Presence of arylsulfatase A (ARS A) in multiple sulfatase deficiency disorder fibroblasts

Multiple deficiency disorder fibroblasts cultured in MEM-CO ₂ showed deficiencies of arylsulfatase A (ARS A) comparable to the deficiency in metachromatic leukodystrophy fibroblasts. However, the MSDD fibroblasts cultured in MEM-HEPES contained near normal levels of ARS A. Moreover, the enzyme from the latter fibroblasts was indistinguishable from ARS A of control fibroblasts on DEAE-cellulose chromatography, ratio of activity with several substrates, thermal inactivation, sensitivity to inhibitors, and precipitation by antiserum to human ARS A. These data support the conclusion that the ARS A genome is intact in MSDD fibroblasts and, by extension, in MSDD patients. Other sulfatases were present at levels ranging from mildly deficient to near normal but never as low as seen in the corresponding specific sulfatase deficient disorders.