VSIG IgG Superfamily Members: Data Supports Their Potential as Immunotherapeutic Drug Targets

The B7 family and other T cell co-stimulatory/co-inhibitory molecules are widely recognized as therapeutic targets for cancer immunotherapy. Many of these are members of the large immunoglobulin superfamily. V-Set and Immunoglobulin domain containing (VSIG) proteins are members of the immunoglobulin protein superfamily and are increasingly recognized as potential immuno-oncology targets. Perhaps the best-known member, VSIG9/TIGIT, has T cell and NK cell inhibitory function, while VSIG4 can negatively regulate T cell proliferation and IL-2 production. Our own unpublished observations reveal that other VSIG proteins also negatively regulate T cell function (see data below).

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.

VSIG3-induced Immunosuppression
VSIG3-induced Immunosuppression. Recombinant Human VSIG3 Fc Chimera (Catalog # 9229-VS) inhibits anti-CD3 antibody induced IL-17 secretion in human PBMCs. The ED50 for this effect is 1-6 ug/mL.
VSIG10L-induced Immunosuppression
VSIG10L-induced Immunosuppression. Recombinant Human VSIG-10L Fc Chimera (Catalog # 9600-VS) inhibits IFN-gamma
secretion by human peripheral blood
mononuclear cells in the presence of anti-CD3 antibody. The ED50 for this effect is 1-6 µg/mL.
Biotinylated and Unlabeled VSIG8 Suppress IL-2 Secretion
Biotinylated and Unlabeled VSIG8 Suppress IL-2 Secretion. Recombinant Human VSIG-8 Fc Chimera (Catalog # 9200-VS) inhibits IL-2 secretion by human T cells in the presence of anti-CD3 antibody. The ED50 for this effect is 1-5 μg/mL. Highlighting its specificity, Biotinylated Recombinant Human VSIG-8 Fc (Catalog # BT9200; Coming Soon) exhibits similar activity.

Bioactive Recombinant VSIG Proteins Available from R&D Systems

Proteins/Tag  Species Catalog # Activity
VSIG1/Fc Human 9708-VS Suppresses IL-17 secretion 
VSIG1/Fc Mouse 9645-VS Suppresses IL-17 secretion 
VSIG2/Fc Human 9815-VS (Coming soon) Suppresses IL-17 secretion
VSIG2/Fc Mouse 9598-VS Suppresses IL-17 secretion
VSIG3/Fc Human 9229-VS Suppresses IL-17 secretion
VSIG3/Fc Mouse 9367-VS Suppresses IL-17 secretion
VSIG4 aa20-189/C-His Human 9816-VS Suppresses IFN-gamma Secretion
VSIG4 aa20-189/Fc Human 9817-VS Suppresses IFN-gamma Secretion
VSIG4 aa20-283/Fc Human 4646-VS Binds complement component iC3b
Biotinylated VSIG4 aa20-283/Fc Human BT4646 Binds complement component iC3b
VSIG4/His Mouse 9747-VS Suppresses IFN-gamma Secretion
VSIG4/Fc Mouse 4674-VS Suppresses T cell proliferation
VSIG8/Fc Human 9200-VS Suppresses IL-2 secretion
Biotinylated VSIG8/Fc Human BT9200 (Coming Soon) Suppresses IL-2 secretion
VSIG-8/mFc Mouse 9204-VS Suppresses IL-2 secretion
VSIG-9/TIGIT(T103)/Fc Human 9464-TG Binds CD155/PVR
VSIG-9/TIGIT/Fc Human 7898-TGB (Coming Soon) Binds CD155/PVR
VSIG-9/TIGIT/His Human 9525-TG (Coming Soon) Binds CD155/PVR
VSIG-9/TIGIT/Fc Mouse 7267-TG Binds CD155/PVR
VSIG-9/TIGIT/Fc Cynomolgus 9380-TG Binds CD155/PVR
VSIG-10/Fc Mouse 9604-VS Suppresses IL-17 secretion
VSIG-10L/His Human 9599-VS Suppresses IFN-gamma Secretion
VSIG-10L/Fc Human 9600-VS Suppresses IFN-gamma Secretion
TIGIT/mFc Mouse 7267-TG Binds CD155/PVR