Naslov
Defining a Visual Marker of Progenitor Cells within the Periodontium

Autori
Roguljić, Hrvoje ; Matthews, Brya ; Lacombe, Melissa ; Kalajzić, Ivo.

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
Journal of bone and mineral research / ASBMR (ur.). - / - , 2012

Skup
ASBMR Annual Meeting 2012

Mjesto i datum
Minneapolis (MN), Sjedinjene Američke Države, 14.10.2012. - 18.10.2012

Vrsta sudjelovanja
Poster

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
progenitor cells; periodontium; osteoblasts

Sažetak
The periodontium is the tissue supporting the teeth including cementum, periodontal ligament (PDL) and alveolar bone. In periodontal disease, which is a major cause of tooth loss in adults, the periodontium is inflamed and cementoblasts, PDL fibroblasts and osteoblasts are affected. We have previously identified a periodontal tissue progenitor cell that resides in perivascular areas and expresses GFP under the control of the smooth muscle alpha actin (αSMA) promoter (SMA-GFP). The aim of this study is to identify and trace periodontal progenitor cells in vivo. We have generated an αSMA promoter-driven and tamoxifen inducible Cre mouse (αSMA-CreERT2) that in combination with a Rosa-tomato reporter (SMACre/Tomato) labels a defined cell population. We aimed to examine expansion and localization of these progenitor cells during normal growth and after periodontal injury. To trace these progenitors during normal growth, tamoxifen was administered to 3-week-old SMACre/Tomato mice on two consecutive days to label cells, and histology was performed on the second molar in mandibles after 2 and 17 days. At day 2 a small population of cells in the PDL were labeled. This population expanded by day 17, particularly in the apical region and the tension side of the root. To detect transition of SMACre/tomato labeled cells into mature phenotype we utilized a Col2.3GFP transgene. Following treatment with tamoxifen we detected a small number of SMACre/Tomato/Col2.3GFP-expressing cells by day 17. Using a cell ablation model (Col2.3TK mice) we have established an in vivo injury model. Administration of ganciclovir (GCV) results in the death of cells that express the TK gene and undergo division. SMACre/Tomato/Col2.3TK mice were treated with GCV for 16 days then SMACre-expressing cells were labeled with tamoxifen. 21 days later mice treated with GCV showed remodeling of the apical root and adjacent alveolar bone. We observed an expansion of tomato-labeled cells in the apical root region of the PDL in the GCV-treated mice compared to the untreated controls. In summary, the SMACre transgene labels a small population of cells in the PDL. These cells show expansion and differentiation into mature cells during growth, and increased expansion following cell ablation. This population of cells may represent the source of progenitors that give rise to a number of mature lineages within the periodontium that could assist tissue regeneration in periodontal disease.

Izvorni jezik
Engleski

Znanstvena područja
Temeljne medicinske znanosti

POVEZANOST RADA