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 Our own unpublished observations reveal that other VSIG proteins also negatively regulate T cell function (see data below).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. 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. 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. 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 |