TNF-α,IFN-γ对角质形成细胞杀灭金黄色葡萄球菌作用的影响

目的观察不同浓度肿瘤坏死因子(TNF)-α、干扰素(IFN)-γ及二者联合作用下对金黄色葡萄球菌在角质形成细胞中生存状态的影响,了解角质形成细胞的抗菌功能及相关因素。方法以金黄色葡萄球菌侵入角质形成细胞为实验模型,对照组加入等量灭菌PBS,以平板菌落计数法观察不同浓度(20ng/mL,40mg/mL)下TNF-α、IFN-γ及二者同一浓度联合作用下胞内活菌数量。结果与对照组相比,在20ng/mL浓度下,各组胞内活菌数量变化不明显(P>0.05)。在40ng/mL浓度下,与对照组比较,IFN-γ组活菌数量减少,差异有统计学意义(P<0.05);TNF-α+IFN-γ组活菌数量有所减少,但不及单用IFN-γ效果明显(P>0.05),TNF-α组活菌数量无明显变化(P>0.05)。结论 IFN-γ可以增强角质形成细胞杀菌功能,TNF-α与IFN-γ联合作用下,细胞杀灭胞内细菌功能弱于单用IFN-γ,而单用TNF-α对角质形成细胞杀灭金黄色葡萄球菌作用无明显影响。

Effects of TNF-alpha, IFN-gamma on the ability of keratinocytes to kill intracellular stalphylococcus aureus

Objective To study the bactericidal activity of keratinocytes to Staphylococcus aureus in the presence of TNF-α,IFN-γ and their combination.Methods The keratinocytes were co-cultured with Staphylococcus aureus to establish the Staphylococcus invasion model of skill cell,then the different concentrations of TNF-α,IFN-γ and their combination were added into the culture,24 h later the number of intracellular viable bacteria was counted,while the same amount of sterilized PBS was used as control.Results Compared with the control group,each the number of intracellular viable bacteria did not change significantly under the condition of 20 ng/mL of either TNF-α or IFN-γ(P> 0.05),as well as 40 ng/mL of TNF-α(P>0.05).However,it was reduced significantly after the addition of 40 ng/mL of IFN-γ(P<0.05);while was also decreased by the combination of TNF-α and IFN-γ,of which effect was less than that achieved by IFN-γ alone(P> 0.05).Conclusion IFN-γ,not TNF-α,can enhance the bactericidal function of keratinocytes,and the bactericidal effect is weaker when the treatment is combing IFN-γ with TNF-α.