Human CTLA-4 Recombinant Protein

Catalog Number:: RP1844H
Application:: Cell Culture, Control, ELISA, ELISpot Control, Western Blot Control
100% Homology:: Gorilla gorilla gorilla (western lowland gorilla), Homo sapiens (human), Pan paniscus (pygmy chimpanzee), Pan troglodytes (chimpanzee)

Product Description

Human CTLA-4 (Cytotoxic T-Lymphocyte-Associated Protein 4) (catalog RP1844H) is a yeast-derived immune checkpoint protein supplied lyophilized without carrier protein in 10% trehalose; it has no affinity tags and is naturally endotoxin-free, and should be reconstituted in sterile PBS that contains at least 0.1% carrier protein. The protein is ~13.5 kDa, 126 amino acids long (full sequence provided), and >98% pure by SDS-PAGE, with 100% amino-acid homology to human, pygmy chimpanzee, chimpanzee, and western lowland gorilla. Store at -20°C (stable up to twelve months from date of receipt; working aliquots with carrier protein stable ~3 months) and avoid repeated freeze/thaw cycles. Product origin is the USA. It is commonly used to study CTLA-4 signaling and immune regulation (including roles in T-cell inhibition, immune checkpoint pathways, and modulation of immune responses); typical experimental uses include cell-culture stimulation and receptor-binding assays, immune checkpoint and signaling studies, ELISA and neutralization assays, flow-cytometry and Western blot controls, and antibody generation/validation. Kingfisher Biotech products are supplied for research applications and are not intended for medicinal, diagnostic, or therapeutic use.

Properties/Specifications

Amino Acid Sequence	KAMHVAQPAV VLASSRGIAS FVCEYASPGK ATEVRVTVLR QADSQVTEVC AATYMMGNEL TFLDDSICTG TSSGNQVNLT IQGLRAMDTG LYICKVELMY PPPYYLGIGN GTQIYVIDPE PCPDSD (126)
Endotoxin	Naturally endotoxin-free
Form	Lyophilized
Storage Conditions	-20°C
Molecular Weight	13.5 kDa
Purity	>98% as visualized by SDS-PAGE analysis.
Affinity Tag	None
aminoAcids	126
Carrier Protein	None
Expression System	Yeast
Form	Lyophilized
Country Of Origin	USA

Human CTLA-4 (Cytotoxic T-Lymphocyte–Associated Protein 4, also known as CD152) is an immune checkpoint receptor belonging to the immunoglobulin superfamily that plays a critical role in the negative regulation of T-cell activation and maintenance of immune tolerance. CTLA-4 is primarily expressed on activated CD4⁺ and CD8⁺ T lymphocytes and constitutively on regulatory T cells (Tregs) following antigen stimulation. It binds to the costimulatory ligands CD80 (B7-1) and CD86 (B7-2) on antigen-presenting cells such as dendritic cells, macrophages, and B cells, competing with the activating receptor CD28 for these ligands. Engagement of CTLA-4 transmits inhibitory signals that reduce T-cell proliferation, cytokine production, and immune activation, thereby maintaining immune homeostasis and preventing excessive or autoimmune immune responses. Dysregulation of CTLA-4 signaling has been associated with autoimmune diseases, chronic inflammatory disorders, and cancer immune evasion. CTLA-4 is also a major target in cancer immunotherapy, where checkpoint inhibitor antibodies such as ipilimumab block CTLA-4 signaling to enhance T-cell–mediated antitumor immunity, making CTLA-4 a central focus in immunology, oncology, and therapeutic development.