VISTA (human):COMP (mouse) (rec.) (His)
Method: Human CD4+ T cells are activated with coated anti-CD3 (human) (2.5µg/ml) and incubated for 5 days with VISTA (human):COMP (mouse) (rec.) (His) or Control protein (Prod. No. AG-35B-0007) (coated at 10µg/ml). TNF-α is measured from cell supernatants using the Cymax TNF-α (human) ELISA Kit (Prod. No. YIF-LF-EK0193).
|Synonyms||V-type Immunoglobulin Domain-containing Suppressor of T Cell Activation; Platelet Receptor Gi24; Stress-induced Secreted Protein-1; Sisp-1; V-set Domain-containing Immunoregulatory Receptor|
|Source/Host||HEK 293 cells|
The extracellular domain of human VISTA (aa 33-194) is fused at the C-terminus to the domain of the mouse cartilage oligomeric matrix protein (COMP) (aa 28-72) and to a His-tag.
|MW||~40-55kDa (SDS-PAGE) and >500kDa (Size Exclusion Chromatography (SEC))|
|Endotoxin Content||<0.01EU/μg purified protein (LAL test).|
|Concentration||1mg/ml after reconstitution.|
|Reconstitution||Reconstitute with 50μl sterile water.|
|Formulation||Lyophilized. Contains PBS.|
|Other Product Data||
UniProt link Q9H7M9: VISTA (human)
|Shipping and Handling|
|Short Term Storage||+4°C|
|Long Term Storage||-20°C|
After reconstitution, prepare aliquots and store at -20°C.
Avoid freeze/thaw cycles.
PBS containing at least 0.1% BSA should be used for further dilutions.
|Use/Stability||Stable for at least 6 months after receipt when stored at -20°C.|
|Product Specification Sheet|
Human VISTA is a 55 to 65kDa type I Ig membrane protein with the extracellular domain homologous to PD-L1. VISTA is mainly expressed on hematopoietic tissues (spleen, thymus and bone marrow) and on myeloid cells with lower expression on CD4+ and CD8+ T cells. VISTA is a new negative checkpoint regulator that potently suppresses T cell activation. Overexpression of VISTA on tumors inhibits the protective anti-tumor immunity and blockade of VISTA enhances antitumor immunity in multiple tumor models. VISTA on APC delivers negative signaling to T cells via a yet-to-identify binding partner on T cells. Recently, it has been reported that the recombinant VISTA protein needs to be multimerized to be active as soluble ligand. The protein VISTA (human):COMP (mouse) (with the extracellular domain of VISTA (human) fused to the pentamerization domain from the cartilage oligomeric matrix protein (COMP)), but not VISTA-Fc, functions as an immunosuppressive agonist in vivo inhibiting the proliferation of CD4+ T cells.
- VISTA.COMP - an engineered checkpoint receptor agonist that potently suppresses T cell-mediated immune responses: A. Prodeus, et al.; JCI Insight 2, e94308 (2017)