Effects of Yangxue-Jiedu decoction on imiquimod-induced psoriasis-like lesions in STAT3 transgenic mice

AIM: To observe the effects of Yangxue-Jiedu (YXJD) decoction on imiquimod-induced psoriasis-like lesions in STAT3 transgenic mice.METHODS: STAT3 transgenic mice (n=24) were randomly divided into 4 groups: control group (using purified water for oral administration), model group (topical 5% imiquimod 42 mg and using purified water for oral administration), YXJD groups (topical 5% imiquimod 42 mg and using YXJD decoction for oral administration), and methotrexate (MTX) group (1 mg/kg MTX solution for oral administration, with the same topical imiquimod as model group). On day 7, the skin lesions were collected for examination. The lesions were evaluated according to the psoriasis area and severity index (PASI). The skin barrier function was evaluated by assessing oil and water components in the skin. The inflammation of psoriasis-like lesions was assessed by histological method. The expression of proliferating cell nuclear antigen (PCNA) and CD3 was assessed by immunohistochemical staining. The mRNA expression of IL-17A, IL-17C, IL-22 and RORγt was detected by real-time PCR. The levels of JAK/STAT3 pathway-related proteins in isolated T cells were determined by Western blot.RESULTS: Administration of YXJD decoction inhibited imiquimod-induced keratinocyte proliferation and infiltration of CD3⁺ T cells in psoriatic lesions, and ameliorated the epidermal barrier by up-regulation of the oil and water components in psoriatic lesions. Meanwhile, administration of YXJD decoction improved the systemic immune responses by reducing the weight of the spleen. The inflammatory cytokines IL-17A, IL-17C, IL-22 and RoRγt, and the levels of JAK/STAT3 pathway-related proteins STAT3, p-STAT3, JAK3 and p-JAK3 were decreased by administration of YXJD decoction.CONCLUSION: YXJD decoction likely alleviates imiquimod-induced psoriasis-like lesions in the STAT3 transgenic mice by inhibiting the phosphorylation of STAT3, and reducing the expression of IL-17A, IL-17C, IL-22 and RORγt.     

Effects of Yangxue decoction and Yangxue-Jiedu decoction on imiquimod-induced psoriasis-like mouse model

AIM: To investigate and compare the effects of Yangxue (YX) decoction and Yangxue-Jiedu (YXJD) decoction on psoriasis-like mouse skin lesions. METHODS: BALB/c mice (n=50) were randomly divided into control group, model group, methotrexate (MTX) group, YX group and YXJD group (10 mice in each group). The psoriasis-like mouse model was induced by topical application of imiquimod cream on the back. The skin water/oil test pen was used to detect the water/oil content of the skin in the back of the mice. The pathological changes of the lesions were observed by HE staining and the thickness of the epidermis was measured. The immunohistochemical staining was used to observe the skin lesions, and the mRNA expression levels of interleukin (IL)-17, IL-23 and IL-1β in skin lesions were detected by real-time PCR. RESULTS: The skin lesions in YX, YXJD and MTX group were better than those in model group, with lower psoriasis area and severity index (PASI) score and skin thickness. The skin water/oil content in YXJD group was higher than that in model group (P<0.05). The expression of proliferating cell nuclear antigen (PCNA) and the positive expression of CD3⁺ T cells in the skin of YXJD group were lower than those in YX group, and the skin thickness was lower than that in YX group (P<0.05). The results of real-time PCR showed that relative mRNA expression of IL-17, IL-23 and IL-1β in YX group and YXJD group was lower than that in model group (P<0.05), and the relative mRNA expression of IL-1β in YXJD group was lower than that in YX group. Administration of YXJD decoction showed better therapeutic effect than MTX. CONCLUSION: YX decoction and YXJD decoction relieve imiquimod-induced skin lesions by reducing immune response. Meanwhile, the effect of YXJD decoction is better than that of YX decoction.     

Role of Th17/IL-17A in chronic inflammatory airway diseases

The idea has been popular for a long time that Th1/Th2 imbalance is the major cause of many diseases. However, the Th1/Th2 paradigm has encountered increasing challenge since the discovery of a novel subset of Th cells, Th17. Th17 cells secrete a series of cytokines (IL-17A~F, IL-21 and IL-22), which is quite different from those produced by Th1 and Th2 cells. It is now generally accepted that Th17/IL-17A plays a pivotal role in autoimmune and host defense. Although first discovered in autoimmune diseases, emerging studies begin to explore the way in which Th17/IL-17A acts in chronic inflammatory airway diseases, such as asthma and chronic obstructive pulmanary disease. In this review, we will summarize the differentiation and function of Th17, and introduce the progress in the correlation between Th17/IL-17A and chronic inflammatory airway diseases. Further elucidating the mechanism of Th17/IL-17A-related pathophysiological changes will contribute to prevention and treatment of chronic inflammatory airway diseases.     

Inhibitory effects of paeonol on keratinocyte viability,cytokines secretion stimulated by IL-17A via STAT3 signaling pathway

AIM To observe the effect of paeonol on interleukin-17A （IL-17A）-induced human keratinocyte viability, cytokine secretion, and related signal transduction pathways. METHODS In vitro HaCaT cells stimulated by IL-17A （200 μg/L） were co-cultured with paeonol （200 mg/L and 100 mg/L） for 24 h. The cell viability was measured by CCK-8 assay. The Th1/Th2/Th17 cytokine （including IL-6, etc.） levels were measured by cytometric bead array assay. The IL-23 level was measured by ELISA. The mRNA expression of IL-23, IL-6, CXCL2, CXCL8, CCL20 and STAT3 was detected by real-time PCR, and Western blot was used to determine the protein levels of STAT3 and ERK1/2. RESULTS Paeonol significantly inhibited IL-17A-induced HaCaT cell viability （P<0.05）, as well as reduced IL-6 level. Meanwhile, paeonol decreased mRNA levels of IL-23, CXCL2, CXCL8, and CCL20. Paeonol also inhibited the expression of STAT3 at mRNA and protein levels. However, no significant effect of paeonol on ERK1/2 protein expression was observed. CONCLUSION Paeonol inhibits HaCaT cell viability and cytokine secretion induced by IL-17A, and its mechanism might be related to STAT3 singaling pathway.     

Effect of Liang Xue Huo Xue capsules on mouse psoriasis-like lesions induced by imiquimod

AIM: To observe the effects of Liang Xue Huo Xue (LXHX) capsules on mouse psoriasis-like lesions induced by imiquimod (IMQ). METHODS: BALB/c female mice (n=48) were randomly divided into 6 groups: normal group, model group, LXHX capsules groups with high, medium or low doses, and glycosides of Tripterygium wilfordii (GTW) group. On day 8, skin lesions were determined by pathological examination. The lesions were evaluated according to the psoriasis area and severity index (PASI). The histology and epidermal thicknesses were observed under light microscope. The expression of proliferating cell nuclear antigen (PCNA) was detected by immunohistochemical staining. Meanwhile, the positive expression of CD3, CD11c, F4/80, CD31 and Gr-1 was counted by immunohistochemical staining. RESULTS: Compared with model group, the cutaneous symptoms in LXHX capsules groups were alleviated, with PASI scores decreased, epidermal parakeratosis and epidermal over-proliferation relived, the numbers of dermal T lymphocytes, dendritic cells, macrophages, neutrophils and monocytes reduced significantly. CONCLUSION: LXHX capsules improve imiquimod-induced mouse psoriasis-like lesions by inhibiting over-proliferation of keratinocytes, parakeratosis, inflammatory infiltration and angiogenisis.     

Change of intestinal flora and its relationship with IL-23/IL-17 axis in patients with ulcerative colitis

AIM:To investigate the change of intestinal flora distribution and its relationship with interleukin-23 (IL-23)/IL-17 axis in ulcerative colitis (UC) patients. METHODS:The fresh fecal samples from 20 patients with active UC and 20 healthy controls were collected. The distribution of the flora was analyzed by direct smear and traditional bacterial culture. The changes of bacteria were detected by real-time PCR. The hemoglobin, albumin, erythrocyte sedimentation, and C-reactive protein levels were tested routinely. Both normal and damaged mucosal tissues of UC patients were examined and obtained by colonoscopy, and further assessed by Mayo scoring, Baron grading and HE staining. The expression of IL-17 and IL-23 was observed by immunohistochemistry and Western blot. RESULTS:(1) The degree of flora imbalance in active UC patients was higher than that in the healthy controls (P<0.05). (2) The results of aerobic culture showed that the number of Escherichia coli in the UC patients was significantly lower than that in the normal controls (P<0.01), while Enterococcus was increased obviously (P<0.01). The results of anaerobic culture revealed that the numbers of Bacteroidetes, Bifidobacterium bifidum and Lactobacilli in the UC patients were significantly decreased (P<0.01). (3) Quantitative analysis of target bacteria showed that the relative quantification of Escherichia coli, Bacteroidetes, Bifidobacterium bifidum and Lactobacilli in the UC patients was significantly lower than that in the normal subjects, and the number of Enterococcus was significantly increased (P<0.01). (4) Compared with control group, no significant change of hemoglobin in the UC patients was ovserved, albumin was significantly decreased (P<0.05), but erythrocyte sedimentation and C-reactive protein levels were elevated obviously (P<0.01). (5) The Mayo score, Baron grade, and histopathological score were all increased (P<0.01). (6) High IL-17 and IL-23 expression levels were detected in the UC patients (P<0.01). (7) Correlation analysis showed that the average absorbance values of IL-17 and IL-23 expression were positively correlated with Baron grade (r=0.717, P=0.02; r=0.849, P=0.016) and pathological score (r=0.660, P=0.03; r=0.675, P=0.032). Meanwhile, the average absorbance value of IL-23 expression was negatively correlated with the number of Escherichia coli (r=-0.699, P=0.025), and positively correlated with Enterococcus (r=0.872, P=0.010). Furthermore, the average absorbance value of IL-17 expression was positively correlated with Enterococcus (r=0.764, P=0.046), and both of them were not correlated with other bacteria. CONCLUSION:Obvious flora imbalance exists in active UC patients, changed intestinal microflora is closely related with the degree of inflammation. IL-23/IL-17 axis, as a key factor in the development of UC, may be related to the changes of intestinal microflora. The interaction between intestinal microflora and IL-23/IL-17 axis plays an important role in the pathogenesis of UC.     

Effect of 1α, 25-dihydroxyvitamin D3 on T helper cell 17 and expression of related cytokines in penetrating keratoplasty in mice

AIM: To evaluate the effects of 1α, 25-dihydroxyvitamin D3 on T helper cell 17 (Th17 cells) and its related cytokines in a mouse model of corneal allograft transplantation. METHODS: C57BL/6 mice were transplanted with corneal grafts from BALB/c mice and treated intraperitoneally with 1.0 μg 1α, 25-dihydroxyvitamin D3 or soybean oil every other day after operation. The transparency of the corneal grafts was evaluated for potential rejection signs by slit lamp biomicroscopy and histopathology. The expression levels of IL-17, RORγt and IFN-γ in the spleen were measured by real-time PCR. Moreover, the protein expression of RORγt and IL-17 in the peripheral blood was analyzed by Western blotting. IL-17 and IFN-γ in peripheral blood were measured by flow cytometry. RESULTS: 1α, 25-dihydroxyvitamin D3 significantly inhibited the rejection of the corneal allograft and reduced the numbers of inflammatory infiltrates in the corneal graft. In the spleen, 1α, 25-dihydroxyvitamin D3 treatment reduced the expression levels of IL-17, RORγt and IFN-γ. In the peripheral blood, 1α, 25-dihydroxyvitamin D3 treatment downregulated the expression levels of RORγt, IL-17 and IFN-γ. CONCLUSION: The effects of 1α, 25-dihydroxyvitamin D3 on suppressing corneal transplantation-induced allograft rejection in mice are closely associated with its modulation on IL-17 and related cytokine RORγt.     

Effects of Xiaoyaosan on imiquimod induced psoriatic lesions and depression neurotransmitters in mouse model

AIM: To observe the effect of Xiaoyaosan decoction on the psoriatic lesions and depression neurotransmitters induced by imiquimod in mice. METHODS: BALB/c male mice were randomly divided into control group, model group, methotrexate group and Xiaoyaosan high, medium and low dose groups, 6 mice in each group. Imiquimod (IMQ, 5%) was used on the back of the animals to induce psoriasis-like lesions in the mice. The psoriasis area and seve-rity index (PASI) were evaluated for daily scoring. The sugar water preference experiment was conducted to explore the behavioral differences in the mice. The morphological changes and epidermal thickness of the lesions were observed under light microscopy. Immunohistochemical method was used to detect the expression of CD3 on T lymphocyte surface. The expression of Ki67 in the skin lesions was detected by immunofluorescence. The contents of monoamine neurotransmitters such as adrenaline (AD), gamma-aminobutylic acid (GABA), glutamate (Glu), dopamine (DA) and their metabolites in the hippocampus and hypothalamus of mice were detected by high performance liquid chromatography-mass spectrometry (HPLC-MS). RESULTS: Compared with model group, the back skin lesions of Xiaoyaosan each dose group and methotrexate group were significantly improved, and the PASI score and epidermal thickness were both lower than those in model group (P<0.05). The expression levels of Ki67 and CD3⁺ T cells in Xiaoyaosan group and methotrexate group were lower than those in model group (P<0.05). Compared with model group, the body mass change range of Xiaoyaosan high-dose group and blank control group was significantly smaller than that in model group (P<0.05). The sugar water preference rate in blank control group was significantly higher than that in model group (P<0.01). Compared with model group, the sugar water preference rate in methotrexate and Xiaoyaosan groups showed a certain increase trend, but no statistical diffe-rence was observed. Compared model group, the levels of 3, 4-Dihydroxypheny-lacetic acid (DOPAC), AD, GLU and GABA levels in the mouse hippocampus in blank control group were decreased significantly (P<0.01), while the levels of DA and homovanillic acid (HVA) had no significant difference (P>0.05). No significant difference of DA, DOPAC, HVA and GLU levels in the mouse hypothalamus was observed between blank control group and model group (P>0.05), while the content of AD and GABA in the mouse hypothalamus in blank control group was lower than that in model group. The AD content of the hypothalamus in high-dose Xiaoyaosan group was significantly higher than that in model group (P<0.01), and the HVA content of the hypothalamus in low-dose Xiaoyaosan group was significantly higher than that in model group (P<0.01). PASI score was negatively correlated with the content of DOPAC, AD, GLU and GABA in the hippocampus and the content of AD, GLU and GABA in the hypothalamus, those were, the more severe the back skin lesion was, the lower the expression of depression-related neurotransmitters were, indicating the aggravation of depression in the mice. CONCLUSION: Xiaoyaosan improves the skin lesions induced by imiquimod in the mice with psoriasis, improves the behavior of depression in the mice with psoriasis, and up-regulates the expression of depression-related monoamine neurotransmitters. The expression of depression-related neurotransmitters is negatively correlated with the skin lesions induced by imiqumod in the mice with psoriasis. The degree of depression is increased with the aggravation of psoriatic lesions.     

Relationship between Th17 cells infiltrated in lungs and pulmonary vascular reconstruction under hypobarric hypoxia

AIM: To investigate the changes of retinoid-related orphan receptor γt(RORγt) mRNA and interleukin-17(IL-17) protein in the lung tissue under hypobaric hypoxia, and the relationship between Th17 cells and hypoxic pulmonary vascular reconstruction. METHODS: Male BALB/c mice(n=50) were randomly divided into control group and 3 d, 7 d, 14 d and 28 d hypobaric hypoxia groups. The mice in hypobaric hypoxia groups were housed in a hypobaric hypoxia chamber(simulated altitude of 6 000 m) for 3 d, 7 d, 14 d or 28 d. The mice in control group were housed in normal pressure and oxygen environment. The hemodynamic data were recorded by cardiac catheterization. The hypertrophy of right ventricle was evaluated by the ratio of weight of the right ventricle to the weight of the left ventricle plus interventri-cular septum, and the right ventricular weight over body weight. The spleen was collected and the proportions of the Th17(CD4⁺IL-17⁺RORγt⁺) cells were detected by flow cytometry. The serum levels of IL-4, IL-6 and IL-17 and the change of IL-17 in the lung tissue were measured by ELISA. The mRNA expression of RORγt in the spleen and lung tissues was measured by RT-qPCR. RESULTS: Compared with control group, the mouse right ventricular systolic pressure, the hypertrophy index of right ventricle and the serum IL-17 level were significantly elevated in hypoxia groups, which was consistent with the results of flow cytometry. The mRNA expression of RORγt in the lung tissue was also significantly increased in 7 d, 14 d and 28 d hypoxia groups. The expression of IL-17 in the lung tissue was significantly increased in 14 d and 28 d hypoxia groups. CONCLUSION: Hypoxia promotes differentiation of Th0 cells to Th17 cells in the spleen. The Th17 cells infiltrated in the lung tissue under hypobarric hypoxia are involved in pulmonary vascular reconstruction.     

Diagnostic value of Th17 cells in symptom severity and prognosis of chronic obstructive pulmonary disease

AIM: To observed the correlation between Th17 cell level and the symptom severity and prognostic factors of chronic obstructive pulmonary disease (COPD), and to explore the clinical application value of Th17 cell level in assessing the prognosis of patients with COPD. METHODS: The patients with diagnosed COPD (n=110) in our hospital during May 2013 to December 2014, and 40 healthy subjects were enrolled in the study. According to the Global Initiative for Chronic Obstructive Lung Disease (GOLD), the COPD patients were divided into group A (low risk, less symptoms), group B (low risk, more symptoms), group C (high risk, less symptoms) and group D (high risk, more symptoms), which were given inhaled corticosteroid/long-acting β₂ agonist or corticosteroid/long-acting β₂ agonist+long-acting antimuscarinic agent treatment for 3 months. The proportion of Th17 cells, cytokines (IL-17 and IL-6), the COPD assessment test (CAT) score, age, body mass index, pulmonary function and the times of acute exacerbation of COPD in previous 1 year were observed before and after treatment. The correlation analysis between the level of Th17 cells and other clinical characteristics was performed. RESULTS: Th17 cell, IL-17 and IL-6 levels in COPD group were significantly higher than those in control group (P < 0.05). With the increase in the severity of COPD symptoms, Th17 cells, cytokines (IL-17 and IL-6) and CAT score in groups B and D were significantly higher than those in groups A and C (P < 0.05). The univariate analysis showed that the levels of Th17 cells in groups B and D before treatment were positively correlated with the CAT score (P < 0.05), which were negatively correlated with FEV₁ , FEV₁% Pred, FVC and FVC% Pred. The levels of Th17 cells were not correlated with the CAT score, FEV₁, FEV₁% Pred, FVC and FVC% Pred in groups A and C. The levels of Th17 cells after treatment were positively correlated with the CAT score, which were negatively correlated with FEV₁ , FEV₁% Pred, FVC and FVC% Pred (P < 0.05). CONCLUSION: The peripheral Th17 cell level has a good correlation with IL-17, IL-6, CAT score and pulmonary function in COPD patients, suggesting a potential value to predict the symptom severity and prognosis of COPD.     

Immunomodulatory effect of human umbilical cord mesenchymal stem cells with interleukin-17 receptor-like molecule overexpression on spleen lymphocytes from mice with trinitrobenzene sulfonic acid-induced colitis

AIM: To investigate the immunomodulatory effect of human umbilical cord mesenchymal stem cells with interleukin-17 receptor-like molecule overexpression (IL-17RLM-hUCMSCs) on the spleen lymphocytes from the mice with trinitrobenzene sulfonic acid (TNBS)-induced colitis for providing optimal seed cells to treat inflammatory bowel disease. METHODS: Mesenchymal stem cells were isolated from human umbilical cord. The IL-17RLM gene was transferred into mesenchymal stem cells by lentivirus vector to establish IL-17RLM-hUCMSCs. The experimental colitis mice were induced by TNBS enema, and the spleen lymphocyte suspension was isolated. The lymphocytes were co-cultured with different concentrations of IL-17RLM-hUCMSCs and hUCMSCs under the stimulation of concanavalin A (ConA) for 72 h. The proliferation of lymphocytes was detected by the methods of CCK8 assay and CFSE labeling with lymphocytes+ConA as positive control. The changes of lymphocyte subsets (Th1, Th2, Th17 and Treg) were examined by flow cytometry.RESULTS: Both hUCMSCs and IL-17RLM-hUCMSCs inhibited T-cell proliferation in vitro co-culture system (P < 0.05). When the ratios of MSCs to lymphocytes ranged from 1:1 to 1:10, the inhibitory rates were in a dose-dependent manner. IL-17RLM-hUCMSCs showed higher inhibitory rate than hUCMSCs within the effective concentration range (P < 0.05). Both hUCMSCs and IL-17RLM-hUCMSCs reduced the proportions of Th1 and Th17 cell subsets and increased Treg cell population of spleen lymphocytes from TNBS-induced colitis mice, and IL-17RLM-hUCMSCs showed a stronger inhibitory effect on Th17 cell subset (P < 0.05). CONCLUSION: IL-17RLM-hUCMSCs remarkably inhibit the proliferation of spleen lymphocytes from TNBS-induced colitis mice in a dose-dependent manner. Meanwhile, they regulate immune balance of T cells and have stronger inhibitory effect on Th17 subset.     

The effect and mechanism of H. polygyrus infection in T-cell-mediated inflammatory bowel disease in mice

AIM: To investigate the effect and mechanism of Heligmosomoides polygyrus (H. polygyrus) infection in mouse inflammatory bowel disease (IBD) mediated by CD4⁺ helper T-cells. METHODS: Ovalbumin (OVA) -specific CD4⁺ helper T-cells were transferred into SCID (severe combined immunodeficiency) mice to establish an IBD model. The IBD mice were infected by H. polygyrus and sacrificed 14 days later. The histological changes of the colon were observed, and the expression of interferon-gamma (IFN-γ) and interleukin-4 (IL-4) in mesenteric lymph nodes was detected by ELISA and flow cytometry. Additionally, IL-4 monoclonal antibody was intraperitoneally injected into the H. polygyrus-infected IBD mice to block the secretion of IL-4. The IL-4-blocking IBD mice were sacrificed 9 days later and the above indexes were also determined.RESULTS: Compared with the non-infection group, the H. polygyrus-infected IBD mice had more severe colonic lesions, higher level of IL-4 and lower level of IFN-γ in mesenteric lymph nodes (all P<0.05). Compared with the non-blocking group, the H. polygyrus-infected IBD mice with IL-4 blockage had less colonic lesions, lower IL-4 level and higher IFN-γ level (all P<0.05).CONCLUSION: H. polygyrus infection in CD4⁺ T-cell-mediated IBD model promotes inflammation in the early stage probably by inducing the secretion of Th2 cytokine and inhibiting the secretion of Th1 cytokine. The finding suggests that using worms for treatment of IBD needs to be cautious.     

Effect of tetramethylpyrazine on paw MMP-13 protein expression and serum VEGF,IL-17 and IL-23 levels in rats with collagen-induced arthritis

AIM：To investigate the mechanism of tetramethylpyrazine (TMP) in treating collagen-induced arthritis (CIA) in rats. METHODS：The rat model of type II collagen-induced arthritis was established and the rats were randomly divided into normal control group, CIA group and TMP treatment group. The protein expression of matrix metalloproteinase 13 (MMP-13) in paw tissues was detected by immunohistochemical staining and Western blotting. The histopathological changes of the skin in the rat paws were observed with HE staining. The levels of vascular endothelial growth factor (VEGF), interleukin 17 (IL-17) and interleukin 23 (IL-23) in the serum of CIA rats were detected by ELISA. RESULTS：Compared with CIA group, TMP at a dose of 100 mg/kg significantly reduced the weight loss in CIA rats and decreased the protein expression of MMP-13 by 31.82%. TMP also attenuated the pathological changes of the paw subcutaneous tissues. TMP obviously decreased the levels of VEGF by 33.33%, IL-17 by 27.40% and IL-23 by 33.33% in the serum. CONCLUSION：TMP significantly inhibits the development of CIA by decreasing the protein expression of MMP-13, inhibiting the inflammatory cell infiltration and vascular proliferation, and reducing the production of VEGF, IL-17 and IL-23 in CIA rats.     

Effects of baicalin on serum levels of IL-6 and IL-4 in mouse periodontitis

AIM: To investigate the effect of baicalin on experimental periodontitis in mouse model by comparing the histological changes in periodontal tissues and serum levels of inter leukin(IL)-6/IL-4 in mice, and to analyze the role of baicalin in immune regulation and anti-inflammatory mechanisms. METHODS: Twenty-seven male Kunming mice (SPF grade, 12-week-old) were randomly divided into 3 groups. The naive mice were used in normal control group. In experimental periodontitis group, the periodontitis model was produced by ligature of braided silk around the first maxillary molar and inoculation with putative periodontopathic bacteria. Five weeks after the ligature, the mice were fed with 10% glucose, and gavaged with distilled water. In baicalin treatment+periodontitis group, the periodontitis model was induced as above, then gavaged with baicalin at the beginning of the fifth week after the ligature. The mice were sacrificed at week 4, 6 and 8. The histological changes of the periodontal tissues were observed under microscope with hematoxylin and eosin (HE) staining. The serum level of IL-6 and IL-4 in the mice were determined by ELISA. RESULTS: The periodontal tissues showed moderate inflammatory damages in experimental periodontitis group. The periodontal destruction was significantly reduced in baicalin treatment+periodontitis group. The serum level of IL-6 in experimental periodontitis group was significantly higher than that in control group and baicalin treatment+periodontitis group (P<0.01), and the serum level of IL-6 in baicalin treatment+periodontitis group was significantly lower than that in periodontitis group at week 6 and 8 (P<0.01). The serum level of IL-4 in periodontitis group was significantly lower than that in control and baicalin treatment+periodontitis group (P<0.01). The serum level of IL-4 in baicalin treatment+periodontitis group was significantly higher than that in periodontitis group at weeks 6 and 8 (P<0.01).CONCLUSION: The pathogenesis of periodontitis is closely related to the imbalance of Th1/Th2 cytokines, characterized by increased serum level of IL-6 and the decreased serum level of IL-4. Baicalin plays a significant role in treating mouse periodontitis by decreasing the serum level of IL-6 and increasing the serum level of IL-4.     

Expression of Th cytokines in peripheral blood before and after splenectomy in immune thrombocytopenia patients

AIM: To investigate the changes of Th cytokines before and after splenectomy in immune thrombocytopenia (ITP) patients. METHODS: The QuantiGene Plex method was used to measure the mRNA expression of Th1, Th2 (IL-4, IL-5, IL-6 and IL-10), Th3 (transforming growth factor β₁,TGF-β₁), and Th17 (IL-17) cytokines in peripheral blood of ITP patients before and after laparoscopic splenectomy and those in peripheral blood of healthy controls. RESULTS: The mRNA level of IL-2 was significantly decreased in ITP patients before operation compared with the healthy controls, whereas IL-17 was obviously over-expressed. No significant difference of the other cytokines between preoperative group and the normal controls was found. After splenectomy, the expression levels of both IL-2 and TGF-β₁ were significantly higher than those in preoperative group and the normal controls. IL-2 was also significantly increased after operation, but was still lower than that in the normal controls. No significant difference of other cytokines between postoperative group and healthy controls was observed. In addition, The Th1 cytokines (IL-2 and IFN-γ) were found to be positively correlated (r=0.647, P<0.01) in preoperative patients, while no correlation was found between the other cytokines. There was a positive correlation between IL-2 and IFN-γ (r=0.787, P<0.01) in postoperative patients. IL-17 also had positive correlations with IL-2 (r=0.554,P<0.01) and IFN-γ (r=0.461,P<0.05) in ITP patients after operation, respectively. CONCLUSION: There is an imbalance of Th cytokines in ITP patients. The mechanism of splenectomy for treating ITP may be associated with the balance regulation of Th cytokines.     

Levels of IL-17, IL-8 and VEGF in bronchoalveolar lavage fluid in asthma children

AIM: To investigate the mechanism of airway inflammation in children with asthma by determining the levels of IL-17, IL-8 and vascular endothelial growth factor(VEGF) in bronchoalveolar lavage fluid (BALF). METHODS: Eighty-eight children were enrolled in the study and divided into asthma group (n=52), pneumonia group (n=25) and control group (n=11). BALF were collected from all 88 cases. The levels of IL-17, IL-8, VEGF, IL-4 and IFN-γ in BALF were measured by ELISA. The cell types in BALF were determined. RESULTS: Compared with the control, the levels of IL-17 and IL-8 were significantly elevated in asthma group and pneumonia group (all P<0.05). The level of IL-8 (P<0.05) in the patients with asthma was lower than that in the pneumonia patients. No statistical difference of the IL-17 level between asthma group and pneumoniae group was observed (P>0.05). Compared with pneumonia group and control group, the level of VEGF was significantly increased in asthma group (all P<0.01), and the VEGF level among control group and pneumonia groups was almost similar (P>0.05). The levels of IL-4 and IFN-γ, and ratio of IL-4/IFN-γ among groups were not statistically different. The percentage of neutrophils in BALF was significantly higher in asthma group and pneumonia group than that in control group (all P<0.01). CONCLUSION: IL-17, IL-8 and VEGF play important roles in airway inflammation in children with asthma. Th17 cells may participate in the pathogenesis of asthma in children.     

Adipose-derived stem cells mediate immunosuppression of Th17 in multiple sclerosis

AIM: To investigate how human adipose-derived stem cells (hASCs) regulates the differentiation of Th17 cells in multiple sclerosis. METHODS: hASCs were isolated from the adipose tissues. Magnetic-activated cell sorting (MACS) kit was used to isolate CD4⁺ T cells from peripheral blood mononuclear cells (PBMCs) which were isolated by density gradient centrifugation. The percentage of CD4⁺ T cells was detected by flow cytometry. The activated CD4⁺ T cells were co-cultured with hASCs for about 4 d at different ratios of hASCs to CD4⁺ T cells (1:4 and 1:10) in a Th17 polarised condition. Another group adding anti-leukemia inhibitory factor (LIF) antibody was set up. Th17 cell proportion of the CD4⁺ T cells was determined by flow cytometry. The level of LIF in the supernatant of co-cultured system was measured by ELISA. The mRNA expression of retinoid-related orphan receptor γt (RORγt), interleukin-6 receptor (IL-6R), interleukin-23 receptor (IL-23R), LIF and leukemia inhibitory factor receptor (LIFR) was detected by real-time PCR. RESULTS: The result of flow cytometry suggested there were mainly hASCs, and the percentage of CD4⁺ T cells in the PBMCs were above 90% after MACS. The Th17 cell proportion decreased in 1:4 and 1:10 co-cultured groups in a dose-dependent manner. The mRNA expression of IL-6R, IL-23R and RORγt was downregulated and the expression of LIFR and LIF was up-regulated. When the anti-LIF was added into the co-cultured system, the ratio of Th17 cells increased and reached to the control level. The protein level of LIF obviously increased after co-cultured. After anti-LIF added, the mRNA expression of RORγt and IL-6R was up-regulated. CONCLUSION: hASCs inhibits the differentiation of Th17 cells from multiple sclerosis patients through the competitive inhibition of LIF/IL-6 by secreting LIF.     

Balance of Treg/Th17 in synovium of collagen-induced arthritis rats and impact of TNF-α blockage therapy

AIM: To investigate the balance of Treg/Th17 in synovium of collagen-induced arthritis (CIA) and the impact of tumor necrosis factor α(TNF-α) blockage therapy. METHODS: Rat CIA model was established by bovine II collagen injection. The pathological score was evaluated by HE staining and toluidine blue staining. The TNF-α level in plasma was measured by ELISA. The expression of Treg/Th17 in synovium was detected by double staining immunofluorescence. RESULTS: The plasma level of TNF-α in CIA group was significantly higher than that in control group and TNFR-Fc treatment group (P<0.01), whereas no significant difference was found between TNFR-Fc treatment group and control group (P>0.05). No significant difference between CIA group and control group in the ratio of CD4⁺Foxp3⁺Treg cells/CD4⁺ cells in synovium (23.12%±4.93% vs 24.66%±5.82%, P>0.05) was observed, whereas the ratio in TNFR-Fc treatment group was significantly increased(33.07%±5.14%). The ratio of CD4⁺RORγt⁺Th17 cells/CD4⁺ cells in CIA group was significantly higher than that in control group and TNFR-Fc treatment group (9.74%±2.23% vs 1.00%±0.59%, 5.63%±1.76%, P<0.01). CONCLUSION: Differentiation disturbance of Treg/Th17 exists in the synovium of CIA rats. TNFR-Fc may restore the balance of Treg/Th17 by inhibiting Th17 cell differentiation and inducing the production or accumulation of Treg.