Expression of Fibronectin and Integrins in Cultured Periodontal Ligament Epithelial Cells

Abstract

The process of attachment of epithelial cells obtained from the porcine periodontal ligament (cell rests of Malassez) to different extracellular matrix proteins and their expression of fibronectin and integrin receptors were studied by means of immunocytochemistry, in situ hybridization, and time-lapse cinemicrography techniques. The cell lines of periodontal ligament epithelial cells (PLE cells) attached to and spread rapidly on fibronectin, vitronectin, and type I collagen. One of the cell lines also attached to laminin, while the other cell line showed poor attachment to both laminin and Matrigel, a basement membrane material. By use of the in situ hybridization technique, some PLE cells were found to express the fibronectin gene strongly. Immunocytochemical staining localized fibronectin in extracellular fibrils and intracellular granules. Fibronectin was also found in the tracks left behind by the cells migrating on the substratum. Arg-gly-asp-ser peptide inhibited the attachment of the PLE cells to fibronectin, laminin, type I collagen, and vitronectin by 47%, 43%, 83%, and 94%, respectively, suggesting that the cell-matrix interactions were partly mediated by receptors related to the integrin family. Antibodies against the beta 1-integrin subunit stained the cell bodies and the plasma membrane projections of spreading cells. After 24 h or longer in culture, beta 1-integrins were localized to the regions of cell-cell contact. Cinemicrography of the arg-gly-asp-ser-peptide-treated cells demonstrated that the spreading and migration of isolated cells were prevented by the peptide. The peptide did not appear to dissociate the cell-cell contacts or interfere with migration of spread-cell colonies.(ABSTRACT TRUNCATED AT 250 WORDS)

Regulatory mechanisms of periodontal regeneration

“…The blastic-cells in the periodontal ligament may be supplied from cells related to blood vessels. A subsequent suggestion is that homeostasis of the periodontal ligament space may be regulated by Malassez rests (Abiko et al, 1994;Inoue et al, 1992Inoue et al, , 1995aUitto et al, 1992;Wesselink and Beertsen, 1993).…”

“…The latter growth factor participates in regulating the proliferation of periodontal ligament cells and in the decline in their alkaline phosphatase activity, which suggests that fibroblast growth factors may suppress the differentiation of periodontal ligament cells. The possibility that the Malassez epithelial rest is also involved in regulating the proliferation and differentiation of periodontal ligament cells remains (Abiko et al, 1994;Inoue et al, 1993bInoue et al, , 1995aShimono et al, 1998;Uitto et al, 1992;Wesselink and Beertsen, 1993).…”

Effects of a Nano-structured Surface Layer on Titanium Implants for Osteoblast Proliferation Activity

“…With the help of a profileometer the three most characteristic pieces of data were Sa = 0.836 µm, Scx = 8.38 µm and Sdr = 1.3 µm [35]. In the literature there are reports of quite wide intervals (between grooves) on the machined surface with Ra, in the range 0.08 -4.7 µm [53].…”

Effect of dental cyst epithelium-conditioned medium on collagenase production by periodontal ligament fibroblasts.

“…In the light of these findings, we assumed that the antral lining epithelium of dental cysts, which are considered to originate from the epithelial cell rests of Malassez, has the capacity to stimulate PLF collagenase production, as observed with gingival epithelial cells [8]. Although Brunette and coworkers [16,17] succeeded in culturing porcine cell rests of Malassez, there are, to our knowledge, no reports on the culture of these cells from humans without fibroblast contamination. Therefore, we attempted mechanical separation of the lining epithelium from cyst wall granulation and connective tissues using the method of Oda et al [18,19], and obtained the epithelium-conditioned medium using tissue culture procedures.…”