Sulfatase B activity was deficient in tissues from patients with type VI mucopolysaccharidosis (Maroteaux-Lamy syndrome; MPS VI). Liver, kidney, spleen, brain, and cultured fibroblasts all showed deficient activity. The sulfatase B deficiency was most evident in assays of pellet fractions. Sulfatase B activity was not reduced in the other mucopolysaccharidoses tested (types I, II, and III). The activities of control lysosomal enzymes (sulfatase A and acid phosphatase) were not reduced in MPS VI tissues.
The evidence suggests that a sulfatase B deficiency may underlie the biochemical abnormalities responsible for the MaroteauxLamy syndrome. The findings also lend credence to the view that sulfatase B normally plays a catabolic role as an O-sulfatase in the pathways of sulfated mucopolysaccharide metabolism. The possibility that oligosaccharide chondroitin sulfate B (dermatan sulfate) is a substrate for sulfatase B remains to be critically tested.