Characterization of Mesenchymal Stromal Cells Derived from Ovine Dental Pulp

Résumé

Osteoarthritis (OA) is the most common degenerative disease of synovial joints. It is a global public health challenge, and its burden constantly increases with overall ageing of the population. The absence of therapeutics to efficiently prevent, reverse or cure OA is an opportunity to explore emerging therapeutic strategies. An encouraging approach in stem cell-based regenerative medicine is the administration of mesenchymal stromal cell (also known as mesenchymal stem cell or MSCs) that can be isolated from adult tissue such as dental pulp. To assess preclinically potential of such therapy, animal models of OA are required, a widely used model is the sheep. In order to exploit future stem cell therapy in OA ovine models, a thorough characterization of the dental pulp-isolated stem cells should be carried out, this includes several key questions as; Which incisors contain the largest amount of pulp and at what age the pulp volume is maximal? Once dental pulp is extracted; is it possible to enrich and expand those cells in culture? Do these cells show properties and biomarkers of human-equivalent MSCs?
Using CT scan imaging, we showed that sheep has the highest quantity of dental pulp in central incisors between 2- and 3-year-old. Pulp cells could be extracted from ovine dental pulp (hypothesized to be oDPSCs) and expanded in culture. As point of comparison, fibroblasts extracted from ovine dermis were in parallel cultured in standard medium (herein, referred as ovine Dermal Fibroblasts (oDFs)). Both cell types were characterized using the same pipeline of analysis, mostly based on ISCT (International Society for Cell Therapy) criteria for human MSCs and including gene expression profile, surface antigen expression, multipotency capacity, and specific methylation patterns. oDPSCs and oDFs did show some differences in mRNA profile where ITGA11 and MYH11 seemed to be good markers for positive selection of oDPSCs.
However, most ISCT markers tested were similarly expressed between oDPSCs and oDFs (CD90, CD105, CD44). oDPSCs showed chondrogenic and adipogenic differentiation potential but no osteogenic potential, while oDFs showed slight chondrogenic and osteogenic differentiation but no adipogenic differentiation. Neither surface markers analysis (CD90, CD73 and CD45) or methylation pattern (CpG island of oCIDEC, oASAM, oSERPINB5) showed difference between oDPSCs and oDFs. In conclusion, this study showed slight differences between oDPSCs and oDFs, meaning that cell types as cultured in our experimental conditions were phenotypically close. ISCT markers did not allow discrimination between both cell types.

la date de réponse	janv. 2022
langue originale	Anglais
L'institution diplômante	Universite de Namur
Superviseur	Jean-Michel Vandeweerd (Promoteur), Charles Nicaise (Copromoteur) & Fanny Hontoir (Copromoteur)