Human CTLA4 Protein (C-His-Avi) was biotinylated in vitro using BirA ligase. SDS-PAGE analysis under reducing (P+) and non-reducing (P−) conditions shows the protein has a purity greater than 95%. A gel shift assay using co-incubation with streptavidin indicates that the biotinylation efficiency of the CTLA4 protein exceeds 90%.
Human B7-1 with Fc tag is coated at 2ug/mL (200ng/well). Biotinylated human CTLA4 (C-His-Avi) can bind B7-1 in dose-dependent manner with the ED50 of 3-10 ng/mL
Cat #
Size
Price
Quantity
807803
25 ug
$245
807804
100 ug
$595
Product Details
Application
ELISA, BLI
Format
Liquid, Biotinylated
Expression Host
CHO
Target Name
CTLA4, CD152
Species
Human
Sources
Recombinant Human CTLA4 Protein (Ala37-Phe162) with C-terminus His-Avi-tag is expressed in CHO cell. This protein was site-specifically labeled with Biotin by BirA ligase.
accession number
P16410
Molecular Weight
The protein has a predicted molecular weight of 17.1 kDa. Under DTT-reducing conditions, it migrates at approximately 20 kDa on SDS-PAGE.
Affinity Tag
C-His-Avi
Purity
>95% based on SDS-PAGE under reducing condition
Formulation
1xPBS buffer, pH7.4, 0.22 µm filtered
Endotoxin level
Not tested
Protein Concentration
25µg size is bottled at 0.2mg/mL concentration. 100 µg size is supplied at a lot-specific concentration.
Storage and Handling
Briefly centrifuge the vial upon receipt. An unopened vial can be stored at 4°C for up to 2 weeks, or at -20°C or below for up to six months. The protein may be further diluted to 0.1 mg/mL using 0.22 µm-filtered PBS buffer (pH 7.4). For long-term storage, the diluted stock solution should be aliquoted and stored at ≤ –70°C to minimize freeze-thaw cycles. If additional dilution is required, carrier proteins such as FBS or BSA should be added to maintain protein stability.
Background Information
Cytotoxic T-lymphocyte-associated protein 4 (CTLA-4), also known as CD152, is an immune checkpoint receptor found on T cells. It shares 30% homology with CD28 and binds to the same ligands, B7.1/CD80 and B7.2/CD86, but with higher affinity. After T-cell activation, increased CTLA-4 expression leads to immune suppression by binding to CD80/CD86, inhibiting further T-cell activation through a process called trans-endocytosis.CTLA-4 is crucial for immune regulation and tolerance, especially on regulatory T cells (Tregs). Soluble CTLA-4 (sCTLA-4) further enhances Treg function and is linked to autoimmune diseases like type 1 diabetes. Additionally, CTLA-4 plays a role in chronic lymphocytic leukemia (CLL) progression.Due to its immune-modulatory role, CTLA-4 is targeted in cancer therapy. Ipilimumab, a monoclonal antibody that blocks CTLA-4, is approved for melanoma and is being explored for other cancers.