Delivered to its intracellular target via a novel carrier, 'BINDI' suppresses tumor growth and extends survival in a lab model of lymphoma
A protein molecule, "BINDI," has been built to trigger self-destruction of cancer cells infected with the Epstein-Barr virus. Numerous cancers are linked to the Epstein-Barr virus, which can disrupt the body's weeding of old, abnormal, infected and damaged cells.
A small chunk of protein (red) bound to the Epstein-Barr virus target protein (gray) was extended to make a much longer protein, left, and then designed to have a rigid folded structure, right, for tight and specific interactions with the target.
Credit: UW Molecular Engineering and Sciences Institute
The Epstein-Barr virus persists for a long time after a bout with mononucleosis or other diseases for which it is responsible. It survives by preventing cells from disintegrating to kill themselves and their invaders. The virus' interference with cell population control may contribute to cancerous overgrowth.
In a June 19 report in the scientific journal Cell, researchers describe how they computer-designed, engineered and tested a protein that overrides the virus' interference. BINDI, they discovered, can prompt Epstein-Barr-infected cancer cell lines to shrivel, disassemble their components and burst into small pieces.
The BINDI protein was created at the UW Institute for Protein Design. (BINDI is an acronym for BHRF1-INhibiting Design acting Intracellularly.)
Lead authors of the paper are Erik Procko of the Department of Biochemistry and Geoffrey Y. Berguig of the Department of Bioengineering, both at the University of Washington. They collaborated with scientists and clinicians at the UW, Fred Hutchinson Cancer Research Center, Seattle Cancer Care Alliance and Scripps Research Institute.
The research team also tested the protein in a laboratory model of Epstein-Barr virus-positive lymphoma. Lymphoma is a type of cancer that can affect the lymph nodes, spleen, bone marrow, blood and other areas of the body. The researchers grafted lymphoma tissue onto mice as a living system to evaluate BINDI's therapeutic properties.
The scientists delivered the protein into cancer cells via an antibody-targeted nanocarrier newly designed to deliver protein cargo to intracellular cancer targets. BINDI behaved as ordered: It suppressed tumor growth and enabled the mice to live longer.
"We are especially interested in designing proteins that selectively kill targeted cells," the researchers noted, "because they may provide advantages over current compounds that are toxic to other cells."
The work also demonstrates the potential to develop new classes of intracellular protein drugs, as current protein therapeutics are limited to extracellular targets.
BINDI was designed to recognize and attach itself to an Epstein-Barr virus protein called BHRF1, and to ignore similar proteins. BHRF1 keeps cancer cells alive, but when bound to BINDI, it can no longer fend off cell death.
By examining the crystal structure of BINDI, the scientists saw that it nearly matched their computationally designed architecture for the protein molecule.
"This close agreement between the protein model and the actual structure highlights the success in which designer toxins can be developed," the researchers said.
Among the scientists on this project:
Grants from the National Institute of General Medical Studies at the National Institutes of Health (P41 GM103533, R01 GM49857, R21EB014572), Washington Life Sciences Discovery Fund and the U.S. Defense Threat Reduction Agency supported this project. Computational resources came from Berkeley Open Infrastructure for Network Computing, which received National Science Foundation support.
Stayton and Press are co-founders of PhaseRx Pharmaceuticals, which holds licenses for aspects of the new drug delivery carrier tested in this study, but indicated that the work reported is independent of the firm.
Elizabeth Hunter | Eurek Alert!
Bacteria as pacemaker for the intestine
22.11.2017 | Christian-Albrechts-Universität zu Kiel
Researchers identify how bacterium survives in oxygen-poor environments
22.11.2017 | Columbia University
The WHO reports an estimated 429,000 malaria deaths each year. The disease mostly affects tropical and subtropical regions and in particular the African continent. The Fraunhofer Institute for Silicate Research ISC teamed up with the Fraunhofer Institute for Molecular Biology and Applied Ecology IME and the Institute of Tropical Medicine at the University of Tübingen for a new test method to detect malaria parasites in blood. The idea of the research project “NanoFRET” is to develop a highly sensitive and reliable rapid diagnostic test so that patient treatment can begin as early as possible.
Malaria is caused by parasites transmitted by mosquito bite. The most dangerous form of malaria is malaria tropica. Left untreated, it is fatal in most cases....
The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.
Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...
Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.
That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...
Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.
During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....
The quantum world is fragile; error correction codes are needed to protect the information stored in a quantum object from the deteriorating effects of noise. Quantum physicists in Innsbruck have developed a protocol to pass quantum information between differently encoded building blocks of a future quantum computer, such as processors and memories. Scientists may use this protocol in the future to build a data bus for quantum computers. The researchers have published their work in the journal Nature Communications.
Future quantum computers will be able to solve problems where conventional computers fail today. We are still far away from any large-scale implementation,...
15.11.2017 | Event News
15.11.2017 | Event News
30.10.2017 | Event News
22.11.2017 | Business and Finance
22.11.2017 | Physics and Astronomy
22.11.2017 | Physics and Astronomy