Alginate, as a natural polysaccharide hydrogel, is promising for tissue engineering and cell therapeutic strategies. The construction and properties of alginate scaffolds can be modified by divalent cations as cross-linkers during polymerization. The aim of this study was to investigate the viability and chondrogenic capacity of human Wharton’s jelly-derived mesenchymal stem cells (WJ-MSCs) immobilized on alginate capsules in the presence of BaCl₂ or CaCl₂. In this study, cell viability was evaluated by MTT assay and FDA/PI staining at 1, 10, and 21 days after encapsulation in two groups of calcium alginate (CA) and barium alginate (BA) microcapsules. The alginate microcapsules were stained by Safranin-O to evaluate newly synthesized glycosaminoglycans after 21 days of chondrogenic differentiation. The presence of Collagen-II was also assessed by the immunohistochemistry method. The stability of BA microcapsules was higher than the CA microcapsules. In FDA/PI staining and MTT test, the viability of the WJ-MSCs encapsulated in CA was considerably higher than the BA-encapsulated cells. Also, in the CA microcapsules, the differentiation ability of WJ-MSCs into the chondroblast-like cells was obviously increased. Immuno-staining of collagen-II and Safranin-O staining in the WJ-MSCs encapsulated in the CA was considerably higher than the BA-encapsulated cells. The results of this study showed that a three-dimensional CA culture system has the potential to create a small and suitable environment for the growth and chondrogenic differentiation of the WJ-MSCs.

海藻酸盐作为一种天然多糖水凝胶，有望用于组织工程和细胞治疗策略。藻酸盐支架的结构和性质可以在聚合过程中通过二价阳离子作为交联剂来改变。本研究的目的是研究在 BaCl ₂或 CaCl _{2存在下固定在藻酸盐胶囊上的人类沃顿氏胶衍生的间充质干细胞 (WJ-MSCs) 的活力和成软骨能力。}. 在本研究中，在两组海藻酸钙 (CA) 和海藻酸钡 (BA) 微胶囊封装后 1、10 和 21 天，通过 MTT 测定和 FDA/PI 染色评估细胞活力。用番红-O 对藻酸盐微胶囊进行染色，以评估软骨分化 21 天后新合成的糖胺聚糖。还通过免疫组织化学方法评估胶原蛋白-II 的存在。BA微囊的稳定性高于CA微囊。在 FDA/PI 染色和 MTT 测试中，封装在 CA 中的 WJ-MSCs 的活力明显高于封装 BA 的细胞。此外，在CA微囊中，WJ-MSCs向成软骨细胞样细胞的分化能力明显增强。封装在 CA 中的 WJ-MSC 中胶原蛋白-II 和番红-O 染色的免疫染色显着高于 BA 封装的细胞。本研究结果表明，三维 CA 培养系统有可能为 WJ-MSCs 的生长和成软骨分化创造一个小而合适的环境。