title: Mechanical properties of acellular mouse lungs after sterilization by gamma irradiation.
abstract: Lung bioengineering using decellularized organ scaffolds is a potential alternative for lung transplantation. Clinical application will require donor scaffold sterilization. As gamma-irradiation is a conventional method for sterilizing tissue preparations for clinical application, the aim of this study was to evaluate the effects of lung scaffold sterilization by gamma irradiation on the mechanical properties of the acellular lung when subjected to the artificial ventilation maneuvers typical within bioreactors. Twenty-six mouse lungs were decellularized by a sodium dodecyl sulfate detergent protocol. Eight lungs were used as controls and 18 of them were submitted to a 31kGy gamma irradiation sterilization process (9 kept frozen in dry ice and 9 at room temperature). Mechanical properties of acellular lungs were measured before and after irradiation. Lung resistance (RL) and elastance (EL) were computed by linear regression fitting of recorded signals during mechanical ventilation (tracheal pressure, flow and volume). Static (Est) and dynamic (Edyn) elastances were obtained by the end-inspiratory occlusion method. After irradiation lungs presented higher values of resistance and elastance than before irradiation: RL increased by 41.1% (room temperature irradiation) and 32.8% (frozen irradiation) and EL increased by 41.8% (room temperature irradiation) and 31.8% (frozen irradiation). Similar increases were induced by irradiation in Est and Edyn. Scanning electron microscopy showed slight structural changes after irradiation, particularly those kept frozen. Sterilization by gamma irradiation at a conventional dose to ensure sterilization modifies acellular lung mechanics, with potential implications for lung bioengineering.
authors.affiliation: Unitat de Biofísica i Bioenginyeria, Facultat de Medicina, Universitat de Barcelona, Barcelona, Spain; CIBER de Enfermedades Respiratorias, Bunyola, Spain; Institut Investigacions Biomediques August Pi Sunyer, Barcelona, Spain.
authors.forename: Juan J
authors.initials: JJ
authors.lastname: Uriarte
authors.affiliation: Unitat de Biofísica i Bioenginyeria, Facultat de Medicina, Universitat de Barcelona, Barcelona, Spain.
authors.forename: Paula N
authors.initials: PN
authors.lastname: Nonaka
authors.affiliation: Unitat de Biofísica i Bioenginyeria, Facultat de Medicina, Universitat de Barcelona, Barcelona, Spain; CIBER de Enfermedades Respiratorias, Bunyola, Spain; Institut de Bioenginyeria de Catalunya, Barcelona, Spain.
authors.forename: Noelia
authors.initials: N
authors.lastname: Campillo
authors.affiliation: Unitat de Biofísica i Bioenginyeria, Facultat de Medicina, Universitat de Barcelona, Barcelona, Spain.
authors.forename: Renata K
authors.initials: RK
authors.lastname: Palma
authors.affiliation: Unitat de Biofísica i Bioenginyeria, Facultat de Medicina, Universitat de Barcelona, Barcelona, Spain; CIBER de Enfermedades Respiratorias, Bunyola, Spain; Institut Investigacions Biomediques August Pi Sunyer, Barcelona, Spain.
authors.forename: Esther
authors.initials: E
authors.lastname: Melo
authors.affiliation: Master׳s and Doctoral Degree Programs in Rehabilitation Sciences, Nove de Julho University, Sao Paulo, Brazil.
authors.forename: Luis V F
authors.initials: LVF
authors.lastname: de Oliveira
authors.affiliation: Unitat de Biofísica i Bioenginyeria, Facultat de Medicina, Universitat de Barcelona, Barcelona, Spain; CIBER de Enfermedades Respiratorias, Bunyola, Spain; Institut de Bioenginyeria de Catalunya, Barcelona, Spain.
authors.forename: Daniel
authors.initials: D
authors.lastname: Navajas
authors.affiliation: Unitat de Biofísica i Bioenginyeria, Facultat de Medicina, Universitat de Barcelona, Barcelona, Spain; CIBER de Enfermedades Respiratorias, Bunyola, Spain; Institut Investigacions Biomediques August Pi Sunyer, Barcelona, Spain. Electronic address: rfarre@ub.edu.
authors.forename: Ramon
authors.initials: R
authors.lastname: Farré
mesh_terms: D000818:Animals; D001696:Biomechanical Phenomena; D004307:Dose-Response Relationship, Radiation; D005720:Gamma Rays; D008168:Lung / Q000166:cytology* / Q000528:radiation effects; D008297:Male; D055595:Mechanical Phenomena; D051379:Mice; D013242:Sterilization
keywords: Gamma irradiation; Lung bioengineering; Lung decellularization; Organ scaffold; Pulmonary mechanics