Israeli scientists are harnessing the “destructive” qualities of allergy-causing cells, as part of a bold attempt to pioneer a new immunotherapy for fighting cancer. A research team from Tel Aviv University has found that eosinophils, white blood cells that induce allergies, significantly reduce the growth of human tumors in vitro, and mouse tumors in the body. Nine days after mice were injected with eosinophils, the overall size of tumors per mouse averaged half that of mice who weren’t injected.