VSIG IgG Superfamily Members: Potential New Immunotherapeutic Drug Targets

VSIG IgG Family Members for Cancer Immunotherapy

The B7 family and other T cell co-stimulatory/co-inhibitory molecules are widely recognized as therapeutic targets for cancer immunotherapy. V-Set and Immunoglobulin domain containing (VSIG) proteins are members of the immunoglobulin protein superfamily and are increasingly recognized as potential immuno-oncology targets. In fact, R&D Systems scientists have identified VSIG3 as the ligand of VISTA-PD-1H (See poster, 1). Other unpublished results from our in-house research provide further evidence that the VSIG family plays an important role in T cell regulation.

R&D Systems exclusively offers bioactive VSIG proteins in both unlabeled and biotinylated formats for identifying binding partners and the development of novel therapies for immune checkpoint blockade.

Protein Species Source Tag Catalog # Activity
VSIG1 Human NS0 Fc 9708-VS Suppresses IL-17 secretion
Mouse NS0 Fc 9645-VS
VSIG2 Human NS0 Fc 9815-VS Suppresses IL-17 secretion
Mouse NS0 Fc 9598-VS
VSIG3 Human NS0 Fc 9229-VS Binds VISTA/PD-1H (Catalog # 7126-B7)
Human CHO Fc, C-term 10075-VS Suppresses IL-17 secretion
Human CHO Fc, N-term 10074-VS
Mouse NS0 Fc 9367-VS
VSIG4 Human CHO His 9816-VS Suppresses IFN-gamma secretion
Human CHO Fc 9817-VS
Mouse NS0 His 9747-VS
Mouse NS0 Fc 4674-VS Suppresses T cell proliferation
Cynomolgus Monkey HEK293 Fc 10155-VS Suppresses IFN-gamma secretion
VSIG4 Long isoform Human NS0 Fc 4646-VS Binds complement component iC3b
Human NS0 Fc, Biotin BT4646
Human NS0 His 9678-VS Suppresses IFN-gamma secretion
VSIG8 Human CHO Fc 9200-VS Inhibits CD3+ T cell proliferation and IL-2 secretion
Human CHO Fc, Biotin BT9200 Suppresses IL-2 secretion
Mouse NS0 Fc 9204-VS
Human HEK293 Fc 9464-TG Binds CD155/PVR (Catalog # 2530-CD)
Human CHO Fc 7898-TGB Binds CD155/PVR (Catalog # 2530-CD)
Human CHO His 9525-TG Binds CD155/PVR Fc (Catalog # 9174-CD)
Mouse NS0 Fc 7267-TG Binds CD155/PVR (Catalog # 6909-CD)
Cynomolgus Monkey HEK293 Fc 9380-TG Binds CD155/PVR (Catalog # 2530-CD)
VSIG10 Mouse NS0 Fc 9604-VS Suppresses IL-17 secretion
VSIG10L Human HEK293 His 9599-VS Suppresses IFN-gamma Secretion
Recombinant human VSIG3 protein binds to recombinant human VISTA/PD-1H protein Recombinant human VSIG3 protein inhibits anti-CD3 antibody Recombinant human VSIG-10L protein inhibits IFN-gamma secretion.
Recombinant human VSIG3 binds to recombinant human VISTA/PD-1H in a functional binding ELISA. The concentration of VSIG3 that produced 50% optimal binding was 0.25 mg/mL (3.4 nM). Recombinant human VSIG3 (Catalog # 9229-VS) inhibits anti-CD3 antibody induced IL-17 secretion in human PBMCs. The ED50 for this effect is 1-6 ug/mL. Recombinant human VSIG-10L (Catalog # 9600-VS) inhibits IFN-gamma secretion by PBMCs in the presence of anti-CD3 antibody. The ED50 for this effect is 1-6 µg/mL.
Recombinant human VSIG8 protein inhibits anti-CD3 induced human CD3+ T cell proliferation Biotinylated recombinant human VSIG8 protein Recombinant cynomolgus monkey VSIG4 protein.
Recombinant human VSIG8 inhibits anti-CD3 induced human CD3+ T cell proliferation. For more information on VSIG8's role as a coinhibitory ligand, see our poster. Biotinylated recombinant human VSIG8 (Catalog # BT9200) exhibits near identical activity to unlabeled recombinant human VSIG8 (Catalog # 9200-VS). Both proteins inhibit IL-2 secretion by human T cells in the presence of anti-CD3 antibody. The ED50 for this effect is 1-5 μg/mL. Recombinant cynomolgus monkey VSIG4 (Catalog # 10155-VS) was resolved with SDS-PAGE under reducing (R) and non-reducing (NR) conditions showing bands at 67-76 kDa and 130-150 kDa, respectively.


  1. Wang, J. et al. (2019) Immunology. 156:74. Pubmed link

View other Immune-checkpoint blockade targets

Related Pathways

T Cell Co-Signaling Pathway: Ligand-Receptor Interactions

Mechanisms of Regulatory T Cell-Mediated Suppression

Other immune-checkpoint blockade resources:

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