Regulatory effects of gamma-interferon on IL-6 and IL-8 secretion by cultured human keratinocytes and dermal fibroblasts.
Gamma-interferon (IFN-gamma) is produced by T cells and plays an important role in immunological and inflammatory processes. To determine the effects of IFN-gamma on interleukin (IL)-6 and IL-8 secretion, normal human keratinocytes (NHKs), human squamous cell carcinoma cell line (HSC-1) cells, and human dermal fibroblasts (HDFs) were incubated with 100 U/ml of recombinant (r) IFN-gamma in the presence of various stimulants. HSC-1 cells and HDFs spontaneously secreted both IL-6 and IL-8 into the culture medium. NHKs secreted detectable levels of IL-8, but not of IL-6, and IL-8 secretion increased over 20 fold by stimulation with 10 nM of phorbol 12-myristate 13-acetate (PMA). rIFN-gamma inhibited IL-8 secretion in both HSC-1 cells and PMA-stimulated NHKs. On the other hand, it enhanced IL-1 alpha- and TNF alpha-induced IL-8 secretion in NHKs. In HDFs, rIFN-gamma inhibited IL-8 secretion, but enhanced secretion of IL-6, regardless of whether they were stimulated with IL-1 alpha or PMA. These results suggest that IFN-gamma has different regulatory effects on IL-6 and IL-8 secretion in NHKs and HDFs, depending on the stimulus.
Maruyama
K
K
Department of Dermatology, Fukushima Medical College, Japan.
Zhang
J Z
JZ
Nihei
Y
Y
Ono
I
I
Kaneko
F
F
D002294:Carcinoma, Squamous Cell; D046508:Culture Techniques; D004797:Enzyme-Linked Immunosorbent Assay; D005347:Fibroblasts / Q000187:drug effects* / Q000378:metabolism; D006801:Humans; D007371:Interferon-gamma / Q000008:administration & dosage*; D015850:Interleukin-6 / Q000032:analysis / Q000378:metabolism*; D016209:Interleukin-8 / Q000032:analysis / Q000378:metabolism*; D015603:Keratinocytes / Q000187:drug effects* / Q000378:metabolism; D012878:Skin Neoplasms; D014407:Tumor Cells, Cultured / Q000187:drug effects
D015850:Interleukin-6; D016209:Interleukin-8; D007371:Interferon-gamma