Proteins that normally reside inside cell nuclei have never been found in the blood, until now. A new blood test developed at the Johns Hopkins University by Shih-Chin Wang and Chih-Ping Mao—graduate students in Jie Xiao’s lab in the Department of Biophysics and Chien-Fu Hung’s lab in the Department of Pathology—can identify individual molecules in human blood samples with minimal detection errors. Among the molecules that they used their new test to find was a mutated protein thought to be restricted to the inside of cells, mostly within the nucleus. It is the first time that single-molecule imaging has been applied to visualize disease-causing molecules in blood. They will present their research at the 63rd Biophysical Society Annual Meeting, to be held March 2—6, 2019 in Baltimore, Maryland.