A biomarker-based blood test could boost blood donations, free from the worry of passing along the human form of mad cow disease, variant Creutzfeldt–Jakob disease (vCJD).
Mad cow disease (bovine spongiform encephalopathy or BSE) is a neurodegenerative disorder and is transmitted by a prion, a misfolded form of a protein that infects and "corrupts" the healthy, properly folded versions of the protein. The U.K. had an outbreak of BSE in the 1980s, and as a result of eating infected meat, about 200 people died. Because of concerns about infection, a number of countries, including Australia, restrict blood donations from people who have stayed in the U.K. during the 1980s and '90s, or who have received a blood transfusion.
Many cells form and release tiny bubbles of cell membrane (vesicles) from their surfaces. These exosomes travel around the bloodstream and contain microRNA (miRNA), small pieces of non-coding RNA. Researchers from the University of Melbourne in Australia have found that Infection with the prion changes the miRNA signature, and believe that sequencing the signature could lead to a blood test for infection and exposure, increasing the number of people who could donate and increasing critical blood stocks. The research was published in Nucleic Acids Research.
According to Shayne Bellingham, the breakthrough might also help detect other human neurodegenerative diseases, such as Alzheimer's and Parkinson's disease: "This is an exciting new field where we can test for conditions in the brain and throughout the body, without being invasive," he said.