Recombinant human CTLA4 protein aa 1-161 was produced in mammalian cells with C-terminal His-DYK tag. The theoretical molecular weight of recombinant CTLA4 is 15.6 kDa. Purified CTLA4 protein is below the position of 26 kDa on SDS-PAGE gel under reduced condition.
CTLA4 protein is purified by proprietary chromatographic techniques. 

Entrez Gene summary for CTLA4:

This gene is a member of the immunoglobulin superfamily and encodes a protein which transmits an inhibitory signal to T cells. The protein contains a V domain, a transmembrane domain, and a cytoplasmic tail. Alternate transcriptional splice variants, encoding different isoforms, have been characterized. The membrane-bound isoform functions as a homodimer interconnected by a disulfide bond, while the soluble isoform functions as a monomer. Mutations in this gene have been associated with insulin-dependent diabetes mellitus, Graves disease, Hashimoto thyroiditis, celiac disease, systemic lupus erythematosus, thyroid-associated orbitopathy, and other autoimmune diseases.

UniProtKB/Swiss-Prot: P16410 (CTLA4_HUMAN)

Function: Inhibitory receptor acting as a major negative regulator of T-cell responses. The affinity of CTLA4 for its natural B7 family ligands, CD80 and CD86, is considerably stronger than the affinity of their cognate stimulatory coreceptor CD28.