RICHLAND, Wash. -- Combining two well-established analytic techniques and adding a twist identifies proteins from blood with as much accuracy and sensitivity as the antibody-based tests used clinically, researchers report this week in Proceedings of the National Academy of Sciences Early Edition online. The technique should be able to speed up development of diagnostic tests and treatments based on proteins specific to certain diseases.
The team of scientists at the Department of Energy's Pacific Northwest National Laboratory found that their technique, called PRISM, performed as accurately as standard clinical tests known as ELISAs in a head-to-head comparison using blood samples from cancer patients. The tests measure biomarkers, proteins whose presence identifies a disease or condition.
"Clinical tests have almost always used antibodies to measure biomarkers, because antibodies can provide good sensitivity," said PNNL bioanalytical chemist Wei-Jun Qian, lead author on the study. "But it often takes a year and a half to develop antibodies as tools. Antibody development is one of the bottlenecks for new biomarker studies in disease and systems biology research."
Qian, Tujin Shi, Tom Fillmore and their PNNL colleagues worked out the highly sensitive PRISM using resources at DOE's EMSL, the Environmental Molecular Sciences Laboratory on PNNL's campus. The result is a simple and elegant integration of existing technologies that solves a long-standing problem.
Researchers have long wanted to use mass spectrometry to identify proteins of interest within biological samples. Proteins are easy to detect with mass spec, but it lacks the sensitivity to detect rare proteins that exist in very low concentrations. Scientists use antibodies to detect those rare proteins, which work like a magnet pulling a nail out of a haystack.
Antibodies are immune system molecules that recognize proteins
|Contact: Mary Beckman|
DOE/Pacific Northwest National Laboratory