TARGETING PSEUDOMONAS EXOTOXIN TO HEMATOLOGIC MALIGNANCIES

Malignant cells of hematopoietic origin often express a variety of different growth factor receptors and antigens on their surface, at levels much higher than normal cells. These malignant cells can be selectively Pseudomonas exotoxin (PE) derivatives interleukins 2, 4 and 6, and by FV fragments of monoclonal antibodies to interleukin 2 receptor (IL2R) subunits, CD22 and other antigens present on these cells. Anti-Tac(Fv)-PE38, a single-chain recombinant immunotoxin which targets cells bearing the IL2R alpha, is furthest along in preclinical development and is being prepared for clinical testing in patients with IL2R alpha-positive leukemia, lymphoma and Hodgkin's disease. (C) Academic Press Ltd