Abstract: The invention provides methods for efficient recombinant expression, refolding, and purification of Beta-site APP cleaving enzyme (BACE) polypeptides. In various aspects, the method includes the steps of expressing a recombinant construct in bacteria, dissolving inclusion bodies with a denaturant at high pH in the presence of a reducing agent, diluting the solubilized BACE polypeptide in an aqueous solution at a temperature of about 1° C. to 15° C., and incubating the diluted sample at a temperature of about 4° C. to 15° C. until the recombinant BACE polypeptide folds into an active enzyme.

Abstract: The present invention provides isolated human heparanase polypeptides, and the isolated polynucleotide molecules that encode them, as well as vectors and host cells comprising such polynucleotide molecules. The invention also provides a method for the identification of an agent that alters heparanase activity.