Generation of a Bioengineered Tooth by Using a Three-Dimensional Cell Manipulation Method (Organ Germ Method)

Abstract

The arrangement of cells within a tissue plays an essential role in organogenesis, including tooth development. Organ morphogenesis and physiological functions induced by three-dimensional tissue organization are well known to be regulated by the proper spatiotemporal organization of various signaling molecules, including cytokines, extracellular matrix proteins, and adhesion molecules. Development of a three-dimensional cell manipulation technology to create a bioengineered organ germ, designated as the organ germ method, enabled the generation of a structurally correct and fully functional bioengineered tooth in vivo. This method is expected to be utilized as a valuable technique for analyzing gene and protein functions during organogenesis. Here, we describe protocols for tooth germ reconstitution using the organ germ method and methods for analyzing tooth development in vitro and in vivo.

Functional lacrimal gland regeneration by transplantation of a bioengineered organ germ

“…Nestin- and Ki67-positive stem/progenitor cells capable of repairing interleukin-1-induced inflammation in murine-lacrimal glands41 and cells expressing stem cell markers such as c-kit, ABCG2 and ALDH1 in cultures of human lacrimal gland cells42 have been identified for tissue regeneration using stem cell transplantation. In contrast, we have proposed a novel approach for bioengineered organ replacement to restore organ function by the engraftment of a bioengineered organ germ in vivo 272943. In the present study, we further demonstrated that our organ-germ methods could be applied to not only teeth and hair follicles but also to secretory organs such as lacrimal and harderian glands.…”

“…Single epithelial and mesenchymal cells were precipitated by centrifugation, and the supernatants were removed. The bioengineered gland germs were reconstituted using our previously described 3D cell-manipulation method43. Briefly, mesenchymal cells were injected into collagen drop using micropipette.…”

Lhx8 mediated Wnt and TGFβ pathways in tooth development and regeneration

“…E16.5 tooth germs were harvested per conventional procedures[18, 19]. Briefly, the first mandibular molar tooth germs were dissected from E16.5 mouse embryo with fine forceps under dissection microscope.…”

The junctional epithelium originates from the odontogenic epithelium of an erupted tooth

“…In the present study, we clarified the origin of the JE using a bioengineered tooth germ method2021(Fig. 1a).…”