Williamson Kate Ann, Lee Katie Joanna, Humphreys William James Edward, Comerford Eithne Josephine Veronica, Clegg Peter David, Canty-Laird Elizabeth Gail
Department of Musculoskeletal Biology, Institute of Ageing and Chronic Disease, Leahurst Campus, University of Liverpool, Chester High Road, Neston, CH64 7TE, United Kingdom.
J Orthop Res. 2015 Jun;33(6):849-58. doi: 10.1002/jor.22891.
The aim of this study was to characterize stem and progenitor cell populations from the equine superficial digital flexor tendon, an energy-storing tendon with similarities to the human Achilles tendon, which is frequently injured. Using published methods for the isolation of tendon-derived stem/progenitor cells by low-density plating we found that isolated cells possessed clonogenicity but were unable to fully differentiate towards mesenchymal lineages using trilineage differentiation assays. In particular, adipogenic differentiation appeared to be restricted, as assessed by Oil Red O staining of stem/progenitor cells cultured in adipogenic medium. We then assessed whether differential adhesion to fibronectin substrates could be used to isolate a population of cells with broader differentiation potential. However we found little difference in the stem and tenogenic gene expression profile of these cells as compared to tenocytes, although the expression of thrombospondin-4 was significantly reduced in hypoxic conditions. Tendon-derived stem/progenitor cells isolated by differential adhesion to fibronectin had a similar differentiation potential to cells isolated by low density plating, and when grown in either normoxic or hypoxic conditions. In summary, we have found a restricted differentiation potential of cells isolated from the equine superficial digital flexor tendon despite evidence for stem/progenitor-like characteristics.
本研究的目的是对马的指浅屈肌腱中的干细胞和祖细胞群体进行特征描述。指浅屈肌腱是一种储能肌腱，与人类经常受伤的跟腱有相似之处。我们采用已发表的通过低密度接种来分离肌腱来源的干细胞/祖细胞的方法，发现分离出的细胞具有克隆形成能力，但在三系分化试验中无法完全向间充质谱系分化。特别是，通过对在成脂培养基中培养的干细胞/祖细胞进行油红O染色评估，发现成脂分化似乎受到限制。然后，我们评估了对纤连蛋白底物的差异黏附是否可用于分离具有更广泛分化潜能的细胞群体。然而，我们发现与腱细胞相比，这些细胞的干细胞和肌腱生成基因表达谱几乎没有差异，尽管在缺氧条件下血小板反应蛋白-4的表达显著降低。通过对纤连蛋白的差异黏附分离出的肌腱来源的干细胞/祖细胞，与通过低密度接种分离出的细胞在常氧或缺氧条件下生长时具有相似的分化潜能。总之，尽管有证据表明存在干细胞/祖细胞样特征，但我们发现从马指浅屈肌腱分离出的细胞分化潜能有限。
