Expression of p75(NGFR), a Proliferative and Basal Cell Marker, in the Buccal Mucosa Epithelium during Re-epithelialization.
We investigated the expression of p75(NGFR), a proliferative and basal cell marker, in the mouse buccal mucosa epithelium during wound healing in order to elucidate the role of epithelial stem cells. Epithelial defects were generated in the epithelium of the buccal mucosa of 6-week-old mice using CO2 laser irradiation. BrdU was immediately administered to mice following laser irradiation. They were then sacrificed after 1, 3, 7, and 14 days. Paraffin sections were prepared and the irradiated areas were analyzed using immunohistochemistry with anti-p75(NGFR), BrdU, PCNA, and CK14 antibodies. During re-epithelialization, PCNA (-)/p75(NGFR) (+) cells extended to the wound, which then closed, whereas PCNA (+)/p75(NGFR) (+) cells were not observed at the edge of the wound. In addition, p75(NGFR) (-)/CK14 (+), which reflected the presence of post-mitotic differentiating cells, was observed in the supra-basal layers of the extended epithelium. BrdU (+)/p75(NGFR) (+), which reflected the presence of epithelial stem cells, was detected sparsely in buccal basal epithelial cells after healing, and disappeared after 7 days. These results suggest that p75(NGFR) (+) keratinocytes are localized in the basal layer, which contains oral epithelial stem cells, and retain the ability to proliferate in order to regenerate the buccal mucosal epithelium.
Department of Oral and Maxillofacial Surgery, Tokyo Dental College , Chiba, Japan.
Akihiro
A
Ishii
Department of Endodontics and Clinical Cariology, Tokyo Dental College , Tokyo, Japan.
Takashi
T
Muramatsu
Division in Anatomy and Developmental Biology, Department of Oral Biology, Research Center for Orofacial Hard Tissue Regeneration, Brain Korea 21 Project, Yonsei University College of Dentistry , Seodaemun-Gu, Seoul, Republic of Korea.
Jong-Min
JM
Lee
Department of Ophthalmology, Ichikawa General Hospital, Tokyo Dental College , Chiba, Japan ; Cornea Center, Ichikawa General Hospital, Tokyo Dental College , Chiba, Japan.
Kazunari
K
Higa
Department of Ophthalmology, Ichikawa General Hospital, Tokyo Dental College , Chiba, Japan ; Cornea Center, Ichikawa General Hospital, Tokyo Dental College , Chiba, Japan.
Naoshi
N
Shinozaki
Division in Anatomy and Developmental Biology, Department of Oral Biology, Research Center for Orofacial Hard Tissue Regeneration, Brain Korea 21 Project, Yonsei University College of Dentistry , Seodaemun-Gu, Seoul, Republic of Korea.
Han-Sung
HS
Jung
Department of Oral and Maxillofacial Surgery, Tokyo Dental College , Chiba, Japan.
Takahiko
T
Shibahara
buccal mucosa; p75; proliferation; stem cells; wound healing