Abstract：
BACKGROUND: Healing the full-thickness skin wounds has remained a challenge. One of the most frequently used grafts for skin regeneration is xenogeneic acellular dermal matrices (ADMs), including bovine ADMs. This study investigated the effect of the source animal age, enzymatic versus non-enzymatic decellularization protocols, and gamma irradiation versus ethylene oxide (EO) sterilization on the scaffold.
METHODS: ADMs were prepared using the dermises of fetal bovine or calf skins. All groups were decellularized through chemical and mechanical methods, unless T-FADM samples, in which an enzymatic step was added to the decellularization protocol. All groups were sterilized with ethylene oxide (EO), except G-FADM which was sterilized using gamma irradiation. The scaffolds were characterized through scanning electron microscopy, differential scanning calorimetry, tensile test, MTT assay, DNA quantification, and real-time PCR. The performance of the ADMs in wound treatment was also evaluated macroscopically and histologically.
RESULTS: All ADMs were effectively decellularized. In comparison to FADM (EO-sterilized fetal ADM), morphological, and mechanical properties of G-FADM, T-FADM, and CADM (EOsterilized calf ADM) were changed to different extents. In addition, the CADM and G-FADM were thermally more stable than the FADM and T-FADM. Although all ADMs were noncytotoxic, the wounds of the FADM, T-FADM, and G-FADM groups were contracted to almost 30.0% of the original area on day 7, significantly faster than the CADM (17.5% ± 1.7) and control (12.2% ± 1.59) groups. However, by day 21, all ADMs were mostly closed except for the untreated group (60.1 ± 1.8).
CONCLUSIONS: Altogether, fetal source and EO-sterilized samples performed better than calf source and gamma-sterilized samples unless in some mechanical properties. There was no added value in using enzymatic treatment during the decellularization process. Our results suggest that the age, decellularization, and sterilization methods of animal source should be selected based on the clinical requirements.
METHODS: ADMs were prepared using the dermises of fetal bovine or calf skins. All groups were decellularized through chemical and mechanical methods, unless T-FADM samples, in which an enzymatic step was added to the decellularization protocol. All groups were sterilized with ethylene oxide (EO), except G-FADM which was sterilized using gamma irradiation. The scaffolds were characterized through scanning electron microscopy, differential scanning calorimetry, tensile test, MTT assay, DNA quantification, and real-time PCR. The performance of the ADMs in wound treatment was also evaluated macroscopically and histologically.
RESULTS: All ADMs were effectively decellularized. In comparison to FADM (EO-sterilized fetal ADM), morphological, and mechanical properties of G-FADM, T-FADM, and CADM (EOsterilized calf ADM) were changed to different extents. In addition, the CADM and G-FADM were thermally more stable than the FADM and T-FADM. Although all ADMs were noncytotoxic, the wounds of the FADM, T-FADM, and G-FADM groups were contracted to almost 30.0% of the original area on day 7, significantly faster than the CADM (17.5% ± 1.7) and control (12.2% ± 1.59) groups. However, by day 21, all ADMs were mostly closed except for the untreated group (60.1 ± 1.8).
CONCLUSIONS: Altogether, fetal source and EO-sterilized samples performed better than calf source and gamma-sterilized samples unless in some mechanical properties. There was no added value in using enzymatic treatment during the decellularization process. Our results suggest that the age, decellularization, and sterilization methods of animal source should be selected based on the clinical requirements.
摘要：
背景：治愈全层皮肤伤口仍然是一个挑战。用于皮肤再生的最常用移植物之一是异种无细胞真皮基质（ADMs），包括牛ADMs。这项研究调查了来源动物年龄的影响，酶促脱细胞与非酶促脱细胞方案，以及支架上的γ辐照与环氧乙烷（EO）灭菌。
方法:使用胎牛或小牛皮的证据制备ADM。所有组均通过化学和机械方法脱细胞，除非T-FADM取样,其中将酶促步骤添加到去细胞化方案中。各组均采用环氧乙烷(EO)灭菌,除了G-FADM使用γ辐照灭菌。通过扫描电子显微镜对支架进行表征，差示扫描量热法,拉伸试验,MTT测定，DNA定量,和实时PCR。还通过宏观和组织学评估了ADM在伤口治疗中的性能。
结果：所有ADM均有效脱细胞。与FADM（EO灭菌胎儿ADM）相比，形态学,G-FADM的力学性能，T-FADM,和CADM（EO无菌小牛ADM）进行了不同程度的改变。此外,CADM和G-FADM比FADM和T-FADM更热稳定。尽管所有ADM都是非细胞毒性的，FADM的伤口,T-FADM,G-FADM组在第7天收缩至原始面积的近30.0％，明显快于CADM（17.5％±1.7）和对照组（12.2％±1.59）。然而,到第21天，除了未治疗组（60.1±1.8）外，所有ADM大部分关闭。
结论：总而言之，除非具有某些机械性能，否则胎儿来源和EO灭菌样品的性能优于小腿来源和γ灭菌样品。在去细胞化过程中使用酶处理没有附加值。我们的结果表明，年龄，去细胞化,应根据临床要求选择动物来源的灭菌方法。
方法:使用胎牛或小牛皮的证据制备ADM。所有组均通过化学和机械方法脱细胞，除非T-FADM取样,其中将酶促步骤添加到去细胞化方案中。各组均采用环氧乙烷(EO)灭菌,除了G-FADM使用γ辐照灭菌。通过扫描电子显微镜对支架进行表征，差示扫描量热法,拉伸试验,MTT测定，DNA定量,和实时PCR。还通过宏观和组织学评估了ADM在伤口治疗中的性能。
结果：所有ADM均有效脱细胞。与FADM（EO灭菌胎儿ADM）相比，形态学,G-FADM的力学性能，T-FADM,和CADM（EO无菌小牛ADM）进行了不同程度的改变。此外,CADM和G-FADM比FADM和T-FADM更热稳定。尽管所有ADM都是非细胞毒性的，FADM的伤口,T-FADM,G-FADM组在第7天收缩至原始面积的近30.0％，明显快于CADM（17.5％±1.7）和对照组（12.2％±1.59）。然而,到第21天，除了未治疗组（60.1±1.8）外，所有ADM大部分关闭。
结论：总而言之，除非具有某些机械性能，否则胎儿来源和EO灭菌样品的性能优于小腿来源和γ灭菌样品。在去细胞化过程中使用酶处理没有附加值。我们的结果表明，年龄，去细胞化,应根据临床要求选择动物来源的灭菌方法。
