3D Printing of Osteocytes for Application in Biological Environment

The biological environment maintains vital functions by responding to the surrounding changes inside and outside the body in association with various kinds of substances including nucleic acids and proteins. In addition, dynamic environmental changes, such as pH fluctuations and changes in oxygen concentration due to cellular activities, are regulated by molecular mediators, leading to hierarchical tissue and organ function. In recent years, bio-3D （three-dimensional） printing technology for assembling organs from cells has evolved dramatically. In particular, bone tissue regulates its function by constructing a highly oriented micro-organization of the bone matrix through the action of multicellular systems. The creation of mini bone organs that enable the expression of highly regulated bone functions is expected by building up a three-dimensional structure with the interconnection of heterologous types of cells. Indeed, bone function is regulated by interactions with cells based on the responses of osteocytes （stress-sensitive cells in the bone matrix） to in vivo environmental stimuli. The aim of this study is to control cellular functions in the biological environment by controlling the osteocyte arrangement using the bioprinting technique. Drawing living cells at the single-cell level and constructing cell-cell interactions are expected to lead to the elucidation of mechanisms for highly regulated bone functions and also functional artificial organ development.