Figure 1.

Aggregated hDPSCs undergo apoptosis shortly after implantation

(A) Preparation of implanted tooth scaffold, with a height of 5 mm. (B) Schematic of the tooth transplantation process in the dorsum of athymic nude mice. Tooth scaffolds were filled with aggregated hDPSC. (C) H&E staining shows the regeneration of dental-pulp-like tissue; dp, dental pulp; d, dentin. Scale bars, 100 μm in low-magnification images and 50 μm in high-magnification images. (D) Immunofluorescence analysis shows the expression of odontogenic differentiation markers DSPP and DMP1, with positive staining represented by green and red stains. DSPP, dentin sialophosphoprotein; DMP1, dentin matrix protein 1; d, dentin. Scale bars, 100 μm. (E) TUNEL staining shows the apoptosis ratio of aggregated hDPSCs before transplantation (Ctrl), or 24, 48, or 72 h after transplantation. Scale bars, 100 μm in low-magnification images and 50 μm in high-magnification images; n = 5 per group. (F) Flow cytometry analysis shows the apoptosis ratio of aggregated hDPSC before transplantation (Ctrl), or 24, 48, 72, or 96 h after transplantation. ∗Annexin V (+) and 7-AAD (–) cell ratio compared with Ctrl; ˆannexin V (+) cells ratio compared with Ctrl; n = 3 per group. Data are presented as mean ± SD. Statistical analyses were performed by one-way ANOVA with Tukey’s post hoc test or Welch’s ANOVA with Games-Howell post hoc test. ∗p < 0.05, ∗∗/ˆˆp < 0.01, ∗∗∗p < 0.001; ns, p > 0.05.