ABSTRACT
Background Studies show that regulatory T cells (Treg) are a kind of T cell subsets to negatively regulate immune response,and play an important role in maintaining immune homeostasis and immune tolerance.Autoimmune uveitis is an autoimmune disease,the regulation of Treg cells in pathogenesis and progression of autoimmune uveitis is not fully unelucidated.Objective This study was to observe the dynamic changes of Treg in experimental autoimmune uveitis (EAU) rats and explore the role of Treg cells in the pathological process of EAUrats.Methods Eighty four 6-8 week-old SPF Lewis rats were randomly divided into model group and control group.The mixed emulsifier of interphotoreceptor retinoid-binding protein (IRBP)1177-1191,tuberculin (TB),complete Freund adjuvant (CFA) and PBS (300 μl) was subcutaneously injected in double rear foot pad,abdominal side and back,and only equal amount of TB,CFA and PBS emulsifier was used in the same way in the control group.Ocular inflammation symptoms was examined at 9,13,18,23,28,35 and 48 days after modeling and scored based on the severity of the inflammatory.Six rats of each group were sacrificed in above time points respectively for the histopathological examination of iris,ciliary body and retinas by haematoxylin-eosin staining.The lymphocytes were isolated and cultured from rat spleens,and the proportion of Foxp3-labelled cells,a specific marker of Treg cells,was assayed by flow cytometry.The relative expression level of Foxp3 mRNA in the lymphocytes detected by using realtime quantitative PCR (RT-PCR).The use and care of the rats complied with the ARVO Statement.Results Eye inflammatory response appeared at 8 days after immunization,showing vasodilation and hyperemia of rat iris in the model group,and the response peaked at 13 days,with exudation and hypopyon in the anterior chamber.The highest inflammatory scores were 3.75±0.42 at day 13,and the ocular inflammation reaction was gradually relieved after that and disappeared at 23 days after immunity.A significant difference in ocular inflammatory scores of model rats was found among different time points (F =81.709,P ＜ 0.001);while no inflammatory symptom was observed in the control group.Histopathology examination showed obvious infiltration of inflammatory cells in the iris,ciliary body and retinas in model rats,including neutrophils,lymphocytes and mononuclear cells.The proportion of Foxp3-labelled cells in spleen lymphocytes was (5.50 ± 0.64)％,(13.36 ± 0.98)％,(10.34 ± 0.79)％,(9.58 ± 1.02)％,(6.73 ±0.81)％ and (5.58 ± 0.47) ％ in the model group on day 13,18,23,28,35,48 respectively,with statistically significant differences in comparison with (2.80 ± 0.38) ％,(3.36 ± 0.53) ％,(3.65 ± 0.57) ％,(3.37 ± 0.43) ％,(3.33±0.50)％ and (3.13±0.61)％ in the control group (t=-6.272,-15.556,-11.910,-9.753,-6.154,-5.491,all at P＜0.01).The change trend of Foxp3 mRNA expression was consistent to the dynamic change of the proportion of Foxp3-labelled cells.Conclusions The pathogenesis and development is closely associated with the dynamic changes of CD4+ CD25 + Foxp3+ Treg cells in EAU rats.
ABSTRACT
Background Our previous studies found that mesenchymal stem cells (MSCs) can ameliorate experimental autoimmune uveitis (EAU) and reduce tissue impairment.Its mechanism is still pending.Objective This study was performed to investigate the effects of MSCs on T cell subsets and antigen presenting cells (APCs) in EAU rats.Methods MSCs were isolated from bone marrow of six male Wistar rats and cultured by plastic adherence method.Twelve female Lewis rats were assigned randomly into MSCs group and PBS group.EAU rat model was induced by immunization with 200 μl emulsion containing 30 μg interphotoreceptor retinoid-binding protein (IRBP) 1177-1191 polypeptide fragment R16 and complete Freund adjuvant (CFA).The eye manifestations of the rats were observed and scored under the slit lamp microscope after modeling.The R16-immunized rats were treated intravenously with 5×106/ml MSCs for 3 consecutive days from day 9 to 11 after modeling in the MSCs group,and the equivalent volume of PBS was used with the same way in the PBS group.Fifteen days after modeling,the spleens and draining lymph nodes were collected to evaluate the proportion of interferon-γ (IFN-γ) positive CD4+ T cells,interleukin-17 (IL-17)positive CD4+ T cells and forkhead helix transcription factor p3 (Foxp3) positive CD4+ T cells by flow cytometry.The T cells and APCs from the different groups were cocultured and divided into PBS cocultured group,MSCs cocultured group, PBS-MSCs cross-cultured group and MSCs-PBS cross-cultured group under the stimulation of R16 at the concentration of 0.3,1.0 or 10.0 μg/ml, and the proliferation indexes of the T cells in different groups were assayed by 5-bromodeoxyuridine (BrdU) Elisa kit.The use of experimental animals complied with the regulations on the management of experimental animals promulgated by the national science and technology commission.Results The ocular surface inflammatory scores of 11,12,13 and 14 days after modeling in the MSCs group were significantly lower than that in the PBS group (t=3.825,5.100,4.250,3.400, all at P＜0.05).Compared with the PBS group, the proportions of IFN-γ positive CD4+ T cells in spleen and draining lymph notes were considerably decreased in the MSCs group (t =5.651,4.376, both at P＜0.05) , so were the IL-17+ CD4+ T cells (t =3.300,4.925, both at P＜0.05).However,the proportions of Foxp3 + CD4+ T cells in spleen and draining lymph notes were statistically raised in the MSCs group compared with the PBS group (t =-5.172,-2.825,both at P＜0.05).The proliferation index of T cells increased with the rise of R16 dose in the PBS cocultured group, and the proliferation indexes were all declined in the MSCs cocultured group compared with the PBS cocultured group under the stimulation of 0.3,1.0 and 10.0 μg/ml of R16 (P =0.027,0.000,0.000).In addition, significant reduces of proliferation indexes of T cells were seen in the PBS-MSCs cross-cultured group and MSCs-PBS cross-cultured group in comparison with the PBS cocultured group when stimulated by 1.0 μg/ml and 10.0 μg/ml R16 (1.0 μg/ml R16 : P =0.001,0.000;10.0 μg/ml R16:P=0.000,0.000).Conclusions MSCs can ameliorate EAU by inhibiting the functions of antigen-specific T cells and APCs and up-regulating T regulatory cells in EAU rats.
ABSTRACT
Objective To investigate the action mechanism of blood-stage treatment that affects psoriasis vulgaris using observation of the Th17/Treg expression.Methods A total of 32 patients ( blood heat group,n =17 ; blood stasis group,n =15) and 15 healthy people ( control group,n =15 ) were observed.The frequencies of Th17 and Treg in peripheral blood were detected by flow cytometric analysis in patients before and after treated by heat-clearing and blood-cooling decoction,qi-enriching and blood-activating decoction.Results The ratio of Th17/Treg in peripheral blood [ blood heat group (4.21 ± 0.52 )％ ;blood stasis group( 3.32 ± 0.43 )％ ] was significantly increased in patients compared with controls [ ( 1.79 ±0.18)％ ] ( P ＜0.01 ).After herbal treatment,the ratio of Th17/Treg expression in the blood heat group [ ( 2.41 ± 0.22 ) ％ ] and in blood stasis group [ ( 2.02 ± 0.12 ) ％ ] was significantly decreased ( P ＜ 0.05 ),respectively.Conclusions Blood-stage treatment works well on Th17/Treg expression in patients with psoriasis vulgaris.
ABSTRACT
Objective To observe the proportion changes of CD4+CD25+FOXP3+ T cells in peripheral blood of patients with Vogt-Koyanagi-Harada disease(VKH)before and after one month of treatment. Methods The peripheral blood samples from 15 patients with VKH disease before and after one month of treatment by glucocorticoid,and from 15 healthy volunteers were collected,and lymphoeytes were separated from them.CD4+CD25+regulatory T cells were Iabeled by antibodies of cell surface marker CD4、CD25 and transcription factor FOXP3.The proportion of CD4+CD25+FOXP3+ T cells were detected by flow cytometry. Results Before the treatment,the percentage of CD4+ CD25+FOXP3+ T cells in periphery blood was(0.30±0.19)%of CD4+ cell in VKH patients,and(1.41±0.52)%in control group,the difference was statistically significant(t=7.665,P＜0.01);after one month of treatment,the VKH patients group was(1.28±0.54)%which close to the control group.However there were two patients whose CD4+ CD25+ T cells inereased extraordinarily after one month of treatment. Conclusions The proportion of CD4+ CD25+ FOCP3+ T cells in periphery blood in VKH patients were lower than control group obviously before treatment,but were close to eontrol group after treatment.Those results indicated that VKH diseases may be associated with the decreased proportion of CD4+ CD25+ regulatory T cells.