Figure 2.

Delta‐like homologue 1 (DLK1) protein expression in the first maxillary molar in mice was detected by immunohistochemical analysis. A(a), At PN2,DLK1 was expressed in the ODs, and mildly expressed in a few dental pulp cells near ODs layer. B(b): At PN6, strong positive immunolabelling was observed in the whole ODs layer, and DLK1 was much higher in some DPCs near ODs layer. C(c): At PN6, DLK was not only highly expressed in ODs but also strongly located in a large number of DPCs in DP. Primarily, DLK1 was increasingly expressed in the ODs and DPCs. (IEE: inner enamel epithelium; OD: odontoblast; DP: dental pulp; CL: cervical loop; E: enamel; D: dentin; DPCs: dental pulp cells; white arrows mean DPCs; black arrows mean ODs; A‐C: 200×; a‐c: 400×)