内毒素耐受对共培养的中性粒细胞和单核细胞分泌TNF-α和IL-8的影响

Influence of endotoxin tolerance on TNF-α and IL-8 production in co-cultures of neutrophils and THP-1 cells

目的观察脂多糖(lipopolysaccharides,LPS)诱导的耐受对共培养的中性粒细胞和人单核细胞株THP-1细胞表达抗炎因子肿瘤坏死因子-α(tumor necrosis factor-α,TNF-α)和趋化因子白介素-8(Inter leukin-8,IL-8)水平的影响。方法采用1μg/m L牙龈卟啉单胞菌(Porphyromonas gingivalis,P.gingivalis)LPS或1μg/m L大肠杆菌(Escherichia coli,E.coli)LPS分别刺激共培养的中性粒细胞和THP-1细胞24 h,洗脱后,再次刺激24 h,诱导细胞产生耐受。采用ELISA技术检测细胞条件培养液中TNF-α和IL-8表达水平的变化。结果 P.gingivalis LPS或E.coli LPS单次刺激后,共培养的中性粒细胞和THP-1细胞分泌TNF-α和IL-8的水平均较刺激前明显增高(P<0.05);P.gingivalis LPS和E.coli LPS重复刺激后,共培养的中性粒细胞和THP-1细胞分泌的TNF-α水平较单次刺激后明显降低(P<0.05),但IL-8水平较单次刺激后明显增高(P<0.05)。结论共培养的中性粒细胞和单核细胞产生的内毒素耐受可能抑制TNF-α表达,促进IL-8表达,进而可能影响牙周组织的炎症和免疫反应。

Objective To observe the effects of endotoxin tolerance triggered by repeated stimulation of lipopolysaccharide （LPS） on TNF-α and IL-8 expressions in co-cuhures of neutrophils and THP-1 cells. Methods Co-cuhures of neutrophils and THP-lcells were pretreated with 1 μg/mL Porphyromonas gingivalis（P.gingivalis） LPS or 1 μg/mL Escherichia coli（E.coli） LPS for 24 h, washed and stimulated by the same LPS again for another 24 h. The levels of TNF-α and IL-8 in supernatants were deteeted by ELISA. Results The expression levels of TNF-α and IL-8 significantly increased in co-euhured cells stimulated by P.gingivalis LPS or E.coli LPS com- pared with those without any stimulation （P〈0.05）. The expression levels of TNF-α in cells restimulated by P.gingivalis LPS or E.coli LPS were obviously down-regulated compared with those stimulated by the same LPS only once （P〈0.05）, while the expression levels of IL-8 were significantly up-regulated in comparison with those secreted by co-cultures of neutrophils and THP-1 cells stimulated by the same LPS only once （P〈0.05）. Conclusion Endotoxin tolerance may suppress the secretion of TNF-α and promote the production of IL-8 in co-cultures of neutrophils and THP-1 cells.