title: Effects of growth factors on cytokine production in serum-free cultures of human thymic epithelial cells.
abstract: Human thymic epithelial cells (TEC) of medullary phenotype were cultured for 14 days in a growth factor-defined serum-free medium. The effects of added growth factors on cell numbers and the production of cytokines were investigated by separate exclusion of the various growth factors from the medium. We found that hydrocortisone stimulated cell proliferation but inhibited the differentiation of TEC and significantly reduced the production of interleukin-1 alpha, interleukin-6 and granulocyte-macrophage colony stimulating factor. Insulin was found to enhance the differentiation of TEC and the production of the three cytokines. Transferrin and choleratoxin were found to inhibit cell proliferation, but they did not affect production of the cytokines. Exclusion of epidermal growth factor, however, leads to cell death. We conclude that it is essential to exclude hydrocortisone from the medium to optimize production of cytokines, and that transferrin and choleratoxin seem to be unnecessary constituents in serum-free cultures of human TEC.
authors.affiliation: Institute of Medical Anatomy, University of Copenhagen, Panum Institute, Denmark.
authors.forename: A
authors.initials: A
authors.lastname: Andersen
authors.forename: H
authors.initials: H
authors.lastname: Pedersen
authors.forename: K
authors.initials: K
authors.lastname: Bendtzen
authors.forename: C
authors.initials: C
authors.lastname: Röpke
mesh_terms: D002455:Cell Division / Q000502:physiology; D002478:Cells, Cultured; D002772:Cholera Toxin / Q000494:pharmacology; D016895:Culture Media, Serum-Free; D016207:Cytokines / Q000096:biosynthesis*; D004815:Epidermal Growth Factor / Q000502:physiology; D004847:Epithelial Cells; D004848:Epithelium / Q000276:immunology; D006133:Growth Substances / Q000502:physiology*; D006801:Humans; D006854:Hydrocortisone / Q000502:physiology; D007328:Insulin / Q000502:physiology; D013950:Thymus Gland / Q000166:cytology / Q000276:immunology*; D014168:Transferrin / Q000502:physiology
chemical_list: D016895:Culture Media, Serum-Free; D016207:Cytokines; D006133:Growth Substances; D007328:Insulin; D014168:Transferrin; D004815:Epidermal Growth Factor; D002772:Cholera Toxin; D006854:Hydrocortisone