Using conventional technologies, researchers supported by the National Cancer Institute (Science Applications International Corporation-Frederick, Inc (SAIC) have developed a new method for identifying proteins found in trace quantities in the blood.

The method offers hope for detecting tiny amounts of these blood-borne molecules that signal the presence of certain diseases, such as cancer, infectious diseases, behavioral disorders, developmental defects, and neurodegenerative diseases. These molecules might be useful biomarkers to aid in earlier detection and treatment of ovarian, breast and prostate cancer.

Prior efforts to identify low-abundance proteins were not as successful mainly because separation steps to reduce amounts of large, high-abundance proteins caused a simultaneous loss of the smaller, low-abundance proteins. Separation and fractionation are needed to produce samples that can be analyzed by mass spectrometry, a high-throughput technique for identifying individual proteins.

"Our investigation resulted in the identification of 1,444 proteins in serum," said Thomas Conrads, associate director of the Mass Spectrometry Center at NCI-Frederick. A wide range of proteins from different cellular compartments was identified. "This emphasizes the wide scope and complexity of the human serum proteome, which has been estimated to contain more than 10,000 proteins," he added.

This new method offers refinement, which may lead to identification of more sensitive disease markers, the company claims.

The National Cancer Institute (NCI) is part of the National Institutes of Health (NIH) and is the government's principal agency for cancer research.