Siglecs: targets for immune regulation and cancer therapy

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.

ProteinSpeciesSourceTagCatalog #Activity
Siglec-1/CD169HumanNS0His5197-SLSupports RBC adhesion
MouseNS0Fc5610-SL
Siglec-2/CD22HumanNS0Fc1968-SLSupports RBC adhesion
HumanCHOFc, Avi-tagAVI1968
HumanNS0Fc, Alexa Fluor® 488AFG1968Binds anti-Siglec-2 / CD22 monoclonal antibody conjugated beads
HumanNS0Fc, Alexa Fluor® 647AFR1968
HumanNS0Fc, Atto 488ATJ1968
HumanNS0Fc, Atto 647NATM1968
HumanCHOHis10191-SLSupports RBC adhesion
HumanCHOHis, Avi-tagAVI10191
MouseNS0Fc2296-SL
Cynomolgus MonkeyHEK293Fc10031-SL
Cynomolgus MonkeyHEK293His9864-SL
RatCHOFc10572-SL
RatCHOHis10571-SL
Siglec-3/CD33HumanNS0Fc1137-SLSupports RBC adhesion
HumanCHOHis, Avi-tagAVI1137
HumanNS0Fc, Alexa Fluor® 488AFG1137Binds anti-Siglec-3 / CD33 monoclonal antibody conjugated beads
HumanNS0Fc, Alexa Fluor® 647AFR1137
HumanNS0Fc, Atto 488ATJ1137
HumanNS0Fc, Atto 647NATM1137
HumanCHOHis10375-SLSupports RBC adhesion
HumanHEK293Fc, Avi-tagAVI10467
MouseNS0Fc10102-SLBinds Siglec H (Caalog # 10264-SH)
Cynomolgus MonkeyCHOFc10885-SLBinds Galectin-3BP/MAC-2BP (Catalog # 2226-GAB)
Cynomolgus MonkeyCHOHis11217-SL 
Siglec-4a/MAGHumanHEK293Fc8940-MGInhibits neurite outgrowth of E13 chick embryonic DRG neurons
MouseNS0Fc8580-MG
RatNS0Fc538-MG
Siglec-5/CD170HumanNS0Fc1072-SLSupports RBC adhesion
Siglec-6/CD327HumanCHOFc2859-SLBinds biotinylated Neu5Ac alpha 2-6GalNAc alpha
Siglec-7/CD328HumanNS0Fc1138-SLSupports RBC adhesion
Siglec-8HumanNS0Fc9045-SLBinds biotinylated Sialyl Lewis X
Siglec-9HumanNS0Fc1139-SLSupports RBC adhesion
Cynomolgus MonkeyHEK293Fc11242-SL
Siglec-10HumanNS0Fc2130-SLBinds biotinylated 6’-Sialyllactose-Polyacrylamide
HumanCHOFc, Avi-tagAVI2130Binds CD52 (Catalog # 9116-CD)
Siglec-11HumanCHOFc3258-SLBinds biotinylated (Neu5Aca2-8)2-Polyacrylamide
Siglec-14HumanNS0Fc4905-SLSupports RBC adhesion
Siglec-15HumanCHOFc9227-SLInhibits anti-CD3 induced IFN-gamma secretion by T cells
HumanCHOHis10698-SL
MouseNS0Fc10101-SLInhibits anti-CD3 induced IL-2 secretion by T cells
MouseNS0His10288-SL
Siglec-EMouseNS0Fc5806-SLBinds biotinylated Neu5Ac alpha 2-6GalNAc alpha -Polyacrylamide
Siglec-FMouseNS0Fc1706-SFSupports RBC adhesion
MouseNS0His10171-SF 
Siglec-GMouseNS0Fc10103-SLBinds biotinylated 6'-Sialylactose-PAA
Siglec-HMouseNS0Fc10264-SHBinds Siglec-3 (Catalog # 10102-SL)
Alexa Fluor® is a registered trademark of Molecular Probes, Inc., Eugene, OR.
Siglec-2/CD22 Fc chimera adhesion with human red blood cells.

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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.

Siglec-15 Fc chimera inhibition of anti-CD3 antibody.

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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.

SDS-PAGE of Siglec-F His-tag.

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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.

References:

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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