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Objective To observe the interferon-γ(IFN-γ),interhukin-2(IL-2)levels of Th1 cytokine and IL-4、IL-10 levels of Th2 cytokine in serum and culture supernatants of splenic cells of the rats in the prevention of experimentaI autoimmune uveoretinitis(EAU)by oral tolerance. Methods 72 Lewis rats were randomly divided into EAU group,oral tolerance group(which including 10 μg、100 μg、1 mg、10 mg of S antigen group respectively)and control group,12 rats in each group.The animal model of EAU was induced by immunization with S antigen(50 μg)and Freund's complete adjuvant.Oral tolerance 10 μg、100μg、1 mg and 10 mg group were fed with 1 ml mixture of 10 μg、100μg、l mg、10 mg S antigen and 1 mg trypsin inhibitor respectively by intuhation,once the other day,totally 7 times,and then induced EAU according to above methods;control group was fed with 1 ml mixture of phosphate buffered saline and 1 mg trypsin inhibitor,once the other day,totally 7 times,and then induced EAU.The clinical manifestation of EAU in the eye were recorded,the eyeballs were enucleated at the peak of EAU,followed by pathological grading.Meanwhile the serum was colleced;splentic cells were separated and cultured to collect the supernatant.Cytokine levels of IFN-γ,IL-2,IL-4 and IL-10 in serum.cultured supernatant of splenic cells were determined by enzyme-linked immunosorbent assay(ELISA). Results Compared with EAU and control group,the levels of IFN-γ and IL-2(Th1 eytokine)in the serum in 100 μg and 1 mg group were decreased while the levels of IL-4 and IL-10(Th2 eytokine)were inereased,the diffefences were statistically significant(F=51.9,68.8,35.7,7.5,P＜0.01).Compared the levels of Th1 and Th2 cytokines in the serum in 10 μg,10 mg group with EAU and control group.the differences were not statistically significant.In 100 gg、1 mg group,the levels of IFN-γ and IL-2(Th1 cytokine)in the culture supernatant of splenic cells were decreased while the Ievels of IL-4 and IL-10(Th2 cytokine)were increased,compared with EAU and control group,the differences were statistically significant(F=57.1,15.6,33.1,167.7,P＜0.01).Compared the levels of Th1 and Th2 eytokine in the culture supernatant of splenic cells in 10 μg、10 mg groups with EAU and control group,the difference are not statistically significant. Conclusions In the process to prevent EAU by oral intake,the levels of IFN-γ and IL-2 (Th1 cytokine)were decrease while the levels of IL-4 and IL-10(Th2 cytokine).Oral administration with tOO high or low dose of the antigen can not prevent EAU as well as the cytokine levels do not change obviously.Cytokines has played an important role in the prevention of EAU.
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Objective To observe the efficacy of the anti-tumor necrosis factor-α monoclonal antibody(TNF-α MCAb)in the treatment of experimental autoimmune uveoretinitis(EAU). Methods EAU animal models were induced by interphotoreceptor retinoid-binding protein(IRBP)R16 peptide with immunization.The rats were divided into 2 groups according to the injection times.TNF-α MCAh was administered intravenously on day 6 or 4,6 and 8 post-immunization respectively,and then to observe the clinical expression by slit-lamp microscope.Meanwhile,take the rats which did not accept TNF-α MCAb as conttol group.Delayed type hypersensitivity(DTH)responses were measured on day 13 postimmunization of IRBP R16;the rats were killed on day 14 post-immunization of IRBP R16,and then enucleated the eyes for histopathological examination.To detect the cytokine level of IFN-γ,IL-4 in serum and IFN-γ in aqueous humor by enzyme-liked immunosorbent assay(ELISA)on day 14 postinjection.The hyperplasia responses of antigen specific lymphocyte of draining lymph node cells were detected. Results The TNF-αMCAb group had mitigated ocular inflammation and decreased pathological grades compared with the control group;the IFN-γ concentrations in aqueous humor and serum were decreased,IL-4 was increased in serum;DTH responses were decreased;the hyperplasia responses of draining lymphocytes to IRBP R16 peptide were decreased,all the differences were statistically significant(P＜0.01).The rats accepted TNF-α MCAb thrice had much better curative effect than the rats injected once(P＜0.05). Conclusions Injection of TNF-α MCAb can inhibit ocular inflammation and specific immune cells of EAU remarkably and change the Th1/Th2 balance.Many times injections of TNF-α MCAb were more effective than once.
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Objective To investigate the expression and significance of inducible co-stimulator (ICOS) in experimental autoimmune uveoretinitis (EAU). Methods EAU was induced in 24 Lewis rats (immune group) by immunization with retinal S-antigen (50 ?g) and complete Freund′s adjuvant, and another 4 rats were in the control group. Anterior segment of the rats′ eyes were observed by split microscope every day. Immunohistochemical staining was performed using polyclonal antibodies to ICOS on the sections of the spleen which were obtained from the rats in immune group at the 7th, 12th, 15th and 21st days after immunisation respectively. Western blotting was performed to investigate the dynamic expression of ICOS protein in the spleen. The same procedures were made at the corresponding time points in the rats in control group. Results A few ICOS positive cells were observed in the normal spleen. The number of ICOS positive cells in immune group increased obviously at the 7th and 12th days after immunization, reached the peak at the 15th day, and decreased at the 21st day which was still higher than that in the control group. The result of Western blotting showed that the dynamic changes of ICOS protein was identical with the changes of positive-cell number detected by immunohistochemistry. Conclusions The enhanced expression of ICOS happens before EAU occurs, which increases when the inflammation occurs and deteriorates, and decreases at the alleviative stage of EAU. It suggests that ICOS participates in the formation, development and disappearance of EAU and plays an important role in the incidence of EAU.