title: Induction of insulin-like growth factor 2 expression in a mesenchymal cell line co-cultured with an ameloblast cell line.
abstract: Various growth factors have been implicated in the regulation of cell proliferation and differentiation during tooth development. It has been unclear if insulin-like growth factors (IGFs) participate in the epithelium-mesenchyme interactions of tooth development. We previously produced three-dimensional sandwich co-culture systems (SW) containing a collagen membrane that induce the differentiation of epithelial cells. In the present study, we used the SW system to analyze the expression of IGFs and IGFRs. We demonstrate that IGF2 expression in mesenchymal cells was increased by SW. IGF1R transduces a signal; however, IGF2R does not transduce a signal. Recombinant IGF2 induces IGF1R and IGF2R expression in epithelial cells. IGF1R expression is increased by SW; however, IGF2R expression did not increase by SW. Thus, IGF2 signaling works effectively in SW. These results suggest that IGF signaling acts through the collagen membrane on the interaction between the epithelium and mesenchyme. In SW, other cytokines may be suppressed to induce IGF2R induction. Our results suggest that IGF2 may play a role in tooth differentiation.
authors.affiliation: Cell-Materials Interaction Group, Biomaterials Unit, National Institute for Materials Science, 1-1 Namiki, Tsukuba, Ibaraki, 305-0044, Japan.
authors.forename: Asako
authors.initials: A
authors.lastname: Matsumoto
authors.forename: Hidemitsu
authors.initials: H
authors.lastname: Harada
authors.forename: Masahiro
authors.initials: M
authors.lastname: Saito
authors.forename: Akiyoshi
authors.initials: A
authors.lastname: Taniguchi
mesh_terms: D000565:Ameloblasts / Q000166:cytology* / Q000378:metabolism*; D000818:Animals; D002417:Cattle; D002460:Cell Line; D018920:Coculture Techniques; D005786:Gene Expression Regulation; D007335:Insulin-Like Growth Factor II / Q000235:genetics / Q000378:metabolism*; D008648:Mesoderm / Q000166:cytology* / Q000378:metabolism*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D051381:Rats; D017526:Receptor, IGF Type 1 / Q000235:genetics / Q000378:metabolism; D017527:Receptor, IGF Type 2 / Q000235:genetics / Q000378:metabolism
chemical_list: D012333:RNA, Messenger; D017527:Receptor, IGF Type 2; D007335:Insulin-Like Growth Factor II; D017526:Receptor, IGF Type 1