CTLA-4 (cytotoxic T-lymphocyte associated protein4, designated CD152), is a type I transmembrane T cell inhibitory molecule that is a member of the Ig superfamily. Human or mouse CTLA-4 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 found as a covalent homodimer of 41-43 kDa Within the ECD, human CTLA-4 shares 68%, 71% and 8386% aa sequence identity with mouse, rat and porcine/bovine/rabbit/feline/canine CTLA-4, respectively. A 174 aa form that lacks TM and cytoplasmic sequences (sCTLA-4) is possibly secreted (3-5). Isoforms of 56-79 aa that mainly contain parts of the cytoplasmic domain are reported. In mouse, an isoform lacking the Ig-like domain has ligand-independent inhibitory activity and is termed liCTLA-4. CD28, which is structurally related to CTLA-4, is constitutively expressed on naïve T cells and promotes T cell activation when engaged by B7-2 on antigen-presenting cells (APC) within the immunological synapse (IS) . In contrast, CTLA-4 is recruited from intracellular vesicles to the IS beginning 1-2 days after T cell activation. It forms a linear lattice with B7-1 on APC, inducing negative regulatory signals and ending T cell activation .

 

产品性质

别名（Synonyms）	CTLA4; CD152; ICOS; CELIAC3; GRD4; GSE; ALPS5; IDDM12
Uniprot No.	P16410-1
表达区间及表达系统（Source）	Recombinant Human CTLA-4/CD152 Protein is expressed from HEK293 Cells with His tag at the C-terminal. It contains Lys36-Asp161.
分子量(Molecular Weight)	The protein has a predicted MW of 14.3 kDa. Due to glycosylation, the protein migrates to 28-35 kDa based on Tris-Bis PAGE result.
外观(Physical Appearance）	Sterile Filtered White lyophilized (freeze-dried) powder.
纯度（Purity）	> 95% as determined by SDS-PAGE and HPLC
活性（Activity）	1.ELISA Data：Immobilized Human CTLA-4, His Tag at 0.5μg/ml (100μl/Well) on the plate. Dose response curve for Anti-CTLA-4 Antibody, hFc Tag with the EC50 of 20.1ng/ml determined by ELISA. 2.ELISA Data：Immobilized Human B7-1, hFc Tag at 0.5μg/ml (100μl/Well) on the plate. Dose response curve for Human CTLA-4, His Tag with the EC50 of 66ng/ml determined by ELISA.
内毒素（Endotoxin）	< 1.0 EU per 1μg of the protein by the LAL method.
制剂（Formulation）	Lyophilized from 0.22 μm filtered solution in PBS (pH 7.4). Normally 5% trehalose is added as protectant before lyophilization.
复溶（Reconstitution）	Centrifuge tubes before opening. Reconstituting to a concentration more than 100 μg/mL is recommended (usually we use 1 mg/mL solution for lyophilization). Dissolve the lyophilized protein in distilled water.

 

运输与保存方法

冰袋运输。-20℃至-80℃保存，一年有效期。

复溶后，-20 至 -80°C，在未开封状态下保存 3-6 个月。复溶后，2-8°C 保存 2-7 天。

建议第一次使用时分装冻存，避免反复冻融。

 

注意事项

1. 避免反复冻融。

2. 为了您的安全和健康，请穿实验服并戴一次性手套操作。

3. 本产品仅作科研用途！

 

产品数据

Tris-Bis PAGE

HB220624