Kramer J, Böhrnsen F, Schlenke P, Rohwedel J
Department of Medical Molecular Biology, University of Lübeck, Campus Lübeck, Lübeck, Germany.
Transplant Proc. 2006 Apr;38(3):762-5. doi: 10.1016/j.transproceed.2006.02.023.
The regenerative capacity of cartilage is limited. Transplantation methods used to treat cartilage lesions are based mainly on primary cultures of chondrocytes, which dedifferentiate during cultivation in vitro and lose their functional properties. Stem cells are considered as an alternative source to generate cells for two reasons: first, they can almost indefinitely divide in culture, and second, they are able to differentiate into various mature cell types. Herein, we asked the question whether chondrocytes could be differentiated from mouse embryonic stem (ES) cells to a state suitable for regenerative use. When cultivated as embryoid bodies (EBs), murine ES cells differentiate into mesenchymal progenitor cells, which progressively develop into mature, hypertrophic chondrocytes and transdifferentiate into calcifying cells recapitulating all of the cellular processes of chondrogenesis. Chondrocytes isolated from EBs exhibit a high regenerative capacity. They dedifferentiate initially in culture, but later reexpress stable characteristics of mature chondrocytes. However, in cultures of chondrocytes isolated from EBs, additional mesenchymal cell types can be observed. Mesenchymal stem (MS) cells from bone marrow have already been used in tissue engineering settings. We compared the chondrogenic differentiation of MS and ES cells.
软骨的再生能力有限。用于治疗软骨损伤的移植方法主要基于软骨细胞的原代培养，而软骨细胞在体外培养过程中会去分化并丧失其功能特性。干细胞被视为生成细胞的另一种来源，原因有二：其一，它们在培养中几乎可以无限分裂；其二，它们能够分化为各种成熟细胞类型。在此，我们探讨了软骨细胞是否可以从小鼠胚胎干细胞（ES细胞）分化为适合再生用途的状态。当作为胚状体（EBs）培养时，小鼠ES细胞分化为间充质祖细胞，后者逐渐发育为成熟的肥大软骨细胞，并转分化为钙化细胞，重现软骨形成的所有细胞过程。从EBs分离出的软骨细胞具有很高的再生能力。它们最初在培养中去分化，但随后会重新表达成熟软骨细胞的稳定特征。然而，在从EBs分离出的软骨细胞培养物中，可以观察到其他间充质细胞类型。来自骨髓的间充质干细胞（MS细胞）已被用于组织工程领域。我们比较了MS细胞和ES细胞的软骨形成分化情况。
