Active Recombinant Human CTLA4 protein, Fc/Avi-tagged, Biotinylated

• Cat.No.: CTLA4-051H
• Product Overview: Biotinylated Recombinant Human CTLA4(Ala37-Phe162) protein, fused to Fc/Avi tag at the C-terminus, was expressed in HEK293 cells .

Specification

• Description: CTLA-4 (cytotoxic T-lymphocyte associated protein-4, designated CD152), is a type I transmembrane T cell inhibitory molecule that is a member of the Ig
  superfamily (1, 2). 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 Iglike 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 (2) Within the
  ECD, human CTLA-4 shares 68%, 71% and 83-86% 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 (6). 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) (1, 7, 8). In contrast, CTLA-4 is recruited from intracellular vesicles to the IS beginning 1-2 days after T cell activation (2, 7, 8). It forms a linear lattice
  with B7-1 on APC, inducing negative regulatory signals and ending T cell activation (9). Abatacept, a therapeutic human CTLA-4-Ig fusion protein (trade name Orencia),
  competes with CD28 for B7-1 and B7-2 binding and has been used to antagonize T cell activation in autoimmune conditions and to enhance transplant survival (10).
  Mice deleted for CTLA-4 show no abnormalities until after birth, but then develop lethal autoimmune reactions due to continued T cell activation and poor control by
  regulatory T cells, which constitutively express CTLA-4 in wild-type mice and humans (11-13).
• Source: HEK293 cells
• Species: Human
• Tag: Fc/Avi
• Predicted N Terminal: Ala37
• Form: Lyophilized from a 0.2 μm filtered solution in PBS with Trehalose.
• Bio-activity: Measured by its binding ability in a functional ELISA. When Recombinant Human CD80 Fc Chimera is immobilized at 0.5 µg/mL (100 µL/well), Biotinylated Recombinant Human CTLA4 Fc Chimera Avi-tag binds with an ED50 of 0.4-2.4 ng/mL.
• Molecular Mass: 53-61 kDa, under reducing conditions
• Protein length: Ala37-Phe162
• Endotoxin: <0.10 EU per 1 μg of the protein by the LAL method.
• Purity: >95%, by SDS-PAGE visualized with Silver Staining and quantitative densitometry by Coomassie® Blue Staining.
• Applications: Bioactivity
• Storage: Use a manual defrost freezer and avoid repeated freeze-thaw cycles.12 months from date of receipt, -20 to -70 °C as supplied.1 month, 2 to 8 °C under sterile conditions after reconstitution.3 months, -20 to -70 °C under sterile conditions after reconstitution.
• Reconstitution: Reconstitute at 500 μg/mL in PBS.

Gene Information

• Gene Name: CTLA4 cytotoxic T-lymphocyte-associated protein 4 [ Homo sapiens ]
• Official Symbol: CTLA4
• Synonyms: CTLA4; cytotoxic T-lymphocyte-associated protein 4; celiac disease 3 , CELIAC3; cytotoxic T-lymphocyte protein 4; CD; CD28; CD152; GSE; ICOS; CD152 isoform; celiac disease 3; cytotoxic T-lymphocyte antigen 4; cytotoxic T-lymphocyte-associated antigen 4; cytotoxic T-lymphocyte-associated serine esterase-4; cytotoxic T lymphocyte associated antigen 4 short spliced form; ligand and transmembrane spliced cytotoxic T lymphocyte associated antigen 4; GRD4; CTLA-4; IDDM12; CELIAC3
• Gene ID: 1493
• mRNA Refseq: NM_001037631
• Protein Refseq: NP_001032720
• UniProt ID: P16410