This anti-BTLA antibody is a purified recombinant human monoclonal antibody which recognizes the human BTLA protein. BTLA (B- and T-lymphocyte attenuator) belongs to the CD28 immunoglobulin superfamily (IgSF) and is an immune-regulatory receptor that binds to HVEM (Herpesvirus entry mediator, also known as TNFRSF14, Tumor necrosis factor receptor superfamily member 14). This antibody has been tested for specific binding to purified human BTLA protein and neutralizes the interaction between BTLA and HVEM.