This study was aimed to investigate the effects of cGMP xeno-/serum-free medium (XSF, Irvine Scientific) on the properties of human dental pulp stem cells (DPSCs). DPSCs, from passage 2, were cultured in XSF or fetal bovine serum (FBS)-supplemented medium, and sub-cultured up to passage 8. Cumulative population doublings (PDs) and the number of colony-forming-units (CFUs) were determined. qRT-PCR, ELISA, and in vitro assays were used to assess angiogenic capacity. Flow cytometry was used to measure CD73, CD90, and CD105 expression. Differentiation into osteo-, adipo-, and chondrogenic cell lineages was performed. DPSCs showed more elongated morphology, a reduced rate of proliferation at later passages, and lower CFU counts in XSF compared with FBS. Expression of angiogenic factors at the gene and protein levels varied in the two media and with passage number, but cells grown in XSF had more in vitro angiogenic activity. The majority of early and late passage DPSCs cultured in XSF expressed CD73 and CD90. In contrast, the percentage of CD105 positive DPSCs in XSF medium was significantly lower with increased passage whereas the majority of cells cultured in FBS were CD105 positive. Switching XSF-cultured DPSCs to medium supplemented with human serum restored the expression of CD105. The tri-lineage differentiation of DPSCs cultured under XSF and FBS conditions was similar. We showed that despite reduced CD105 expression levels, DPSCs expanded in XSF medium maintained a functional MSC phenotype. Furthermore, restoration of CD105 expression is likely to occur upon in vivo transplantation, when cells are exposed to human serum.

中文翻译：

---

评估在 cGMP 异种/无血清培养基中培养的牙髓干细胞的生长、干性和血管生成特性

本研究旨在研究 cGMP 无异种/无血清培养基（XSF，Irvine Scientific）对人牙髓干细胞 (DPSC) 特性的影响。DPSCs，从第 2 代开始，在 XSF 或胎牛血清 (FBS) 补充培养基中培养，并传代培养至第 8 代。 确定累积种群倍增 (PD) 和集落形成单位 (CFU) 的数量. qRT-PCR、ELISA 和体外测定用于评估血管生成能力。流式细胞术用于测量 CD73、CD90 和 CD105 的表达。分化为骨细胞、脂肪细胞和软骨细胞谱系。与 FBS 相比，DPSCs 显示出更细长的形态，后期传代的增殖率降低，XSF 中的 CFU 计数更低。血管生成因子在基因和蛋白质水平上的表达在两种培养基和传代数中有所不同，但在 XSF 中生长的细胞具有更多的体外血管生成活性。在 XSF 中培养的大多数早期和晚期 DPSC 表达 CD73 和 CD90。相比之下，XSF 培养基中 CD105 阳性 DPSC 的百分比随着传代的增加而显着降低，而在 FBS 中培养的大多数细胞是 CD105 阳性的。将 XSF 培养的 DPSCs 转换为补充有人血清的培养基可恢复 CD105 的表达。在 XSF 和 FBS 条件下培养的 DPSCs 的三系分化相似。我们发现，尽管 CD105 表达水平降低，但在 XSF 培养基中扩增的 DPSCs 保持了功能性 MSC 表型。此外，体内移植后可能会恢复 CD105 表达，