Copyright ©The Author(s) 2020. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Stem Cells. Sep 26, 2020; 12(9): 1023-1031
Published online Sep 26, 2020. doi: 10.4252/wjsc.v12.i9.1023
Mass acquisition of human periodontal ligament stem cells
Hidefumi Maeda
Hidefumi Maeda, Department of Endodontology and Operative Dentistry, Division of Oral Rehabilitation, Faculty of Dental Science, Kyushu University, 3-1-1 Maidashi, Fukuoka 8128582, Japan
Supported by Japan Society for the Promotion of Science, No. JP17H01598.
Conflict-of-interest statement: There is no conflict of interest.
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See:
Corresponding author: Hidefumi Maeda, DDS, PhD, Chairman, Professor, Department of Endodontology and Operative Dentistry, Division of Oral Rehabilitation, Faculty of Dental Science, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 8128582, Japan.
Received: May 19, 2020
Peer-review started: May 19, 2020
First decision: June 5, 2020
Revised: June 8, 2020
Accepted: August 1, 2020
Article in press: August 1, 2020
Published online: September 26, 2020

The periodontal ligament (PDL) is an essential fibrous tissue for tooth retention in the alveolar bone socket. PDL tissue further functions to cushion occlusal force, maintain alveolar bone height, allow orthodontic tooth movement, and connect tooth roots with bone. Severe periodontitis, deep caries, and trauma cause irreversible damage to this tissue, eventually leading to tooth loss through the destruction of tooth retention. Many patients suffer from these diseases worldwide, and its prevalence increases with age. To address this issue, regenerative medicine for damaged PDL tissue as well as the surrounding tissues has been extensively investigated regarding the potential and effectiveness of stem cells, scaffolds, and cytokines as well as their combined applications. In particular, PDL stem cells (PDLSCs) have been well studied. In this review, I discuss comprehensive studies on PDLSCs performed in vivo and contemporary reports focusing on the acquisition of large numbers of PDLSCs for therapeutic applications because of the very small number of PDLSCs available in vivo.

Keywords: Induced pluripotent stem cells, Mesoderm specific transcript, Periodontal ligament stem cells, Periodontal tissue, Regenerative medicine, Semaphorin 3A

Core tip: For patients with severe periodontitis, deep caries, and trauma, which can lead to tooth loss, the development of highly effective regenerative therapies for severely damaged periodontal tissue is an urgent concern. As one possible method to address this issue, cell-based therapy using periodontal ligament stem cells (PDLSCs) shows great promise. However, the number of PDLSCs present in vivo is too small for implementation of this method, and PDLSC isolation requires patients to undergo invasive surgery. In this review, ways to acquire large numbers of PDLSCs and advances in periodontal regenerative therapy during the past two decades are summarized.