Bioreactors for Tissue Engineering: Focus on Mechanical Constraints. A Comparative Review

Abstract

Considering the current techniques in cell culture, the stimulation of cellular proliferation and the formation of bidimensional tissues such as skin are widely performed in academic and industrial research laboratories. However, the formation of cohesive, organized, and functional tissues by three-dimensional (3D) cell culture is complex. A suitable environment is required, which is achieved and maintained in a specific bioreactor, a device that reproduces the physiological environment (including biochemical and mechanical functions) specific to the tissue that is to be regenerated. Bioreactors can also be used to apply mechanical constraints during maturation of the regenerating tissue for studying and understanding the mechanical factors influencing tissue regeneration. In this work, the main types of bioreactors used for tissue engineering and regeneration, as well as their most common applications, were reviewed and compared. The importance of the mechanical properties applied to the scaffolds and the regenerating constructs has been often neglected. This review focused on the influence of mechanical stresses and strains during the culture period that leads to the final mechanical properties of the construct.

Fabrication, mechanical and in vivo performance of polycaprolactone/tricalcium phosphate composite scaffolds

“…Three of the main elements required to engineer tissue are (i) a scaffold, (ii) cells and (iii) a dynamic environment in which the cell-scaffold construct are conditioned [6][7][8]. In bone tissue engineering, current techniques employ the use of porous, 3D, biodegradable, biocompatible, and bioresorbable scaffolds, which act as temporary platforms for initial cell attachment and subsequent tissue formation.…”

Design and Characterization of a Rotating Bed System Bioreactor for Tissue Engineering Applications

“…Variables that need to be controlled include temperature, pH, pO 2 , and medium flow rate. Mechanical stimulation is also known to be an important factor for tissue generation (2,3,10). The type of mechanical stimulation and the intensity depend on the cell type or construct that has to be generated.…”

Biomechanics and tissue engineering

“…Despite all these results, most of the gathered mechanotransduction knowledge has been used only for the development of bioreactors to optimize in vitro tissue formation in scaffolds [29]. Rotating bioreactors have been designed to increase mass transfer by inducing dynamic flow conditions in culture [30].…”