Enzyme replacement therapy in a murine model of mucopolysaccharidosis type IIIA / by Briony Lee Gliddon.

Abstract

Mucopolysaccharideosis type IIIA (MPS IIIA, Sanfilippo A syndrome) is an autosomal recessive lysosomal storage disease, with a prevalence in Australia of 1 in 114,000. MPS IIIA is caused by a deficiency of the lysosomal enzyme sulphamidase which is needed together with other exohydrolases and a N-acetyltransferase to break down the glycosaminoglycan heparan sulphate to sulphate and monosaccharides. Patients are characterised by severe central nervous systems degeneration together with mild somatic involvement; this disproportionate correlation is unique amongst the mucopolysaccharidoses. Features include severe behavioural disturbances, such as hyperactivity and aggressiveness, coarse hair and mild hepatosplenomegaly. Death is usually in the mid- to late-teenage years. Enzyme replacement therapy by intravenous administration of recombinant human NS (rhNS) has been proposed as a potential therapy for MPS IIIA. This thesis suggests that rhNS, entering the brain in the first few weeks of life, is able to retard the behaviour and learning difficulties in MPS IIIA mice.