Disclosed are various forms of an active, isolated .beta.-secretase enzyme
in purified and recombinant form. This enzyme is implicated in the
production of amyloid plaque components which accumulate in the brains of
individuals afflicted with Alzheimer's disease. Recombinant cells that
produce this enzyme either alone or in combination with some of its
natural substrates (.beta.-APPwt and .beta.-APPsw) are also disclosed, as
are antibodies directed to such proteins. These compositions are useful
for use in methods of selecting compounds that modulate .beta.-secretase.
Inhibitors of .beta.-secretase are implicated as therapeutics in the
treatment of neurodegenerative diseases, such as Alzheimer's disease.
