title: T-cell development in human thymoma.
abstract: Human thymoma is derived from thymic epithelial cells and often associated with a large number of cortical thymocytes. Since thymic epithelial cells play key roles in T-cell development in the normal thymus, we hypothesized that the neoplastic epithelial cells of thymoma may support T-cell differentiation. We attempted to reconstitute the T-cell development in vitro by using neoplastic epithelial cells isolated from thymoma. CD34, a stem cell marker, was expressed on a proportion of CD4-CD8- cells in thymoma. These CD34+CD4-CD8- cells also expressed both IL-7R alpha-chain and common gamma-chain. Purified CD4-CD8- cells from thymomas were cultured with the neoplastic epithelial cells, and their differentiation into CD4+CD8+ cells via CD4 single positive intermediates was observed within 9 days' co-culture in the presence of recombinant IL-7. The CD34+CD4-CD8- cells purified from a normal thymus also differentiated to CD4+CD8+ cells in an allogeneic co-culture with the neoplastic epithelial cells of thymoma. In addition, a pleural dissemination from thymoma contained a large amount of cortical thymocytes. These results suggest that the neoplastic epithelial cells retain the function of thymic epithelium and can support T-cell development in thymomas.
authors.affiliation: First Department of Surgery, Osaka University Medical School, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Inoue
authors.forename: Y
authors.initials: Y
authors.lastname: Fujii
authors.forename: M
authors.initials: M
authors.lastname: Okumura
authors.forename: S
authors.initials: S
authors.lastname: Miyoshi
authors.forename: H
authors.initials: H
authors.lastname: Shiono
authors.forename: K
authors.initials: K
authors.lastname: Fukuhara
authors.forename: Y
authors.initials: Y
authors.lastname: Kadota
authors.forename: H
authors.initials: H
authors.lastname: Matsuda
mesh_terms: D000328:Adult; D015703:Antigens, CD / Q000096:biosynthesis / Q000276:immunology; D015496:CD4-Positive T-Lymphocytes / Q000166:cytology / Q000187:drug effects / Q000276:immunology; D018414:CD8-Positive T-Lymphocytes / Q000166:cytology / Q000187:drug effects / Q000276:immunology; D002454:Cell Differentiation / Q000276:immunology; D002478:Cells, Cultured; D018920:Coculture Techniques; D004847:Epithelial Cells / Q000166:cytology; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D018189:Immunomagnetic Separation; D015851:Interleukin-7 / Q000494:pharmacology; D016131:Lymphocyte Subsets / Q000166:cytology / Q000276:immunology / Q000378:metabolism; D008875:Middle Aged; D011994:Recombinant Proteins / Q000494:pharmacology; D017154:Stromal Cells / Q000166:cytology / Q000276:immunology; D013601:T-Lymphocytes / Q000276:immunology / Q000473:pathology*; D013945:Thymoma / Q000276:immunology / Q000473:pathology*; D013953:Thymus Neoplasms / Q000276:immunology / Q000473:pathology*
chemical_list: D015703:Antigens, CD; D015851:Interleukin-7; D011994:Recombinant Proteins