In a major advancement towards an effective treatment of Alzheimer’s disease, Swiss scientists have developed an implantable capsule that can turn the patient’s immune system against the disease.
One of the hypothesised causes of Alzheimer’s is the over-accumulation of the protein amyloid beta (Abeta) in different areas of the brain.
This results in the deposition of aggregated protein plaques, which are toxic to neurons. One of the most promising ways to fight the plaques is to “tag” the Abeta proteins with antibodies that signal the patient’s own immune system to attack and clear them.
To be most effective, this treatment has to be given as early as possible, before the first signs of cognitive decline. But this requires repeated vaccine injections, which can cause side effects.
The scientists at Swiss Federal Institute of Technology in Lausanne (EPFL) have now solved the problem with an implant that can deliver a steady and safe flow of antibodies to the patient’s brain to clear Abeta proteins.
The study was published in the journal Brain.
The lab of Patrick Aebischer at EPFL developed a bioactive capsule containing cells that have been genetically engineered to produce antibodies against Abeta.
The capsule is implanted in the tissue under the skin, and over time the cells produce and release a steady flow of antibodies into the bloodstream, from where they cross over into the brain to target the Abeta plaques.
Before going into capsule, the cells are first genetically engineered to produce antibodies that specifically recognise and target Abeta, the researchers explained.
The researchers tested the device on mice with great success. The mice, a genetic line that is commonly used to simulate Alzheimer’s disease showed dramatic reduction of Abeta plaque load, the study said.
The constant flow of antibodies produced by the capsule over a course of 39 weeks prevented the formation of Abeta plaques in the brain.
The treatment also reduced the phosphorylation of the protein tau, another sign of Alzheimer’s observed in these mice, the researchers said.