Chuen Fu Sai, Chuk Cheuk Yau, Ping Wong Yim, Nar Wong Wan, Kim Hung Leung, Ming Chan Kai
Department of Orthopaedics and Traumatology, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, New Territories, Hong Kong.
J Histochem Cytochem. 2004 Sep;52(9):1151-7. doi: 10.1369/jhc.3A6232.2004.
Cells in tendons are conventionally identified as elongated tenocytes and ovoid tenoblasts, but specific markers for these cells are not available. The roles and interplay of these cells in tendon growth, remodeling, and healing are not well established. Therefore, we proposed to characterize these cells with respect to cell turnover, extracellular matrix metabolism, and expression of growth factors. Here we examined 14 healthy human patellar tendon samples for the expression of various proteins in tenocytes and tenoblasts, which were identified as elongated tendon cells and ovoid tendon cells, respectively. Matrix metalloproteinase 1 (MMP1), procollagen type I (procol I), heat shock protein 47 (hsp47), bone morphogenetic protein 12 (BMP12), 13 (BMP13), and transforming growth factor beta1 (TGFbeta1) were detected by immunohistochemistry (IHC). An image analysis of the IHC staining for proliferation cell nuclear antigen (PCNA) and apoptotic cells was performed to determine the proliferation index and the apoptosis index in elongated and ovoid tendon cells. The ovoid tendon cells expressed higher levels of procol I, hsp47, MMP1, BMP12, BMP13, and TGFbeta1 than the elongated tendon cells. Both the proliferation index and the apoptosis index of ovoid tendon cells were higher than those of the elongated tendon cells. The results suggested that ovoid tendon cells, conventionally recognized as tenoblasts, were more active in matrix remodeling. The expression of BMP 12, BMP13 and TGFbeta1 might be associated with the different cellular activities of tenoblasts and tenocytes.
传统上，肌腱中的细胞被识别为细长的腱细胞和卵圆形的成腱细胞，但这些细胞的特异性标志物尚未确定。这些细胞在肌腱生长、重塑和愈合中的作用及相互作用尚未完全明确。因此，我们提议从细胞更新、细胞外基质代谢和生长因子表达方面对这些细胞进行表征。在此，我们检测了14份健康人髌腱样本中腱细胞和成腱细胞中各种蛋白质的表达，其中腱细胞和成腱细胞分别被识别为细长的肌腱细胞和卵圆形的肌腱细胞。通过免疫组织化学（IHC）检测基质金属蛋白酶1（MMP1）、I型前胶原（procol I）、热休克蛋白47（hsp47）、骨形态发生蛋白12（BMP12）、13（BMP13）和转化生长因子β1（TGFβ1）。对增殖细胞核抗原（PCNA）和凋亡细胞的IHC染色进行图像分析，以确定细长和卵圆形肌腱细胞中的增殖指数和凋亡指数。卵圆形肌腱细胞比细长肌腱细胞表达更高水平的procol I、hsp47、MMP1、BMP12、BMP13和TGFβ1。卵圆形肌腱细胞的增殖指数和凋亡指数均高于细长肌腱细胞。结果表明，传统上被认为是成腱细胞的卵圆形肌腱细胞在基质重塑中更活跃。BMP 12、BMP13和TGFβ1的表达可能与成腱细胞和腱细胞不同的细胞活性有关。
