Recombinant Human/Cynomolgus T-cell-specific Surface Glycoprotein CD28 is produced by our Mammalian expressionsystem and the target gene encoding Asn19-Pro152 is expressed with a mFc tag at the C-terminus. Accession #: P10747 Known as: CD28; CD28 antigen; CD28 molecule; T-cell-specific surface glycoprotein CD28; Tp44; TP44
制剂(Formulation) Lyophilized from a 0.2 μm filtered solution of PBS, pH 7.4.
质量控制(Quality Control)
Purity: Greater than 95% as determined by reducing SDS-PAGE. Endotoxin: Less than 0.1 ng/ug (1 EU/ug) as determined by LAL test.
Bioactivity-Elisa:
Bioactivity-BLI:
Immobilized Anti-CD28 mAb(Cat#A063) at 2μg/ml (100 μl/well) can bind Human/Cynomolgus CD28-mFc(Cat#CW31). The ED50 of Human/Cynomolgus CD28-mFc(Cat#CW31) is 7.89 ng/ml.
Loaded Anti-Human CD28 mAb-Fc(Cat#GMP-A063) on AHC Biosensor, can bind Human/Cynomolgus CD28-mFc(Cat#CW31) with an affinity constant of 0.001 nM as determined in BLI assay.
复溶(Reconstitution) Always centrifuge tubes before opening. Do not mix by vortex or pipetting. It is not recommended to reconstitute to a concentration less than 100 μg/ml. Dissolve the lyophilized protein in distilled water. Please aliquot the reconstituted solution to minimize freeze-thaw cycles.
保存(Storage) Lyophilized protein should be stored at < -20°C, though stable at room temperature for 3 weeks. Reconstituted protein solution can be stored at 4-7°C for 2-7 days. Aliquots of reconstituted samples are stable at < -20°C for 3 months.
背景(Background) T-cell-specific surface glycoprotein CD28(CD28) is a single-pass typeI membrane protein which contains one Ig-likeV-type (immunoglobulin-like)domain. It belongs to the immunoglobulin(Ig) superfamily. CD28 is one of the molecules expressed on T cells that provide co-stimulatory signals, which are required for T cell activation. CD28 co-stimulation is necessary for CD4 positive T-cell proliferation and survival, interleukin-2 production, and T-helper type-2 development. Human post-thymic regulatory T cells require CD28 co-stimulation to expand and maintain potent suppressive function in vivo. Apoptosis plays a key role in the age-related decline of CD28 expression and in immunosenescence. CD28 is the receptor for CD80(B7.1) and CD86(B7.2). When activated by Toll-like receptor ligands, the CD80 expression is upregulated in antigen presenting cells(APCs). The CD86 expression on antigen presenting cells is constitutive. CD28 is the only B7 receptor constitutively expressed on naive T cells.