Functional analysis of eosinophil infiltration mechanisms in chronic sinusitis in relation to transcription factor activation

近几十年来，副鼻窦感染的整体病理观点发生了深刻的变化和演变。通过释放各种细胞因子和趋化因子，局部嗜酸性粒细胞的聚集与鼻窦疾病的程度密切相关。在本研究中，我们探讨了慢性鼻窦炎中嗜酸性粒细胞浸润的机制与转录因子激活的关系。1)我们检测了细胞因子在鼻窦粘膜中的表达和CD4阳性细胞亚群的分布。低嗜酸性粒细胞仅表现为干扰素-γ基因表达增加。相反，其他患者表现出相似的细胞因子谱，高表达GM-CSF、IL-5和嗜酸性粒细胞趋化蛋白基因CCR4+的CD4+细胞在高嗜酸性粒细胞增多，导致CXCR3+/CCR4+细胞比率降低。这些发现支持了慢性鼻窦炎是Th2介导的疾病过程的概念。2)我们研究了…核因子-kappaB(NF-κB)的活化更多地发生在鼻窦粘膜，其活化程度与局部细胞因子基因的表达有关。P50亚基的胞浆和胞核定位主要位于上皮细胞。IL-8、IL-16和嗜酸性粒细胞趋化蛋白基因表达水平与上皮细胞中NF-κB活化程度呈显著正相关。通过启动相关细胞因子的转录途径，这种激活可能与嗜酸性粒细胞的募集有关。3)我们检测了培养的鼻窦上皮细胞中NF-κB的激活及其伴随的细胞因子的表达。经肿瘤坏死因子-α处理后，核因子-κB的活化程度增加2.3倍。免疫细胞化学也显示刺激后细胞胞核染色增强，胞浆染色增加。此外，丙酸氟替卡松和白三烯拮抗剂都有效地抑制了培养细胞的激活。这些结果阐明了维持鼻窦粘膜结构性NF-κB活性的分子机制，并将提供嗜酸性粒细胞募集与慢性炎症持续时间之间的直接因果联系

The overall pathological view of paranasal sinus infection has profoundly changed and evolved in recent decades. A close correlation has been noted between local eosinophil recruitment and the extent of sinus disease through the release of various cytokines and chemokines. In the present study, we have investigated mechanisms of eosinophil infiltration in chronic sinusitis in relation to transcription factor activation1) We examined cytokine expression and the distribution of CD4-positive cell subsets in the sinus mucosa. The patients with low eosinophilia only showed an increase in IFN-γ mRNA expression. In contrast, the other patients showed similar cytokine profiles with high expression levels for GM-CSF, IL-5, eotaxin mRNA CCR4-positive CD4+ cells were also significantly higher in patients with high eosinophilia, leading to decreased CXCR3+/ CCR4+ cell ratio. These findings provide support for the concept of chronic sinusitis as a Th2-mediated disease process2) We examined whether … More the activation of nuclear factor-kappa B (NF-κB) occurred in the sinus mucosa and related the degree of activation to local cytokine gene expression. Both cytoplasmic and nuclear localization of the p50 subunit was observed mainly in the epithelial layer. Significant correlations were observed between the degree of epithelial NF-κB activation and the levels of IL-8, IL-16, and eotaxin mRNA. The activation appears responsible for the recruitment of eosinophils through the initiation of the transcriptional pathway of the related cytokines3) We examined NF-κB activation and concomitant cytokine expression triggered by TNF-α stimulus in cultured sinus epithelial cells. Treatment with TNF-α augmented the degree of NF-κB activation by 2.3 folds. Immunocytochemistry also showed intense nuclear staining with increased staining in the cytoplasm occurred after stimulation. Further, both fluticasone propionate and leukotriene antagonists effectively inhibited the activation in the cultured cells. These results elucidate the molecular mechanisms responsible for the maintenance of constitutive NF-κB activity in sinus mucosa and would provide a direct causal link between the recruitment of eosinophils and persistence of chronic inflammation Less