SUCCESSFUL THERAPY TO A PROGRESSIVE TUMOR USING MONOCLONAL-ANTIBODIESTO T-CELL REGULATORY MOLECULES AND INTERLEUKIN-2

Weekly injections of monoclonal antibodies (mAb) to T-cell regulatory molecules, into animals challenged with a progressively growing epithe lial cell tumor 3152-PRO, decreased tumor incidence and caused signifi cantly slower tumor growth, compared with animals given identical trea tments of control rat mAb. Some of the mAb showed significant synergy with rIL-2 in the successful therapeutic treatment of 3152-PRO. Furthe rmore, spleen cells from treated mice generated strong tumor-specific cytotoxic activity. The successful elimination of progressively growin g 3152-PRO tumor rendered animals specifically resistant to a secondar y challenge of 3152-PRO tumor cells, but not to 2237-PRO or 3256-PRO, two other, noncrossreactive tumors.