Lysosomal storage diseases – the abstract term conceals thousands of fates. The symptoms are severe, the prognosis extremely poor: most patients die in childhood.
The Diseases
Lysosomal storage disease is a collective term for around 70 metabolic diseases – for example Gaucher’s disease, Hunter’s disease or metachromatic leukodystrophy. Most of these diseases cause severe damage to the nervous system and other organs. Around one in every 8,000 newborns is affected. These severe disorders are caused by a lack of enzymes in the so-called lysosome. Lysosomes perform a kind of waste disposal function in our body by using enzymes to break down and recycle our ‘cellular waste’ – for example old proteins. If the enzymes are missing, the superfluous components are stored.
The Research
Many of the enzymes that are missing in lysosomal storage disease can be produced artificially and can be injected into patients’ veins. However, it is difficult to transfer them from the blood to the defective brain cells. This is due to the blood-brain barrier, which protects the brain from harmful substances. The artificial enzymes have difficulty getting past it. But how could it work? Prof Dr Volkmar Gieselmann from the University of Bonn and Prof Dr Hans-Joachim Galla from the University of Münster have been working on this for years. They used the award money from the Eva Luise Köhler Research Award to advance their research into the blood-brain barrier. Their goal: to gain an even better understanding of the transport pathways and to modify enzymes so that they can cross the blood-brain barrier after all. The researchers focussed on the enzyme arylsulfatase A, which is missing in metachromatic leukodystrophy.
The Future
Over the past few years of research, the scientists have been able to produce a specifically modified arylsulphatase A: this artificial ‘turbo enzyme’ not only reaches the brain better, it is also more active and more stable. In animal experiments, this enzyme showed a significantly improved effect. There is now a patent on this new therapy option for metachromatic leukodystrophy. The next step is to make it available to patients. This requires co-operation with the industry. Prof Dr Volkmar Gieselmann: ‘We are in contact with biotech companies and hope to make rapid progress so that we can finally save patients from their difficult fate.’
