title: Tenascin-C induction in Whitlock-Witte culture: a relevant role of the thiol moiety in lymphoid-lineage differentiation.
abstract: The extracellular matrix (ECM) glycoprotein tenascin-C is expressed in a temporally and spatially restricted pattern during embryogenesis and carcinogenesis in association with stromal-epithelial interactions. First, we investigated the production of tenascin-C and other ECM glycoproteins in the established in vitro model system specific for the lymphoid-lineage hemopoiesis, i.e., the Whitlock-Witte (W-W) culture system. In murine primary long-term bone marrow cultures, tenascin-C was produced constitutively and was expressed significantly in higher amounts in this system than in the other established in vitro model system specific for the myeloid-lineage hemopoiesis, i.e., the Dexter culture system. 2-Mercaptoethanol (2-ME), a component of the W-W system, induced the secretion of tenascin-C and upregulated the expression of its mRNA. Furthermore, the reduced glutathione, which, like 2-ME, contains a thiol moiety, induced tenascin-C glycoprotein and its mRNA. By contrast, hydrocortisone (HC), a component of the Dexter system, inhibited the secretion of ECM glycoproteins. 2-ME and TGF-beta 1, the latter of which is known as an inducer of ECM glycoproteins, had an additive effect on the induction of tenascin-C when they were simultaneously added to the W-W system. The TGF-beta receptor binding analysis demonstrated that this induction by 2-ME was not mediated by the cell-surface TGF-beta receptors, suggesting that it was regulated independently of TGF-beta 1. Then, the role of thiol compounds in the lymphoid-lineage differentiation was examined. The omission of 2-ME from the W-W system completely eliminated its ability to support the lymphoid-lineage differentiation. Glutathione, which, unlike 2-ME, does not passively permeate through the plasma membrane, did not support the development of a lymphoid lineage. These results indicate that 2-ME, essential for the lymphoid-lineage differentiation in the W-W culture system, is a potent inducer of tenascin-C expression in vitro.
authors.affiliation: Division of Hemopoiesis, Jichi Medical School, Tochigi, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Sakai
authors.forename: M
authors.initials: M
authors.lastname: Ohta
authors.forename: H
authors.initials: H
authors.lastname: Kawakatsu
authors.forename: Y
authors.initials: Y
authors.lastname: Furukawa
authors.forename: M
authors.initials: M
authors.lastname: Saito
mesh_terms: D000818:Animals; D015816:Cell Adhesion Molecules, Neuronal / Q000096:biosynthesis* / Q000235:genetics; D002460:Cell Line; D005109:Extracellular Matrix / Q000378:metabolism; D016326:Extracellular Matrix Proteins / Q000096:biosynthesis* / Q000235:genetics / Q000378:metabolism; D006023:Glycoproteins / Q000378:metabolism; D006410:Hematopoiesis / Q000187:drug effects / Q000502:physiology*; D006854:Hydrocortisone / Q000494:pharmacology; D008221:Lymphoid Tissue / Q000187:drug effects / Q000378:metabolism / Q000502:physiology*; D008623:Mercaptoethanol / Q000494:pharmacology*; D051379:Mice; D008810:Mice, Inbred C57BL; D008811:Mice, Inbred DBA; D011485:Protein Binding; D012333:RNA, Messenger / Q000378:metabolism; D019063:Tenascin; D016212:Transforming Growth Factor beta / Q000378:metabolism
chemical_list: D015816:Cell Adhesion Molecules, Neuronal; D016326:Extracellular Matrix Proteins; D006023:Glycoproteins; D012333:RNA, Messenger; D019063:Tenascin; D016212:Transforming Growth Factor beta; D008623:Mercaptoethanol; D006854:Hydrocortisone