Regulatory Effects Of N-butanol Fraction Of Illigera Rhodantha Hance. On The Immune Balance Of Th17/Treg In CIA Mice

Objective:To investigate the regulatory effect and mechanism of nbu IR on the immune balance of Th17/Treg in CIA mice.Methods: CIA animal model was established by DBA/1 mice in vivo.CIA mice were randomly divided into the model control group（CIA）,methotrexate group（MTX）,low-dose nbu IR group（nbu IR-L）,medium-dose nbu IR group（nbu IR-M）and high-dose nbu IR group（nbu IR-H）,and Blank group（Blank）.Each group is implemented gastric administration respectively.After the intervention,serum levels of IL-1β,IL-6,TNF-α,and PGE2 were detected by ELISA.The levels of Th17 and Treg cells were detected by flow cytometry.The m RNA levels of IL-17 A,Foxp3,RORγt,IL-23 R,JAK2 and STAT3 in spleen lymphocytes of CIA mice were detected by fluorescence quantitative PCR.In the vitro experiment,mice spleen lymphocytes were isolated,and cytokine induction and drug intervention were added.Dividing the cells into Blank group（Blank）,model group（Model）,methotrexate（MTX）,low-dose nbu IR group（nbu IR-L）,medium-dose nbu IR group（nbu IR-M）and high-dose nbu IR group（nbu IR-H）.The levels of Th17 cells were detected by flow cytometry after culturing 60 hours.The m RNA levels of IL-17 A,RORγt,IL-23 R,JAK2 and STAT3 in mice spleen lymphocyteswere detected by fluorescence quantitative PCR.Results: 1.In vivo,serum levels of TNF-α and PGE2 are significantly reduced.But in the expression levels of serum IL-6 and IL-1β,nbu IR-L was lower than that of CIA group with statistical difference（P<0.05）.The ratio of Th17 cells in spleen lymphocytes in CIA mice was significantly increased（P<0.01）,while the ratio of Th17 cells in MTX,nbu IR-M and nbu IR-H groups was significantly lower than that in CIA group（P<0.01）.In contrast,Treg cells in CIA mice showed lower expression（P<0.01）compared with the blank control group.While the percentage of Treg cells in MTX,nbu IR-L,nbu IR-M,and nbu IR-H groups were significantly higher than those in CIA group（P<0.01）.The expression levels of IL-17 A,RORγt,IL-23 R,JAK2and STAT3 m RNA in spleen lymphocytes of CIA group increased significantly（P<0.01）,while the expression levels of Foxp3 m RNA were significantly decreased（P<0.01）.The expression levels of IL-17 A,RORγt,IL-23 R,JAK2and STAT3 m RNA were significantly inhibited by MTX and nub IR groups（P<0.01）.Except the m RNA expression levels of Foxp3 of nbu IR-L group showed no significant difference compared with CIA group,the other groups showed significant difference（P<0.01）.2.In vitro experiments,after differentiation,th17 cells ratio is significantly elevated（P<0.01）.Compared with the CIA control group,as the drug concentration increasing,the drug inhibition rate on Th17 cells increased,that is,the content of Th17 cells decreased.In the expression levels of IL-17 A,RORγt,IL-23 R,JAK2,and STAT3 m RNA,each group had different degrees of reduction compared with the model group.Conclusion: nbu IR may inhibit the differentiation and proliferation of Th17 cells by inhibiting the action of IL-23R/JAK2/STAT3 axis,thereby promoting Treg cells.We can regulate immune function by regulating the balance of Th17 and Treg cells.