Recombinant Human IL23A&IL12B Heterodimer Protein (Active)

IL-23 drives Th17 differentiation and sustains chronic inflammatory responses, making precise quantification of its receptor engagement essential for modeling autoimmune pathology and evaluating therapeutic candidates. This heterodimeric protein demonstrates sub-nanomolar affinity (KD = 0.158 nM) to its cognate antibody in surface plasmon resonance assays and exhibits an EC50 of 0.73–0.86 ng/mL in functional ELISA, providing quantitative benchmarks for antibody development, epitope mapping, and competitive binding studies. Endotoxin levels below 1.0 EU/μg prevent LPS-driven artifacts in primary T cell differentiation assays, PBMC activation panels, and JAK/STAT signaling experiments where even trace contamination can confound cytokine-specific readouts. The protein spans residues 20–189 of IL-23A and 23–328 of IL-12B, preserving the mature heterodimer interface required for IL-23R engagement, and satisfies the purity criteria typical for use as an ELISA coating antigen, Western blot positive control, or immunogen in monoclonal antibody campaigns targeting IL-23-driven inflammatory pathways.