Properties of sulfatases in cultured skin fibroblasts of multiple sulfatase deficient patients

Various sulfatase activities were assayed in cultured skin fibroblasts from patients with multiple sulfatase deficiency (MSD). MSD cell lines displayed deficiencies of arylsulfatase A and iduronate sulfatase, but activities of arylsulfatase B, N‐acetylgalactosamine 6‐sulfate sulfatase and N‐acetylglucosamine 6‐sulfate sulfatase were within normal ranges, but not consistently. Arylsulfatase A, minor anionic arylsulfatase and N‐acetylgalactosamine 6‐sulfate sulfatase in MSD cell lines had similar Km, pH optima, inhibitory or activator sensitivity to that of normal skin fibroblasts. Arylsulfatase B in MSD cell lines also had properties similar to that of normal skin fibroblasts, except an abnormal heat stability. From our results, we conclude that properties of arylsulfatase A, minor anionic arylsulfatase and N‐acetylgalactosamine 6‐sulfate sulfatase in MSD fibroblasts were intact. On the other hand, arylsulfatase B in MSD might be a functionally abnormal enzyme.