Macroporous scaffolds associated with cells to construct a hybrid biomaterial for bone tissue engineering.

Cell Culture Laboratory, School of Dentistry of Ribeirao Preto, University of Sao Paulo, Av. do Cafe s/n 14040-904, Ribeirao Preto, SP, Brazil.
Expert Review of Medical Devices (Impact Factor: 2.43). 12/2008; 5(6):719-28. DOI: 10.1586/17434440.5.6.719
Source: PubMed

ABSTRACT Bone tissue has the ability to heal without a scar and to remodel, which promotes three basic functions: locomotion, protection of internal organs and mineral homeostasis. Although bone regeneration is highly efficient, some clinical situations - such as large bone defects - require specific treatments in order to promote bone healing. Allogenic or autologous bone grafts have been used in these procedures with limited success and, based on this, bone tissue-engineering approaches have been investigated extensively. Tissue engineering has been defined as the application of principles and techniques of the life sciences and engineering to the design, modification and growth of living tissues using biomaterials, cells and growth factors, alone or in combination. The association of cells with porous scaffolds to produce 3D hybrid osteogenic constructs is a common subject in bone tissue-engineering research and will be the focus of this review. We will present some aspects of bone biology, the cells and scaffolds used to engineer bone, and techniques to fabricate the hybrid biomaterial.

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    ABSTRACT: Stem cells have emerged as important players in the generation and maintenance of many tissues. However, the accurate in vitro simulation of the native stem cell niche remains difficult due at least in part to the lack of a comprehensive definition of the critical factors of the stem cell niche based on in vivo models. Three-dimensional (3D) cell culture systems have allowed the development of useful models for investigating stem cell physiology particularly with respect to their ability to sense and generate mechanical force in response to their surrounding environment. We review the use of 3D culture systems for stem cell culture and discuss the relationship between stem cells and 3D growth matrices including the roles of the extracellular matrix, scaffolds, soluble factors, cell-cell interactions and shear stress effects within this environment. We also discuss the potential for novel methods that mimic the native stem cell niche in vitro as well as the current associated challenges.
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