title: T cell clones from psoriasis skin lesions can promote keratinocyte proliferation in vitro via secreted products.
abstract: Psoriasis vulgaris has been recognized lately as an immunologically mediated inflammatory skin disease. To analyze the pathogenetic role of T lymphocytes in the generation of psoriatic skin lesions, 105 T cell clones (TCC) and 10 T cell lines (TCL) were differentially isolated from dermis and epidermis of psoriatic skin specimens. Supernatants prepared from these T cells were studied for their effects on keratinocyte proliferation in vitro. Conditioned media from 14 of 77 epidermal TCC, 7 of which were CD8+, and from 8 of 28 dermal TCC, 5 of which were CD8+, reproducibly enhanced keratinocyte proliferation, with more pronounced mitogenic activities found in dermal TCC. Another 9 epidermal and 3 dermal TCC did not affect keratinocyte growth and supernatants from the remaining clones, as well as from the 5 epidermal and 5 dermal TCL, inhibited keratinocyte replication to varying degrees. Both mitogenic and suppressive activities were largely abolished by addition of an antiserum to interferon-gamma (IFN-gamma), while addition of epidermal growth factor or irradiated psoriatic TCL had little effect on the activities of the supernatants. These studies reveal that a subpopulation of lesional psoriatic T lymphocytes is capable of enhancing keratinocyte proliferation in vitro via secreted products. Their mitogenic capacity most likely requires IFN-gamma, but the ultimate effect is apparently determined by the presence of additional cytokines. Activation of T cells secreting such combinations of factors in vivo may contribute to the keratinocyte alterations characteristic of psoriatic skin lesions.
authors.affiliation: Department of Dermatology, Ludwig-Maximilians-University, Munich, FRG.
authors.forename: J C
authors.initials: JC
authors.lastname: Prinz
authors.forename: B
authors.initials: B
authors.lastname: Gross
authors.forename: S
authors.initials: S
authors.lastname: Vollmer
authors.forename: P
authors.initials: P
authors.lastname: Trommler
authors.forename: I
authors.initials: I
authors.lastname: Strobel
authors.forename: M
authors.initials: M
authors.lastname: Meurer
authors.forename: G
authors.initials: G
authors.lastname: Plewig
mesh_terms: D002455:Cell Division; D000078404:Epidermal Cells; D004815:Epidermal Growth Factor / Q000502:physiology; D006801:Humans; D066298:In Vitro Techniques; D007371:Interferon-gamma / Q000502:physiology; D015603:Keratinocytes / Q000166:cytology*; D008222:Lymphokines / Q000502:physiology; D008934:Mitogens; D011565:Psoriasis / Q000276:immunology* / Q000473:pathology; D012867:Skin / Q000166:cytology; D013601:T-Lymphocytes / Q000276:immunology*
chemical_list: D008222:Lymphokines; D008934:Mitogens; D004815:Epidermal Growth Factor; D007371:Interferon-gamma