Shin Steven S, Liu Chuanju, Chang Eric Y, Carlson Cathy S, Di Cesare Paul E
Musculoskeletal Research Center, Department of Orthopaedic Surgery, NYU-Hospital for Joint Diseases, New York, NY 10003, USA.
J Hand Surg Am. 2004 Sep;29(5):809-14. doi: 10.1016/j.jhsa.2004.02.008.
Dupuytren's fibroblasts, or myofibroblasts, are the primary cell type in Dupuytren's disease. Growth factors play a role in the differentiation of fibroblasts to myofibroblasts. Myofibroblasts are specialized fibroblasts that display morphologic and biochemical features similar to smooth muscle cells. Cytokines, adhesion molecules, and extracellular matrix components are all thought to play a role in myofibroblast transdifferentiation. Recent research has shown that specific cytokines, such as transforming growth factor beta1 (TGF-beta1), can modulate myofibroblast expression. We hypothesize that bone morphogenetic proteins (BMPs) play a role in the modulation of Dupuytren's fibroblasts.
Dupuytren's fibroblasts and normal palmar fascia fibroblasts (control) were analyzed for messenger RNA expression of BMPs (BMP-1, -2, -3, -4, -5, -6, -7, -8, -9, -10 and -11), their receptors (BMPR-IA, BMPR-IB, and BMPR-II), and their antagonists (follistatin and noggin) by reverse-transcription polymerase chain reaction (PCR). Western blot analysis and immunostaining also were used to confirm the differential expression of BMP-4.
With reverse-transcription PCR the expression profile for normal palmar fascia fibroblasts versus Dupuytren's fibroblasts was found to show similar expression of BMP-1 and -11; qualitatively decreased expression of BMP-6, BMP-8, BMPR-IA, BMPR-IB, and BMPR-II in Dupuytren's fibroblasts; and no expression of BMP-4 in Dupuytren's fibroblasts. There was no expression of BMP-2, -3, -5, -7, -9, and -10 in both the control fibroblasts and Dupuytren's fibroblasts. In line with the messenger RNA expression pattern BMP-4 was detected in only the control fibroblasts and not in the Dupuytren's fibroblasts, whereas BMP-8 (chosen for comparison purposes) was detectable in both cell populations. Immunostaining for BMP-8 and BMP-4 confirmed our findings with reverse-transcription PCR and Western blot analysis.
This study reports on the expression of BMPs in Dupuytren's fibroblasts. We characterized the expression of BMPs in both normal palmar fascia fibroblasts and in Dupuytren's fibroblasts through reverse-transcription PCR, Western blot analysis, and immunostaining. The most significant difference in expression profiles was in the expression of BMP-4; that is, BMP-4 was expressed in the normal fibroblasts but not in the Dupuytren's fibroblasts. Whether BMP-4 is necessary and/or sufficient for maintaining a normal palmar fascia fibroblast phenotype is not yet known. Further studies are needed to elucidate the exact role of BMPs, and especially BMP-4, in Dupuytren's fibroblasts.
杜普伊特伦挛缩症中的成纤维细胞，即肌成纤维细胞，是该疾病的主要细胞类型。生长因子在成纤维细胞向肌成纤维细胞的分化过程中发挥作用。肌成纤维细胞是一种特殊的成纤维细胞，具有与平滑肌细胞相似的形态和生化特征。细胞因子、黏附分子和细胞外基质成分均被认为在肌成纤维细胞转分化中起作用。最近的研究表明，特定的细胞因子，如转化生长因子β1（TGF-β1），可调节肌成纤维细胞的表达。我们推测骨形态发生蛋白（BMPs）在杜普伊特伦挛缩症成纤维细胞的调节中起作用。
通过逆转录聚合酶链反应（PCR）分析杜普伊特伦挛缩症成纤维细胞和正常掌腱膜成纤维细胞（对照）中BMPs（BMP-1、-2、-3、-4、-5、-6、-7、-8、-9、-10和-11）、其受体（BMPR-IA、BMPR-IB和BMPR-II）及其拮抗剂（卵泡抑素和头蛋白）的信使RNA表达。蛋白质免疫印迹分析和免疫染色也用于确认BMP-4的差异表达。
通过逆转录PCR发现，正常掌腱膜成纤维细胞与杜普伊特伦挛缩症成纤维细胞的表达谱显示BMP-1和-11表达相似；杜普伊特伦挛缩症成纤维细胞中BMP-6；BMP-8；BMPR-IA；BMPR-IB和BMPR-II表达定性降低；杜普伊特伦挛缩症成纤维细胞中无BMP-4表达。对照成纤维细胞和杜普伊特伦挛缩症成纤维细胞中均无BMP-2、-3、-5、-7、-9和-10表达。与信使RNA表达模式一致，仅在对照成纤维细胞中检测到BMP-4，而在杜普伊特伦挛缩症成纤维细胞中未检测到，而BMP-8（为比较目的选择）在两个细胞群体中均可检测到。BMP-8和BMP-4的免疫染色证实了我们逆转录PCR和蛋白质免疫印迹分析的结果。
本研究报道了BMPs在杜普伊特伦挛缩症成纤维细胞中的表达。我们通过逆转录PCR、蛋白质免疫印迹分析和免疫染色对正常掌腱膜成纤维细胞和杜普伊特伦挛缩症成纤维细胞中BMPs的表达进行了表征。表达谱中最显著的差异在于BMP-4的表达；即，BMP-4在正常成纤维细胞中表达，但在杜普伊特伦挛缩症成纤维细胞中不表达。BMP-4对于维持正常掌腱膜成纤维细胞表型是否必要和/或充分尚不清楚。需要进一步研究以阐明BMPs，尤其是BMP-4在杜普伊特伦挛缩症成纤维细胞中的确切作用。
