Cluster of Differentiation 274,also known as CD274, human B7 homolog 1 (B7H1),and programmed death ligand 1 (PDL1),is a type I transmembrane glycoprotein belonging to B7 family of immune proteins which includes other members like B71, B72, B7H2, PDL2 and B7H3. B7H1 contains 2 Ig like domains in its extracellular region and a short cytoplasmic domain, it has been identified as one of two ligands for programmed death1 (PD1)which is a member of the CD28 family of immunoreceptors. The B7H1/PD1 pathway is involved in the negative regulation of immune responses and may play an important role in the regulation of peripheral tolerance. B7-H1 leads to growth of immunogenic tumor growth by increasing apoptosis of antigen specific T cells and may contribute to immune evasion by cancers. Conversely, as a costimulator, B7-H1 induces T-cell proliferation and preferentially the production of interleukin 10 and interferon gamma. Human B7H1 is constitutively expressed in several organs such as heart, skeletal muscle, placenta and lung, and in lower amounts in thymus, spleen, kidney and liver. B7H1 expression is also induced in dendritic cells and keratinocytes after IFNγ stimulation.

·Description
Recombinant Human CD274 produced by transiently transfected human cell is the extracellular domain sequence (Accession#Q9NZQ7)(Phe19-Thr239) of human CD274 fused with a polyhistidine tag at the C-terminus.

·Quality Control
Biological activity:
The ED50 of rHuCD274 is typically 3-10μg/mL as measured by its ability to inhibit antiCD3 antibody induced IL2 secretion in human T lymphocytes
Purity: Greater than 90.0% as determined by:
(a) Analysis by RP-HPLC.
(b) Analysis by reducing and non-reducing SDS-PAGE Silver Stained gel.
Amino-Acid Sequence: Predicted N terminal amino acid is Phe19.
Endotoxin: Less than 0.1ng/μg (1EU/μg) of rHuCD274.

·Formulation
Sterile and Lyophilized from a 0.2 μm filtered solution in PBS.

·Reconstitution
It is recommended to reconstitute the lyophilized rHuCD274 in sterile PBS water not less than 100μg/ml, which can then be further diluted to other aqueous solutions.

·Storage
Lyophilized rHuCD274 although stable at room temperature for 3 weeks, should be stored desiccated below -18°C. Upon reconstitution rHuCD274 should be stored at 4°C between 2-7 days and aliquots of reconstituted samples containing 0.1% BSA are stable up to 3 months below -18°C for future use.
Please avoid freeze-thaw cycles.

Please avoid freeze-thaw cycles.