Articles by Yuji Nashimoto in JoVE
Perfusable Vascular Network with a Tissue Model in a Microfluidic Device Yuji Nashimoto1, Yukako Teraoka1, Ramin Banan Sadeghian1, Akiko Nakamasu2, Yuichiro Arima3, Sanshiro Hanada3, Hidetoshi Kotera1, Koichi Nishiyama3, Takashi Miura2, Ryuji Yokokawa1 1Department of Micro Engineering, Kyoto University, 2Graduate School of Medical Sciences, Kyushu University, 3International Research Center for Medical Sciences (IRCMS), Kumamoto University The protocol describes how to engineer a perfusable vascular network in a spheroid. The spheroid's surrounding microenvironment is devised to induce angiogenesis and connect the spheroid to the microchannels in a microfluidic device. The method allows the perfusion of the spheroid, which is a long-awaited technique in three-dimensional cultures.
Other articles by Yuji Nashimoto on PubMed
Continuous Collection and Simultaneous Detection of Picoliter Volume of Nucleic Acid Samples Using a Mille-feuille Probe Analytical and Bioanalytical Chemistry. | Pubmed ID: 27838750 Investigation of the positional heterogeneity of messenger RNA (mRNA) expression in tissues requires a technology that facilitates analysis of mRNA expression in the selected single cells. We developed a mille-feuille probe (MP) that allows the lamination of the aqueous and organic phases in a nanopipette under voltage control. The MP was used for continuous collection of different nucleic acid samples and sequential evaluation of gene expression with mRNA barcoding tags. First, we found that the aqueous phases could be laminated into five individual layers and separated by the plugs of the organic phases in a nanopipette when the salt (THATPBCl) concentration in the organic phase was 100 mM. Second, the aspiration rate of the MP was stabilized and the velocity of the aqueous phase in the MP was lowered at higher THATPBCl concentrations in the organic phase. This was because the force during ingression of the aqueous phase into the organic - phase-filled nanopipette induced an electro-osmotic flow between the inside wall of the nanopipette and THATPBCl in the organic phase. Third, inclusion of mRNA barcoding tags in the MP facilitated complementary DNA construction and sequential analysis of gene expression. This technique has potential to be applicable to RNA sequencing from different cell samples across the life sciences. Graphical abstract We developed a mille-feuille probe (MP) that allows the lamination of the aqueous and organic phases in a nanopipette under voltage control.
Integrating Perfusable Vascular Networks with a Three-dimensional Tissue in a Microfluidic Device Integrative Biology : Quantitative Biosciences from Nano to Macro. | Pubmed ID: 28561127 Creating vascular networks in tissues is crucial for tissue engineering. Although recent studies have demonstrated the formation of vessel-like structures in a tissue model, long-term culture is still challenging due to the lack of active perfusion in vascular networks. Here, we present a method to create a three-dimensional cellular spheroid with a perfusable vascular network in a microfluidic device. By the definition of the cellular interaction between human lung fibroblasts (hLFs) in a spheroid and human umbilical vein endothelial cells (HUVECs) in microchannels, angiogenic sprouts were induced from microchannels toward the spheroid; the sprouts reached the vessel-like structures in a spheroid to form a continuous lumen. We demonstrated that the vascular network could administer biological substances to the interior of the spheroid. As cell density in the spheroid is similar to that of a tissue, the perfusable vasculature model opens up new possibilities for a long-term tissue culture in vitro.