Yuka Yamagishi

Microfluidic perfusion culture system for multilayer artery tissue models

We described an assembly technique and perfusion culture system for constructing artery tissue models. This technique differed from previous studies in that it does not require a solid biodegradable scaffold; therefore, using sheet-like tissues, this technique allowed the facile fabrication of tubular tissues can be used as model. The fabricated artery tissue models had a multilayer structure. The assembly technique and perfusion culture system were applicable to many different sizes of fabricated arteries. The shape of the fabricated artery tissue models was maintained by the perfusion culture system; furthermore, the system reproduced the in vivo environment and allowed mechanical stimulation of the arteries. The multilayer structure of the artery tissue model was observed using fluorescent dyes. The equivalent Youngs modulus was measured by applying internal pressure to the multilayer tubular tissues. The aim of this study was to determine whether fabricated artery tissue models maintained their mechanical properties with developing. We demonstrated both the rapid fabrication of multilayer tubular tissues that can be used as model arteries and the measurement of their equivalent Youngs modulus in a suitable perfusion culture environment.

Fabrication of engineered tubular tissue for small blood vessels via three-dimensional cellular assembly and organization ex vivo

Although there is a great need for suitable vascular replacements in clinical practice, much progress needs to be made toward the development of a fully functional tissue-engineered construct. We propose a fabrication method of engineered tubular tissue for small blood vessels via a layer-by-layer cellular assembly technique using mouse smooth muscle cells, the construction of a poly-(l-lactide-co-ε-caprolactone) (PLCL) scaffold, and integration in a microfluidic perfusion culture system. The cylindrical PLCL scaffold is incised, expanded, and its surface is laminated with the cell layers. The construct confirms into tubular structures due to residual stress imposed by the cylindrical PLCL scaffold. The perfusion culture system allows simulation of static, perfusion (laminar flow), and perfusion with pulsatile pressure (Pulsatile flow) conditions in which mimicking the in vivo environments. The aim of this evaluation was to determine whether fabricated tubular tissue models developed their mechanical properties. The cellular response to hemodynamic stimulus imposed by the dynamic culture system is monitored through expression analysis of fibrillin-1 and fibrillin-2, elastin and smooth muscle myosin heavy chains isoforms transcription factors, which play an important role in tissue elastogenesis. Among the available materials for small blood vessel construction, these cellular hybrid vascular scaffolds hold much potential due to controllability of the mechanical properties of synthetic polymers and biocompatibility of integrated cellular components.

Circulatory culture system for elastic fiber development of tissue-engineered blood vessels

We proposed a fabrication technique of tubular tissues as an artery and the circulatory culture system for evaluating the development mechanisms of them. The tubular tissues were 2-6 mm in diameter, using a poly (L-lactide-co-ipusironn-caprolactone) (PLCL) scaffold. They consisted of the cell membranes and the PLCL scaffolds. Moreover, these tubular tissues had a mechanical property of artery because of the PLCL scaffolds. We successfully integrated them to the circulatory culture system. After that, we can evaluate the elastic fiber development of the tubular tissues with the mechanical stimulus utilizing the developed circulatory culture system.

Evaluation of cellular behavior in a multilayer structured tubular tissue with the PLCL scaffold

We proposed a 3D assembly technique of small-diameter blood vessels using a PLCL (poly (L-lactide-co-ε-caprolactone)) scaffold. The technique uses a residual stress of PLCL scaffolds to fabricate a multilayer structured tubular tissue, and gives a tissue mechanical property which blood vessels originally have. In the future, we try to test the circulatory culture system in order to investigate whether the tissue-engineered structure maintains the equivalent mechanical property as the human blood vessel. In this work, we demonstrated that fabricated tissues could attach on the inside of tubular PLCL scaffold in the appropriate conditions.

Circulatory culture system for multilayer-structured tubular tissues

We proposed a 3D assembly technique and a circulatory culture system. The technique gives multilayer-structured tubular tissues for blood vessel models. By the circulatory culture system, this study was aimed to determine whether the tissue-engineered tubular models maintain the normally mechanical property as the development and function. In this work, we were able to fabricate tubular tissues from multilayered tissues rapidly in the suitable conditions and circularly culture the fabricated multilayer-structured tubular tissues.

Fabrication of multilayer structured tubular tissue using water transfer printing

We proposed a 3D assembly technique using water transfer printing to fabricate a multilayer structured tubular tissue. This study was aimed to determine whether the tissue-engineered tubular structure maintains the normally mechanical property as the development and function by the artificial circulatory system. In this work, we demonstrated that fabricated tissues could rapidly assemble into aligned tubular tissue in the appropriate geometrical conditions using engineering approaches. This technique does not require a solid biodegradable scaffold. Therefore, this approach presents the simple and rapid method to create through the exploitation of the intrinsic potential of cells to assemble fabricated tissues into functional 3D tissues in a suitable tubular tissue environment. The described technique is applicable to many different cell types and can be used to engineer tissue constructs of user-defined size and shape with micro-scale control of the cellular organization, which could form the basis for constructing 3D engineered tissues with a hollow tubular tissue in vitro.