CD4+ T lymphocytes play a major role in regulation of adaptive immunity. Upon activation, naive T cells differentiate into different functional subsets. In addition to the classical Th1 and Th2 cells, several novel effector T cell subsets have been recently identified, including Th17 cells. There has been rapid progress in characterizing the development and function of Th17 cells. Here I summarize and discuss on the genetic controls of their differentiation and emerging evidence on their plasticity. This information may benefit understanding and treating immune diseases.
Animals ; CD4-Positive T-Lymphocytes/cytology/*immunology ; Cell Differentiation ; Cell Lineage ; Cytokines/*genetics ; Epigenesis, Genetic ; Gene Expression Regulation ; Humans ; Interleukin-17/immunology/metabolism ; T-Lymphocytes, Regulatory ; Th1 Cells/immunology ; Th17 Cells/*immunology ; Th2 Cells/immunology ; Transcription Factors/*genetics ; Transcription, Genetic

BACKGROUND: Interleukin-17 (IL-17)-producing T helper (Th) 17 cells are considered as a new subset of cells critical to the development of rheumatoid arthritis (RA). We aimed to investigate the distribution of Th1 and Th17 cells and their association with disease activity, and determine the Th17-related cytokine levels in the peripheral blood of RA patients. METHODS: Peripheral blood mononuclear cells from 55 RA and 20 osteoarthritis (OA) patients were stimulated with mitogen, and the distributions of CD4+Interferon (INF)+IL-17- (Th1 cells) and CD4+INF-IL-17+ (Th17 cells) were examined by flow cytometry. Serum levels of IL-6, IL-17, IL-21, IL-23, and tumor necrosis factor (TNF)-alpha were measured by ELISA. Erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) were recorded. The 28-joint disease activity score (DAS28) was also assessed. RESULTS: The median percentage of Th17 cells was higher in RA patients than in OA patients (P=0.04), and in active than in inactive RA (P=0.03), whereas that of Th1 cells was similar in both groups. Similarly, the levels of IL-17, IL-21, and IL-23 were detected in a significantly higher proportion of RA patients than OA patients and the frequencies of detectable IL-6, IL-17, and IL-21 were higher in active RA than in inactive RA group. The percentage of Th17 cells positively correlated with the DAS28, ESR, and CRP levels. CONCLUSIONS: These observations suggest that Th17 cells and Th17-related cytokines play an important role in RA pathogenesis and that the level of Th17 cells in peripheral blood is associated with disease activity in RA.
Adult ; Aged ; Arthritis, Rheumatoid/blood/metabolism/*pathology ; Blood Sedimentation ; C-Reactive Protein/analysis ; Cytokines/blood ; Female ; Humans ; Male ; Middle Aged ; Osteoarthritis/blood/metabolism/pathology ; Severity of Illness Index ; Th1 Cells/cytology/immunology/metabolism ; Th17 Cells/*cytology/immunology/metabolism

This study was purposed to observe the influence of umbilical cord mesenchymal stem cells (UC-MSC) on the peripheral blood CD4(+)CD25(+)regulatory T cells (Treg), Th17 cells and neutrophils in rats with collagen type II-induced arthritis(CIA), and to explore the regulating effect of UC-MSC transplantation on immunocyte subgroup. The rats wee divided into 3 groups: CIA group (model group), UC-MSC treated group and blank control group. The CIA rats were injected with UC-MSC via tail vein. The percentage of CD4(+)CD25(+) cells in peripheral blood and the expression of NCD11b on neutrophil surface in CIA rates was detected by flow cytometry (FCM), and the serum interleukin-17 (IL-17) was observed by enzyme-linked immunosorbent assay (ELISA). The results showed that the mean fluorescence intensity(MFI) of NCD11b and the level of IL-17 in the model group were significantly higher than those in the blank control group, and the ratio of CD4(+)CD25(+) cells were significantly lower (P < 0.05). The MIF of NCD11b and the level of IL-17 in the UC-MSC treated group were significantly lower than that in the model group (P < 0.05), while the proportion of CD4(+)CD25(+) Treg increased (P < 0.05). Since the fifth week, the above indicators in the UC-MSC group have almostly approached the control group. It is concluded that the UC-MSC can increase peripheral blood Treg proportion in CIA rat, inhibit the secretion of Th17 and the activity of neutrophils, reduce the immune inflammation reaction, decrease the release of proinflammatory factor, and induce immune reconstruction.
Animals ; Arthritis, Experimental ; immunology ; therapy ; Female ; Interleukin-17 ; metabolism ; Mesenchymal Stem Cell Transplantation ; Mesenchymal Stromal Cells ; cytology ; Neutrophils ; immunology ; Rats ; Rats, Sprague-Dawley ; Th17 Cells ; immunology ; Umbilical Cord ; cytology

OBJECTIVE: To investigate the expression levels of Th9, Th17 and Treg cells in peripheral blood of patients with chronic rhinosinusitis with nasal polyps (CRSwNP), and explore the role of Th9, Th17 and Treg cells in the progression of CRSwNP. METHOD: Forty-six cases with CRSwNP served as an experimental group, while 22 cases with simple nasal bleeding or nasal septum deviation served as a control group. The peripheral blood of patients in both groups was collected and analyzed. (1) Using flow cytometry (FCM) to detect the expression rates of Th9, Th17 and Treg cells in peripheral blood. (2) Using qRT-PCR to detect the expression of relevant transcription factor of Th9, Th17 and Treg cells (IL-9mRNA, PU. 1, IRF-4, RoRc, and Foxp3). (3) Using SPSS16.0 to analyse the differentiations and the revelance among these three cells. RESULT: (1) The expression rates of Th9 and Th17 cells in patients with CRSwNP (1.29% ± 0.18%, 4.03% ± 0.69%) was higher than the control group (0.45% ± 0.14%, 1.35% ± 0.26%). But the expression rates of Treg cells in the experimental group (2.98% ± 0.13%) was significantly lower than the control group (5.44% ± 0.57%). The differences were statistically significant (P < 0.05). (2) The expression of revelant transcription factor (IL-9mRNA, PU.1, IRF-4, RoRc) in NP group was also higher than the control group. The expression of Foxp3 in the control group was higher than NP, the differences both were statistically significant (P < 0.05). (3) The difference between Th9 and Th17 in patients with NP was not significant (P > 0.05), and the negative correlation was found between Th17 and Treg (r = -0.549, P < 0.05). CONCLUSION The high expression level of Th9 and Th17 cells might promote the development of NP, whereas the low expression level of Treg cells might further aggravate the occurrence of NP. The main function of the imbalance of Th17/Treg cells may be immune regulation in the pathogenesis of nasal polys.
Case-Control Studies ; Cell Differentiation ; Disease Progression ; Epistaxis ; Flow Cytometry ; Forkhead Transcription Factors ; metabolism ; Humans ; Nasal Polyps ; immunology ; pathology ; Nasal Septum ; abnormalities ; Rhinitis ; immunology ; pathology ; Sinusitis ; immunology ; pathology ; T-Lymphocytes, Regulatory ; cytology ; Th17 Cells ; cytology ; Transcription Factors ; metabolism

OBJECTIVETo explore the effects of emodin in myocardial protection in mice with viral myocarditis (VMC) and explore molecular mechanisms.

METHODSFifty-five male 4-week-old BALB/c mice were randomly divided into control group (n=15), model group (n=20), and emodin group (n=20). The mice in model and emodin groups were inoculated with 0.1 ml Eagle's solution containing coxsackievirus B3 intraperitoneally, and those in the control group were given only 0.1 ml Eagle's solution. From the day of inoculation, the mice in emodin group received intragastric administration with 0.1 ml of 3 mg/ml emodin solution once daily for 21 consecutive days, and those in the control and model groups received 0.1 ml distilled water only. On day 7 after inoculation, 5 mice from each group were sacrificed to determine the viral titers in the cardiac tissues. All the mice were sacrificed on day 22 for measurement of the heart weight and histopathological inspection of the heart with HE staining. The mRNA and protein expression levels of myocardial interleukin-23 (IL-23) and interleukin-17 (IL-17) were detected by real-time quantitative PCR and Western blotting, respectively, and serum IL-23 and IL-17 levels were examined using enzyme linked immunosorbent assay (ELISA). Th17 cell frequencies were analyzed by flow cytometry. The expression levels of myocardial nuclear factor-κB (NF-κB) p65 in the cardiomyocyte nuclei were examined using Western blotting, and myocardial interleukin (IL)-1β, IL-6 and tumor necrosis factor-α (TNF-α) contents were detected by ELISA.

RESULTSThe mortality, myocardial histopathologic scores and virus titers in emodin group were all significantly lower than those in the model group (P<0.05). The heart-to-body weight ratio, myocardial IL-23 and IL-17 expressions, serum IL-23 and IL-17 levels, Th17 cell frequencies, cardiomyocyte nuclear NF-κB p65 expression, and myocardial contents of IL-1β, IL-6 and TNF-α were all significantly increased in the model group as compared to the control group (P<0.01) but reduced significantly in emodin group as compared to model group (P<0.05).

CONCLUSIONEmodin can protect against VMC by inhibiting IL-23/IL-17 inflammatory axis, Th17 cell proliferation and viral replication in mice.

Animals ; Coxsackievirus Infections ; immunology ; Cytokines ; immunology ; Emodin ; pharmacology ; Enterovirus ; physiology ; Interleukin-17 ; immunology ; Interleukin-23 ; immunology ; Male ; Mice ; Mice, Inbred BALB C ; Myocarditis ; immunology ; virology ; Th17 Cells ; cytology ; drug effects ; Transcription Factor RelA ; metabolism ; Virus Replication

OBJECTIVETo investigate the effect of oral administration of Zaocys type II collagen (ZCII) on the percentages of Treg/Th17 cells in mesenteric lymph node lymphocytes (MLNLs) in mice with collagen-induced arthritis (CIA).

METHODSCIA was induced in male C57BL/6 mice by immunization with chicken type II collagen. Three weeks later, ZCII, purified by pepsin digestion, was orally administered in the mice for 7 consecutive days (daily dose of 10, 20, or 40 µg/kg). The severity of arthritis in each limb was evaluated using a macroscopic scoring system, and histopathological changes of the joint were observed microscopically with HE staining. The percentages of Treg and Th17 cells in MLNLs was detected by flow cytometry, and the levels of transforming growth factor-β (TGF-β) and interleukin-17 (IL-17) in the supernatant of MLNLs were measured by enzyme-linked immunosorbent assay.

RESULTSCompared with normal control mice, the mice with CIA had significantly higher scores for arthritis and histopathological changes, with also significantly increased percentages of Treg and Th17 cells in MLNLs and elevated levels of TGF-β and IL-17 in MLNL supernatant (P<0.05). In ZCII peptide-treated mice, the scores for arthritis and histopathological changes were significantly lower than those in CIA model group (P<0.05), and Treg cell percentage in MLNLs was up-regulated while Th17 cell percentage lowered; the level of TGF-β was increased but IL-17 was decreased significantly (P<0.05).

CONCLUSIONOral administration of ZCII improves CIA in mice by regulating the percentages of Treg/Th17 cells and the cytokine levels in MLNLs, suggesting the value of ZCII as a promising candidate agent for treatment of rheumatoid arthritis.

Animals ; Arthritis, Experimental ; immunology ; Arthritis, Rheumatoid ; Collagen Type II ; pharmacology ; Enzyme-Linked Immunosorbent Assay ; Flow Cytometry ; Interleukin-17 ; metabolism ; Lymph Nodes ; cytology ; Male ; Mice ; Mice, Inbred C57BL ; T-Lymphocytes, Regulatory ; immunology ; Th17 Cells ; immunology ; Transforming Growth Factor beta ; metabolism

Myeloid-related protein (MRP)8/MRP14 is an endogenous Toll-like receptor 4 (TLR4) ligand and is abundant in synovial fluid (SF) of rheumatoid arthritis (RA) patients. Belonging to damage-associated molecular patterns, it amplifies proinflammatory mediators and facilitates a wide range of inflammatory and autoimmune diseases. Interleukin (IL)-17-producing T-helper (Th)17 cells have a crucial role in RA pathogenesis, and IL-6 is the key factor promoting Th17 differentiation. We investigated whether the level of MRP8/MRP14 is positively associated with IL-6 and IL-17 levels in RA SF and found that MRP8/MRP14 level had a significant correlation with IL-6 and IL-17 levels in RA SF. We also observed that MRP8-induced IL-17 production by peripheral blood mononuclear cells but MRP14 did not. Upon stimulation with MRP8, IL-6 production was enhanced by RA fibroblast-like synoviocytes (FLS) and was further elevated by coculturing RA FLS with activated CD4+ T cells. Moreover, we demonstrated that MRP8-activated IL-6 production by RA FLS promoted differentiation of Th17 cells using the coculture system consisting of CD4+ T cells and RA FLS. In addition, IL-6 blockade attenuated Th17 polarization of CD4+ T cells in the cocultures. Inhibitor studies revealed that MRP8 increased IL-6 production in RA FLS via TLR4/phosphoinositide 3-kinase/nuclear factor-kappaB and mitogen-activated protein kinase signaling pathways. Our results show that MRP8 has a crucial role in stimulating IL-6 expression by RA FLS, and subsequently promotes Th17 differentiation in RA, suggesting that neutralizing MRP8 level in RA synovium may be an effective therapeutic strategy in RA treatment.
ATP-Binding Cassette Transporters/*metabolism ; Adult ; Aged ; Arthritis, Rheumatoid/*pathology ; CD4-Positive T-Lymphocytes/metabolism ; Calgranulin B/metabolism ; Cell Differentiation/*immunology ; Fibroblasts/*metabolism/pathology ; Humans ; Inflammation Mediators/metabolism ; Interleukin-17/metabolism ; Interleukin-6/*biosynthesis ; Middle Aged ; Signal Transduction/immunology ; Synovial Fluid/cytology ; Synovial Membrane/metabolism/pathology ; Th17 Cells/*pathology ; Toll-Like Receptor 4/metabolism ; *Up-Regulation

Astragalus membranaceus may be a potential therapy for childhood asthma but its driving mechanism remains elusive. The main components of A. membranaceus were identified by HPLC. The children with asthma remission were divided into two combination group (control group, the combination of budesonide and terbutaline) and A. membranaceus group (treatment group, the combination of budesonide, terbutaline and A. membranaceus). The therapeutic results were compared between two groups after 3-month therapy. Porcine peripheral blood mononuclear cells (PBMCs) were isolated from venous blood by using density gradient centrifugation on percoll. The levels of FoxP3, EGF-β, IL-17 and IL-23 from PBMCs and serum IgE were measured. The relative percentage of Treg/Th17 cells was determined using flow cytometry. The main components of A. membranaceus were calycosin-7-O-glucoside, isoquercitrin, ononin, calycosin, quercetin, genistein, kaempferol, isorhamnetin and formononetin, all of which may contribute to asthma therapy. Lung function was significantly improved in the treatment group when compared with a control group (P < 0.05). The efficacy in preventing the occurrence of childhood asthma was higher in the treatment group than the control group (P < 0.05). The levels of IgE, IL-17 and IL-23 were reduced significantly in the treatment group when compared with the control group, while the levels of FoxP3 and TGF-β were increased in the treatment group when compared with the control group (P < 0.05). A. membranaceus increased the percentage of Treg cells and reduced the percentage of Th17 cells. A. membranaceus is potential natural product for improving the therapeutic efficacy of combination therapy of budesonide and terbutaline for the children with asthma remission by modulating the balance of Treg/Th17 cells.
Animals ; Asthma ; drug therapy ; immunology ; Astragalus propinquus ; chemistry ; Budesonide ; administration & dosage ; Cells, Cultured ; Child ; Child, Preschool ; Cytokines ; metabolism ; Drugs, Chinese Herbal ; administration & dosage ; pharmacology ; Female ; Humans ; Immunologic Factors ; administration & dosage ; pharmacology ; Leukocytes, Mononuclear ; drug effects ; metabolism ; Lung ; drug effects ; physiology ; Male ; Swine ; T-Lymphocytes, Regulatory ; cytology ; drug effects ; Terbutaline ; administration & dosage ; Th17 Cells ; cytology ; drug effects ; Treatment Outcome

OBJECTIVETo explore the role of Th17 cells, CD4⁺ CD25⁺ regulatory Treg cells (Treg) and its transcription factor RORγt and FoxP3 in the pathogenesis of children with Henoch-Schonlein purpura (HSP) so as to provide a new strategy for treatment of children with Henoch-Schonlein purpura by regulating the balance of Th17 and Treg cells.

METHODSForty children with Henoch-Schonlein purpura in acute phase admitted in our hospital from February 2012 to March 2013 were enrolled in this study, forty healthy children were simultaneously used as controls. The expression of RORγt mRNA and FoxP3 mRNA in peripheral blood mononuclear cells was detected by real-time PCR using SYBR Green I. The levels of IL-17A, TGF-β1, IL-2 and IL-6 in serum were measured by ABC-ELISA. The ratio of Th17 cells to Treg cells in peripheral blood T lymphocytes was detected by flow cytometry.

RESULTSThe levels of Th17 cells (2.75 ± 0.60%) and RORγt mRNA (1.11 ± 0.51) in HSP group were significantly higher than levels of Th17 cells (1.41 ± 0.29%) and RORγt mRNA (0.65 ± 0.24) (P < 0.01) in control group, but the levels of Treg cells (4.56 ± 1.26%) and FoxP3 mRNA (1.15 ± 0.45) in HSP group were lower than those of Treg cells (7.85 ± 1.97%) and FoxP3 mRNA (2.32 ± 1.1) (P < 0.01) in the control group. The relative levels of serum IL-17A, IL-6, TGF-β1 (40.40 ± 11.81 pg/ml, 75.38 ± 27.19 pg/ml, 309.41 ± 81.03 pg/ml) in the HSP group were significantly higher than those in the control group [IL-17A (20.32 ± 10.70 pg/ml), IL-6 (25.16 ± 8.31 pg/ml), TGF-β1 (236.34 ± 66.01 pg/ml)] (P < 0.01), but the level of serum IL-2 (25.60 ± 13.19 pg/ml) in the HSP group was lower than that (34.42 ± 11.69 pg/ml) in the control group (P < 0.01). The further detection demonstrated that in the children with acute HSP, the expression of Th17 cells positively correlated with RORγt mRNA, IL-17A and IL-6 with the correlation coefficients of 0.887, 0.938 and 0.934 (P < 0.01), respectively. The positive correlation was also shown between the Treg cells and FoxP3 mRNA, IL-2 with the correlation coefficients of 0.834 and 0.932 (P < 0.01), respectively.

CONCLUSIONThere are higher expression levels of Th17 cells, RORγt mRNA and IL-17A, and lower expression levels of Treg cells, FoxP3 mRNA of children with HSP in acute phase, which shows that Th17/Treg imbalance exists in children with HSP in acute phase. The levels of serum IL-6, TGF-β1 increase and the serum IL-2 decrease in children with HSP in acute phase, moreover, there are the positive correlations between the levels of Th17 cells and expression of IL-6, as well as the level of Treg cells and expression of IL-2 in children with HSP in acute phase.

Case-Control Studies ; Child ; Flow Cytometry ; Forkhead Transcription Factors ; metabolism ; Humans ; Interleukin-17 ; blood ; Interleukin-2 ; blood ; Interleukin-6 ; blood ; Leukocytes, Mononuclear ; Nuclear Receptor Subfamily 1, Group F, Member 3 ; metabolism ; Purpura, Schoenlein-Henoch ; immunology ; RNA, Messenger ; Real-Time Polymerase Chain Reaction ; T-Lymphocytes, Regulatory ; cytology ; Th17 Cells ; cytology ; Transforming Growth Factor beta1 ; blood

To determine the impact of IL-23 knockdown by RNA interference on the development and severity of ovalbumin (OVA)-induced asthmatic inflammation, and the potential mechanisms in mice, the IL-23-specific RNAi-expressing pSRZsi-IL-23p19 plasmid was constructed and inhaled into OVA-sensitized mice before each challenge, as compared with that of control mice treated with alum or budesonide. Inhalation of the pSRZsi-IL-23p19, significantly reduced the levels of OVA-challenge induced IL-23 in the lung tissues by nearly 75%, determined by RT-PCR. In addition, knockdown of IL-23 expression dramatically reduced the numbers of eosinophils and neutrophils in BALF and mitigated inflammation in the lungs of asthmatic mice. Furthermore, knockdown of IL-23 expression significantly decreased the levels of serum IgE, IL-23, IL-17, and IL-4, but not IFNgamma, and its anti-inflammatory effects were similar to or better than that of treatment with budesonide in asthmatic mice. Our data support the notion that IL-23 and associated Th17 responses contribute to the pathogenic process of bronchial asthma. Knockdown of IL-23 by RNAi effectively inhibits asthmatic inflammation, which is associated with mitigating the production of IL-17 and IL-4 in asthmatic mice.
Animals ; Asthma/chemically induced/genetics/metabolism/*prevention & control ; Bronchoalveolar Lavage Fluid/cytology ; Enzyme-Linked Immunosorbent Assay ; Eosinophils ; Female ; Inflammation/metabolism ; Interleukin-23/*genetics ; Leukocyte Count ; Mice ; Mice, Inbred BALB C ; Neutrophils ; Ovalbumin/pharmacology ; Plasmids/genetics ; *RNA Interference ; RNA, Small Interfering/*genetics ; Reverse Transcriptase Polymerase Chain Reaction ; Th17 Cells/immunology