Experiment Study On Effects Of STAT6Decoy Oligonucleotides On Interleukin-13Expression Of Spleen Lymphocytes Of Bronchial Asthma Mice

objective: Bronchial asthma is a kind of chronicinflammatory of the airways,which is involved in many kinds of cells andcellular elements, such as eosinophils,T lymphocytes,neutrophil，granulocytes, mastocytes, alveolar epithelial cells. Its key feature isrecurring symptoms, reversible airflow obstruction and remodeling of theairways. The sustained activation and over-expression of signaltransduction and activator of transcription6(STAT6) promote thepredominantly expression of T helper type2(Th2) cells. Th2cellssecrete mediators of inflammation such as interleukin (IL)-4，IL-5,IL-13and so on,which is the main pathophysiological foundation. This studywas to investigate the effects of STAT6decoy Oligonucleotides oninterleukin-13expression of spleen lymphocytes of bronchial asthmamice through together culturing STAT6decoy ODN and spleenlymphocytes of asthmatic mice. Methods:48female BALB/c micewere randomly divided into two groups and spleen lymphocytes ofasthmatic mice were divided into5groups: normal controlgroup(groupⅠ);asthma group(groupⅡ).an control group (group A),anasthma OVA group(group B), an asthma liposome group(group C),anasthma STAT6decoy ODN group(group D), an asthma STAT6 scrambled ODN group(group E).Asthma model was duplicated withovalbumin(OVA) and aluminum hydroxide. Mice were immunized ondays0and7and14by intraperitoneal injection per day with. From day21to28Mice were aerosolized with5%OVA aqueous for30min perdays. Equal NS was used for intraperitoneal injection, sensitization andinhalation instead of antigen solution in normal control group.Sensitizated the last time24hours later, mice were killed to get thesample of bronchoalveolar lavage fluid(BALF) and the pulmonary.Spleen lymphocytes of mice were separated by EZ-SepTM mouse andcultured in vitro,then synthetized STAT6decoyOligonucleotides(ST-ODN) modified by sulfide and scrambled STAT6Oligonucleotides(SC-ODN) were introduced into lymphocytes of micewith cationic liposome transfection，then OVA stimulated lymphocytes toactivate. The number of white blood cells, eosinophils and lymphocytesin branehoalveolar lavage fluid was measured by microscope;Pathological changes of lung were observed by HE staining; Thencollection for RNA extraction and reverse transcription, real-time PCRwas carried out after optimization of PCR parameter.The concentration ofIL-13in the supernatants of culturing spleen lymphocytes was measuredby enzyme-linked immunosorbent assay(ELISA). Results:1.The tissuesection was observed and found that the inflammation of the asthmaticgroup was significantly increased compared with the normal control group;2. Compared with the normal control group,the number of whiteblood cells, lymphocytes, eosinophils in the branehoalveolar lavage fluidof the asthma group were significantly increased(P<0.01);3. Comparedwith group A and D, the expression of IL-13mRNA in the spleenlymphocytes was significantly increased in group B and group C andgroup E(P<0.01), while there were no significant differences betweengroup A and group D,between group B and group C and groupE(P>0.05)；4. Compared with group A and D, protein express of IL-13increased markedly in the supernatants of lymphocytes culturing in groupB and C and E (P<0.01), while there were no significant differencesbetween the group A and group D,between group B and group D andgroup E(P>0.05). Conclusion: STAT6decoy ODN can be transcriptedinto the lymphocytes successfly. The transcription of IL-13mRNA andsecretion of IL-13could be inhibited specificlly by STAT6decoy ODN.