2019
On-chip vasculature for three-dimensional tissue culture and microphysiological systems
by Pr. Ryuji Yokokawa, Department of Micro Engineering, Kyoto University
Micro/nano fabrication technologies have prevailed among many biological research disciplines. Expecting that micro/nano fabrications can be a powerful assay platform, our group has been focusing on applicability of fabrication technologies to multi-scale biomaterials from proteins to cells. We currently have two research directions: One is patterning methods for motor proteins that contribute to their biophysical studies. We developed a molecular sorter to separate microtubules depending on their electro-mechanical properties, and to visualize motors and ATP at single molecule level. More recently, nano-pillars were utilized to immobilize single individual motor proteins and revealed that two different motor proteins behave differently.
In this presentation, I will mainly focus on a patterning method of endothelial cells for creating an on-chip vascular network that allows us to culture three-dimensional tissues. We developed an on-chip vascular network using human umbilical vein endothelial cells (HUVECs) and human lung fibroblasts (hLFs). The vascular network in the figure enables us to perfuse a spheroid for a long-term assay and evaluate angiogenic sprouts via applied shear stress. The assay method was also applied to a tumor spheroid to evaluate the efficacy of an anti-tumor drug under a flow condition, which was not realized without the microfluidic device. We have proposed several bioassays that create functional nanoscale systems and contribute to understanding of in vivo functions of motor proteins and endothelial cells. We keep exploring how micro/nano fabrications can deepen science both at molecular and cellular scale.
Microfluidic devices to study cancer and infection
by Pr. Tadashi Ishida, Tokyo Institute of Technology
Medicine is important to cure disease using chemical drugs. However, some diseases, especially cancer and bacterial infection, are difficult to be cured by medicines. As for cancer, one of the main problems is side effects of anti-cancer drugs. To reduce the side effects, cancer specific binding molecules are required. We developed a screening microfluidic device for cancer specific binding peptides by combining cell seeding pillars, pneumatic microvalves and filter chambers. As for bacterial infection, bacteria acquired many resistances to anti-bacterial drugs. It is difficult to find new anti-bacterial drugs due to the lack of methods. We believe high-resolution visualization of bacteria in-liquid can be helpful to find new action mechanisms of anti-bacterial drugs. We developed an scanning electron microscopy for water containing structures, and observed in-liquid bacteria.
MEMS Vibratory Energy Harvesters to Power IoT Wireless Sensors
by Pr. Daisuke Yamane, IIR, Tokyo Institute of Technology
MEMS (microelectromechanical systems) vibratory energy harvester would be a promising device for one of the future power sources for IoT (internet-of-things) wireless self-powered sensors because of the abundant energy sources of environmental vibrations found indoors and outdoors around the clock. In this talk, the speaker introduces his research along with the latest technology trends.
2018
Organic Transistor-based Biosensors
by Pr. Tsuyoshi Minami, The University of Tokyo
In the realm of electronics, organic thin-film transistors (OTFTs) are some of the most interesting devices owing to their flexibility, solution-processability and ultra-small thickness. Recently, interest in OTFTs and their advantages have extended beyond rollable information displays to sensor applications. OTFT-based physical sensors are being researched extensively, while chemical sensors are still in their early stages. In this regard, my group is developing OTFT-based chemical sensors functionalized with supramolecular artificial receptors, enzymes or immune proteins. In my talk, I would like to show the latest results in biosensing applications of OTFTs for saccharides, immunoglobulins, small ionic species, etc.
Modelling a nervous tissue with human iPS cell-derived tissues
by Pr. Yoshiho Ikeuchi, The University of Tokyo
Molecular gradient and physical pattern guide development of the brain and the nervous system. We are developing tools to recapitulate the developmental mechanisms in vitro to model nervous system outside of our body using human induced pluripotent stem (iPS) cells. In our body, neurons reach and connect each other to form a functional nervous system. An axon, an extended part of a neuron, can extend for a long range and connect distant regions. Axons extending toward similar regions bind each other to form a nerve tissue. We developed an in vitro system to model a motor nerve tissue in a simple microdevice bearing a microchannel connected to a chamber. An aggregate of motor neurons derived from human iPS cells was placed in the chamber, and the cells extend their axons in to the chamber. The axons spontaneously form a bundle through their innate ability to interact each other, resulting in an axon bundle tissue. We characterized the tissue, and demonstrated that we can evaluate drug efficacy on axon protection.
Microfluidics and Microfabrication for Instrumented Organs-on-a-Chip
by Dr. Vincent Senez, LIMMS/CNRS-IIS UMI2820, SMMiL-E project
This talk will give a short overview of my past research activities in the field of microfabrication and microfluidics and how they support my LIMMS research project aiming at designing instrumented organs-on-a-chip. More precisely I will present how electrical properties of a 3D culture can give information on the viability and proliferation of cancerous cells. It will be illustrated in the context of resistance study for pancreatic cancer.
Role of the blood vessel endothelium in escape from immunity & BioMEMS approaches
by Dr. Fabrice Soncin, LIMMS/CNRS-IIS UMI2820, SMMiL-E project
The endothelium lines the inner face of blood vessels, in direct contact with the circulation. During inflammation, endothelial cells become activated and favor the rolling, arrest, firm adhesion, and extravasation of immune cells from the circulation toward the tissues. This response is vital and its regulation critical and we have shown that the non-activated state of the endothelium depends on endogenous signals (genes, miRNAs) which are constitutively active in endothelial cells in order to maintain their quiescent state in normal conditions. The repression of these signals triggers the activation of the endothelium in the absence of pro-inflammatory stimuli and promotes immune cell adhesion to the endothelium. On the other hand, expression of such factors by cancer cells promotes tumor escape from immunity and favors tumor growth. Our projects aim at developing novel vascular BioMEMS devices in order to study these endothelial regulatory signals.
Marker–free enrichment of rare cancer cells by combining multi-property isolation method
by Dr. Soo Hyeon Kim, The University of Tokyo
Genetic analysis, rather than just counting the number of rare cancer cells, i.e. circulating tumor cells (CTCs), in a peripheral blood has a great potential for the realization of non-invasive biopsy so called “liquid biopsy.” However, a practical problem on the conventional rare cancer cells enrichment is that the isolated target cells are still mixed with numerous residual leukocytes. In this talk, I will introduce a novel marker-free method of CTC enrichment based on size-based Filtration and Immunomagnetic Negative selection followed by Dielectophoretic concentration (CTC-FIND) for direct detection of genetic mutation on rare cancer cells suspended in a whole blood. Highly efficient marker-free cancer cell purification (4.4-log depletion of leukocytes) was achieved with CTC-FIND method by combining two independent isolation methods based on physical (filtration) and biochemical properties (immunomagnetic negative selection). The method showed very high sensitivity of 1 cell/mL on the mutation detection of rare cancer cells spiked in whole blood. In the meanwhile, an efficient single-cell analysis system is required in order to analyze the isolated rare cells to understand cell-to-cell variations. I will also introduce microfluidic device allowing highly efficient single-cell trapping followed by on-chip analysis at the single-cell level with minimal loss of sample (cell capture efficiency of 96%). By combining the CTC-FIND method and the microfluidic device, a highly efficient CTC enrichment and analysis system could be realized, which allows us to understand characteristics of CTCs and to utilize the CTCs for the personalized cancer therapy.
A tumor-on-chip approach to investigate the drug resistance in gastric poorly cohesive carcinoma
by Dr. Deniz Pekin
Gastric poorly cohesive carcinoma is a cancer of epithelial origin characterized by a diffuse distribution of tumor cells. Despite recent advances, more patients are being diagnosed with advanced GCC with an increasing incidence of 400% in the western world. More than 2000 cases are diagnosed in France, majority of which are young adults. These carcinomas may have inherent chemo-resistance creating a controversy on whether a chemotherapeutic regimen should be used. Understanding the pathogenenis of GCC is critical in the treatment and in the improvement of the prognosis of patients. For this regard the cancer cells and the components of the stroma should be taken separately and combined in controlled ratios to assess their role in the development of the disease itself and the mechanisms behind the drug resistance. Such a goal can only be achieved by an interdisciplinary approach combining together the clinical expertise and microtechnologies. The scope of this project is to investigate the drug resistance of the gastric poorly cohesive carcinoma by creating tumor models with highly controllable cellular contents by encapsulating cancer and stroma cells inside emulsion droplets of water-in-oil in order to assess the effect of stroma on the drug resistance. These tumor models will later be developed to be used as patient-on-chip models to test the efficiency of treatment regiments in the preclinical workflow.
Biophysical signature-based cell sorting for the study of drug resistance in lung cancer
by Dr. Donghyuk Kim
Promises from advanced therapies (e.g., targeted and/or immuno-therapies) against lung cancer has been greatly hindered by resistance development in patients; resistance has become one of the major challenges in today’s oncology. Identification of actionable markers for resistance is a key to overcome resistance, which requires profiling of various characteristics from the statistically significant number of cells that give rise of resistance. Microfluidics allows proper handles to manipulate cells in a consistent and reproducible manner providing means to achieve such assessments. The presentation will demonstrate in two scenarios where microfluidics helps answer biologically-inspired questions, and propose a microfluidics-based research that pursues a search for actionable markers in lung cancer resistance.