In adults, mesenchymal stems cells (MSCs) are primarily found in bone marrow and they play a vital role in repair of damaged organs. The transformation of a single MSC into complex tissue like cartilage and bone starts with its association with other MSCs in order to form microscopic clusters via a process termed as condensation.
While it is known that this condensation step is important for skeletal development the exact role it plays in formation of bone and cartilage is not understood. A team led by Prof. Dr. Prasad Shastri and Dr. Melika Sarem of the Institute for Macromolecular Chemistry at the University of Freiburg present evidence for autonomous control of chondrogenesis in MSCs. These findings are published in the journal “Stem Cell Research & Therapy“.
They discovered that reducing the number of cells participating in condensation process leads to the activation of an intrinsic differentiation program. This prompts MSCs to become cartilage cells even in absence of chondro-inductive growth factors irrespective of donor age and sex. Sarem and Shastri further identified that two cell-membrane proteins, Caveolin-1 and N-Cadherin are differentially regulated during the condensation step and function as interactive forces like a Yin-Yang of chondrogenic differentiation.
"The fact that we need lesser cells to create better quality tissue is extremely exciting as it opens new avenues for stem cell therapies" summarizes Sarem.
In collaboration with Dr. Oliver Otto, at the University of Greifswald, the Freiburg researchers demonstrated that the chondrogenic potential of MSCs correlates with emergence of a stiffer phenotype and increase in cell size. Their findings allude to a hitherto unknown mechanobiology paradigm in MSC differentiation.
“Since MSCs harvested from adult bone marrow are a heterogeneous population of cells and their ability to undergo differentiation into cartilage or bone cells varies from donor to donor, our findings have significant implication for MSC-based strategies for engineering cartilage and bone tissue,” explains Shastri.
Prasad Shastri is the Professor of Biofunctional Macromolecular Chemistry at the Institute for Macromolecular Chemistry and the Professor of Cell Signalling Environments in the Cluster of Excellence BIOSS Centre for Biological Signalling Studies at the University of Freiburg.
Sarem, M., Otto, O., Tanaka, S., Shastri, V. P. (2019): Cell number in mesenchymal stem cell aggregates dictates cell stiffness an chondrogenesis. In: Stem Cell Research & Therapy. DOI: 10.1186/s13287-018-1103-y
Immunofluorescence staining of matrix proteins in engineered cartilage
Prof. Dr. Prasad Shastri
Institut für Makromolekulare Chemie & BIOSS Centre for Biological Signalling Studies
University of Freiburg
Rudolf-Werner Dreier | idw - Informationsdienst Wissenschaft
Happy hour for time-resolved crystallography
17.09.2019 | Max-Planck-Institut für Struktur und Dynamik der Materie
Too much of a good thing: overactive immune cells trigger inflammation
16.09.2019 | Universität Basel
Researchers from the Department of Atomically Resolved Dynamics of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg, the University of Hamburg and the European Molecular Biology Laboratory (EMBL) outstation in the city have developed a new method to watch biomolecules at work. This method dramatically simplifies starting enzymatic reactions by mixing a cocktail of small amounts of liquids with protein crystals. Determination of the protein structures at different times after mixing can be assembled into a time-lapse sequence that shows the molecular foundations of biology.
The functions of biomolecules are determined by their motions and structural changes. Yet it is a formidable challenge to understand these dynamic motions.
At the International Symposium on Automotive Lighting 2019 (ISAL) in Darmstadt from September 23 to 25, 2019, the Fraunhofer Institute for Organic Electronics, Electron Beam and Plasma Technology FEP, a provider of research and development services in the field of organic electronics, will present OLED light strips of any length with additional functionalities for the first time at booth no. 37.
Almost everyone is familiar with light strips for interior design. LED strips are available by the metre in DIY stores around the corner and are just as often...
Later during this century, around 2060, a paradigm shift in global energy consumption is expected: we will spend more energy for cooling than for heating....
Researchers from the Department of Atomically Resolved Dynamics of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg, the University of Potsdam (both in Germany) and the University of Toronto (Canada) have pieced together a detailed time-lapse movie revealing all the major steps during the catalytic cycle of an enzyme. Surprisingly, the communication between the protein units is accomplished via a water-network akin to a string telephone. This communication is aligned with a ‘breathing’ motion, that is the expansion and contraction of the protein.
This time-lapse sequence of structures reveals dynamic motions as a fundamental element in the molecular foundations of biology.
Two research teams have succeeded simultaneously in measuring the long-sought Thorium nuclear transition, which enables extremely precise nuclear clocks. TU Wien (Vienna) is part of both teams.
If you want to build the most accurate clock in the world, you need something that "ticks" very fast and extremely precise. In an atomic clock, electrons are...
10.09.2019 | Event News
04.09.2019 | Event News
29.08.2019 | Event News
17.09.2019 | Materials Sciences
17.09.2019 | Health and Medicine
17.09.2019 | Ecology, The Environment and Conservation