Abstract: This invention relates to processes and compositions for the immunotherapeutic treatment of cancer and non-malignant tumors. More particularly, this invention relates to processes and compositions for enhancing the body's immune response by increasing the cytotoxic activity of cells which mediate antibody dependent cellular cytotoxicity. Cells which are characterized by increased cytotoxic activity, as a result of the process of this invention, are useful in methods and compositions for the treatment of various types of cancer and non-malignant tumors.