Alzheimer's may be prevented by antibody-releasing implant
A newimplantable capsule may provide a novel way of tackling Alzheimer'sdisease, preventing the buildup of harmful protein plaques in thebrain. The small device, developed by researchers at the SwissFederal Institute of Technology in Lausanne (EPFL), has beensuccessfully tested on laboratory mice.
The capsule tackles the disease bytargeting Abeta proteins, also known as amyloid beta, which build upand form toxic plaques in the brain. One way of dealing with theplaques is to "tag" the harmful protein cells, instructing theimmune system to attack them and, ideally, preventing the plaquesfrom building up in the first place.
Achieving that goal can be difficult,and such treatment currently requires regular vaccine injections,which have been known to cause undesirable side effects. The EPFLresearchers' method addresses those issues, providing a singletreatment that's able to work over extended periods of time, andwithout side effects.
The idea is fairly simple – ratherthan repeatedly injecting antibodies into the patient's system, theresearchers worked on a method that uses a single capsule which isimplanted under the skin to provide a steady flow of treatment.
The tiny capsule, known as amacroencapsulation device, consists of two permeable membranesconnected via a polypropylene frame. Measuring 27 mm (1 in) in length and 1.2 mm (0.05 in) thick,the capsule is biocompatible and contains hydrogel, which facilitatescell growth. The cells that reside with the device are geneticallyengineered to produce antibodies that recognize and target theprotein, instructing the immune system to destroy it.
The membranes of the capsule also play animportant role, shielding the cells inside from being attacked by thehost's immune system, while allowing them to interact withsurrounding tissue to get the required nutrients. As the cells areprotected from the patient's immune system, a single donor canprovide cells for multiple patients.
The capsule was tested with laboratorymice over a period of 39 weeks. The results were hugely positive,with the sustained antibody production preventing the formation ofamyloid beta plaques in the brain.
The findings are very promising, andcould signal a new path to Alzheimer's prevention. It is however worth notingthat the research is still in the early stages, and that human trialswould need to be conducted before its effectiveness could beconfirmed and widespread use could be considered.
The findings of the research arepublished online in the journal Brain.