Immunotoxins: A new approach to cancer therapy

Conjugates of tumor-reactive antibody and toxins (immunotoxins) have been used to eradicate tumor cells in vitro and in vivo. Such immunotoxins are highly effective in killing murine leukemic cells in infiltrated bone marrow and should be useful in the bone marrow rescue approach for the treatment of cancer. Similar immunotoxins injected parentally can help to induce prolonged remissions in leukemic mice, and antigen-containing immunotoxins can induce immunologic unresponsiveness in vitro in normal murine splenocytes. Thus, long-range goals for the parental use of immunotoxins include the killing of cancer cells in vivo and the modulation of the immune response for therapeutic purposes.