A NEW MODEL OF ACTIVE SPECIFIC IMMUNOTHERAPY USING INTERLEUKIN-1 AND SONICATED TUMOR SUPERNATANT IN MURINE TUMOR SYSTEM

The possibility of active specific immunotherapy using interleukin-l ( IL-1) plus sonicated tumor supernatant (SS) was examined in a murine t umor model. The growth of intraperitoneally or subcutaneously inoculat ed plasmacytoma MOPC104E, which is syngeneic to BALB/c mice, was signi ficantly suppressed by intraperitoneal pretreatment with IL-l and SS f rom MOPC104E cells (MOPC-SS), on days 10, 7, and 4 before tumor inocul ation. Pretreatment with IL-1 plus MOPC-SS or MethA-SS (SS from MethA cells) suppressed the growth of subcutaneous tumor of only the corresp onding tumor cells, indicating the development of tumor-specific immun ity in vivo. The splenic cells of immunized mice with IL-1 and MOPC-SS showed tumor neutralizing activity. However, their tumor neutralizing activity was abrogated when they were treated in vitro with anti-Thy1 .2 or anti-L3T4 plus complement. Moreover, when combined with indometh acin per oral, IL-1 plus MOPC-SS significantly suppressed the growth o f established subcutaneous tumor and prolonged survival of postoperati ve mice. These results suggest that this new type of active specific i mmunotherapy could be a useful method for cancer immunotherapy, especi ally when combined with oral indomethacin. (C) 1996 Wiley-Liss, Inc.