Estudo das propriedades resistivas e viscoelasticas em modelo experimental: descelularização, congelamento/descongelamento e radiação

Abstract

Ling bioengineering based on decellularized scaffolds is a potential alternative to organ transplantation. The decellularization aims to break the integrity of the cells and remove cell contents from the organ through the use of enzymatic detergents, maintaining the three-dimensional structure of the extracellular matrix. Freezing and thawing is a procedure applied in the decellularization process and organs storage and may produce changes in the mechanical properties of the lung scaffold, reducing the bioartificial organ performance. Sterilization by gamma radiation is the procedure most commonly used in surgical materials and instruments for clinical application, such as grafts, due to the high penetration of photons in the irradiated matter. The aim of this study was to determine the effects of freezing/thawing and gamma radiation on the mechanical properties of decellularized lungs, as well as during the decellularization process, under physiological pressure-volume regime associated with normal ventilation. It was observed, in mechanical properties of the lung during decellularization, that the initial and final values of resistance and elastance showed no significant differences. The mechanical properties of acellular lung measured before and after submission to freezing/thawing showed a slight increase in the values of elastance. Regarding the gamma radiation, significant increases of resistance and elastance values, in both irradiated and non- frozen frozen groups, was observed. We can conclude that the decellularization by detergent sodium dodecyl sulfate and the use of the freezing/thawing cycles showed no changes that would impair the mechanical performance in their ventilatory lung function. However, the effects of gamma radiation on the structure of the extracellular matrix showed considerable changes on ventilatory parameters.