Stomatology Hospital, School of Stomatology, Zhejiang University School of Medicine, Zhejiang Provincial Clinical Research Center of Oral Diseases, Key Laboratory of Oral Biomedical Research of Zhejiang Province, Cancer Center of Zhejiang University, Hangzhou, China.
J Dent Res. 2023 Oct;102(11):1199-1209. doi: 10.1177/00220345231176520. Epub 2023 Aug 9.
The long-term success rate of dental implants can be improved by establishing a favorable biological sealing with a high-quality epithelial attachment. The application of mesenchymal stem cells (MSCs) holds promise for facilitating the soft tissue integration around implants, but the molecular mechanism is still unclear and the general application of MSC sheet for soft tissue integration is also relatively unexplored. We found that gingival tissue-derived MSC (GMSC) sheet treatment significantly promoted the expression of hemidesmosome (HD)-related genes and proteins in gingival epithelial cells (GECs). The formation of HDs played a key role in strengthening peri-implant epithelium (PIE) sealing. Further, high-throughput transcriptome sequencing showed that GMSC sheet significantly upregulated the PI3K/AKT pathway, confirming that cell adhesion and HD expression in GECs were regulated by GMSC sheet. We observed that the expression of transcription factor CREB3L2 in GECs was downregulated. After treatment with PI3K pathway inhibitor LY294002, CREB3L2 messenger RNA and protein expression levels were upregulated. Further experiments showed that overexpression or knockdown of CREB3L2 could significantly inhibit or promote HD-related genes and proteins, respectively. We confirmed that CREB3L2 was a transcription factor downstream of the PI3K/AKT pathway and participated in the formation of HDs regulated by GMSC sheet. Finally, through the establishment of early implant placement model in rats, we clarified the molecular function of CREB3L2 in PIE sealing as a mechanical transmission molecule in GECs. The application of GMSC sheet-implant complex could enhance the formation of HDs at the implant-PIE interface and decrease the penetration distance of horseradish peroxidase between the implant and PIE. Meanwhile, GMSC sheet reduced the length of CREB3L2 protein expression on PIE. These findings elucidate the potential function and molecular mechanism of MSC sheet regulating the epithelial sealing around implants, providing new insights and ideas for the application of stem cell therapy in regenerative medicine.
种植体的长期成功率可以通过建立良好的生物学密封和高质量的上皮附着来提高。间充质干细胞（MSCs）的应用有望促进种植体周围软组织的整合，但分子机制尚不清楚，MSC 片在软组织整合中的一般应用也相对未知。我们发现牙龈组织来源的 MSC（GMSC）片治疗显著促进了牙龈上皮细胞（GEC）中半桥粒（HD）相关基因和蛋白的表达。HD 的形成在加强种植体周围上皮（PIE）密封中起着关键作用。此外，高通量转录组测序显示，GMSC 片显著上调了 PI3K/AKT 通路，证实 GEC 中的细胞黏附和 HD 表达受 GMSC 片调节。我们观察到 GEC 中转录因子 CREB3L2 的表达下调。用 PI3K 通路抑制剂 LY294002 处理后，CREB3L2 信使 RNA 和蛋白表达水平上调。进一步的实验表明，CREB3L2 的过表达或敲低分别显著抑制或促进 HD 相关基因和蛋白的表达。我们证实 CREB3L2 是 PI3K/AKT 通路下游的转录因子，参与 GMSC 片调节的 HD 形成。最后，通过建立大鼠早期种植体放置模型，我们阐明了 CREB3L2 在 PIE 密封中的分子功能作为 GEC 中机械传递分子。GMSC 片-种植体复合物的应用可以增强种植体-PIE 界面上 HD 的形成，并减少 HRP 穿过种植体和 PIE 的穿透距离。同时，GMSC 片减少了 PIE 上 CREB3L2 蛋白表达的长度。这些发现阐明了 MSC 片调节种植体周围上皮密封的潜在功能和分子机制，为干细胞治疗在再生医学中的应用提供了新的见解和思路。
