Antiviral Activities Of Lung-Qi Deficiency Mice With IRPS Against H3N2 Swine Influenza Virus

Lung-qi deficiency causes lung gas loss,weakness and lacking of synthesis gas,grooming divergence, which showing the immunocompromised state. Isatais root polysaccharide(IRPS) is the traditional Chinese medicine(TCM) for pulmonary disease, it has antipyretic, detoxication effect.The active ingredient of IRPS has anti-viral and immunomo- dulatory effect.The Swine Influenza Virus(SIV) is an important pathogen, it causes an infectious disease of swine respiratory tract, and SIV sub-type H3N2 is widely spreads in the farm, it could attack swine immune system and lead to immunosu- ppression, eradicates with difficulty in the formalization pig farm.At present, SI does not have any medicine.The TCM has a unique advantage of easy to get, and not only low-toxicity, but also cheap.The experiment evaluate the fuction of IRPS directly against H3N2 SIV on the screening model of MDCK cells,and observe that IRPS indirectly anti-H3N2 swine flu virus on TCM symptom animal model.Enriched the TCM pharmacy anti-SIV,screened the new drugs anti-virus based on TCM symptom animal model and providing more theoretical basis of TCM symptom animal model and preventing and controlling animal epidemic disease by the cocktail therapy of integrated Chinese and Western medicines. Research contents and results shown as below:First,preparing IRPS by ethanol extractraction, the effect of IRPS against A/Swine/Henan/2010(H3N2) SIV in vitro through using MTT assay on the screening model of MDCK cells were evaluated. The results showed that the IRPS has certain toxic effect to the MDCK cell, TC50 and TC0 are 7.273mg/ml, 2.504mg/ml, respectively. IRPS interrupt SIV, the concentrations of suppression and elimination are 10.158,19.291,0.038,respectively. It is very effective that the inhibitory and interrupting effects of IRPS on the SIV infected MDCK cell. But in margin for safety concentrations, the effect of viral elimination is not to be obvious.Second, in order to explain pathogenic changes of Lung-qi deficiency Balb/c mice infect with H3N2 SIV, 6-8 weeks Lung-qi deficiency Balb/c mice were infected with SIV by intranasal route, and we observed and analyzed indexes such as body weight, organ index, and immunological index. The results showed that mice infected with SIV lung deficiency observed poor physical index, losing body weight, pulmonary edema, pulmonary hemorrhage, and alveolar macrophages were proliferated, severe bronchial epithelial shedding, perivascular inflammatory cell infiltration and other pathological changes. NO levels and Ig G levels, and proinflammatory and anti-inflammatory cytokines were decreased. It influence anti-inflammatory effects and it suppressed anti-viral effects, such as IFN-γ and TNF-α levels. In addition, compared with healthy mice, lung-qi deficiency mice infected with SIV increased its pathological changes and systemic damage through a comprehensive analysis of the body weight, pathological changes in the lung and physical changes of body.Third, we observed and analyzed changes of physical index, body weight, organ index, and pathologic changes of lung. And we also observed immunological indexes, such as the activities of peritoneal macrophages, the splenic lymphocyte proliferation, the serum levels of NO and Ig G at the post-infection 2nd,5th and 9th days of SIV A/Swine/Henan/2010(H3N2) infection of Lung-qi deficiency Balb/c mice model treated with IRPS. The results showed that IRPS could significantly improved symptom condition and body weight gain, and improved pulmonary edema, pulmonary hemorrhage, inflammatory cell infiltration, alveolar-interstitial proliferation and improved lesion of the SIV-infected mice. IRPS could regulate the immune responses and enhanced the systemic ability to repair inflammatory by promoting pro-inflammatory cytokines such as IL-1β, IL-6 and TNF-α levels, besides enhancing the antiviral effect by promoting the secretion of IL-12 and IFN-γ and extenuate the pulmonic inflammatory response to reduced the expression of IL-10. In addition, different doses of IRPS against SIV increased the systemic biological activity, in comprehensive evaluation, IRPS concentration of 75mg/kg is effective.In summary, SIV A/Swine/Henan/2010(H3N2) could cause pathologic changes in Lung-qi Deficiency Balb/c mice, and symptoms of Lung-qi deficiency mice were advanced by SIV; IRPS influenced on the cytokine levels and the physical indexes of SIV-infected mice, and also it has anti-viral effects.