Researchers at Emory University School of Medicine have adapted gene chip microarray technology to the study of glycans, with an approach they call "shotgun glycomics."
The Emory team has developed a new chemical method for attaching a fluorescent dye to glycans purified from cells. The individual glycans are separated into tiny spots fixed to glass slides.
The approach is described in an article published this week in the journal Nature Methods.
"These slides separate and display all the glycans in the cell, so that we can test what sticks to them," says senior author David Smith, PhD, professor of biochemistry and director of the Glycomics Center at Emory University School of Medicine. "However, the structures of the glycans are unknown. This is why we use the word 'shotgun' to describe our quasi-random approach of studying them."
The research team was led by Smith, first author Xuezheng Song, PhD, assistant professor of biochemistry, and Richard Cummings, PhD, chair of the Department of Biochemistry and co-director of the Glycomics Center.
As a demonstration of the technique's utility, the team used it to identify a molecule recognized by self-reactive antibodies present in the blood of most patients with Lyme disease. Lyme disease is caused by infection with Borrelia bacteria after a tick bite, but severe cases have features of an autoimmune response, triggered by the immune system's reaction to the bacteria.
"Being able to analyze glycans in this way may lead to new diagnostics for human autoimmune disorders, and perhaps, therapies to cleanse the body of self-reactive antibodies or inhibit their pathological attack on cells," Cummings says.
Completely dissecting glycans' structures is more difficult, compared with proteins or DNA, because glycans form branched structures in which not every link is chemically the same. Scientists have estimated that cells contain hundreds or thousands of different glycans, which can be attached to proteins or lipids. When using the shotgun approach, if scientists find that proteins from the body -- antibodies or toxins, for example -- bind to one particular glycan spot, they can then go back to that spot and determine its entire sequence, sifting out important glycans from the thousands on the slide.
"The sugars present on glycoproteins and glycolipids can contribute decisively to these molecules' functions," says Pamela Marino, PhD, who oversees glycobiology grants at the National Institutes of Health's National Institute of General Medical Sciences (NIGMS). "Understanding what information is encoded in these sugars and how they facilitate interactions with other proteins has been a major road block in deciphering the molecular language of glycans. This study, which is funded through the NIGMS EUREKA program for high risk research, has now provided proof of principle for an extremely novel 'shotgun' approach to interpreting this glycan code, and allows for examination of the role of glycans in infection and immunity."
The Emory team applied shotgun glycomics to red blood cells, tumor cells and brain-derived lipids. Cummings says the technique could be used to look for distinct sugar molecules displayed by cancer cells, for example. Identifying cancer-specific glycans could similarly lead to diagnostic tools or therapies, he says.
"A slide displaying glycans from a given cell type can be thought of as a book in the library, with the entire library constituting the human glycome," he says.
Reference: X. Song, Y. Lasanajak, B. Xia, J. Heimburg-Molinaro, J.M. Rhea, H. Ju, C. Zhao, R.J. Molinaro, R.D. Cummings and D.F. Smith. Shotgun glycomics: a microarray strategy for functional glycomics. Nature Methods (2010)
The Robert W. Woodruff Health Sciences Center of Emory University is an academic health science and service center focused on missions of teaching, research, health care and public service. Its components include the Emory University School of Medicine, Nell Hodgson Woodruff School of Nursing, and Rollins School of Public Health; Yerkes National Primate Research Center; Winship Cancer Institute of Emory University; and Emory Healthcare, the largest, most comprehensive health system in Georgia. Emory Healthcare includes: The Emory Clinic, Emory-Children's Center, Emory University Hospital, Emory University Hospital Midtown, Wesley Woods Center, and Emory University Orthopaedics & Spine Hospital. The Woodruff Health Sciences Center has a $2.5 billion budget, 17,600 employees, 2,500 full-time and 1,500 affiliated faculty, 4,700 students and trainees, and a $5.7 billion economic impact on metro Atlanta.
Learn more about Emory's health sciences: http://emoryhealthblog.com - @emoryhealthsci (Twitter) - http://emoryhealthsciences.org
Holly Korschun | EurekAlert!
Zebrafish's near 360 degree UV-vision knocks stripes off Google Street View
22.06.2018 | University of Sussex
New cellular pathway helps explain how inflammation leads to artery disease
22.06.2018 | Cedars-Sinai Medical Center
In a recent publication in the renowned journal Optica, scientists of Leibniz-Institute of Photonic Technology (Leibniz IPHT) in Jena showed that they can accurately control the optical properties of liquid-core fiber lasers and therefore their spectral band width by temperature and pressure tuning.
Already last year, the researchers provided experimental proof of a new dynamic of hybrid solitons– temporally and spectrally stationary light waves resulting...
Scientists from the University of Freiburg and the University of Basel identified a master regulator for bone regeneration. Prasad Shastri, Professor of...
Moving into its fourth decade, AchemAsia is setting out for new horizons: The International Expo and Innovation Forum for Sustainable Chemical Production will take place from 21-23 May 2019 in Shanghai, China. With an updated event profile, the eleventh edition focusses on topics that are especially relevant for the Chinese process industry, putting a strong emphasis on sustainability and innovation.
Founded in 1989 as a spin-off of ACHEMA to cater to the needs of China’s then developing industry, AchemAsia has since grown into a platform where the latest...
The BMBF-funded OWICELLS project was successfully completed with a final presentation at the BMW plant in Munich. The presentation demonstrated a Li-Fi communication with a mobile robot, while the robot carried out usual production processes (welding, moving and testing parts) in a 5x5m² production cell. The robust, optical wireless transmission is based on spatial diversity; in other words, data is sent and received simultaneously by several LEDs and several photodiodes. The system can transmit data at more than 100 Mbit/s and five milliseconds latency.
Modern production technologies in the automobile industry must become more flexible in order to fulfil individual customer requirements.
An international team of scientists has discovered a new way to transfer image information through multimodal fibers with almost no distortion - even if the fiber is bent. The results of the study, to which scientist from the Leibniz-Institute of Photonic Technology Jena (Leibniz IPHT) contributed, were published on 6thJune in the highly-cited journal Physical Review Letters.
Endoscopes allow doctors to see into a patient’s body like through a keyhole. Typically, the images are transmitted via a bundle of several hundreds of optical...
13.06.2018 | Event News
08.06.2018 | Event News
05.06.2018 | Event News
22.06.2018 | Materials Sciences
22.06.2018 | Earth Sciences
22.06.2018 | Life Sciences