EXPRESSION OF CDNA-ENCODED HUMAN ACID ALPHA-GLUCOSIDASE IN MILK OF TRANSGENIC MICE

Enzyme replacement therapy is at present the option of choice for trea tment of lysosomal storage diseases. To explore the feasibility of lys osomal enzyme production in milk of transgenic animals, the human acid alpha-glucosidase cDNA was placed under control of the alpha(s1)-case in promoter and expressed in mice. The milk contained recombinant enzy me at a concentration up to 1.5 mu g/ml. Enzyme purified from milk of transgenic mice was internalized via the mannose 6-phosphate receptor and corrected enzyme deficiency in fibroblasts from patients. We concl ude that transgenically produced human acid alpha-glucosidase meets th e criteria for therapeutic application.