CTLA-4 protein acts as a primary inhibitory receptor, playing a major role in regulating T-cell responses. Its strong affinity for CD80 and CD86 receptors allows CTLA-4 to effectively suppress T-cell activation and maintain immune balance. This interplay is crucial for fine-tuning T-cell-mediated immunity. CTLA-4 Protein, Rhesus Macaque (HEK293, His) is the recombinant Rhesus Macaque-derived CTLA-4 protein, expressed by HEK293 , with C-His labeled tag.