Morphological and functional characteristics of human gingival junctional epithelium

Qian Jiang,Hong Ruan,Xuehua Guo,Yin Luo,Youcheng Yu

doi:10.1186/1472-6831-14-30

Abstract

BackgroundThis study aims to observe the morphological characteristics and identify the function characteristics of junctional epithelium (JE) tissues and cultured JE cells.MethodsParaffin sections of human molar or premolar on the gingival buccolingual side were prepared from 6 subjects. HE staining and image analysis were performed to measure and compare the morphological difference among JE, oral gingival epithelium (OGE) and sulcular epithelium (SE). Immunohistochemistry was applied to detect the expression pattern of cytokeratin 5/6, 7, 8/18, 10/13, 16, 17, 19, and 20 in JE, OGE and SE. On the other hand, primary human JE and OGE cells were cultured in vitro. Cell identify was confirmed by histology and immunohistochemistry. In a co-culture model, TEM was used to observe the attachment formation between JE cells and tooth surface.ResultsHuman JE was a unique tissue which was different from SE and OGE in morphology. Similarly, morphology of JE cells was also particular compared with OGE cells cultured in vitro. In addition, JE cells had a longer incubation period than OGE cells. Different expression of several CKs illustrated JE was in a characteristic of low differentiation and high regeneration. After being co-cultured for 14 d, multiple cell layers, basement membrane-like and hemidesmosome-like structures were appeared at the junction of JE cell membrane and tooth surface.ConclusionsJE is a specially stratified epithelium with low differentiation and high regeneration ability in gingival tissue both in vivo and in vitro. In co-culture model, human JE cells can form basement membrane-like and hemidesmosome-like structures in about 2 weeks.

Highlights

This study aims to observe the morphological characteristics and identify the function characteristics of junctional epithelium (JE) tissues and cultured JE cells
After stained with HE, no keratinization or epithelial ridges existed in JE tissue which was divided into basal layer and suprabasal layer, while keratinized or partially keratinized epithelium, dense and irregular epithelial ridges projecting into adjacent connective tissue were found in dark-stained sulcular epithelium (SE) and oral gingival epithelium (OGE) tissues (Figure 3A)
JE cells were different from SE and OGE in morphology and had clear boundary with SE (Figure 3B)

Summary

Introduction

This study aims to observe the morphological characteristics and identify the function characteristics of junctional epithelium (JE) tissues and cultured JE cells. As a special structure at dento-gingival junction, JE is different from other epitheliums (OGE, SE) in origin, cell morphology, proliferation and differentiation [2,3]. Scholars have studied the JE using in vitro cell culture models and molecular cytological techniques using animal and/or human OGE cells, periodontal ligament epithelial cells and oral epithelial cells [13,14,15,16]. Though these cells are oral epithelial cells, they cannot model primary JE cells completely due to differences in source, morphology, structure, differentiation and stimuli that induce proliferation

Objectives

Methods

Results

Discussion

Conclusion