The MRNA Expression Of TLR4, TLR9 In Experimental Allergic Neuritis Induced By P0 180-199 And Its Changes Under TWP

Objective Experimental allergic neuritis_EAN.is a T cell mediatedanimal model of Guillain-Barre' syndrome, characterized byinflammation and demyelination of the peripheral nervous system(PNS).EAN is a prototype disease for studies of mechanisms involved in CD4~+Tcell mediated autoimmunity and represents a useful animal model for thestudy of Guillain-Barre" syndrome in the human, the key pathogenesis isthe imbalance between Th1 type immune response and Th2 type immuneresponse. TLR is a receptor of innate immune system. It can recognizethe antigen by pathogen associated molecular patterns (PAMP), andactivate the antigen presenting cell(APC), producing co-stimulatingmolecule to activate T cells. Tripterygium wilfordii Polyeoside(TWP) isextracted from Chinese herbal medicine, which can strongly repressimmune response. In this study, we observed the expression of mRNA ofTLR4 and TLR9 in EAN rats and the changes for response to TWP. Tostudy the involvement of TLRs in EAN will give us new treatment ideafor GBS. or other autoimmune disease.Methods Male Lewis rats was immunized with the component ofPNS myelin sheath protein P0 180-199 (100microgram) and Freund'scomplete adjuvant, and TWP(40mg/kg.d) were profused intopost-immunization rats' stomach daily till the day they were put to death. Observe the clinical signs of rats and pathological changes in the sciaticnerves of rats. The rats in the group of immunized and control weresacrificed at 7days, 16days, 24days, 33days after being immunized.Embed sciatic to make paraffin section and stain it by HE stain and Luxolblue stain to observe the histopathology. TLR9 and TLR4 was detectedby RT-PCR dynamically which come from spleens, sciatic nerves,peripheral blood and lymphonodes.Results EAN group got the peak of clinical score at the 17d p.i,and the clinical manifestation ameliorated obviously at 33d .p.i themRNA expression of TLR4 got the peak at the 16d .p.i, then reducedgradually, but at the 33d. p. i, it was still higher that the CFA controlgroup(P＜0.05), there was significance difference among the four timepoint,P＜0.05.The mRNA expression of TLR9 was upregulated during thewhole process of the experiment, and was higher compared with thecontrol group.there was significance difference between the two neighborpoint,P＜0.05. The clinical manifestation of EAN+TWP group wasameliorated slightly compared with EAN group.The mRNA expression ofTLR4 and TLR9 was lower than EAN group at the 16d,24d ,33d p.i(p＜0.05).CFA group and NS group didn't show any clinical manifestation,and compared with NS group, the mRNA expression of TLR4 and TLR9was higher at any tissue, it got the peak at the 7d,and then reducedgradually. The mRNA expression of TLR4 and TLR9 in each tissue correlates with each other.Conclusions TLR4 and TLR9 may play a role in the pathogenesisof EAN by taking part in its inducing stage and effecting stage. TWP mayameliorate the EAN through inhabiting the TLR4 and TLR9 activation.CFA may exert its adjuvant effect via TLR4 and TLR9.