I-cell disease: intracellular desialylation of lysosomal enzymes using an influenza virus vector.

It has been proposed that I-cell disease results from a primary deficiency of acid neuraminidase activity. Infection by influenza virus of fibroblasts from a patient with I-cell disease resulted in the production of abundant intracellular alpha2-3 neuraminidase activity. Despite electrophoretic evidence of desialylation of intracellular and fibroblast-secreted arylsulfatase (EC 3.1.6.1) and beta-hexosaminidase (EC 3.2.1.30) from the infected cells, there was no consequent alteration of the abnormal distribution of beta-hexosaminidase activity between the intracellular spaces characteristic of I-cell disease. This suggests that deficiency of alpha2,3 neuraminidase activity is not the primary biochemical defect in I-cell disease.