CD28, also known as T-cell-specific surface glycoprotein CD28 isoform 1, is one of the proteins expressed on T cells that provide co-stimulatory signals required for T cell activation and survival. T cell stimulation through CD28 in addition to the T-cell receptor (TCR) can provide a potent signal for the production of various interleukins (IL-6 in particular). CD28/B7 interaction has been shown to prevent apoptosis of activated T cells via the up-regulation of bcl-XL. It ligation has also been shown to regulate Th1/Th2 differentiation. Recombinant protein corresponding to aa24-188 from human CD28, fused to hIgG-His-Tag at C-terminal, expressed in insect cell. Molecular Weight: ~42.4kD (376aa), 40-57kD (SDS-PAGE under reducing conditions) Amino Acid Sequence: ADPNKILVKQ SPMLVAYDNA VNLSCKYSYN LFSREFRASL HKGLDSAVEV CVVYGNYSQQ LQVYSKTGFN CDGKLGNESV TFYLQNLYVN QTDIYFCKIE VMYPPPYLDN EKSNGTIIHV KGKHLCPSPL FPGPSKPLEP KSCDKTHTCP PCPAPELLGG PSVFLFPPKP KDTLMISRTP EVTCVVVDVS HEDPEVKFNW YVDGVEVHNA KTKPREEQYN STYRVVSVLT VLHQDWLNGK EYKCKVSNKA LPAPIEKTIS KAKGQPREPQ VYTLPPSRDE LTKNQVSLTC LVKGFYPSDI AVEWESNGQP ENNYKTTPPV LDSDGSFFLY SKLTVDKSRW QQGNVFSCSV MHEALHNHYT QKSLSLSPGK HHHHHH Storage and Stability: May be stored at 4C for short-term only. Aliquot to avoid repeated freezing and thawing. Store at -20C. Aliquots are stable for 6 months after receipt at -20C. For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap. Further dilutions can be made in assay buffer.
