monoclonal antibody, isolated human, isolated monoclonal antibody, composition, immunoconjugate, bispecific molecule, isolated nucleic acid molecule, expression vector, host cell, transgenic mouse, hybridoma prepared from mouse, method of modulating an immune response in a subject, Method of inhibiting tumor cell growth in a subject, Method of treating an infectious disease in a subject, Method of enhancing immune response to an antigen in a subject, and Method for preparing an anti-beta antibody