TY - JOUR
T1 - Thermomechanical analysis of freezing-induced cell-fluid-matrix interactions in engineered tissues
AU - Han, Bumsoo
AU - Teo, Ka Yaw
AU - Ghosh, Soham
AU - Dutton, J. Craig
AU - Grinnell, Frederick
N1 - Funding Information:
This research was supported by Grants from the National Institutes of Health/National Institute of Biomedical Imaging and Bioengineering , R01 EB008388 , and the National Science Foundation , CBET-1009465 . The scanning electron microscope images were obtained at the Life Science Microscopy Facility at Purdue University.
PY - 2013/2
Y1 - 2013/2
N2 - Successful cryopreservation of functional engineered tissues (ETs) is significant to tissue engineering and regenerative medicine, but it is extremely challenging to develop a successful protocol because the effects of cryopreservation parameters on the post-thaw functionality of ETs are not well understood. Particularly, the effects on the microstructure of their extracellular matrix (ECM) have not been well studied, which determines many functional properties of the ETs. In this study, we investigated the effects of two key cryopreservation parameters-(i) freezing temperature and corresponding cooling rate; and (ii) the concentration of cryoprotective agent (CPA) on the ECM microstructure as well as the cellular viability. Using dermal equivalent as a model ET and DMSO as a model CPA, freezing-induced spatiotemporal deformation and post-thaw ECM microstructure of ETs was characterized while varying the freezing temperature and DMSO concentrations. The spatial distribution of cellular viability and the cellular actin cytoskeleton was also examined. The results showed that the tissue dilatation increased significantly with reduced freezing temperature (i.e., rapid freezing). A maximum limit of tissue deformation was observed for preservation of ECM microstructure, cell viability and cell-matrix adhesion. The dilatation decreased with the use of DMSO, and a freezing temperature dependent threshold concentration of DMSO was observed. The threshold DMSO concentration increased with lowering freezing temperature. In addition, an analysis was performed to delineate thermodynamic and mechanical components of freezing-induced tissue deformation. The results are discussed to establish a mechanistic understanding of freezing-induced cell-fluid-matrix interaction and phase change behavior within ETs in order to improve cryopreservation of ETs.
AB - Successful cryopreservation of functional engineered tissues (ETs) is significant to tissue engineering and regenerative medicine, but it is extremely challenging to develop a successful protocol because the effects of cryopreservation parameters on the post-thaw functionality of ETs are not well understood. Particularly, the effects on the microstructure of their extracellular matrix (ECM) have not been well studied, which determines many functional properties of the ETs. In this study, we investigated the effects of two key cryopreservation parameters-(i) freezing temperature and corresponding cooling rate; and (ii) the concentration of cryoprotective agent (CPA) on the ECM microstructure as well as the cellular viability. Using dermal equivalent as a model ET and DMSO as a model CPA, freezing-induced spatiotemporal deformation and post-thaw ECM microstructure of ETs was characterized while varying the freezing temperature and DMSO concentrations. The spatial distribution of cellular viability and the cellular actin cytoskeleton was also examined. The results showed that the tissue dilatation increased significantly with reduced freezing temperature (i.e., rapid freezing). A maximum limit of tissue deformation was observed for preservation of ECM microstructure, cell viability and cell-matrix adhesion. The dilatation decreased with the use of DMSO, and a freezing temperature dependent threshold concentration of DMSO was observed. The threshold DMSO concentration increased with lowering freezing temperature. In addition, an analysis was performed to delineate thermodynamic and mechanical components of freezing-induced tissue deformation. The results are discussed to establish a mechanistic understanding of freezing-induced cell-fluid-matrix interaction and phase change behavior within ETs in order to improve cryopreservation of ETs.
KW - Cell image deformetry
KW - Cryopreservation
KW - Cryoprotective agents
KW - Differential scanning calorimetry
KW - Extracellular matrix
KW - Tissue microstructure
UR - http://www.scopus.com/inward/record.url?scp=84870937516&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84870937516&partnerID=8YFLogxK
U2 - 10.1016/j.jmbbm.2012.10.014
DO - 10.1016/j.jmbbm.2012.10.014
M3 - Article
C2 - 23246556
AN - SCOPUS:84870937516
SN - 1751-6161
VL - 18
SP - 67
EP - 80
JO - Journal of the Mechanical Behavior of Biomedical Materials
JF - Journal of the Mechanical Behavior of Biomedical Materials
ER -