Recombinant Human Cytotoxic T-lymphocyte Protein 4(C-Flag)

Description :

Recombinant Human Cytotoxic T-lymphocyte Protein 4 is produced by our Mammalian expression system and the target gene encoding Lys36-Asp161 is expressed with a Flag tag at the C-terminus.

Formulation :

Lyophilized from a 0.2 um filtered solution of PBS, pH7.4.

Purity :

Greater than 95% as determined by reducing SDS-PAGE.

Endotoxin :

Less than 0.1 ng/ug (1 IEU/ug) as determined by LAL test.

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 米g/ml.
Dissolve the lyophilized protein in ddH2O.
Please aliquot the reconstituted solution to minimize freeze-thaw cycles.

Storage :

Lyophilized protein should be stored at ＜ -20℃, though stable at room temperature for 3 weeks.
Reconstituted protein solution can be stored at 4-7℃ for 2-7 days.
Aliquots of reconstituted samples are stable at ＜ -20℃ for 3 months.

Background :

Cytotoxic Tlymphocyte 4(CTLA-4,CD152), is a type I transmembrane T cell inhibitory molecule that is a member of the Ig superfamily. Human or mouse CTLA4 cDNA encodes 223 amino acids (aa) including a 35 aa signal sequence, a 126 aa extracellular domain (ECD) with one Ig-like V-type domain, a 21 aa transmembrane (TM) sequence, and a 41 aa cytoplasmic sequence.It is widely expressed with highest levels in lymphoid tissues. CD28 and CTLA-4, together with their ligands, B7-1 and B7-2, constitute one of the dominant costimulatory pathways that regulate T and B cell responses. CD28 and CTLA-4 are structurally homologous molecules that are members of the immunoglobulin (Ig) gene superfamily. CTLA4 transmits an inhibitory signal to T cells, whereas CD28 transmits a stimulatory signal. Intracellular CTLA4 is also found in regulatory T Cells and may play an important role in their functions. Tcell activation through the Tcell receptor and CD28 leads to increased expression of CTLA4.