Department of Dentistry, Faculty of Medical Sciences, University of Kragujevac, Kragujevac, Serbia.
Department of Histology and Embryology, Faculty of Medical Sciences, University of Kragujevac, Kragujevac, Serbia.
Int Endod J. 2022 Jan;55(1):64-78. doi: 10.1111/iej.13638. Epub 2021 Oct 21.
To investigate the influence of strain differences in immune responses on the pathogenesis of experimental periapical lesions in Dark Agouti (DA) and Albino Oxford (AO) inbred strains of rats.
Periapical lesions were induced in male DA and AO rats by pulp exposure of the first mandibular right molars to the oral environment. Animals were killed 21 days after pulp exposure. The mandibular jaws were retrieved and prepared for radiographic, pathohistological, immunohistochemical analysis, real-time PCR and flow cytometry. Blood samples and the supernatant of periapical lesions were collected for measurement of cytokines and oxidative stress marker levels. Statistical analysis was performed using the Kruskal-Wallis H and Mann-Whitney U non-parametric tests or parametric One-Way anova and Independent Samples T-test to determine the differences between groups depending on the normality of the data. A significant difference was considered when p values were <.05.
DA rats developed significantly larger (p < .05) periapical lesions compared to AO rats as confirmed by radiographic and pathohistological analysis. The immunohistochemical staining intensity for CD3 was significantly greater in periapical lesions of DA rats compared to AO rats (p < .05). In DA rats, periapical lesions had a significantly higher (p < .05) percentage of CD3+ cells compared to AO rats. Also, the percentage of INF-γ, IL-17 and IL-10 CD3+CD4+ cells was significantly higher in DA rats (p < .05). DA rats had a significantly higher Th17/Th10 ratio. RT-PCR expression of IL-1β, INF-γ and IL-17 genes was significantly higher in periapical lesions of DA compared to AO rats (p < .05). The receptor activator of nuclear factor kappa-Β ligand/osteoprotegerin ratio was higher in DA compared to AO rats with periapical lesions (p < .05). Systemic levels of TNF-α and IL-6 were significantly higher in DA compared to AO rats (p < .05). Levels of lipid peroxidation measured as thiobarbituric acid reactive substances and reduced glutathione were significantly higher (p < .05) in the supernatant in the periapical lesions of DA rats.
After pulp exposure, DA rats developed much larger periapical lesions compared to AO rats. Genetically determined differences in immunopathology have been demonstrated to be a significant element defining the severity of periapical lesions.
研究免疫反应的应变差异对 Dark Agouti（DA）和 Albino Oxford（AO）近交系大鼠实验性根尖病变发病机制的影响。
通过暴露第一下颌右侧磨牙的牙髓来诱导雄性 DA 和 AO 大鼠的根尖病变，将动物在牙髓暴露后 21 天处死。取出下颌骨并准备进行放射照相、组织病理学、免疫组织化学分析、实时 PCR 和流式细胞术分析。收集根尖病变的血清样本和上清液，以测量细胞因子和氧化应激标志物水平。使用 Kruskal-Wallis H 和 Mann-Whitney U 非参数检验或参数 One-Way ANOVA 和独立样本 T 检验，根据数据的正态性，分析组间的差异。当 p 值<.05 时，认为存在显著差异。
与 AO 大鼠相比，DA 大鼠的根尖病变明显更大（p<.05），这一点得到了放射照相和组织病理学分析的证实。与 AO 大鼠相比，DA 大鼠根尖病变的 CD3 免疫组织化学染色强度明显更高（p<.05）。在 DA 大鼠中，根尖病变的 CD3+细胞比例明显高于 AO 大鼠（p<.05）。此外，DA 大鼠的 INF-γ、IL-17 和 IL-10 CD3+CD4+细胞的百分比明显更高（p<.05）。DA 大鼠的 Th17/Th10 比值明显更高。与 AO 大鼠相比，DA 大鼠根尖病变的 IL-1β、INF-γ 和 IL-17 基因的 RT-PCR 表达明显更高（p<.05）。与 AO 大鼠相比，DA 大鼠的核因子 kappa-B 配体/骨保护素受体比值在根尖病变中更高（p<.05）。与 AO 大鼠相比，DA 大鼠的 TNF-α 和 IL-6 系统水平明显更高（p<.05）。DA 大鼠根尖病变上清液中的丙二醛反应产物和还原型谷胱甘肽的水平明显更高（p<.05）。
在牙髓暴露后，与 AO 大鼠相比，DA 大鼠的根尖病变明显更大。免疫病理学的遗传差异已被证明是决定根尖病变严重程度的重要因素。
