Interactions between cloned gingival or periodontal ligament cells and oral epithelial cells in vitro.

Interactions between epithelial cells and fibroblast clones were examined to determine whether various fibroblasts clones derived from gingival or periodontal tissues responded differently to oral epithelial cells. We provide evidence that epithelial root sheath (ERS) cells enhanced collagen type I (CI) expression in most periodontal clones, whereas ERS cells variably influenced CI expression of gingival fibroblast clones. Modulation of collagen type III (CIII) expression in both gingival and periodontal clones by ERS cells was less in magnitude and mostly suppressive in gingival clones. Fibronectin (Fn) expression in many gingival and periodontal clones was decreased in cells associated with ERS cells. On the other hand, the influence of gingival epithelial cells on fibroblast clones tended to be inhibitory, especially in periodontal clones. Thus, gingival epithelial (GE) cells suppressed the expression of collagen types I and III and Fn in most periodontal clones. Except for suppression of Fn expression, GE cells had less influence on CI and CIII expression in gingival clones. The modulations of fibroblast extracellular matrix components by ERS and GE have profound implications for the regulation of the development, repair and regeneration of the periodontal tissues.