Siglecs (sialic acid-binding immunoglobulin-type lectins) are receptors predominantly located on the surface of hematopoietic cells. Recent publications highlight the important roles Siglecs play in tumor immunosurveillance making them attractive anti-cancer drug targets. Inhibitory receptors Siglec-7 and Siglec-9 are expressed on NK cells and recognize tumor-associated sialosides (1,2). Also, Siglec-15 (Catalog # 9227-SL) was identified as an immune suppressor by engaging an unknown receptor on T cells. Similar to PD-L1/PD-1 immune checkpoint blockade, Siglec-15 may be a potential target for cancer immunotherapy (3).
Siglecs interact with an array of linkage-specific sialic acids on a glycan structure expressed on host cells, as well as pathogens. So far, there are 15 different human and 9 murine Siglecs. Each type of Siglec generally recognizes a particular set of sialylated glycan containing differently linked sialic acid molecules (4,5). On the cytoplasmic side, most Siglecs have immune receptor tyrosine-based inhibition motifs (ITIM), which initiate signaling cascades resulting in downregulation of proinflammatory responses.
R&D Systems provides you with the widest selection of high-quality, bioactive Siglecs on the market. Can’t find what you are looking for? The R&D Systems Custom Protein Development Team can work with you to create a customized protein solution to meet your specific research needs.
| Recombinant Cynomolgus Monkey Siglec‑2/CD22 Fc Chimera (Catalog # 10031-SL) supports the adhesion of human red blood cells. The ED50 for this effect is 0.07-0.42 ug/mL.
||Recombinant Human Siglec-15 Fc Chimera (Catalog # 9227-SL) inhibits anti-CD3 antibody induced IFN-gamma secretion by human T cells. The ED50 for this effect is 1-10 μg/mL.
||2 μg/lane of Recombinant Mouse Siglec‑F His-tag (Catalog # 10171-SF)was resolved with SDS-PAGE under reducing (R) and non-reducing (NR) conditions and visualized by Coomassie® Blue staining, showing bands at 59-68 kDa.
1. Jandus, C. et al. (2014) J. Clin. Investig. 124:1810.
2. Stanczak, M.A. et al. (2018) J. Clin. Investig. 128:4912.
3. Wang, J. et al. (2019) Nat. Med. 25:656.
4. Bornhöfft, K.F. et al. (2018) Dev. Comp. Immunol. 86:219.
5. Zhou, J.Y. et al. (2018) Trends Immunol. 39:523.
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