Objective: The objective of this study was to investigate how gingival fibroblasts cultured on microstructured model surfaces affect epithelial morphogenesis and other cell functions in a cocultured epithelium while conducting a molecular analysis of interactions between biomaterials employing periodontal tissue cells.
Materials and methods: We are the first to have successfully co-cultured gingival fibroblasts together with gingival keratinocytes on biofunctionalized, microstructured model surfaces and, in the resulting co-cultured epithelium, examined the molecules of tissue homeostasis, the differentiation marker keratin (K) 1/10, and involucrin after 1- and 2-week periods of cultivation. Desmoplakin was perceived as evidence of cell-to-cell contact and thus as proof of epithelial integrity. We also analyzed the basement membrane component laminin-5. The aforementioned co-culture model without gingival fibroblasts was used as a control set-up.
Results: On the protein level, indirect immunofluorescence demonstrated the presence of K1/10, involucrin and the basement membrane component laminin-5 in the co-cultured epithelium in both culture periods. Furthermore, we observed that these epithelial markers had become re-oriented toward the suprabasal cell layers which, in turn, reflects the native in-vivo gingival epithelium. We identified cell-to-cell adhesion as a function of desmoplakin after just 1 week. In the mRNA analysis using quantitative RT-PCR after 2 weeks of cultivation, we noted a considerable rise in relative gene expression that was time-dependent for the early keratinocyte differentiation marker K1 and late marker involucrin.
Conclusions: Our findings demonstrate that gingival fibroblasts on microstructured model surfaces are vitally important for tissue- specific cell functions such as epithelial morphogenesis and other biological cell functions such as differentiation and epithelial integrity. These study findings can thus contribute to the optimization and/or new development of biomaterials currently used in dental medicine.