: Measured by its ability to bind biotinylated alpha-D-Mannose-PAA in a functional ELISA. Reconstitution: It is recommended that sterile PBS be added to the vial to prepare a working stock solution of no less than 100ug/ml. The carrier-free protein should be used immediately upon reconstitution to avoid losses in activity due to non-specific binding to the inside surface of the vial. For long term storage as a dilute solution, a carrier protein (e.g. 0.1% HSA or BSA) should be added to the vial. Storage and Stability: Lyophilized samples are stable for up to twelve months at -20°C. Upon reconstitution, this protein, in the presence of a carrier protein, can be stored under sterile conditions at 2-8°C for one month or at -20°C in a manual defrost freezer for three months without detectable loss of activity. Avoid repeated freeze-thaw cycles.