The Effects Of Yupingfeng Polysaccharides On Tissue Structure And Immune Functon In Mice Peyer’s Patches

Yupingfeng Powder is a classic prescription contained in the Chinese Pharmacopoeia and the Chinese Veterinary Pharmacopoeia.Its effective part group is Yupingfeng polysaccharides(YPF-P)that has been proveded have many biological activities,such as antiviral effect and enhanced immunity.Our previous studies found that YPF-P can effectively enhance the intestinal mucosal immune function in mice,However,the immune regulation mechanism has not been elucidated.In this study,Peyer’s Patches(PPs),an important role of intestinal mucosal immune system,were used to study the effects of YPF-P on intestinal mucosal immune system by research the changes in PPs tissue structure and immune function.mechanism.This study is divided into two parts: in vivo animal experiment and in vitro cell experiment.The animal experiment compares the changes of PPs in normal mice,different doses of YPF-P immunosuppsressed mice and YPF-P positive control mice,to investigate the anti-injury and protective effect of YPF-P on mice PPs;in vitro cell assay based on cell culture technology,observe changes in cell proliferation and activation,changes in cytokine levels and changes in lymphocyte subsets,in order to study YPF-P effect of on proliferation,activation and immune function of mice PPs.The results of this thesis can further elucidate the immunoregulatory mechanism of YPF-P on mice intestinal mucosa,and provide theoretical guidance and experimental support for the development and application of YPF-P,and have important theoretical and application value.This study is carried out in the following aspects:Firstly,96 SPF mice were randomly divided into 6 groups: blank control group(0.2 m Lsaline),YPF-P positive control group(YPF-P200mg/Kg),cyclophosphamide(Cy)immunosuppsression.The group(Cy 80 mg/Kg)and the low,medium and high dose YPF-P group(100,200,400 mg/Kg YPF-P)were fed for 1 week,and the small intestine PPs were taken.The morphological changes of PPs were detected by immunohistochemistry.The expression of TLR4 in PPs was identified by immunohistochemistry.The functional effects of YPF-P on PPs in the small intestine of mice were investigated.Secondly,to investigate the proliferative effect of YPF-Pon PPs lymphocytes,in vitro isolation of mice PPs and preparation of PPs lymphocyte suspension,dosing,cell culture technique,MTT assay for detection of PPs lymphocytes and Con A synergistically with different doses of YPF-P(0.5,1,2,4,8 mg/m L),proliferation tested after different time(0,8,12,16,24,36 h)were used to investigate the proliferative effect of YPF-P on PPs lymphocytes.Then,ELISA kit was used to detect the changes of cytokines IL-2,IL-4 and IFN-γ in PPs lymphocyte suspension,and the changes of NO levels,and to explore the regulation effect of YPF-P on PPs lymphocyte-associated cytokines.Finally,flow cytometry was used to detect the changes of CD3+CD4+,CD19+ and CD8+ cells in PPs lymphocytes,and the lymphocyte subpopulation analysis was carried out to further investigate the regulation mechanism of YPF-P on PPs lymphocytes.The results indicated that YPF-P can improve the body weight of immunosuppressed mice,increase the volume and quantity of PPs in small intestine of mice,relieve and repair the immune damage of PPs in small intestine caused by Cy,and effectively promote the proliferation of PPs lymphoid tissue,different doses of YPF-P can enhance the activity of PPs lymphocytes,and promote the proliferation and activation of PPs lymphocytes.At the same time,YPF-P could promote the production and secretion of IL-2,IL-4,IFN-γ and NO in mice PPs,could change the ratio of T and B lymphocytes in mice PPs lymphocytes and significantly increase the ratio of CD4+/CD8+.In conclusion,this study demonstrates that YPF-P could enhance intestinal mucosal immune function by regulating PPs in the small intestine of mice.