Below please find the third issue of the newsletter of the 3D Cell Culture Core (3D3C) Facility of the Birck Nanotechnology Center. The newsletter is also available online (https://nanohub.org/groups/3d3cfacility/news).
The four sections in the newsletter are:
3D at Purdue – this section highlights 3D cell culture-based research activity at Purdue
3D in focus – this section presents the current work on a specific 3D cell culture model or technique
3D in publications – this section brings a collection of recent publications on 3D cell culture
3D in meetings – this section includes a list of upcoming meetings related to 3D cell culture
The newsletter will be available every two months. If you do not wish to receive the 3D3C newsletter in the future, please reply “cancel” to unsubscribe.
Please contact me if you have questions.
Yours Sincerely,
Tim Kwok
Facility Manager
3D Cell Culture Core (3D3C) Facility
Birck Nanotechnology Center
Purdue University
Volume 3, April 2016
3D at Purdue
3D in Focus
3D in Publications
3D in Meetings
3D at Purdue
Bumsoo Han, Purdue University Professor of mechanical engineering, has been working on developing a chip that stimulates the tumor "microenvironment". One of his goals is to use such system to test
the effectiveness of nanoparticles and drugs that target cancers. His work makes use of 3D bioprinting to create the tumor-microenvironment-on-chip (T-MOC) device with mimicry of aspects of the complex environment around tumors necessary to assess movements
of particles out of blood vessels and within the tumor tissue. The idea is to use this system to gather information about the ways by which nanoparticles move through the microenvironment. The T-MOC chip is about 4.5 centimeters (1.8 inches) square. It consists
of three-dimensional microfluidic channels in which tumor cells and endothelial cells are embedded within extracellular matrix and under perfusion of interstitial fluid regulated by pressure reservoirs.
In theory, to target the tumor tissue effectively without harming the rest of the body, agent delivery particles can be used that are small enough to pass through the pores located in blood vessels surrounding tumors but also large enough not to pass though
the pores of vessels present in healthy tissue. The endothelial cells in the normal blood vessels are well organized and have only small pores in the tight junctions that connect them. However, the endothelial cells in blood vessels around tumors are not well-organized.
Notably, larger pores than normal are present. Logically, once injected in the blood stream agent delivery particles of well-chosen size should be capable of selectively moving out of the vessels only in the tumor tissue. However, the pressure of "interstitial
fluid" inside tumors is greater than that of the surrounding healthy tissue. The greater pressure inside the tumor may push out most drug-delivery systems and imaging agents, leaving only a small percentage of them inside the tumor. This is why there is a
need for a better understanding of movements of agent delivery particles in the tumor surroundings.
Professor Han’s research group constructed the T-MOC chip (see Figure) by embedding human breast cancer and endothelial cells in the extracellular matrix, a spongy, scaffold-like material made of collagen I, as a main component, located in a compartment called
the interstitium in living tissues. The transport of nanoparticles and its variation have been studied by the Han’s team with respect to tumor microenvironmental parameters such as cut-off pore size, interstitial fluid pressure, and tumor tissue microstructure.
Findings confirm that nanoparticles should be designed by taking into account their dynamic interactions with the tumor microenvironment.
This work was highlighted in Purdue Today (by Emil Venere March 1 2016) and part of the results have been published in the
Journal of Control Release*.
* Kwak B, Ozcelikkale A, Shin CS, Park K, Han B Simulation of complex transport of nanoparticles around a tumor using tumor-microenvironment-on-chip Journal of Controlled Release 194 (2014) 157–167
Drawing of the T-MOC (courtesy of Dr. Bumsoo Han)
3D in Focus
In this newsletter editorial, we chose to highlight work done to study how three-dimensional (3D) microenvironments may increase the reprogramming efficacy of somatic cells into induced pluripotent
stem cells (iPSCs).
Caiazzo M, Okawa Y, Ranga A, Piersigilli A, Tabata Y, Lutolf MP
Defined three-dimensional microenvironments boost induction of pluripotency. Nat Mater. 2016 Mar; 15(3):344-52.
Indeed standard 2D cell culture systems have had only limited success in terms of iPSC yield. The iPSCs are reprogrammed somatic cells prepared from a variety of tissue sources and genetic background.
These cells can proliferate without limit and also maintain the potential to generate derivatives of all three embryonic germ layers (ectoderm, endoderm, or mesoderm), as such being the potential sources for different cell types like neurons, cardiomyocytes
and hepatocytes. Therefore, iPSCs can be a powerful tool for regenerative medicine, disease modeling, drug screening, and precision medicine. Improving the yield of iPSCs will be greatly necessary and important in its future application in disease modeling
and therapy.
In the experiments by Caiazzo et al., the enhanced power of the 3D microenvironment over standard 2D cell culture on the induction efficacy of pluripotency was first confirmed by embedding mouse embryonic stem cells in poly(ethyleneglycol) (PEG)-based
hydrogels. In the subsequent study on iPSCs from somatic origin, the authors engineered a mouse system expressing the four Yamanaka factors (Oct4,
Sox2, Klf4 and c-Myc) that are known to be essential for the induction of pluripotency in somatic cells. Achievement of pluripotency was monitored by an
Oct4–GFP (green fluorescence protein) reporter system. Mouse tail-tip fibroblasts were encapsulated in the PEG-based hydrogels and the reprogramming efficacy was subsequently assessed based on the number of
Oct4–GFP-positive iPSC colonies forming in the gels. The authors proposed that the 3D microenvironment keeps cells in an active proliferation state throughout the entire reprogramming process and that the production of iPSCs might be faster under 3D
culture conditions.
Following the use of a 3D high-throughput screening approach to simultaneously probe 128 unique microenvironmental conditions, the authors concluded that the use of PEG-hydrogels with stiffness between 300 and 600 Pa, the enrichment of the microenvironment
with laminin or EpCAM in the hydrogels, and the activation of the Wnt pathway, all led to marked improvements in reprogramming efficacy. Importantly, the physical confinement of cells imposed by the 3D microenvironment increased the reprogramming efficacy
(measured by the number of colonies formed) of both mouse and human iPSCs by more than two-fold. Experiments also showed that early steps during reprogramming in 3D cell culture that lead to the formation of colonies, may cause both chromatin remodeling and
accelerated mesenchymal-to-epithelial transition, two key events for the initiation of iPSC generation. Moreover, the increase in reprogramming efficacy comparable to that of PEG was also demonstrated in cells embedded in Matrigel.
Overall, the study demonstrates that the modulation of the microenvironment in 3D cell culture is crucial to improve reprogramming effectiveness to a level that may not be achievable with 2D cell culture.
3D Cell Culture 2016 (3DCC 2016)
Date: 18th to 21st April 2016
Location: Freiburg, Germany
Organized by: DECHEMA, Gesellschaft für Chemische Technik und Biotechnologie e.V
Website:
http://www.dechema.de/3DCC2016.html
3rd 3D Models & Drug Screening Conference
Date: 11th to 12th May 2016
Location: Berlin, Germany
Website
https://www.gtcbio.com/conferences/3d-models-drug-screening-overview
Contact Person - Kristen Starkey
Event enquiries email address - infogtcbio@gtcbio.com
Deadline for abstracts/proposals: 2016-04-11
Organized by: GTCbio
Healthcare of the Future: Analytics, Wearables, 3D Printing and Digital Innovations conference 2016
Date: 15th to 17th June 2016
Location: Sydney, Australia
Website:
http://claridenglobal.com/conference/au-digitalhealthcare2016/
Contact person: Sherin Edward
Organized by: Clariden Global International Limited
2nd EACR Conference on Goodbye Flat Biology: Models, Mechanisms and Microenvironment
Date: 2nd to 5th October 2016
Location: Berlin, Germany
Website:
http://www.eacr.org/goodbyeflatbiology2016/index.php
Contact person: Roger Doxat-Pratt
The meeting should be of interest to all those who use cancer cell lines, patient-derived tissue samples or primary cultures in vitro for the study of tumour biology, bioengineering and biochemistry, drug target validation, etc.
Organized by: European Association for Cancer Research
Deadline for abstracts/proposals: 20th June 2016
