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Sjögren's syndrome (SS) is a chronic inflammatory autoimmune disorder that affects mainly salivary and lacrimal glands, but its cause remains largely unknown. Clinical data indicating that SS occurs in a substantial proportion of patients with lupus points to common pathogenic mechanisms underlying the two diseases. To address this idea, we asked whether SS develops in the lupus-prone mouse strain sanroque (SAN). Owing to hyper-activation of follicular helper T (Tfh) cells, female SAN mice developed lupus-like symptoms at approximately 20 wk of age but there were no signs of SS at that time. However, symptoms typical of SS were evident at approximately 40 wk of age, as judged by reduced saliva flow rate, sialadenitis, and IgG deposits in the salivary glands. Increases in serum titers of SS-related autoantibodies and numbers of autoantibody-secreting cells in cervical lymph nodes (LNs) preceded the pathologic manifestations of SS and were accompanied by expansion of Tfh cells and their downstream effector cells. Thus, our results suggest that chronic dysregulation of Tfh cells in salivary gland-draining LNs is sufficient to drive the development of SS in lupus-prone mice.
Subject(s)
Animals , Female , Humans , Mice , Autoantibodies , Autoimmunity , Disease Models, Animal , Immunoglobulin G , Lacrimal Apparatus , Lupus Erythematosus, Systemic , Lymph Nodes , Saliva , Salivary Glands , SialadenitisABSTRACT
In order to investigate the effects of p-nitrophenylalanine on the differentiation of T lymphocyte,human epidermal growth factor receptor 2(HER2)mutants were constructed by incorporating p-nitrophenylalanine to the extracellular domain of HER2.Mice were immunized with HER2 mutant to analyze the effects of p-nitrophenylala-nine on the differentiation of T cell subsets.The results showed that the immunogenicity of HER2 protein was significantly enhanced by incorporation of immunogenic amino acids.HER2 mutants induced production of more anti-WT-HER2 antibody and greater titer of antibody than PBS and wild-type HER2 in the fifth week.The differ-entiation frequency of Th1 and Th2 cells showed no significant difference,but the differentiation frequency of Tfh cell was found to increase from 4％ to 8％,while the differentiation frequency of Treg cell was found to decrease from 5％ to 1％ through flowcytometry analysis.The gene expression of Bcl-6 and FOXP3 were determined by quantitative real-time PCR.The results showed that the expression of Bcl-6 mRNA increased about 2 fold,while the expression of FOXP3 mRNA could be decreased to about 50％ in HER2 mutant-immunized group.The secre-tion level of IL-21 in serum was also detected to increase from 4 to 28 pg/mL in HER2 mutant-immunized group.The above results confirm that HER2 mutants containing p-nitrophenylalanine can cause an efficient immune response by activating Tfh cell differentiation.
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Objective To analyze the changes in follicular helper T (Tfh) cells during HIV-1 in-fection, to investigate the influences of Tfh cells and Tfh-related molecules on HIV-1 progression and to pro-vide references for further research on using Tfh cells in highly active antiretroviral therapy ( HAART) and vaccines. Methods This study enrolled 33 patients with HIV-1 infection, including 11 long-term nonpro-gressors (LTNP), 10 rapid progressors (RP) and 12 typical progressors (TP), and 11 healthy subjects (normal controls, NC). Peripheral blood mononuclear cells were isolated from each subject. Multicolor flow cytometry was performed to detect CD4+CD45RA-CXCR5+Tfh and CD4+CD45RA-CXCR3-CXCR5+PD-1+Tfh subsets and the levels of inducible costimulatory molecule (ICOS), IFN-γ and IL-21. Moreover, the levels of IL-10 and the percentages of CD19+B cells in plasma samples of each group were also analyzed. Relationships among Tfh, CD4 and B cells were analyzed. Results The percentages of both Tfh subsets were higher in patients with HIV-1 infection than in NC. Compared with NC, LTNP had the highest percent-age of CD4+CD45RA-CXCR3-CXCR5+PD-1+Tfh cells (P<0. 05). Expression of Tfh-related molecules ICOS, IFN-γ and IL-21 were enhanced significantly upon Staphylococcus enterotoxin B ( SEB) stimulation, ICOS+Tfh cells were negatively related with HIV-1 progression, but had a positive correlation with CD19+B cells (r=-0. 49, P<0. 01; r=0. 60, P<0. 05). IL-10 level in plasma increased significantly in patients withHIV-1 infection , especially in TP and RP ( TP vs NC : P＜0. 01 ; RP vs NC : P<0. 05 ) . Conclusion HIV-1 patients and NC had significant differences in the expression of Tfh cells and Tfh-related molecules in peripheral blood. ICOS+Tfh cells were closely related to the progression of HIV-1 infection and the function of B cells.
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Systemic lupus erythematosus (SLE) is a severe systemic autoimmune disease, which is characterized by excessive production of autoantibodies caused by B cell hyperactivity. Thus,reducing au-toantibody production can control the development of SLE,and understanding the molecular and cellular fac-tors involved in the differentiation of B cells will provide new therapeutic targets. Follicular helper T cells (Tfh) are defined as a new subset of CD4+T cells specialized in providing help to B cells,which is suspec-ted to play a critical role in the pathogenesis of SLE. In the present review,we give an overview of key mole-cules involved in the differentiation,regulation and functions of Tfh,discuss the roles of Tfh in SLE and de-scribe some potential therapeutic targets for SLE.
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Objective To investigate whether follicular helper T(Tfh) cells were involved in the development of Henoch-Sch?nlein purpura(HSP) and Henoch-Sch?nlein purpura nephritis(HSPN) in chil-dren through affecting CD40/CD40L axis. Methods Fifty-five subjects were enrolled in this study and di-vided into four groups as follows:22 children with HSP but without renal involvement(Group A),11 chil-dren with HSPN presenting with microhematuria(Group B),11 children with HSPN presenting with micro-hematuria and proteinuria (Group C) and 11 healthy children (control group). Flow cytometry was per-formed to detect the percentages of CD19+B cells and their subsets,CD19+B cells and CD19+CD38+B cells secreting different Ig classes,CD19+CD40+B cells and their subsets and Tfh cells expressing CD40 ligand (CD40L). Results Compared with the control group,the percentages of CD19+CD86+B,CD19+CD138+B and CD40L+Tfh cells significantly increased in Group C(P<0.05) and slightly increased in Groups A and B (P>0.05). No significant difference in the percentages of CD19+B cells, CD19+CD27+B cells, CD19+B cells or CD19+CD38+B cells expressing IgG, IgM, IgD, CD19+B cells or CD19+B cell subsets secreting CD40 was found between the control group and Groups A,B and C(P>0.05). Moreover,the percentages of CD19+B and CD19+CD38+B cells secreting IgA and IgE in Groups A,B and C were higher than those in the control group(P<0.05). Secretion of IgA by CD19+B and CD19+CD38+B cells were positively correla-ted with the expression of CD40L by Tfh cells(P<0.05). Conclusion Tfh cell-mediated abnormal expres-sion of CD40/CD40L might play an important role in the development of HSP and be related to the clinical severity of renal involvement in HSPN.
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Objective To investigate the inhibitory effect and underlying mechanism of mesenchymal stem cell (MSC) derived from different sources on follicular helper T cell (Tfh cell). Methods Umbilical cord-derived MSC (UC MSC), bone marrow-derived MSC (BM MSC) and fat-derived MSC (Fat MSC) were co-cultured with peripheral blood mononuclear cell (PBMC) for 48 h. A control group was established. Flow cytometry was adopted to calculate the proportion of Tfh cells among the lymphocytes in four groups. The content of interleukin (IL)-21 in the supernatant was detected by enzyme-linked immune absorbent assay (ELISA) in four groups. BM MSC was co-cultured with PBMC, and supplemented with indoleamine 2,3-dioxygenase (IDO) inhibitor 1-methyl tryptophan (1-MT), IL-10 antibody, human leukocyte antigen (HLA)-G antibody in the 1-MT group, IL-10 inhibition group, HLA-G inhibition group and BM MSC group without addition of other substances. After 48 h culture, flow cytometry was used to detect the percentage of Tfh cells among lymphocytes. Results Flow cytometry demonstrated that compared with the control group, the proportion of Tfh cells in the BM MSC group was significantly decreased (P<0.05). Compared with the BM MSC group, the percentage of Tfh cells in the UC MSC and Fat MSC groups was significantly higher (both P<0.05). ELISA revealed that compared with the control group, the IL-21 content in the BM MSC group was significantly decreased (P<0.05). Compared with the BM MSC group, the IL-21 contents were considerably higher in the UC MSC and Fat MSC groups (both P<0.05). The analysis of underlying mechanism revealed that the proportions of Tfh cells in the 1-MT, IL-10 inhibition and the HLA-G inhibition groups were (1.75±0.07)%, (1.31±0.09)% and (1.50±0.03)%, respectively, which were significantly higher than (1.03±0.43)% in the BM MSC group (all P<0.05). Conclusions BM MSC exerts the highest inhibitory effect upon the differentiation of Tfh cell and IL-21. The mechanism underlying suppressing the differentiation of Tfh cells differentiation is probably correlated to promoting the secretion of IDO.
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In order to explore the regulation mechanisms of follicular helper T cell (Tfh Cell) differentiation,optimized conditions of in vitro induction from both peripheral blood mononuclear cells and MAC sorted Na(i)ve CD4 + T cells to human Tfh cells were developed.Induction efficiency difference of TCR signal anti-hCD3e stimulation between coated on solid phase and in soluble phase was also determined.Differentiation efficiency of CD4 + CXCR5 + ICOS+PD-1 + Tfh cell was determined by FACS while the expression level of IL-21 in cell supernatant was determined by ELISA tests.An ultimate induction condition that 5 μg/mL coated overnight anti-hCD3e stimulated na(i)ve CD4 + T cells to differentiate into Tfh at an up to 20.4％ percentage was finally determined.The optimization of in vitro induction protocol of human Tfh provided an effective examine platform for the studies on Tfh differentiation mechanisms and related pharmacology,toxicity and metabolic experiments.
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Objective To analyze changes in the percentages of circulating follicular helper T (Tfh) cells and Tfh subsets in patients with systemic lupus erythematosus (SLE) for better understanding their relationships with SLE , and to investigate effects of steroids on circulating Tfh cells .Methods Pe-ripheral blood mononuclear cells (PBMCs) from 27 patients with SLE (including 10 inactive patients and 17 active patients ) and 21 sex-and age-matched healthy donors were analyzed by flow cytometry to detect the percentage of CD4+CD45RA-CXCR5+Tfh-like cells.Disease activity and the concentration of anti-double-stranded DNA ( anti-dsDNA) antibody were evaluated by SLEDAI score ( SLE disease activity index ) and ELISA, respectively.PBMCs from healthy donors were treated with or without prednisone to evaluate its effects on circulating Tfh cells .Twelve patients with SLE were treated with high-dose steriods ( 200-500 mg/d, 2-3 d) and the percentages of circulating Tfh cells and Tfh subsets in them were analyzed before and after treatment .Results No significant difference in the percentage of circulating Tfh cells was ob-served between patients with SLE and healthy donors (P>0.05), but the percentage of Tfh17 cells in pa-tients with SLE was significantly higher than that in healthy donors (P<0.05).Compared with patients with inactive SLE and healthy donors , patients with active SLE had a lower percentage of Tfh 1 cells (P<0.05).Moreover, the percentage of Tfh1 cells was negatively correlated with SLEDAI score (r=-0.44, P<0.05). The percentage of Tfh2 cells in anti-dsDNA antibody-positive group was significantly higher than that in anti-dsDNA antibody-negative group (P<0.05).In vitro treatment of PBMCs from healthy donors with predni-sone could significantly down-regulate the percentage of circulating Tfh (P<0.01), Tfh1 (P<0.05) and Tfh2 cells (P<0.01), and up-regulate the percentage of Tfh17 cells (P<0.01).In vivo treatment of pa-tients with SLE with steriods could significantly down-regulate the percentage of circulating Tfh (P<0.01), Tfh1 (P<0.05) and Tfh2 cells (P<0.01) and up-regulate the percentage of Tfh17 cells (P<0.01).Con-clusion Abnormal distribution of Tfh subsets is correlated with SLE disease activity and anti -dsDNA anti-body .Steroids in the treatment of SLE could affect the percentage of circulating Tfh cells and the distribution of Tfh subsets .
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Objective To investigate changes in the percentages of circulating and splenic follicular helper T ( Tfh) cells and the significance of Tfh cells in a mouse model of allergic rhinitis .Meth-ods BALB/c mice were sensitized by injection of OVA and aluminum hydroxide to establish the model of allergic rhinitis .Flow cytometry was performed to measure the percentages of circulating and splenic CD 4+CXCR5+after staining Tfh cells with anti-mouse CD4-FITC and anti-mouse CXCR5-PE.Concentrations of OVE-specific IgE ( OVA-sIgE ) in serum samples were measured by enzyme-linked immunosorbent assay ( ELISA ) .Student′s t-test and Pearson ′s correlation analysis were used for statistical analysis .Results Enhanced infiltration of eosinophils in submucosa was observed in the experimental group .After sensitizing the mice with OVA and aluminum hydroxide , the concentration of OVA-sIgE increased from 43 .47 pg/ml [(43.47±2.58) pg/ml] to 50.44 pg/ml [(50.44±1.40) pg/ml] (P=0.029); the percentage of circu-lating CD4+CXCR5+was up-regulated from 6.25％ [(6.25±1.19)％] to 13.94％ [(13.94±2.77)％] (P=0.026); the percentage of splenic CD4+CXCR5+was down-regulated from 18.04％ [(18.04 ± 4.97)％] to 7.26％[(7.26±0.96)％] (P=0.019).The concentration of OVA-specific IgE was posi-tively correlated with the percentage of circulating Tfh cells (r=0.954, P=0.002), but negatively correla-ted with the percentage of splenic Tfh cells (r=-0.801, P=0.028).Moreover, a negative correlation was found between circulating and splenic Tfh cells (r=-0.787, P=0.032).Conclusion Tfh cells might be involved in the immune responses against allergic rhinitis in mice .
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Objective To study the regulation mechanism of bone mesenchymal stem cell (MSC)combined co-translation of islets in differentiation of Follicular Helper T cell (Tfh),and its roll on immunotolerence induction in non-obese diabetic (NOD) mice transplantation model.Methods The NOD mice were divided into 4 groups:Group A with islet transplantation alone;Group B with MSC co-transplantation with islets (MSC:0.5 × 106);Group C with MSC co-transplantation with islets (MSC:2 × 106);Group D with MSC co-transplantation with islets (MSC:3 × 106).ELISA was used to test the expression level of diabetes autoantibody GAD65Ab and IAA.Tfh cell count was detected by FACS.Results The survival time of transplantation groups was much longer in MSCs co-transplantation group than islet-alone group;the level of GAD65Ab,IAA and Tfh cell count were much lower in MSCs co-transplantation group than islet-alone group.Conclusion MSC may protect the islet transplants by regulating the Tfh cell differentiation.
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Understanding germinal center reactions is crucial not only for the design of effective vaccines against infectious agents and malignant cells but also for the development of therapeutic intervention for the treatment of antibody-mediated immune disorders. Recent advances in this field have revealed specialized subsets of T cells necessary for the control of B cell responses in the follicle. These cells include follicular regulatory T cells and Qa-1-restricted cluster of differentiation (CD)8+ regulatory T cells. In this review, we discuss the current knowledge related to the role of regulatory T cells in the B cell follicle.
Subject(s)
Germinal Center , Immune System Diseases , T-Lymphocytes , T-Lymphocytes, Helper-Inducer , T-Lymphocytes, Regulatory , VaccinesABSTRACT
Objective To investigate the effect of interleukin(IL)-21 and dexamethasone(Dex)treatment on the percentage of follicular helper T cells(Tfh)in patients with systemic lupus erythematosus (SLE).Methods Peripheral blood mononuclear cells(PBMCs)obtained from 11 SLE patients were cultured in 96 well plates at 106/well with medium as the control,and with rIL-21(200 ng/μl)or rIL-21(200 ng/μl)+Dex(1×10-6 mol/L)for 24 and 72 hours as the study groups.Another 20 samples were collected and incubated with different concentrations of Dex(0,5×10-7 mol/L,1×10-6 mol/L)for 24 hours.After labeling with CD4,PD1 and CXCR5 monoclonal antibodies,the proportions of Tfh cells were assessed by flow cytometry.ELISA was used to detect supernatant antinuclear antibody(ANA)levels.Differences between groups were analyzed by paired t test.Results The percentages of Tfb cells were elevated when incubated with rIL-21 for 24 h and 72 h[24 h(4.3±1.2)％,(5.9±2.4)％;72 h(5.6±4.0)％,(8.0±5.6)％;t=3.48 and 3.05 respectively,P=0.007 and 0.012].Compared with those in the rIL-21 group,the percentages of Tfh cells in the rIL-21+Dex group were decreased(t=4.70 and 2.78,P=0.001 and 0.019).Tfh cells were decreased ina dose-dependent manner when treated with Dex[24 h(4.2±1.3)％;72 h(6.2±4.4)％;t=3.37 and 2.26,P=0.003 and 0.036].There was no difference of supe(rn)atant ANA levels among those groups.Conclusion IL-21 can promote the proliferation of Tfh cells,while Dex inhibits Tfh cell growth and the inhibition effect is dose dependent.Tfh cells may represent a new target for the treatment of SLE.
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ObjectiveTo study the effect on humoral immunity with combination of CsA and IL-2 fusion protein. MethodsForty C57/B6 mice were evenly divided into four groups,after receiving skin graft from DBA mouse.Mice in the experimental group was given CsA(30 mg/kg,ip) plus IL-2/Fc (1μg,ip) while the control group was only given CsA,each group was given HBV vaccine after skin graft surgery (2 μg,im),while blank group was only given vaccine after skin transplantation.The fourth group were left intact.Fourteen days later,the level of HBSAb,IL-4,IL-10,IFN-γ,IL-2 were measured with ELISA and IL-21and FoxP3 expression level and Tfh percentage of mixed lymphocytes detected. ResultsThe HBSAb level in experimental group is significantly higher than that in the control group and the survival time of skin graft is longer than that in the control group ( F =29.886,P =0.010 ; F =29.772,P =0.011).IL-2,IFN-γ are significantly higher than that in the control group( F =18.156,P =0.0020;F =90.042,P =0.003 ),but the Th2 cytokines such as IL-4,IL-10 are lower ( F =42.102,P =0.009 ; F =23.734,P =0.015 ).The expression level of both IL-21and FoxP3 are significantly higher than control group( F =9.784,P =0.048 ;F =27.883,P =0.012). ConclusionsCombination of CsA and IL-2 fusion protein can significantly enhance the immunogenicity of HBV vaccine and prolong graft survival time.It may be related to the higher expression level of IL-21and FoxP3.