Demonstration of altered acidic hydrolases in fibroblasts from patients with mucolipidosis II by lectin titration.

Decreased binding by the lectins concanavalin A and wheat-germ agglutinin was found for a number of acidic hydrolases from skin fibroblasts of three unrelated patients with mucolipidosis II. This decreased binding as compared with normal controls was demonstrated by titration of hydrolase activities with increasing amounts of immobilized lectins. Neuraminidase treatment slightly improved the binding of enzymes from mucolipidosis-II patients, in contrast with the diminished binding found or hydrolases from control cell lines. The abnormality in binding by lectins of hydrolases of mucolipidosis-II patients was observed for enzymes with various degrees of intracellular deficiency as well as for enzymes with normal intracellular activities. These findings suggest a generalized alteration of fibroblast acidic hydrolase molecules in mucolipidosis II.