Changes of CD90 expression and immunoreactive cell localisation in rat dental pulp after cavity preparation

Abstract

CD90 expression and immunoreactive cell localisation in rat dental pulp cells after cavity preparation was investigated. Cavity preparation was performed on the maxillary first molar of 8-week-old Wistar rats (n = 36), and immunohistochemistry and quantitative real-time PCR were performed. CD90-immunoreactivity was observed among subodontoblastic cells in the control group. One day after cavity preparation, the CD90-immunoreactivity disappeared under the cavity area. While CD90-immunoreactivity was faint after 3 days, the re-arrangement of odontoblasts was detected in contact with dentine. After 5 days, the odontoblasts were observed beneath the dentine, and CD90-immunoreactive cells were localised under the odontoblast layer. Immunofluorescence showed co-localisation of CD90 and nestin was detected after 3 days. After 5 days, CD90-immunoreactivity increased at the subodontoblastic layer. mRNA expression of CD90 and DSPP decreased after cavity preparation, and gradually recovered (P < 0.01). These results suggest that CD90-immunoreactive cells in the subodontoblastic layer contribute to regeneration of odontoblast and subodontoblastic layers following cavity preparation.

Isolation and cultivation as well as in situ identification of MSCs from equine dental pulp and periodontal ligament

“…Inside the dental pulp, these cells were mainly found in the subodontoblastic layer, which is also described for rat by Hosoya et al (6). This might support the theory that undifferentiated cells, which can differentiate toward odontoblasts, are provided by the subodontoblastic layer (37,38). There was a remarkably strong signal of odontoblasts, even inside their processes, which has not been reported yet.…”

Histological analysis for pulp mineralisation after severe intrusive luxation of immature molars in rats

“…This study preliminarily detected the changes in stem cell markers in dental pulp tissue and found that CD90‐immunoreactive cells were distributed in the sub‐odontoblastic layer, which was close to the odontoblasts and pre‐dentin, but were not related to post‐traumatic dental pulp osteogenesis, suggesting that they might be related to dentin development. Other studies have also shown that CD90‐immunoreactive cells are related to reparative dentin formation in molars and continuous dentin development in mouse incisors 30–32 . Although CD146 immunoreacted with cells around the osteoid tissue, it was highly expressed in the vascular endothelial cells and kept stable until the process of osteogenesis finished.…”

“…Other studies have also shown that CD90-immunoreactive cells are related to reparative dentin formation in molars and continuous dentin development in mouse incisors. [30][31][32] Although CD146 immunoreacted with cells around the osteoid tissue, it was highly expressed in the vascular endothelial cells and kept stable until the process of osteogenesis finished. This finding indicated that CD146-positive cells might have differentiated into vascular endothelial cells in the traumatised pulps, but not into osteoblasts.…”