Keywords
Tissue Engineering; Cartilage Repair; Chondrogenic Differentiation; Biophysical Stimulation; Pulsed Electromagnetic Fields
Abstract
The tissue engineering is a multidisciplinary field with the aim to repair the tissue combining the use of stem cells and biomaterials, whose activity can be controlled by the addition of signal molecules, such as growth factors or modulated by physical stimuli. Tissue engineering requires two phases: an in vitro phase to develop the construct in culture and an in vivo phase including the surgical implantation of the construct to repair the tissue defect and the outcome evaluation.
It is known that pulsed electromagnetic fields (PEMFs) (1.5 mT, 75Hz) plays several positive effects on cartilage and bone tissues and they are used in orthopedics with benefit for patients.
The rationale for using PEMFs in tissue-engineering techniques for cartilage repair is based on two important findings: [1] the increase in anabolic activity of chondrocytes and cartilage explants exposed to PEMFs and [2] preventing the catabolic effects of inflammation due to surgical trauma at the site lesion itself, thanks to the agonistic activity for the A2A adenosine receptor. More recently, PEMFs have been studied on human Mesenchymal stem cells (hMSCs) and it has been shown that PEMFs can favour chondrogenic differentiation in the presence of an inflammatory microenvironment counteracting the de-differentiating activity of proinflammatory cytokines.
On the basis of these considerations, PEMFs may be useful in promoting the formation of new cartilage in the engineered construct during its preparation in vitro, to protect the construct when surgically implanted in an inflammatory environment and to favor its integration with the surrounding host tissue. However, several gaps have been highlighted from the clinical outcome evaluation and they deserve attention to improve the use of PEMFs as an useful tool for cell-based regeneration of cartilage defects in orthopedics.
Citation
Ongaro A. Biophysical Stimulation with Pulsed Electromagnetic Fields as Innovative Approach for Functional Tissue Engineering of Cartilage. Stem Cell Res. 2016; 2(1): 1004.