METABOLIC CORRECTION OF FUCOSIDOSIS LYMPHOID-CELLS BY GALAPTIN-ALPHA-L-FUCOSIDASE CONJUGATES

To determine if isolated galaptin, an endogenous galactoside-binding lectin, could serve as a transport vehicle of therapeutic agents to cells, galaptin and α-L-fucosidase were coupled using glutaraldehyde. The conjugates were incubated with α-L-fucosidase-deficient, EBV-immortalized lymphoid cells from a fucosidosis patient. Conjugates were effectively bound and internalized by the cells in a lactose inhibitable manner. Internalization of conjugate resulted in the reduced accumulation of α-L-fucosyl-N-acetylglucosaminylasparagine, a glycopeptide that accumulates in cells of fucosidosis patients, to levels found in lymphoid cells from a healthy individual. Thus, galaptin-α-L-fucosidase conjugates may be useful for enzyme replacement therapy of fucosidosis. The concept of using galaptin as a transport vehicle may be applied to the delivery of other compounds to cells bearing galaptin receptors. © 1990 Academic Press, Inc.