Tetsuhiko Teshima

Fluid shear triggers microvilli formation via mechanosensitive activation of TRPV6

Microvilli are cellular membrane protrusions present on differentiated epithelial cells, which can sense and interact with the surrounding fluid environment. Biochemical and genetic approaches have identified a set of factors involved in microvilli formation; however, the underlying extrinsic regulatory mechanism of microvilli formation remains largely unknown. Here we demonstrate that fluid shear stress (FSS), an external mechanical cue, serves as a trigger for microvilli formation in human placental trophoblastic cells. We further reveal that the transient receptor potential, vanilloid family type-6 (TRPV6) calcium ion channel plays a critical role in flow-induced Ca2+ influx and microvilli formation. TRPV6 regulates phosphorylation of Ezrin via a Ca2+-dependent phosphorylation of Akt; this molecular event is necessary for microvillar localization of Ezrin in response to FSS. Our findings provide molecular insight into the microvilli-mediated mechanoresponsive cellular functions, such as epithelial absorption, signal perception and mechanotransduction.

Parylene Mobile Microplates Integrated with an Enzymatic Release for Handling of Single Adherent Cells

An approach for manipulating single adherent cells is developed that is integrated with an enzymatic batch release. This strategy uses an array of releasable microfabricated mobile substrates, termed microplates, formed from a biocompatible polymer, parylene. A parylene microplate array of 10-70 μm in diameter can be formed on an alginate hydrogel sacrificial layer by using a standard photolithographic process. The parylene surfaces are modified with fibronectin to enhance cell attachment, growth, and stretching. To load single cells onto these microplates, cells are initially placed in suspension at an optimized seeding density and are allowed to settle, stretch, and grow on individual microplates. The sacrificial layer underneath the microplate array can be dissolved on a time-scale of several seconds without cytotoxicity. This system allows the inspection of selected single adherent cells. The ability to assess single cells while maintaining their adhesive properties will broaden the examination of a variety of attributes, such as cell shape and cytoskeletal properties.

Liquid-filled tunable lenticular lens

This paper describes a liquid-filled tunable lenticular lens for switching between two-dimensional (2D) and three-dimensional (3D) images in naked-eye 3D displays. Compared with previous 2D/3D switchable displays, this tunable lenticular lens that is directly attached to a smartphone display can project both a 2D image with the original resolution of the smartphone display and a 3D image with high brightness. This lens is simply composed of transparent poly(dimethylsiloxane) (PDMS) microchannels. While the thin top membrane on the microchannels is normally flat to transmit light without deflection for displaying 2D images, applying pressure to the microchannel deforms the membrane to acquire characteristics of lenticular lenses for 3D images. We successfully demonstrate the switching between the 2D and 3D modes. We believe that our lens can be applied as a part of a portable 2D/3D naked-eye 3D display.

Magnetically responsive microflaps reveal cell membrane boundaries from multiple angles

A microflap system to incline adherent cells in the desired orientation is described. Inclination angles of cell-laden microflaps are precisely controlled by the applied magnetic field, enabling us to observe cell-membrane boundaries from multiple angles. This system is equipped with conventional microscopes, allowing clear focused images of cell-membrane boundaries to be obtained with high magnification.

High-Resolution Vertical Observation of Intracellular Structure Using Magnetically Responsive Microplates

A vertical confocal observation system capable of high-resolution observation of intracellular structure is demonstrated. The system consists of magnet-active microplates to rotate, incline, and translate single adherent cells in the applied magnetic field. Appended to conventional confocal microscopes, this system enables high-resolution cross-sectional imaging with single-molecule sensitivity in single scanning.

Integrated Microfluidic System for Size-Based Selection and Trapping of Giant Vesicles

Vesicles composed of phospholipids (liposomes) have attracted interest as artificial cell models and have been widely studied to explore lipid-lipid and lipid-protein interactions. However, the size dispersity of liposomes prepared by conventional methods was a major problem that inhibited their use in high-throughput analyses based on monodisperse liposomes. In this study, we developed an integrative microfluidic device that enables both the size-based selection and trapping of liposomes. This device consists of hydrodynamic selection and trapping channels in series, which made it possible to successfully produce an array of more than 60 monodisperse liposomes from a polydisperse liposome suspension with a narrow size distribution (the coefficient of variation was less than 12%). We successfully observed a size-dependent response of the liposomes to sequential osmotic stimuli, which had not clarified so far, by using this device. Our device will be a powerful tool to facilitate the statistical analysis of liposome dynamics.

Mobile Microplates for Morphological Control and Assembly of Individual Neural Cells

A microfabricated device that enables morphological control and assembly of cultured single neural cells is described. Assembly of morphologically controlled single neural cells allows neuroengineers to design in vitro neural circuits with a single-cell resolution. Compared to conventional cell-patterning techniques, the device allows for the highly precise positioning of neural somas and neurites in a reproducible fashion.

Neural Cells: Mobile Microplates for Morphological Control and Assembly of Individual Neural Cells (Adv. Healthcare Mater. 4/2016)

Individual neural cells on micro-sized plates are morphologically controlled, mobilized, and utilized as building blocks of a neural circuit. On p. 415, S. Takeuchi and co-workers show how the mobile microplate device enables precise positioning of individual neural cell bodies and neurites in a reproducible fashion, which potentially allows neuroengineers to design the geometry of cultured neural circuits (Cover design: Akiko Sato).

Vertical and horizontal confocal imaging of single cells on magnetically handleable microplates

In this study, we purpose the microfabricated system to manipulate single host cells of parasites toward the analysis of invasion at single cell level. We fabricated the microplates made from Parylene and modified the shape and structure of surface by using lithography techniques. This device is able to not only control the shape and morphology of adhering host cells, but also handle them maintaining their adherent property. The ability to manipulate single adherent host cells reveals the unknown triggered key for parasite invasion. This method can be an attractive platform for the manipulation of host cells, the observation of invading microbes and the analysis of interaction between microbe and host cells.

Centrifuge-based dynamic microarray system toward an array of a few amount of sample

In this study, we purpose a centrifuge-based dynamic microarray system (CDM) for trapping micro-sized samples sequentially from only 10 μl of the samples. Our system enables us to make an array of microbeads only with a spin-coater. The air can be introduced to the microchannel to isolate and encapsulate the trapped beads by the specific speed rotation because the microbeads were fixed at the outlet of the trapping spots by the centrifugal force. We optimized rotation speed for trapping with the high trapping yield and successfully controlled sample/solution/air introduction. This device can also release the trapped beads by flowing liquid backward, which allows us to retrieve the microbeads and reuse the device. The presented technology marks an essential step towards a high efficient portable CDM for point-of-care use.