Published online Apr 26, 2022. doi: 10.4252/wjsc.v14.i4.287
Peer-review started: March 28, 2021
First decision: May 12, 2021
Revised: May 19, 2021
Accepted: April 21, 2022
Article in press: April 21, 2022
Published online: April 26, 2022
Processing time: 393 Days and 16.6 Hours
Mesenchymal stem cells (MSC) effects on tissue regeneration are mainly mediated by their secreted substances (secretome), inducing their paracrine activity. This Conditioned medium (CM), including soluble factors (proteins, nucleic acids, lipids) and extracellular vesicles is emerging as a potential alternative to cell therapy. However, the manufacturing of CM suffers from variable procedures and protocols leading to varying results between studies. Besides, there is no well-defined optimized procedure targeting specific applications in regenerative medicine.
To focus on conditioned medium produced from dental MSC (DMSC-CM), we reviewed the current parameters and manufacturing protocols, in order to propose a standardization and optimization of these manufacturing procedures.
We have selected all publications investigating the effects of dental MSC secretome in in vitro and in vivo models of tissue regeneration, in accordance with the PRISMA guidelines.
A total of 351 results were identified. And based on the inclusion criteria described above, 118 unique articles were included in the systematic review. DMSC-CM production was considered at three stages: before CM recovery (cell sources for CM), during CM production (culture conditions) and after production (CM treatment).
No clear consensus could be recovered as evidence-based methods, but we were able to describe the most commonly used protocols: donors under 30 years of age, dental pulp stem cells and exfoliated deciduous tooth stem cells with cell passage between 1 and 5, at a confluence of 70% to 80%. CM were often collected during 48 h, and stored at -80 °C. It is important to point out that the preconditioning environment had a significant impact on DMSC-CM content and efficiency.
Core Tip: Dental Mesenchymal stem cells (DMSC) effects on tissue regeneration are highly mediated by their secreted substances [conditioned medium (CM)] such as soluble factors and extracellular vesicles. The manufacturing of CM products suffers from variable procedures and protocols leading to different results between studies. Focusing on CM produced from DMSC (DMSC-CM), we reviewed the current parameters and manufacturing protocols, aiming to facilitate the standardization and optimization of manufacturing procedures, in accordance with PRISMA guideline. No clear consensus could be recovered as evidence-based methods, but it clearly appeared that the preconditioning environment had a significant impact on DMSC-CM content and efficiency.