Pseudomonas aeruginosa Inhibition of Flagellin-activated NF-kappaB and interleukin-8 by human airway epithelial cells.
Pseudomonas aeruginosa Inhibition of Flagellin-activated NF-kappaB and interleukin-8 by human airway epithelial cells.
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铜绿假单胞菌通过人气道上皮细胞抑制鞭毛蛋白激活的 NF-kappaB 和白细胞介素 8。
DOI：
10.1128/iai.01355-08
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发表时间：
2009
影响因子：
3.1
通讯作者：
Machen,TerryE
中科院分区：
文献类型：
--
作者：
Pena,Jose;Fu,Zhu;Schwarzer,Christian;Machen,TerryE
铜绿假单胞菌诱导的NF-κB活化和气道上皮细胞分泌促炎细胞因子需要细菌表达鞭毛蛋白。我们测试了P。气道上皮细胞和人气道上皮细胞分泌调节这种反应的因子。实验用Calu-3细胞系和原代培养的气管上皮细胞进行，铜绿假单胞菌PAK ΔfliC（鞭毛蛋白敲除）不激活NF-κB或白细胞介素-8（IL-8），但抑制鞭毛蛋白激活的NF-κB 40 - 50%和IL-8分泌20 - 25%。PAK Δ fliC还抑制IL-1β和Toll样受体2激动剂Pam 3CSK 4诱导的NF-κB。在菌株PAK、PAO 1和PA 14中观察到类似的抑制作用。从PAK Δ fliC或Calu-3 + PAK ΔfliC分离的条件培养基中存在抑制因子，但从单独的Calu-3细胞或经热处理的PAK Δ fliC分离的条件培养基中不存在抑制因子。PAK Δ fliC条件培养基的抑制作用从上皮的顶侧或基底侧发挥，在简单林格氏溶液中比在组织培养基中增强，并且不是由改变pH或消耗葡萄糖引起的。条件培养基的抑制作用通过煮沸消除，并且从过滤研究中似乎是由分子量<3 kDa的因子的作用引起的。这些研究以及对同基因突变体的进一步研究表明，气道上皮细胞对P. aerodysaccharide是鞭毛蛋白的促炎作用和小的（<3-kDa）热敏感因子的促炎作用的平衡的结果，所述热敏感因子不是脂多糖、C12高丝氨酸内酯、藻酸盐、CIF或外毒素A、S、T、U或Y。
Pseudomonas aeruginosa-induced activation of NF-κB and secretion of proinflammatory cytokines by airway epithelial cells require that the bacteria express flagellin. We tested whetherP. aeruginosaand human airway epithelial cells secrete factors that modulated this response. Experiments were performed with both the Calu-3 cell line and primary cultures of tracheal epithelial cells.P. aeruginosastrain PAK ΔfliC(flagellin knockout) did not activate NF-κB or interleukin-8 (IL-8) but inhibited flagellin-activated NF-κB by 40 to 50% and IL-8 secretion by 20 to 25%. PAK ΔfliCalso inhibited NF-κB induced by IL-1β and Toll-like receptor 2 agonist Pam3CSK4. Similar inhibitions were observed with strains PAK, PAO1, and PA14. The inhibitory factor was present in conditioned medium isolated from PAK ΔfliCor Calu-3 plus PAK ΔfliC, but it was not present in conditioned medium isolated from Calu-3 cells alone or from PAK ΔfliCthat had been heat treated. Inhibition by PAK ΔfliC-conditioned medium was exerted from either the apical or the basolateral side of the epithelium, was enhanced in simple Ringer's solution over that in tissue culture medium, and did not result from altered pH or depletion of glucose. The inhibitory effect of conditioned medium was abolished by boiling and appeared from filtration studies to result from effects of a factor with a molecular mass of <3 kDa. These and further studies with isogenic mutants led to the conclusion that the NF-κB and IL-8 response of airway epithelial cells toP. aeruginosaresults from a balance of proinflammatory effects of flagellin and antiinflammatory effects of a small (<3-kDa), heat-sensitive factor(s) that is not lipopolysaccharide, C12 homoserine lactone, alginate, CIF, or exotoxin A, S, T, U, or Y.