A human agonistic monoclonal antibody (MoAb) specific for CD27, with potential immunostimulating and antineoplastic activity. Upon administration of CDX-1127, this MoAb binds to CD27 and may potentiate the immune response by increasing the cytotoxic T-lymphocyte (CTL) response against CD27-expressing tumor cells. This may lead to growth inhibition of CD27-expressing tumor cells. In addition, this agent may increase the proliferation and activation of antigen-specific T lymphocytes upon co-administration of TAA-containing vaccines, such as dendritic cell vaccines. CD27, a co-stimulatory molecule and member of the tumor necrosis factor family overexpressed in certain tumor cell types, is constitutively expressed on mature T-lymphocytes, memory B cells and natural killer cells and plays an important role in NK cell mediated cytolytic activity and T and B lymphocyte proliferation and activation.