Combination Immunotherapy for Cancer:Synergistic Antitumor Interactions of Interleukin-2, Alfa Interferon, and Tumor-Infiltrating Lymphocytes

Abstract

Attempts have been made to design optimal strategies for the immunotherapy of established tumors. In micebearing pulmonary metastases from sarcomas, a substantial therapeutic synergy was seen when bothinterleukin-2(IL-2) and alfa interferon(α-IFN) were administered compared with the effect of either agentgiven alone. This synergy was dependent on Lyt-2⁺T cells, since therapeutic effects were abrogated in Lyt-2 depleted mice. The αIFN and IL-2 combination was also synergistic with tumor-infiltrating lymphocytes inmediating the reduction of established lung metastases. These experiments demonstrate that combination immunotherapy can result in substantial reduction of established metastatic deposits and provide a rationale for the application of this treatment to patients with advanced cancer. [J National Cancer Inst 1988;80:1393–1397]