A number of different classes of immunotherapeutic agents have been developed (see also table Some Immunotherapeutic Agents in Clinical Use): Monoclonal antibodies Fusion proteins Soluble cytokine receptors Recombinant cytokines Small-molecule mimetics Cellular therapies Table Monoclonal antibodies Monoclonal antibodies (mAbs) are manufactured in vitro to recognize specific targeted antigens (Ags); they are used to treat solid and hematopoietic tumors, inflammatory disorders, and infections.