Description : |
B7-H1, also called programmed death ligand (PD-L1) is a protein in the B7 family of immune proteins. PD-L1 binds to its receptor, PD-1, found on activated T cells, B cells, and myeloid cells, to modulate activation or inhibition. Engagement of PD-L1 with PD-1 on T cells delivers a signal that inhibits TCR-mediated activation of IL-2 production and T cell proliferation. The mechanism involves inhibition of ZAP-70 phosphorylation and its association with CD247. PD-L1 signaling attenuates PKC-8 activation loop phosphorylation (resulting from TCR signaling), necessary for the activation of transcription factors NF-κB and AP-1 and for the production of IL-2. Upon IFN-γ stimulation, PD-L1 is expressed on T cells, NK cells, macrophages, myeloid DCs, B cells, epithelial cells, and vascular endothelial cells. Type I interferons can also upregulate PD-L1 on murine hepatocytes, monocytes, DCs, and tumor cells. It appears that upregulation of PD-L1 is a mechanism that cancers can employ to evade the host immune system as patients with higher expression levels of PD-L1 had a significantly poorer prognosis. |
Source : |
Mammalian cells |
Species : |
Mouse |
Form : |
Lyophilized. This recombinant protein was 0.2 µm filtered and lyophilized from modified Dulbecco’s phosphate buffered saline (1X PBS) pH 7.2 – 7.3 with no calcium, magnesium, or preservatives. |
Bio-activity : |
The biological activity of Mouse B7-H1 was determined by its ability to inhibit anti-CD3 induced proliferation of 72 hour PHA T cell blast. The expected ED50 for this effect is typically 2.5 - 10 μg/mL. |
Molecular Mass : |
The predicted molecular weight of Recombinant Mouse B7-H1 is Mr 51.3 kDa (monomer). However, the actual molecular weight as observed by migration on SDS Page is Mr 75-85 kDa. |
Endotoxin : |
<1.0 EU/µg as determined by the LAL method |
Purity : |
>90% by SDS-PAGE and analyzed by silver stain. |
Storage : |
This lyophilized protein is stable for six to twelve months when stored desiccated at -20°C to -70°C. After aseptic reconstitution, this protein may be stored at 2°C to 8°C for one month or at -20°C to -70°C in a manual defrost freezer. Avoid Repeated Freeze Thaw Cycles. |