A humanized agonistic monoclonal antibody targeting the cell surface antigen CD27, with potential immunostimulatory and antineoplastic activities. Upon administration, boserolimab targets and binds to CD27 on a variety of immune cell types, including most T-lymphocytes. This induces CD27-dependent signaling pathways and enhances T-cell-mediated responses, including the expansion of antigen-activated T-cells and the cytotoxic T-lymphocyte (CTL)-mediated immune response against tumor cells. CD27, a co-stimulatory molecule and member of the tumor necrosis factor receptor superfamily (TNFRSF), is expressed on T-lymphocytes, memory B-cells and natural killer (NK) cells. It plays an important role in NK cell-mediated cytolytic activity and T- and B-lymphocyte proliferation and activation. It is overexpressed in certain tumor cell types.