Departments of Surgery and of Biomedicine, University Hospital Basel, Basel, Switzerland.
Tissue Eng Part A. 2012 Feb;18(3-4):362-72. doi: 10.1089/ten.TEA.2011.0234. Epub 2011 Nov 4.
Previous studies showed that human nasal chondrocytes (HNC) exhibit higher proliferation and chondrogenic capacity as compared to human articular chondrocytes (HAC). To consider HNC as a relevant alternative cell source for the repair of articular cartilage defects it is necessary to test how these cells react when exposed to environmental factors typical of an injured joint. We thus aimed this study at investigating the responses of HNC and HAC to exposure to interleukin (IL)-1β and low oxygen. For this purpose HAC and HNC harvested from the same donors (N=5) were expanded in vitro and then cultured in pellets or collagen-based scaffolds at standard (19%) or low oxygen (5%) conditions. Resulting tissues were analyzed after a short (3 days) exposure to IL-1β, mimicking the initially inflammatory implantation site, or following a recovery time (1 or 2 weeks for pellets and scaffolds, respectively). After IL-1β treatment, constructs generated by both HAC and HNC displayed a transient loss of GAG (up to 21.8% and 36.8%, respectively) and, consistently, an increased production of metalloproteases (MMP)-1 and -13. Collagen type II and the cryptic fragment of aggrecan (DIPEN), both evaluated immunohistochemically, displayed a trend consistent with GAG and MMPs production. HNC-based constructs exhibited a more efficient recovery upon IL-1β withdrawal, resulting in a higher accumulation of GAG (up to 2.6-fold) compared to the corresponding HAC-based tissues. On the other hand, HAC displayed a positive response to low oxygen culture, while HNC were only slightly affected by oxygen percentage. Collectively, under the conditions tested mimicking the postsurgery articular environment, HNC retained a tissue-forming capacity, similar or even better than HAC. These results represent a step forward in validating HNC as a cell source for cartilage tissue engineering strategies.
先前的研究表明，与关节软骨细胞（HAC）相比，人鼻软骨细胞（HNC）表现出更高的增殖和软骨生成能力。为了将 HNC 视为修复关节软骨缺损的相关替代细胞来源，有必要测试这些细胞在暴露于受伤关节特有的环境因素时的反应。因此，我们旨在研究 HNC 和 HAC 对白细胞介素（IL）-1β和低氧的反应。为此，从同一供体（N=5）中收获 HAC 和 HNC 并在体外进行扩增，然后在标准（19%）或低氧（5%）条件下在球体或基于胶原的支架中培养。在短暂（3 天）暴露于模拟最初炎症植入部位的 IL-1β后或在恢复时间（分别为 1 或 2 周）后，分析由此产生的组织。在 IL-1β 处理后，来自 HAC 和 HNC 的构建体均显示出 GAG 的短暂丧失（分别为 21.8%和 36.8%），并且一致地增加了金属蛋白酶（MMP）-1 和 -13 的产生。用免疫组化评估的 II 型胶原和聚集蛋白聚糖的隐蔽片段（DIPEN）均显示出与 GAG 和 MMP 产生一致的趋势。在 IL-1β 撤回后，基于 HNC 的构建体表现出更有效的恢复，导致 GAG 的积累增加（高达 2.6 倍），与相应的基于 HAC 的组织相比。另一方面，HAC 对低氧培养显示出阳性反应，而 HNC 仅受氧百分比的轻微影响。总体而言，在所测试的条件下模拟手术后关节环境，HNC 保持了组织形成能力，与 HAC 相似甚至更好。这些结果代表了验证 HNC 作为软骨组织工程策略的细胞来源的重要一步。
