Our brain consists of countless nerve cells that transmit signals from one cell to the next. The connections between these cells, the synapses, provide a key to understanding how our memory works. An American research team in collaboration with Rainer Heintzmann from the Leibniz Institute of Photonic Technology (Leibniz IPHT) and the Friedrich Schiller University Jena has now succeeded in identifying these switching points in millimeter-sized tissue with a light microscope on the basis of their structure. The scientists published their results on 31 October 2019 in Nature Methods.
To make the synapses visible, the research team at Southwestern University Texas, led by Reto Fiolka and Kevin Dean, developed a special microscope. The scientists illuminate a tissue sample approximately one millimeter in size from the side with wedge-shaped focused light. While the focus of this light wedge shifts, image data is recorded.
This enables the researchers to use machine learning to identify and visualize three-dimensional tissue structures within the cells in high resolution and true to scale. Depending on the optical configuration, the microscope provides up to 260 nm of axial resolution, a three to tenfold improvement over confocal and other reported cleared-tissue light-sheet microscopes.
The research team imaged millimeter-scale cleared tissues with subcellular three-dimensional resolution, which enabled automated detection of multicellular tissue architectures, individual cells, synaptic spines and rare cell–cell interactions.
"This work is groundbreaking. The recognition of synapses in millimeter-sized tissue using the light microscope only on the basis of their structure has long been a dream of scientists," said Rainer Heintzmann from Leibniz IPHT.
He calculated the expected light distribution and thus the quality of the wedge focus. "The calculations are important for the optical design of the instrument," explains Rainer Heintzmann. "They take into account the unwanted influence that the non-ideal refractive index of the embedding medium has on the quality of the focus. "
The research team believes their method will expedite human cell atlas efforts, providing much- needed insight into how tissue function manifests in health and disease, from the heterogenous cellular populations that compose it. Scientists around the world are working on three-dimensional imaging and characterization of all cells in the human body.
The Human Cell Atlas is intended to create comprehensive reference maps of all human cells to contribute to a better understanding of how fundamental processes in our organism take place and how they change when we become ill, thus helping to enable better diagnosis and treatment.
Prof. Dr. Rainer Heintzmann
Head of the Microscopy Research Department
+49 (0) 3641 · 206-431
T. Chakraborty et al., Nature Methods 16, 1109-1113, 2019; https://doi.org/10.1038/s41592-019-0615-4
Lavinia Meier-Ewert | idw - Informationsdienst Wissenschaft
The Screw That Dissolves
06.11.2019 | Empa - Eidgenössische Materialprüfungs- und Forschungsanstalt
Attacking metastatic breast cancer with sound
28.10.2019 | Tohoku University
In two experiments performed at the free-electron laser FLASH in Hamburg a cooperation led by physicists from the Heidelberg Max Planck Institute for Nuclear physics (MPIK) demonstrated strongly-driven nonlinear interaction of ultrashort extreme-ultraviolet (XUV) laser pulses with atoms and ions. The powerful excitation of an electron pair in helium was found to compete with the ultrafast decay, which temporarily may even lead to population inversion. Resonant transitions in doubly charged neon ions were shifted in energy, and observed by XUV-XUV pump-probe transient absorption spectroscopy.
An international team led by physicists from the MPIK reports on new results for efficient two-electron excitations in helium driven by strong and ultrashort...
An international research group has observed new quantum properties on an artificial giant atom and has now published its results in the high-ranking journal Nature Physics. The quantum system under investigation apparently has a memory - a new finding that could be used to build a quantum computer.
The research group, consisting of German, Swedish and Indian scientists, has investigated an artificial quantum system and found new properties.
Researchers at the U.S. Department of Energy's (DOE) Argonne National Laboratory have reported a new mechanism to speed up the charging of lithium-ion...
Northwestern University chemists have used visible light and extremely tiny nanoparticles to quickly and simply make molecules that are of the same class as...
Almost everyone uses nanometer-sized alumina these days - this mineral, among others, constitutes the skeleton of modern catalytic converters in cars. Until now, the practical production of nanocorundum with a sufficiently high porosity has not been possible. The situation has changed radically with the presentation of a new method of nanocorundum production, developed as part of a German-Polish cooperation of scientists from Mülheim an der Ruhr and Cracow.
High temperatures and pressures, processes lasting for even dozens of days. Current methods of producing nanometer-sized alumina, a material of significant...
05.11.2019 | Event News
30.10.2019 | Event News
02.10.2019 | Event News
08.11.2019 | Life Sciences
08.11.2019 | Medical Engineering
07.11.2019 | Power and Electrical Engineering