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Effects of gamma radiation sterilization on the structural and biological properties of decellularized corneal xenografts.

ABSTRACT: To address the shortcomings associated with corneal transplants, substantial efforts have been focused on developing new modalities such as xenotransplantion. Xenogeneic corneas are anatomically and biomechanically similar to the human cornea, yet their applications require prior decellularization to remove the antigenic components to avoid rejection. In the context of bringing decellularized corneas into clinical use, sterilization is a crucial step that determines the success of the transplantation. Well-standardized sterilization methods, such as gamma irradiation (GI), have been applied to decellularized porcine corneas (DPC) to avoid graft-associated infections in human recipients. However, little is known about the effect of GI on decellularized corneal xenografts. Here, we evaluated the radiation effect on the ultrastructure, optical, mechanical and biological properties of DPC. Transmission electron microscopy revealed that gamma irradiated decellularized porcine cornea (G-DPC) preserved its structural integrity. Moreover, the radiation did not reduce the optical properties of the tissue. Neither DPC nor G-DPC led to further activation of complement system compared to native porcine cornea when exposed to plasma. Although, DPC were mechanically comparable to the native tissue, GI increased the mechanical strength, tissue hydrophobicity and resistance to enzymatic degradation. Despite these changes, human corneal epithelial, stromal, endothelial and hybrid neuroblastoma cells grew and differentiated on DPC and G-DPC. Thus, GI may achieve effective tissue sterilization without affecting critical properties that are essential for corneal transplant survival.

SUBMITTER: Islam MM

PROVIDER: S-EPMC7043233 | biostudies-literature | 2019 Sep

REPOSITORIES: biostudies-literature

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Effects of gamma radiation sterilization on the structural and biological properties of decellularized corneal xenografts.

Islam Mohammad Mirazul MM Sharifi Roholah R Mamodaly Shamina S Islam Rakibul R Nahra Daniel D Abusamra Dina B DB Hui Pui Chuen PC Adibnia Yashar Y Goulamaly Mehdi M Paschalis Eleftherios I EI Cruzat Andrea A Kong Jing J Nilsson Per H PH Argüeso Pablo P Mollnes Tom Eirik TE Chodosh James J Dohlman Claes H CH Gonzalez-Andrades Miguel M

Acta biomaterialia 20190705

To address the shortcomings associated with corneal transplants, substantial efforts have been focused on developing new modalities such as xenotransplantion. Xenogeneic corneas are anatomically and biomechanically similar to the human cornea, yet their applications require prior decellularization to remove the antigenic components to avoid rejection. In the context of bringing decellularized corneas into clinical use, sterilization is a crucial step that determines the success of the transplant ...[more]

PMID: 31284096

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Dataset Information

Effects of gamma radiation sterilization on the structural and biological properties of decellularized corneal xenografts.

Publications

Effects of gamma radiation sterilization on the structural and biological properties of decellularized corneal xenografts.

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