At Naples Tigem adeno-associated virus used against Mucopolysaccharidosis type 6 to deliver the enzyme deficient in the liver directly without immunological rejection.

genetic defect

Treatment approaches: once again have to write a virus allies hope to treat rare genetic disorders. Research conducted by Alberto Auricchio, Telethon Institute of Genetics researcher and medicine (Tigem) of Naples, published in Molecular Therapy, has shown efficacy in animal models and stability over time of gene therapy for mucopolysaccharidosis type 6, metabolic disease of genetic origin. Thus shortening the time to transfer the therapy in humans.

Also known as Maroteaux-Lamy disease, the Mucopolysaccharidosis Type 6 is a genetic disease caused by a defect in the gene that contains the information for an enzyme responsible for the disposal of large molecules, the mucopolysaccharides that accumulate in cells as well. It is very rare – in Italy are only 11 known cases – and usually begins in childhood: over time the accumulation of non-disposed leads to skeletal deformities, vision problems and heart failure due to valve dell’inspessimento of the heart. Unlike other mucopolysaccharidoses, this form does not affect the central nervous system, so people with no mental retardation.

For several years is available enzyme replacement therapy, which involves the infusion of the enzyme is missing once a week: however, this treatment is not entirely conclusive, because it’s hard to get to the bones, organs from poor circulation in blood vessels which can carry. To further improve the quality of life of these patients, researchers have been working for years to Tigem another therapeutic approach, gene therapy, which may be more effective in bone and above all less invasive because it would require a single dose. This therapy is to deliver the correct copy of the defective gene in these patients by a virus, be amended because it is not malicious but still capable of carrying genetic material into target cells.


Researchers have used Tigem of specific viruses, known as “adeno-associated”, which were administered directly into the liver of the animal, that is where the enzyme is normally produced. For the first time, researchers were able to make Telethon therapy without causing any immunological rejection response against the exogenous gene. Scientists have observed a year later, not only an increase of waste disposal cell, but also a lengthening of the long bones (femur and humerus), dell’ispessimento reduction of cardiac valves and a marked improvement in spontaneous mobility.

“Our work shows that the strategy we developed for the 6 MPS works effectively in a disease model,” said Auriemma. “Preliminary results of a British group suggest that a strategy very similar to ours is effective in patients with another hereditary disease, hemophilia. That bodes well for the future development of gene therapy for mucopolysaccharidosis 6, to which we are actively working with support from the Telethon Foundation. “