Effect Of STAT1Gene Silencing On The Expression Of INF-γ, IL-5and ICAM-1in The Mouse Model Of Asthma

Objective: objective: STAT1is a protein of connection between thevarious membrane receptors and effectors of signal transduction, whichplays an important role in the regulatory network of cytokines. RNAinterference is a new technology that is gene knockout study with recentdevelopment.We used RNA interference technology to silence the geneof transducer and transcription activation of the1, which affects theexpression of INF-gamma, IL-5and ICAM-1. STAT1is silenced byRNA interference which is expected to become an efficient mean toimprove the asthmatic airway inflammation and hyperresponsiveness tobring a new treatment for asthma genes and molecular level to asthmabronchial epithelial cells.Methods:32-week-old BALB/C mice were randomly divided into fourgroups; normal group, PBS group, random fragments group and siRNAgroup. PBS group, random fragments group and siRNA group weresensitized by freshly prepared OVA/Al（OH）₃suspension in the firstday and the fourteenth day.While the normal group was injected1mL ofsaline siRNA group used the concentrated siRNA40ul to Intranasalmethod in26to29days. PBS group used the PBS to Intranasal method . Random fragments group used the blank plasmid to Intranasal method.the normal group was used saline to Intranasal method.In the28to30days, the normal group was used saline to intranasally and the other threegroups used OVA to Intranasal method to arouse. The mice were killed in12hours after the last intransally.The cell of bronchoalveolar lavage fluidwas counted.At the same time, supernatant of bronchoalveolar lavagefluid was detected the expression of IFN-gamma,IL-5and ICAM-1.Lungtissue was stained by immunohistochemical and HE.We use SPSS17.0analyse the results.Results:1. HE staining of lung tissue of normal mice can be seen: thebronchial smooth wall, the alveolar septa meager alveolar space and noinflammatory exudate. HE staining of empty plasmid group and PBSgroup asthmatic mice lung biopsy can be observed: a large number ofinflammatory cell infiltration around the bronchial mucosal edema, whichis main of EOS, and bronchial mucosal edema. Inflammatory infiltrationof SiRNA group significantly reduced to comparewith empty plasmidgroup and PBS group.2. STAT1protein express the airway epithelialcells of mice.3. STAT1protein expression level of siRNA group wassignificantly lower than the PBS group and the random fragments group,but higher than the normal group.4. White blood cell, eosinophils andlymphocytes were counted in bronchoalveolar lavage fluid.Their cell was reduced in the normal group compared with PBS and the fragmentsgroup.Conclusion:1.Asthma murine model was successfully constructed.2.siRNA can be transfected into airway epithelial cells in asthmatic miceby intranasal way.3.siRNA silencing STAT1gene can inhibit theexpression of the asthmatic airway epithelial cells STAT1protein..4.siRNA silence STAT1gene can regulate the expression of INF-γ,IL-5and ICAM-1.5. SiRNA silencing of STAT1can reduce the asthma airwayinflammation in mice.