HHLA2 protein, a key immune regulator, interacts with TMIGD2, providing crucial costimulation for T-cells during TCR-mediated activation. This interaction amplifies T-cell proliferation and cytokine production through an AKT-dependent signaling cascade, revealing HHLA2s role in enhancing T-cell responses and immune modulation. HHLA2 Protein, Human (HEK293, Fc) is the recombinant human-derived HHLA2 protein, expressed by HEK293 , with C-hFc labeled tag.