Cleavage of the amyloid precursor protein (APP) within the amyloid-beta (Ab) sequence by the a-secretase prevents the formation of toxic Abpep-tides. It has been shown that the disintegrin-metalloproteinases ADAM10 and TACE (ADAM17) act asa-secretases and stimulate the generation of a soluble neuroprotective fragment of APP, APPsa.