An experimental study on cell interaction between fibroblasts of periodontal ligament and cells from Malassez epithelial rests co-cultured in vitro.

Abstract

: The purpose of this studywas to investigate the interaction between cells from Malassez epithelial rest (MER) and fibroblasts of periodontal ligament (PLF) co-cultured in vitro. MER formed typical pavement-like sheets, whilePLF were characterized by a long, slender shape and were arranged in a characteristic storiform pattern. PLF showed a marked increase in the number of cells on a daily basis, and cell proliferation followed an arithmetical progression. In contrast, MER exhibited a much lower proliferation rate. MER grew multilayers of PLF, but PLF did not grow well on multilayers of MER. When MER were co-cultured with PLF, although both cells showed almost the same population in the early time period, MER occupied a greate area in the later time period. These results suggest that MER begin to grow upon stimulation and may differentiate into keratinized stratified squamous epithelium on fibrous connective tissue.

Regulatory mechanisms of periodontal regeneration

“…Moreover, the possibility that some materials secreted by the Malassez epithelial rest suppress the proliferation of fibroblasts can be envisaged. The process may correlate closely with the homeostasis function and prevention of ankylosis (Inoue et al, 1995b).…”

The effects of epithelial rests of Malassez cells on periodontal ligament fibroblasts: A co-culture investigation for epithelialmesenchymal interactions

“…Inoue et al reported interactions between ERM cells and PDL fibroblasts using co-cultures in vitro, but they cultured ERM cells and PDL fibroblasts that were mixed in the bottom of each culture dish (14). In contrast, our study used a co-culture system in which a membrane with 0.4 μm pores allowed the exchange of medium, including factors secreted by ERM cells, but cell-to-cell interactions between ERM cells and PDL fibroblasts were inhibited (16).…”

“…Periodontal tissues were obtained from the premolars of swine, according to the method of Inoue et al (14). PDL fibroblasts were then incubated in a humidified atmosphere of 95% air and 5% CO2 at 37℃ for primary culture, using alpha-minimal essential medium (Gibco, Invitrogen Corporation, Carlsbad, CA, USA) containing 10% fetal bovine serum (Sigma, St Louis, MO, USA) supplemented with 2 ml gentamycin (10 mg/ml, Sigma).…”