Recombinant Guinea pig Cytotoxic T-lymphocyte associated protein 4 (CTLA4), partial (Active)

CTLA-4 is a critical immune checkpoint receptor whose interaction with B7 ligands governs T-cell inhibitory signaling, making it a key target in comparative immunology studies using guinea pig models. This recombinant Cavia porcellus CTLA-4 covers the extracellular ligand-binding domain (aa 37–161) with a C-terminal 6xHis tag, and functional ELISA confirms robust B7-1 binding with an ED50 of 4.29 ng/ml, supporting use in receptor-ligand interaction assays, competitive inhibition studies, and blocking antibody screening. Yeast-derived expression provides eukaryotic post-translational processing while yielding sufficient conformational integrity for checkpoint binding experiments, as evidenced by the validated ligand engagement data. Endotoxin levels below 1.0 EU/μg and purity exceeding 90% by SDS-PAGE satisfy the criteria typical for sensitive functional assays, including affinity characterization by SPR or BLI and serving as a positive control in binding assays.