New 'library' aids detection of antibodies

U.S. Department of Energy scientists and an MIT colleague have created a library of 1 billion human antibodies on the surface of yeast cells. The work will speed the search for new antibodies, proteins that are effective tools for recognizing specific molecules. It also promises to make the hunt less expensive. “Antibodies are assuming increasingly important roles in such diverse fields as sensors, proteomics, diagnostics, and therapeutics. We have captured a broad sample of the antibody diversity present in adult humans, and expressed it on the surface of yeast cells in a format suitable for quantitative screening,” said K. Dane Wittrup, J.R. Mares Professor of Chemical Engineering and Bioengineering. The technology, reported in the February issue of Nature Biotechnology, “provides a robust and direct route to the isolation of useful antibodies” outside a living body, he continued. As a result, it could replace the need to produce antibodies within animals, such as mice. It also opens up new possibilities for rapidly designing medical treatments more acceptable to the human immune system.

New antibody library speeds search for new detection tools

Scientists at the Department of Energy’s Pacific Northwest National Laboratory have extracted part of the human immune system and reconstituted it in brewer’s yeast in a fashion that enables powerful machines to quickly identify new antibodies. The advance could have major repercussions for fundamental biological science as well as industries that use antibodies for sensors, biodetectors, diagnostic tools and therapeutic agents.

Blasting antibodies with lasers measures their flexibility

A group of scientists have used a powerful laser in combination with innovative quantum mechanical computations to measure the flexibility of mouse antibodies. The new technique, described in an upcoming issue of the journal Proceedings of the National Academy of Sciences, is significant because protein flexibility is believed to play an important role in antibody — antigen recognition, one of the fundamental events in the human immune system. “This is the first time anybody has ever gone into a protein and experimentally measured the frequency of vibrations in response to an applied force,” said Floyd Romesberg, assistant professor in the Department of Chemistry at The Scripps Research Institute, who led the study.

‘Outlaw’ organism turns informant

In a critical scene in the film remake of the classic 1960s TV series “The Fugitive,” actor Harrison Ford sheds his coat and replaces it with another. This simple deception allows him to escape detection by the swarm of police officers trailing him. The African trypanosome, a blood parasite that causes African sleeping sickness, is, like Ford’s character in the film, a fugitive that changes its “coat” each time the human immune system is about to nab it. Woven of 10 million copies of a single sugar-coated molecule called a glycoprotein, the trypanosome’s surface changes every few days by virtue of a switch that activates a new gene.