Effects of mycophenolic acid on human fibroblast proliferation, migration and adhesion in vitro and in vivo. Homo sapiens

Mycophenolic acid (MPA) is a potent inhibitor of the inosine monophosphate dehydrogenase and commonly used as an immunosuppressive drug in transplantation. MPA inhibits proliferation of both T- and B-lymphocytes by guansoin depletion. Since fibroblasts rely on the de novo synthesis of guanosin nucleotides, it is assumed that MPA interacts with fibroblasts causing an increased frequency of wound healing problems. We show a downregulation of the cytoskeletal proteins actin, vinculin and tubulin in human dermal fibroblasts exposed to pharmacologic doses of MPA using microarray technology and western blot. This reduction in protein content is accompanied by a substantial derangement of the cytoskeleton in MPA-treated fibroblasts as documented by confocal microscopy. The dysfunctional fibroblast growth was validated by scratch test documenting impaired migrational capacity. The results of the cultured dermal fibroblasts were applied to skin biopsies of renal transplant recipients. Skin biopsies of patients treated with MPA expressed less tubulin and actin as compared to control biopsies which could explain potential wound healing problems post transplantation. The perspective of MPA-induced cytoskeletal dysfunction may go beyond wound healing disturbances and has potential beneficial effects on (renal) allografts with respect to scarring. Keywords: Timecourse and MPA and/or Guanosin response Overall design: Human fibroblast are treated with Guanin and or Mycophenolic Acid (MPA). Samples were taken at different timepoints (20min, 1h, 12h,36h). Samples were amplified and hybridised against amplified RNA of Control human fibroblasts in dye-swaps to Human Oligo arrays. For GPR file names with _1, the test sample is labeled with Cy3. For GPR file names with _1, the test sample is labeled with Cy3.

麦考酚酸（Mycophenolic acid，MPA）是一种强效的次黄嘌呤单核苷酸脱氢酶抑制剂，临床常用于器官移植术后的免疫抑制治疗。MPA通过耗竭鸟苷抑制T、B淋巴细胞的增殖。由于成纤维细胞依赖鸟苷核苷酸的从头合成通路，因此推测MPA可作用于成纤维细胞，升高术后伤口愈合并发症的发生风险。本研究借助微阵列技术与蛋白质印迹法（Western Blot），证实经治疗剂量MPA处理的人类皮肤成纤维细胞中，细胞骨架蛋白肌动蛋白、黏着斑蛋白与微管蛋白的表达均出现下调。共聚焦显微镜成像结果显示，MPA处理后的成纤维细胞细胞骨架结构发生显著紊乱，与上述蛋白含量的降低相伴随。划痕实验证实成纤维细胞生长功能异常，其迁移能力受损。本研究将体外培养皮肤成纤维细胞的实验结果，拓展应用至肾移植受者的皮肤活检标本分析。与对照组活检标本相比，接受MPA治疗的患者皮肤活检标本中微管蛋白与肌动蛋白的表达水平更低，这可解释移植术后潜在的伤口愈合并发症。MPA诱导的细胞骨架功能异常，其影响或不止于伤口愈合障碍，在瘢痕形成层面，或对（肾）同种异体移植物产生潜在的有益作用。关键词：时间进程、MPA及/或鸟苷应答 整体实验设计：将人类成纤维细胞分别用鸟苷、麦考酚酸（MPA）或二者联合处理。分别于20min、1h、12h、36h四个时间点采集样本。将样本扩增后的RNA与对照组人类成纤维细胞的扩增RNA进行双色染料互换杂交，随后与Human Oligo微阵列芯片进行杂交。对于带_1后缀的GPR文件，测试样本以Cy3荧光标记。对于带_1后缀的GPR文件，测试样本以Cy3荧光标记。