分子量:14.3 kDa

纯度:>95% as determined by SDS-PAGE.

内毒素:Less than 1.0 EU per μg of the Human CTLA-4, His Tag by the LAL method.

Buffer:PBS, pH7.4

生物活性:Measured by its binding ability in a functional ELISA. Immobilized Human CTLA-4, His Tag (Catalog # CT4-H5229) at 2 μg/mL ( 100 μl/well ) can bind Human B7-1, Fc Tag (Catalog # B71-H5259) with a linear range of 0.5-50 ng/mL.
Measured by its binding ability in a functional ELISA. Immobilized Human CTLA-4, His Tag (Catalog # CT4-H5229) at 2 μg/mL ( 100 μl/well ) can bind Human B7-2, Fc Tag (Catalog # CD6-H5257) with a linear range of 2-50 ng/mL.


产品特性:Human CTLA-4, His Tag is fused with a polyhistidine tag at the C-terminus, and has a calculated MW of 14.3 kDa. The predicted N-terminus is Ala 37 . The reducing (R) protein migrates as 23-25 kDa in SDS-PAGE  due to glycosylation.

产品背景:CTLA-4 (Cytotoxic T-Lymphocyte Antigen 4) is also known as CD152 (Cluster of differentiation 152), is a protein receptor that downregulates the immune system. CTLA4 is a member of the immunoglobulin superfamily, which is expressed on the surface of Helper T cells and transmits an inhibitory signal to T cells. The protein contains an extracellular V domain, a transmembrane domain, and a cytoplasmic tail. Alternate splice variants, encoding different isoforms. CTLA4 is similar to the T-cell co-stimulatory protein, CD28, and both molecules bind to CD80 and CD86, also called B7-1 and B7-2 respectively, on antigen-presenting cells. 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 be important to their function. T cell activation through the T cell receptor and CD28 leads to increased expression of CTLA-4, an inhibitory receptor for B7 molecules. Fusion proteins of CTLA4 and antibodies (CTLA4-Ig) have been used in clinical trials for rheumatoid arthritis.