Effects of tumor necrosis factor (TNF)-α,interleukin(IL)-6 and interferon(IFN)-γ on the expression of CD68 in HaCaT cells / 中华皮肤科杂志

ABSTRACT

Objecfive To study the effects of some cytokines such as TNF-α,IL-6 and IFN-γ as well as lipopolysaccharide on CD68 expression in HaCaT cells.Methods Human HaCaT keratinocytes were randomly divided into natural proliferation group (without stimulation),IFN-γ-stimulated group,TNF-α-stimulated group,LPS-stimulated group and IL-6 stimulated group.The work concentration of TNF-α,IL-6,IFN-γ and LPS was 50 mg/L.HaCaT cells were collected after 24-hour treatment with the cytokines followed by the examination of CD68 expression with flow cytometry,immunohistochemistry and reverse transcription(RT)-PCR,respectively.Results Compared with untreated HaCaT cells,the count of CD68-positive cells was elevated in cells stimulated by TNF-α(t=3.60,P<0.01),IL-6(t=3.93,P<0.01),IFN-γ(t=2.38,P<0.05)and LPS(t=2.52,P<0.05),and the effect of TNF-α and IL-6 was stronger than that of IFN-γ and LPS.Among the four cytokines,only IL-6 enhanced the mean fluorescence intensity of CD68-positive cells (t=8.34,P<0.01).After 24-hour treatment with TNF-α,IFN-γ and IL-6,CD68 expression was observed in the cytoplasm and on the membrane of HaCaT cells and was stronger in cells treated with TNF-α and IL-6 than in those with the other cytokines.A significant increase was observed in the CD68 mRNA expression after 24-hour treatment with TNF-α (t=4.34,P<0.01),IL-6 (t=7.52,P<0.01)and IFN-γ (t=2.81,P<0.05);TNF-α and IL-6showed a stronger promotive effect than IFN-γ.Conclusion IL-6,TNF-α,IFN-γ and LPS can upregulate the CD68 expression in HaCaT cells.