Key Laboratory of Veterinary Biological Engineering and Technology of Ministry of Agriculture, Institute of Veterinary Medicine, Jiangsu Academy of Agricultural Sciences, Nanjing, China; National Center for Engineering Research of Veterinary Bio-products, Jiangsu Academy of Agricultural Sciences, Nanjing, China; College of Veterinary Medicine, Qingdao Agriculture University, Qingdao, China.
Key Laboratory of Veterinary Biological Engineering and Technology of Ministry of Agriculture, Institute of Veterinary Medicine, Jiangsu Academy of Agricultural Sciences, Nanjing, China; National Center for Engineering Research of Veterinary Bio-products, Jiangsu Academy of Agricultural Sciences, Nanjing, China.
Microb Pathog. 2021 May;154:104829. doi: 10.1016/j.micpath.2021.104829. Epub 2021 Mar 13.
Mycoplasma synoviae (MS) infection causes infectious synovitis and arthritis with hyperplasia of synovial cells in the chicken joint. However, its mechanism is unknown. We used primary chicken synovial fibroblast (CSF) as the research object to study the role of MS in the proliferation of MS-infected CSF and determine the mechanisms involved. Using integrated transcriptomic and proteomic analyses of the interaction between CSF and MS, we screened a proliferation-regulated factor, serum amyloid A (SAA), that may regulate proliferation of MS-infected CSF. SAA appears to be associated with MS-induced CSF proliferation. To study the role of SAA in MS-induced CSF proliferation, a eukaryotic expression vector overexpressing SAA and a small interfering RNA (siRNA) targeting Saa were constructed to manipulate the expression of SAA. Cell proliferation and apoptosis were detected via cell counting kit-8 (CCK-8), 5-Ethynyl-2'-deoxyuridine (EdU), or terminal deoxyribonucleotidyl transferase-mediated dUTP nick-dnd labeling (TUNEL) assays, respectively. Western blot analysis was used to examine the protein expression level of SAA, cyclin E1, and cyclin-dependent kinase 2 (CDK2). In vitro, MS significantly promoted the proliferation of CSF and increased the production of SAA. Overexpression of SAA accelerated the proliferative ability of CSF, whereas knockdown of SAA depressed the proliferative ability of CSF. A TUNEL assay indicated that MS did not induce apoptosis. Silencing of SAA suppressed the expression of cyclin E1 and CDK2. These results suggest that MS may upregulate the expression of SAA, accelerate the cell cycle, and promote proliferation of CSF.
滑液支原体（MS）感染可引起感染性滑膜炎和关节炎，导致鸡关节滑膜细胞增生。然而，其机制尚不清楚。我们以原代鸡滑膜成纤维细胞（CSF）为研究对象，研究 MS 在感染 CSF 细胞增殖中的作用，并确定其涉及的机制。通过对 CSF 与 MS 相互作用的综合转录组学和蛋白质组学分析，我们筛选出一个增殖调节因子，血清淀粉样蛋白 A（SAA），它可能调节 MS 感染的 CSF 增殖。SAA 似乎与 MS 诱导的 CSF 增殖有关。为了研究 SAA 在 MS 诱导的 CSF 增殖中的作用，构建了一个过表达 SAA 的真核表达载体和一个针对 Saa 的小干扰 RNA（siRNA），以操纵 SAA 的表达。通过细胞计数试剂盒-8（CCK-8）、5-乙炔基-2'-脱氧尿苷（EdU）或末端脱氧核苷酸转移酶介导的 dUTP 缺口末端标记（TUNEL）检测分别检测细胞增殖和凋亡。Western blot 分析用于检测 SAA、细胞周期蛋白 E1 和细胞周期蛋白依赖性激酶 2（CDK2）的蛋白表达水平。在体外，MS 显著促进 CSF 的增殖并增加 SAA 的产生。SAA 的过表达加速了 CSF 的增殖能力，而 SAA 的敲低则抑制了 CSF 的增殖能力。TUNEL 检测表明 MS 不会诱导细胞凋亡。SAA 的沉默抑制了细胞周期蛋白 E1 和 CDK2 的表达。这些结果表明，MS 可能上调 SAA 的表达，加速细胞周期进程，促进 CSF 的增殖。
