Bacsi Attila, Choudhury Barun K, Dharajiya Nilesh, Sur Sanjiv, Boldogh Istvan
Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX77555, USA.
J Allergy Clin Immunol. 2006 Oct;118(4):844-50. doi: 10.1016/j.jaci.2006.07.006. Epub 2006 Aug 28.
Pollen is known to induce allergic asthma in atopic individuals, although only a few inhaled pollen grains penetrate into the lower respiratory tract.
We sought to provide evidence that subpollen particles (SPPs) of respirable size, possessing both antigenic and redox properties, are released from weed pollen grains and to test their role in allergic airway inflammation.
The release of SPPs was analyzed by means of microscopic imaging and flow cytometry. The redox properties of SPPs and the SPP-mediated oxidative effect on epithelial cells were determined by using redox-sensitive probes and specific inhibitors. Western blotting and amino acid sequence analysis were used to examine the protein components of the SPP. The allergenic properties of the SPP were determined in a murine model of experimental asthma.
Ragweed pollen grains released 0.5 to 4.5 microm of SPPs on hydration. These contained Amb a 1, along with other allergenic proteins of ragweed pollen, and possessed nicotinamide adenine dinucleotide (reduced) or nicotinamide adenine dinucleotide phosphate (reduced) [NAD(P)H] oxidase activity. The SPPs significantly increased the levels of reactive oxygen species (ROS) in cultured cells and induced allergic airway inflammation in the experimental animals. Pretreatment of the SPPs with NAD(P)H oxidase inhibitors attenuated their capacity to increase ROS levels in the airway epithelial cells and subsequent airway inflammation.
The allergenic potency of SPPs released from ragweed pollen grains is mediated in tandem by ROS generated by intrinsic NAD(P)H oxidases and antigenic proteins.
Severe clinical symptoms associated with seasonal asthma might be explained by immune responses to inhaled SPPs carrying allergenic proteins and ROS-producing NAD(P)H oxidases.
已知花粉可诱发特应性个体发生过敏性哮喘，尽管只有少数吸入的花粉颗粒能进入下呼吸道。
我们试图提供证据，证明可吸入大小的亚花粉颗粒（SPPs）具有抗原性和氧化还原特性，是从杂草花粉颗粒中释放出来的，并测试它们在过敏性气道炎症中的作用。
通过显微镜成像和流式细胞术分析SPPs的释放情况。使用氧化还原敏感探针和特异性抑制剂测定SPPs的氧化还原特性以及SPP对上皮细胞的氧化作用。采用蛋白质印迹法和氨基酸序列分析来检测SPP的蛋白质成分。在实验性哮喘小鼠模型中测定SPP的致敏特性。
豚草花粉颗粒在水化时释放出0.5至4.5微米的SPPs。这些颗粒含有Amb a 1以及豚草花粉的其他致敏蛋白，并具有烟酰胺腺嘌呤二核苷酸（还原型）或烟酰胺腺嘌呤二核苷酸磷酸（还原型）[NAD(P)H]氧化酶活性。SPPs显著增加了培养细胞中的活性氧（ROS）水平，并在实验动物中诱发了过敏性气道炎症。用NAD(P)H氧化酶抑制剂预处理SPPs可减弱它们增加气道上皮细胞中ROS水平以及随后气道炎症的能力。
豚草花粉颗粒释放的SPPs的致敏效力由内在的NAD(P)H氧化酶产生的ROS和抗原性蛋白共同介导。
与季节性哮喘相关的严重临床症状可能是由对携带致敏蛋白和产生ROS的NAD(P)H氧化酶的吸入性SPPs的免疫反应所解释的。
