A team of researchers affiliated with Ludwig Cancer Research and the Karolinska Institutet in Sweden report in the current issue of Nature Methods a dramatically improved technique for analyzing the genes expressed within a single cell -- a capability of relevance to everything from basic research to future cancer diagnostics.
"There are cells in tumors and in healthy tissues that are not present in sufficient numbers to permit analysis using anything but single-cell methods," explains senior author, Rickard Sandberg, PhD. "This method allows us to identify rare and important subpopulations of cells in all sorts of tissues. We can also use it to tease apart, more rigorously than ever before, how the expression of unique suites of genes transform cells from one state to another as, say, an embryo develops into an organism, or a tumor becomes metastatic."
Traditional approaches, which depend on the collective analysis of gene expression in millions of cells at once, tend to obscure biologically significant differences in the genes expressed by specialized cells within a particular kind of tissue. Single-cell analysis of gene expression overcomes this limitation. The leading method for such analysis -- Smart-seq -- was developed in 2012 by the biotechnology firm Illumina, together with Sandberg's laboratory.
To develop the new technique, named Smart-seq2, Sandberg's team conducted more than 450 experiments to improve upon their initial method. The new procedure consistently captures three to four times as many RNA molecules, which often translates into 2,000 more genes per cell than current methods allow. It also captures far more full-length gene sequences, a steep challenge in such studies, which often capture only partial sequences of expressed genes. This will permit researchers to conduct a more granular analysis of how subtle differences between the same genes in different people -- known as single nucleotide polymorphisms (or SNPs) -- contribute to differences in biology and disease.
The new method is likely to be of great value to cancer research. Identifying rare sub-populations of cells in tumors and understanding their role in the survival and progression of cancers can provide invaluable information for the development of diagnostics and targeted therapies. A study recently published by Ludwig researchers described, for example, how certain subpopulations of cells in melanomas can be pushed into a drug-susceptible state and then destroyed by chemotherapy. More such strategies might be devised as researchers get a better handle on the cellular species found in different types of tumors, and the patterns of gene expression that define them.
Because Smart-seq2 relies on off-the-shelf reagents, it costs roughly a twentieth as much as the commercialized kit, which should allow researchers to conduct sophisticated analyses of single cells on a much larger scale. It can also be improved further by the scientific community, since its constituent components and rationale are both open to the public.
Armed with the more effective and affordable Smart-seq2, Sandberg's lab is now moving ahead on projects that require a large-scale, single-cell gene expression analysis. "Now all researchers can do their own single-cell gene expression analysis by buying the components of the process described in this paper and assembling their own kits," says Sandberg.
Rickard Sandberg is an assistant member at the Ludwig Institute for Cancer Research and associate professor and principal investigator at the Department of Cell and Molecular Biology, Karolinska Institutet. This study was funded with grants from the European Research Council, the Swedish Foundation for Strategic Research, and the Swedish Research Council.
For more information on Sandberg's research, please click here: http://www.ludwigcancerresearch.org/location/stockholm-branch/rickard-sandberg-lab.
About Ludwig Cancer Research
Ludwig Cancer Research is an international collaborative network of acclaimed scientists with a 40-year legacy of pioneering cancer discoveries. Ludwig combines basic research with the ability to translate its discoveries and conduct clinical trials to accelerate the development of new cancer diagnostics and therapies. Since 1971, Ludwig has invested more than $1.6 billion in life-changing cancer research through the not-for-profit Ludwig Institute for Cancer Research and the six U.S.-based Ludwig Centers. http://www.ludwigcancerresearch.org
About Karolinska Institutet
Karolinska Institutet is one of the world's leading medical universities. It accounts for over 40 per cent of the medical academic research conducted in Sweden and offers the country's broadest range of education in medicine and health sciences. Since 1901 the Nobel Assembly at Karolinska Institutet has selected the Nobel laureates in Physiology or Medicine. More on ki.se/english
For further information, please contact Rachel Steinhardt, firstname.lastname@example.org or +1-212-450-1582 or the Press Office at Karolinska Institutet, email@example.com or +46 (0)8-524 860 77.
Scientists uncover the role of a protein in production & survival of myelin-forming cells
19.07.2018 | Advanced Science Research Center, GC/CUNY
NYSCF researchers develop novel bioengineering technique for personalized bone grafts
18.07.2018 | New York Stem Cell Foundation
A new manufacturing technique uses a process similar to newspaper printing to form smoother and more flexible metals for making ultrafast electronic devices.
The low-cost process, developed by Purdue University researchers, combines tools already used in industry for manufacturing metals on a large scale, but uses...
For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.
To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...
For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.
Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...
Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.
A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...
Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.
"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....
13.07.2018 | Event News
12.07.2018 | Event News
03.07.2018 | Event News
20.07.2018 | Power and Electrical Engineering
20.07.2018 | Information Technology
20.07.2018 | Materials Sciences