Researchers Can Alzheimer's Disease Be Transmitted to Others?

Transferability of the pathological amyloid beta proteins confirmed

Alzheimer's is a dreaded neurodegenerative disease that affects mostly the elderly and has dramatically increased in recent decades. As early as 2015, researchers from Univesity College London had suggested that the disease could be transmissible via the misfolded amyloid proteins. In laboratory experiments on mice, they now confirmed the suspicion.

Alzheimer's disease is considered a non-communicable disease. It threatens no infection in the ordinary contact with stakeholders, emphasize the British scientists. However, a 2015 study has already shown that the pathological amyloid beta proteins may be transmitted from human to human as part of medical treatment. In their current study, researchers at University College London have confirmed this. Their results were published in the journal "Nature".

Transmission in hormone therapy?

"Our previous study found that some individuals who developed CJD many years after treatment with pituitary growth hormone also had deposits in the brain of an abnormal protein that is characteristic of Alzheimer's disease," says the lead author the study, Professor John Collinge from the starting point of the current investigation. The reason suspected the researchers in the transmission of the misfolded protein structures with the growth hormones. In their current research, they have now shown that the pituitary growth hormones actually contain the corresponding amyloid beta proteins.

Contaminated growth hormone contamination

"The findings support the hypothesis that amyloid-beta was inadvertently transmitted to patients through this long-interrupted medical treatment," the researchers said in a press release. Human growth hormone - made from human tissue prior to 1985 - actually contained Alzheimer's disease amyloid beta protein deposits. In the next step, the research team examined whether the growth hormone protein contaminants also lead to the development of the amyloid deposits typical of Alzheimer's disease.

Experiments on mice

The researchers injected genetically modified mice with the contaminated growth hormone into the brain and found that after less than 12 months, "clear seeding of the amyloid pathology in their brains" already took place. The same was observed in mice injected with tissue from patients with typical Alzheimer's disease. However, mice injected with synthetic growth hormone or normal brain tissue did not show such patterns.

Amyloid beta pathology is transferable

"We have now put forward experimental evidence to support our hypothesis that amyloid-beta pathology can be transferred from contaminated materials to humans," said Professor Collinge. Whether medical or surgical interventions can cause or transmit Alzheimer's disease in humans is currently not clear. "It will be important to review the risks of transmitting amyloid pathology in other medical procedures that are still used today - including brain surgery tools," said the expert.

Threatens infection in contact with Alzheimer's patients

The current study provides new insights into the molecular mechanisms underlying the role of amyloid in Alzheimer's disease, but the researchers explicitly emphasized that there is currently no evidence of Alzheimer's between humans. The study gives no indication that you can get Alzheimer's disease through contact with a sick person. (Fp)