Previous studies have shown that stromal cells regulate the proliferation and differentiation of HSCs through the production of diffusible hematopoietic regulatory factors and extracellular matrix, and through physical cell-cell interactions involving adhesion molecules and gap junction-mediated cell communication.
However, the ability of stromal cells to support the expansion of HSCs and to maintain their self-renewal potential has generally been investigated in long-term, two-dimensional (2D) bone marrow culture systems (BMCS), and most of the reports have shown a decline in HSCs within 4 weeks in culture.
In work published in the November 2011 issue of Experimental Biology and Medicine, Hirabayashi and co-investigators from Nihon University School of Medicine, Osaka Prefecture University and the Norwegian University of Science and Technology have developed a new three-dimensional (3D) BMCS. As stated by co-author Isao Tsuboi, "2D BMCS can't maintain HSCs for a long time, which does not enable us to analyze stromal-cell function. Therefore, we developed a new 3D BMCS and succeeded to maintain HSCs for much longer time."
This new 3D BMCS is based on unique particles. As explained by co-author Yukio Hirabayashi, "The polymer particle with grafted epoxy-polymer-chains is most important in our 3D BMCS. We selected the particle most suitable for cell culture from more than 20 types of particles with various grafted polymer chain lengths and its surface density, the composition of base polymer network and graft polymer chain. We named this particle G-02". Furthermore, co-author Tomonori Harada adds "Several kinds of cell lines, other than murine fibroblast cell line (MS-5 cell), such as an epidermal cell line (HeLa cell), osteoblast cell line (MC3T3E1 cell) and chondrocyte cell line (ch-8 cell), can adhere easily on the G-02 particle and proliferate rapidly on its surface. This advantage of the G-02 particle enables us to develop 3D BMCS, which can also be applied to other 3D organ cultures of central nerve system, heart and liver."
CD34 is well known to be a surface marker for human primitive hematopoietic progenitor cells, however, CD34+ cells can also differentiate into stromal cells. When CD34+ cells are co-cultured with human stromal cells, it is complex to clarify the biological function of the preestablished stromal cell layer. Prof. Shin Aizawa, group leader and pioneer in the study of stromal cell, says "In this study, we used a murine stromal cell line (MS-5) instead of human stromal cells to exclude the effect of CD34+ derived stromal cells. This co-culture system makes it possible to distinguish the function of MS-5 stromal-cell layer from that of CD34+ derived stromal cells. Now our group is studying gene-expression levels of various cytokines in stromal cells using specific primers and probes for the mouse and human".
Steven R. Goodman, Ph.D. Editor-in-Chief of Experimental Biology and Medicine said "this 3-dimensional bone marrow culture system, developed by Hirabayashi and coworkers, should be an outstanding tool for the study stromal cell function".
Experimental Biology and Medicine is a journal dedicated to the publication of multidisciplinary and interdisciplinary research in the biomedical sciences. The journal was first established in 1903. Experimental Biology and Medicine is the journal of the Society of Experimental Biology and Medicine. To learn about the benefits of society membership visit www.sebm.org. If you are interested in publishing in the journal please visit http://ebm.rsmjournals.com.
Dr. Tomonori Harada | EurekAlert!
Multi-institutional collaboration uncovers how molecular machines assemble
02.12.2016 | Salk Institute
Fertilized egg cells trigger and monitor loss of sperm’s epigenetic memory
02.12.2016 | IMBA - Institut für Molekulare Biotechnologie der Österreichischen Akademie der Wissenschaften GmbH
A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.
Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...
In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.
“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...
The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.
The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...
Broadband rotational spectroscopy unravels structural reshaping of isolated molecules in the gas phase to accommodate water
In two recent publications in the Journal of Chemical Physics and in the Journal of Physical Chemistry Letters, researchers around Melanie Schnell from the Max...
The efficiency of power electronic systems is not solely dependent on electrical efficiency but also on weight, for example, in mobile systems. When the weight of relevant components and devices in airplanes, for instance, is reduced, fuel savings can be achieved and correspondingly greenhouse gas emissions decreased. New materials and components based on gallium nitride (GaN) can help to reduce weight and increase the efficiency. With these new materials, power electronic switches can be operated at higher switching frequency, resulting in higher power density and lower material costs.
Researchers at the Fraunhofer Institute for Solar Energy Systems ISE together with partners have investigated how these materials can be used to make power...
16.11.2016 | Event News
01.11.2016 | Event News
14.10.2016 | Event News
02.12.2016 | Medical Engineering
02.12.2016 | Agricultural and Forestry Science
02.12.2016 | Physics and Astronomy