There are four principal objectives of the contract. The first is to prepare ceramidetrihexosidase in as high a degree of purity as possible in order to examine its effectiveness in replacement trials in patients with Fabry's disease. The second is to develop strategies to increase the half-life of the enzyme in blood to attempt to improve its clinical effectiveness since data obtained so far indicate that this enzyme probably exerts its effect on the accumulating lipid after endocytosis by leukocytes. The third is to develop methods to target the enzyme to specific cells in vascular endothelium and in the kidneys where the principal pathologic manifestations of Fabry's diseasee occur. The fourth is to produce antibodies to homogeneous enzyme for use as diagnostic probes and to facilitate the isolation of the human ceramidetrihexosidase gene.