Non-viral transfer approaches for the gene therapy of mucopolysaccharidosis type II (Hunter syndrome).
OBJECTIVE
Hunter syndrome is a rare X-linked lysosomal storage disorder caused by the deficiency of the housekeeping enzyme iduronate-2-sulphatase (IDS). Deficiency of IDS causes accumulation of undegraded dermatan and heparan-sulphate in various tissues and organs. Approaches have been proposed for the symptomatic therapy of the disease, including bone marrow transplantation and, very recently, enzyme replacement. To date, gene therapy strategies have considered mainly retroviral and adenoviral transduction of the correct cDNA. In this paper, two non-viral somatic gene therapy approaches are proposed: encapsulated heterologous cells and muscle electro-gene transfer (EGT).


METHODS
Hunter primary fibroblasts were co-cultured with either cell clones over-expressing the lacking enzyme or with the same incorporated in alginate microcapsules. For EGT, plasmid vector was injected into mouse quadriceps muscle, which was then immediately electro-stimulated.


RESULTS
Co-culturing Hunter primary fibroblasts with cells over-expressing IDS resulted in a three- to fourfold increase in fibroblast enzyme activity with respect to control cells. Fibroblast IDS activity was also increased after co-culture with encapsulated cells. EGT was able to transduce genes in mouse muscle, resulting in at least a tenfold increase in IDS activity 1-5 weeks after treatment.


CONCLUSIONS
Although preliminary, results from encapsulated heterologous cell clones and muscle EGT encourage further evaluations for possible application to gene therapy for Hunter syndrome.
Tomanin
R
R
Centre for Rare Diseases, Department of Pediatrics, University of Padova, Italy.
Friso
A
A
Alba
S
S
Piller Puicher
E
E
Mennuni
C
C
La Monica
N
N
Hortelano
G
G
Zacchello
F
F
Scarpa
M
M
D000818:Animals; D002999:Clone Cells / Q000637:transplantation; D018920:Coculture Techniques; D004195:Disease Models, Animal; D005347:Fibroblasts / Q000637:transplantation; D018014:Gene Transfer Techniques; D015316:Genetic Therapy; D005822:Genetic Vectors / Q000627:therapeutic use; D051379:Mice; D008810:Mice, Inbred C57BL; D016532:Mucopolysaccharidosis II / Q000235:genetics* / Q000628:therapy*; D032446:Myoblasts / Q000637:transplantation; D014183:Transplantation, Heterologous