Influences of protein kinase C inhibitors on the expression of IL-2 and IFN-γ by human T-lymphocytes

AIM:To investigate the influences of protein kinase C(PKC) inhibitors on the expression of interleukin-2(IL-2) and interferon-γ(IFN-γ) byin vitro activated T-lymphocytes. METHODS:Double fluorescent staining together with flow cytometry was adopted to detect intracellular cytokines and to analyze the effects of H7 and gossypol on IL-2 and IFN-γ expression levels of T-lymphocytes stimulated with phorbol ester (PDB)+ionomycin(I) in the presence of monensin.RESULTS:The expression rates of IL-2 and IFN-γ of CD3⁺ T cells stimulated with PDB+I for 4 h were 16.64±2.04 and 25.81±3.53(x±s), respectively, which were significantly higher than that of control (1.06±0.22 and 3.12±0.77)(P＜0.05). Gossypol was able to inhibit the expression of IL-2 and IFN-γ significantly, with the expression rates of 2.08±0.12 and 9.01±1.90, respectively. At the presence of 50 μmol/L H7, the rates of IL-2⁺ and IFN-γ⁺ CD3⁺ T cells were 0.43±0.06 and 2.40±0.27, respectively. The effect of H7 was stronger than that of gossypol. CONCLUSION:PKC plays an important role in the expression of IL-2 and IFN-γ of CD3⁺T cells and its inhibitors H7 and gossypol exert significant inhibitory effect on the expression of these two cytokines. It is suggested that H7 and gossypol may have modulatory effect on T-cell-dependent specific immune responses by inhibiting PKC activity.     

Changes of CD28, CD56 and CD57 expression on CD8+T cells in the peripheral blood of healthy elderly individuals

AIM:The expression of CD28, CD56 and CD57 on CD8⁺T cells in the peripheral blood of young (age range 20-35) and elderly(age range 60-75) healthy donors were compared to explore the change of the cellular immune function with aging.METHODS:Three-color fluorescent flow cytometry was performed to analyze the differences in percentage of CD8⁺CD28⁺, CD8⁺CD56⁺ and CD8⁺CD57⁺T cells in the peripheral blood between the young and elderly groups.RESULTS:CD8⁺CD28⁺T cells in the peripheral blood of the elderly group was significantly lower than those in the young group, with percentage of 34.07±5.28 and 49.84±7.43,respectively (P＜0.05). Conversely, CD8⁺CD56⁺T cells and CD8⁺CD57⁺T cells in the peripheral blood of the elderly group were significantly higher than those in the young group, and the percentage was 6.60±2.40 vs 2.10±0.35,41.82±6.01 vs 22.89±2.80, respectively(P＜0.05).CONCLUSION:The expression of CD28, CD56 and CD57 on the CD8⁺T cells in the peripheral blood are changed significantly with aging. The decrease in CD28 expression may play an important role in the immunosenescence, while the increase in CD56 and CD57 expression seems to be a compensatory adaptation for the immune dysfunction.     

The biological characteristics of cytokine-induced killer cells

AIM:To investigate the biological characteristics of cytokine-induced killer (CIK) cellsin vitro.METHODS:The non-adhere peripheral blood monoclear cells from healthy donors were induced into CIK cells in the presence of IFN-γ, IL-1β, IL-2 and anti-CD3 antibody. LAK (lymphokine activated killer) cells were prepared as a control. The cellular phenotype were detected by FCM and immunocytochemistry and the cytotoxicity was measured by LDH release assay.RESULTS:After 2 weeks of induction, the proliferation rate of CIK cells reached a peak and the proportion of CD3⁺ population was above 95%, and then the cells growth entered to plateau phase at week 3. The proportion of CD3⁺CD56⁺ NKT subset cells was 16.5% on day 15 and it had no obvious variety between 2 and 4 weeks. Correspondingly, LAK cells grew slowly and had lower proliferation rate compared with the CIK cells (P<0.01). CIK cells showed higher specific lysis rates to BeL-7402 hepatoma cells than those of LAK cells at different effector to target ratio (P<0.01). Immunocytochemical staining showed the CIK cells highly co-expressed HLA-DR and CD54 antigens. The NKT cells were slightly bigger than CD3⁺CD56^- cells and a large quantity of pseudopodia were observed on their surface.CONCLUSION:The CIK cells have higher proliferation potency and stronger cytotoxicity to lyse tumor cells than LAK cellsin vitro.Within the span of time from 14 to 21 days, the proliferation rate and the proportion of CD3⁺CD56⁺ subset of CIK cells all reach peaks. Therefore, CIK cells in this period are suitable for clinical application.     

Analysis of activation of T cells from draining lymph node and peripheral blood in allotransplantation mice

AIM:To study the activation of T cells from local lymph node and peripheral blood early after allotransplantation.METHODS:Transplant of myocardio-tissue into mouse forearm subcutaneously was used as a model to analyze the expression of CD69 by T subpopulations from draining lymph node and peripheral blood by flow cytometry.RESULTS:The expression rates of CD69 by both CD4⁺T cells and CD8⁺T cells from the draining lymph node were raised (P＜0.01) 72 h after allotransplantation, and it was higher on CD8⁺T cells than on CD4⁺T cells (P＜0.01). No significant difference in CD69 expression was found on CD4⁺T and CD8⁺T cells from peripheral blood among the groups, topical complete Freund's adjuvant (CFA) and systemic cyclosporin(CsA) enhanced and inhibited expression of CD69 by both CD4⁺T cells and CD8⁺T cells after allotransplantation, respectively (P＜0.05 or P＜0.01).CONCLUSION:To detect the expression of CD69 by T cells from draining lymph node can keep insight to the allorecognition early after transplantation.     

Effect of adoptive transfer of CD4+ T cells with miR-7 knockdown on acute liver injury in mice

AIM:To study the effect of adoptive transfer of CD4⁺ T cells with microRNA-7 (miR-7) knockdown (KD) on mouse acute liver injury model and to investigate its significance. METHODS:CD4⁺ CD62L⁺ T cells were purified from the spleen of normal wild-type (WT) mice and miR-7KD mice by magnetic bead sorting, and were stained with CFSE. These 2×10⁶ CFSE-labeling cells were injected into normal mice via tail vein, and then the mouse acute liver injury model was induced by intraperitoneal injection of 30 mg/kg concanavalin A. After 72 h, the appearance, weight and weight index of the liver were investigated. The pathological change of the liver tissues was observed by HE staining. Real-time PCR was used to examine the mRNA expression of Bax and P53. The expression levels of CD62L, interleukin-4 (IL-4) and interferon-γ (IFN-γ) in the CD4⁺ T cells were analyzed by flow cytometry. RESULTS:We found that the liver tissue became lighter, and the weight (P<0.01) and weight index (P<0.05) were changed significantly in miR-7KD mice compared with control group. Moreover, HE staining showed that the liver cell damage was increased in the liver of miR-7KD mice. Meanwhile, the expression levels of Bax and P53 were significantly increased in miR-7KD group (P<0.05). The percentage of CD62L in CD4⁺ T cells was significantly decreased (P<0.01) in miR-7KD mice, with high expression of IFN-γ (P<0.05) and low expression of IL-4 (P<0.01) in CD4⁺T cells. CONCLUSION:These findings suggest that miR-7 knockdown significantly promotes the pathology of CD4⁺ T cell-mediated acute liver injury, which provides a preliminary experimental basis for further exploration on the mechanism of acute liver injury occurrence.     

Effects of glucocorticoid on miRNA-155 expression in CD4+T cells of asthmatic mice

AIM:To investigate the effects of glucocorticoid on the regulation of microRNA-155 (miRNA-155) expression in the CD4⁺ T cells of asthmatic mice. METHODS:The ovalbumin (OVA)-induced asthma mouse model was established and the mice were treated with glucocorticoid. The effects of glucocorticoid on the pulmpnary histopathological changes, the expression of miRNA-155 in the lung tissues and CD4⁺T cells, and the levels of cytokines in the bronchoal-veolar lavage fluid (BALF) were evaluated. RESULTS:The results of RT-qPCR showed that the expressions of miRNA-155 in the lung tissues and CD4⁺T cells from the spleen of asthmatic mice were significantly increased, and the level of miRNA-155 in the CD4⁺T cells was significantly increased with the increase in the allergen exposure time (P<0.01). HE and PAS staining showed that OVA significantly increased inflammatory cell infiltration as compared with control group, and the peribronchial and perivascular inflammation and mucus secretion of proliferative goblet cells were significantly reduced after glucocorticoid treatment. Glucocorticoid treatment inhibited the increase in the proportion of CD4⁺ CD8^- cells in the spleen and decreased the accumulation of CD4⁺ T cells in the lung tissues of asthmatic mice (P<0.01). After glucocorticoid treatment, the levels of interleukin-4 (IL-4), IL-5 and IL-13 in BALF were decreased, while the level of interferon-γ was increased significantly (P<0.01). CONCLUSION:Glucocorticoid reduces the accumulation of CD4⁺ T cells and inhibits the expression of miRNA-155 in the lung tissues and spleen CD4⁺ T cells of asthmatic mice.     

Relationship between invasion of tumor-associated macrophages and phenotype and immune efficacy of tumor-infiltrating lymphocytes in advanced ovarian carcinoma

AIM:To explore the relationship between the invasion of tumor-associated macrophages(TAM) and the phenotype and immune efficacy of tumor-infiltrating lymphocytes(TIL) in advanced ovarian carcinoma. METHODS:Immunohistochemical analysis of TAM density in 175 cases of poorly-differentiated ovarian cancer tissue biopsy was performed. The cases were divided into TAM high-density(TAM^High) group and TAM low-density(TAM^Low) group according to the median of TAM density. The control group included 32 cases of benign ovarian lesions. The changes of CD8⁺ and CD25⁺ phenotypes of TIL were detected by flow cytometry analysis. TIL in the 2 groups were cultured in vitro and the conditioned-medium was collected for detecting the expression of IL-2, IL-10, TGF-β and IFN-γ by ELISA. RESULTS:The average TAM infiltration density was 62.8/high-power field(HP, ×400) in 175 cases of poorly-differentiated ovarian carcinoma, and the median was 53.3/HP. TAM^High group was 87 cases and TAM^Low group was 88 cases. A significant difference between malignant ovarian carcinoma group and control group(10.5/HP) was observed. The mean expression of CD8⁺ TIL in TAM^High group was 24%, and CD8⁺ TIL in TAM^Low group was 52%(P<0.05). The mean expression of CD25⁺ TIL in TAM^High was 48%, and CD25⁺ TIL in TAM^Low was 25%(P<0.05). The average infiltration density of CD8⁺ and CD25⁺ TIL in control group was 7%. The average infiltration density of CD8⁺ and CD25⁺ TIL in TAM^High and TAM^Low groups was significantly higher than that in control group(P<0.05). Compared with TAM^Low group, TIL destruction cytokines IL-2 and IFN-γ were significantly decreased in TAM^High group(P<0.05), while the inhibitory cytokines IL-10 and TGF-β were significantly increased(P<0.05). CONCLUSION:In high-density TAM infiltration of ovarian cancer tissues, CD25⁺ TIL type and inhibitory cytokines IL-10 and TGF-β increase, while CD8⁺ TIL type and destruction cytokines IL-2/IFN-γ decrease, suggesting that the high-density TAM has relationship with the phenotype and immune efficacy of TIL.     

Effects of magnesium on apoptosis and expression of Foxp3 in peripheral CD4+CD25+ regulatory T cells from asthma patients

AIM:To observe the apoptosis and the expression of forkhead box protein 3(Foxp3) induced by magnesium in CD4⁺CD25⁺ regulatory T cells isolated from healthy and asthmatic human peripheral blood. METHODS:Peripheral blood from healthy volunteers and asthma patients was collected. CD4⁺CD25⁺ T cells were separated by Percoll centrifugation and magnetic separation. The cells were cultured for 72 h and treated with magnesium(10 mmol/L) or control solution. The apoptotic rate and the expression of Foxp3 in the cells were analyzed by flow cytometry. RESULTS:The purity of CD4⁺CD25⁺T cells was 77.4%~92.3% in health group, and was 75.2％~93.8％in asthma group. The proportion of CD4⁺CD25⁺ T cells in CD4⁺T cells was 4.12%~7.98% in healthy adults, and 4.51%~8.68% in asthma patients. No significant difference between the 2 groups was observed. Magnesium at concentration of 10 mmol/L up-regulated the apoptotic rate of CD4⁺CD25⁺ T cells(P<0.05) and did not affect the Foxp3 expression in the cells in both health and asthma groups. CONCLUSION:Magnesium plays therapeutic effects on asthma by inducing the apoptosis of peripheral CD4⁺CD25⁺ regulatory T cells.     

Effects of Foxp3 transfection on splenocyte functions in asthma mice

AIM: To study the expression and the effects of Foxp3 on the immunologic functions by transfecting the Foxp3 eukaryotic expression plasmid into the splenocytes of the asthma mice. METHODS: The mice were sensitized and challenged by ovalbumin to make asthma model. The splenocytes were harvested and cultured. The Foxp3 expression vector pcDNA3.1(-)-Foxp3 was transfected into the splenocytes with electroporation. The splenocytes transfected with empty vector and control splenocytes (non-transfected) were also set up. The expression of Foxp3 at mRNA and protein levels was detected by RT-PCR and Western blotting, respectively. The proportion of CD4⁺CD25⁺ Treg cells/CD4⁺ cells was measured by flow cytometry. Proliferation of the splenocytes was analyzed with MTT assay. ELISA was used to determine the levels of interleukin 4 (IL-4) and interferon γ (IFN-γ) in the supernatant of the splenocytes. RESULTS: The expression of Foxp3 at mRNA and protein levels in transfection group was significantly higher than that in empty vector group and control group. The proportion of CD4⁺CD25⁺Treg cells/CD4⁺ cells in transfection group was higher than that in empty vector group and control group. The proliferation of transfected cells was markedly inhibited compared with empty vector group and control group. The levels of IL-4 and IFN-γ were significantly lower in transfection group than those in empty vector group and control group. CONCLUSION: The transfected Foxp3 gene overexpresses in the splenocytes of asthma mice. Foxp3 increases the number of CD4⁺CD25⁺ T cells and inhibits the proliferation and production of Th1/Th2 cytokines in splenocytes.     

Effect of pachyman polysaccharides on Th17/Treg balance in systemic lupus erythematosus patients

AIM: To investigate the immunomodulatory effect of pachyman polysaccharides (PPS) on T helper 17 cell (Th17)/regulatory T cell (Treg) balance in the peripheral blood of systemic lupus erythematosus (SLE) patients. METHODS: The CD4⁺ T cells were isolated from the peripheral blood samples obtained from 45 SLE patients and 35 healthy controls enrolled in our study using magnetic bead separation method. The proportions of Th17 and Treg cells were measured by flow cytometry. The CD4⁺ T cells from SLE patients and healthy controls were treated with PPS. The cytoto-xicity of PPS was evaluated by detecting cell viability with MTT assay. The contents of interleukin-17 (IL-17), IL-6, IL-10 and transforming growth factor-β (TGF-β) were measured by ELISA. The expression of retinoid-related orphan receptor γt (RORγt) and forkhead box protein P3 (Foxp3) at mRNA and protein levels was determined by RT-qPCR and Western blot, respectively. RESULTS: The Th17 cells were significantly elevated, while Treg cells were obviously decreased in the SLE patients compared with the healthy control group (P<0.05). Compare with control group, the contents of IL-17 and IL-6 were decreased, while the contents of IL-10 and TGF-β were increased (P<0.05). The expression of RORγt at mRNA and protein levels was down-regulated and the expression of Foxp3 was up-regulated (P<0.05). The ratio of Th17/Treg was decreased in 100 μg/L nontoxic PPS-treated CD4⁺ T cells isolated from the SLE patients (P<0.05). CONCLUSION: PPS treatment inhibits Th17 cells and elevates Treg cells in the CD4⁺ T cells isolated from SLE patients, which may have a therapeutic effect on SLE patients.     

TL1A promotes development of intestinal fibrosis associated with chron?ic experimental colitis by regulating IL-17 and IFN-γ

AIM To explore how tumor recrosis factor ligand-related molecule 1A (TL1A) promotes the development of intestinal fibrosis associated with chronic experimental colitis by regulating interleukin-17 (IL-17) and interferon-γ (IFN-γ). METHODS Aexperimental colitis-associated wild-type (WT) and TL1A (L-Tg) transgenic intestinal fibrosis model was established by dextran sulfate sodium (DSS) induction.The severity of colitis was evaluated by detecting the disease activity index (DAI). HE staining was used to observe the histopathological changes and pathological score of the colitis.Myeloperoxidase (MPO) was measured in each group. The collagen deposition was detected by Masson’s trichrome staining and Sirius red staining. The lamina propria, spleen and mesenteric lymph nodes(MLN) mononuclear cells were isolated and counted, and the levels of IL-17 and IFN-γ weremeasured by ELISA, andthe percentages of CD4⁺IFN-γ⁺T cells and CD4⁺IL-17⁺T cells were analyzed by flow cytometry. RESULTS After drinking DSS water,the body weight of the mice in DSS/Tg group was decreased significantly as compared with WT group(P<0.05). The DAI score, histology score and MPO activity were significantly increased(P<0.05). Thelevels of IL-17 and IFN-γ, LPMC, spleen and MLN were significantly increased. The percentages of CD4⁺IFN-γ⁺T cells and CD4⁺IL-17⁺T cells were significantlyincreased.The thickness and collagen deposition of the colon were increased inTg group. CONCLUSION TL1A promotes the development of intestinal fibrosis associated with chronic experimental colitis by regulating IL-17 and IFN-γ.     

Effects of psychological stress on in vitro expression of activated surface molecules on T cells of peripheral blood from healthy persons

AIM: To study cellular and molecular mechanism involved in increasing susceptibility of infection in psychological stress persons. METHODS: Comparative studies were performed with double staining and flow cytometry analysis on immunophenotyping and in vitro expression of early activating surface molecule CD69 in response to mitogens on T cells from peripheral blood of 20 healthy college student volunteers before and after psychological stress. A series of term final examinations was defined as psychological stress. RESULTS: Immunophenotyping analysis showed no statistically significant difference in the percentage of CD2, CD3, CD4, CD8, CD19, CD20, CD16 and CD56 positive lymphocyte populations before and after psychological stress. There was a statistically significant decrease in the in vitro expression of CD69 in response to polyclonal stimulators on the T cells from persons after psychological stress than those before psychological stress. The percentage of CD69 expression (CD69⁺CD3⁺/CD3⁺%) in response to PHA and PDB in the whole blood culture for 72 hours decreased respectively from 28.1±4.1 and 80.7±6.8 on the T cells obtained before psychological stress to 17.6±3.8 and 65.8±7.9 on those obtained after psychological stress, while there was no statistically significant difference between the CD69 expression rates without stimulators on the T cells obtained before and after psychological stress. CONCLUSIONS: The effects of psychological stress to immune system is not on the level of changing proportions of the sub-populations within peripheral blood lymphocytes. Psychological stress can decrease the activating response of T cells in healthy persons, which may be responsible for the increase of susceptibility to infection in the psychological stress persons.     

Effects of recombinant viral chemokine vMIP-II on cellular immunity stimulated by LPS

AIM: To investigate the produce of intracellular cytokine following short-term in vitro stimulation with vMIP and LPS, and discuss the effect of vMIP to cellular immunity. METHODS: The methods of Cross-linking of radioactivity, ELISA and four-colors flow cytometer were used to test the level of the secretion of chemokine IL-12 and intracellular cytokine IFN-γ and IL-4. RESULTS: After treated the PBMCs with vMIP-II, the levels of secretion of IL-12, IFN-γ and IL-4 were reduced in the present of LPS by competitively combining chemokine receptor; vMIP promoted CD4⁺T cell to secrete IL-12, IFN-γ and IL-4. CONCLUSION: vMIP-II can protect systemic response of immunity and reduce extremely inflammation by down-regulating proinflammation.     

Calreticulin expression is necessary for protective immune effect of T-cell vaccine in EAE mice

AIM:To study the role of cell membrane ectopic calreticulin (CALR) expression on the protective immunie effect of T-cell vaccine (TCV) on experimental autoimmune encephalomyelitis (EAE). METHODS:EAE model was established by myelin oligodendrocyte glycoprotein 35-55 (MOG_35-55) immunization in C57BL/6 mice, and the mice were immunized with MOG_35-55-specific CALR⁺ and CALR^- T-lymphocytes. Symptomatic scores were compared at the maximum of the disease. On the 15th day after immunization, the proportion of CD4⁺ CD25⁺ Foxp3⁺ regulatory T cells (Treg) in the spleen, and the expression of interferon-γ (IFN-γ), interleukin-4 (IL-4), IL-10 and IL-17A in the serum were measured. RESULTS:Increased expression of CALR in activated T cells after γ-irradiation was observed. Blockade of CALR on the vaccinating T-cell surface reduced the protective effect of TCV. Furthermore, blockade of CALR reduced the number of Treg in the spleen and up-regulated pro-inflammatory cytokines. CONCLUSION:CALR expression in the T cells is necessary for the protective immunity induced by TCV in EAE mice.     

Study on polarized Th1/Th2 cell in vitro from adult human peripheral blood

AIM: To investigate the details of CD4⁺ T cell polarized to Th1/Th2 in vitro. METHODS: After isolated the PBMCs and blood-plasma from adult human peripheral blood by Ficoll-Hypaque centrifugation, the PBMC culture procedure with or without the self-blood -plasma was applied to polarize T cells in vitro, these cells were polarized by PHA(20 mg/L),non-PHA respectively. The polarized rates of Th cell after 24 h,48 h,72 h were estimated respectively by flow cytometry following two-color immunofluorescent staining. RESULTS: CD4⁺T cell would polarize to Th1/Th2 two subsets after self-cytokines and PHA activation in vitro. The polarized rates of T cell after cultured for 24 h,48 h and 72 h were (13.28%±1.59%)/(12.70%±1.65%),(17.19%±1.03%)/(17.50%±1.30%),(19.49%±2.87%)/(18.58%±1.49%) respectively, but the polarized rates of T cell were very low if without self-blood-plasma. The difference between them was significant. The ratios of Th1/Th2 cells were about 1. CONCLUSION: CD4⁺T cell from adult human peripheral blood would polarize to Th1/Th2 two subsets in the presence of self-blood-plasma and PHA(20 mg/L) in vitro, and the cell number of Th1 and Th2 would be in balance.     

Inhibitory effects of gossypol on the activation of human T-lymphocytes stimulated with polyclonal activators

AIM: Peripheral blood mononuclear cells (PBMC) were cultured in vitro to study the effect of gossypol, a polyphenolic antifertility agent, on the activation of normal human T cells. METHODS: Double fluorescent staining together with flow cytometry was adopted to analyze the influence of gossypol on expression of the early activation antigen CD69 on T-lymphocytes under stimulation of mitogen or phorbol ester. RESULTS:Analysis of T cell activation in vitro revealed that preincubation of PBMC with 100 μmol/L gossypol could completely inhibit the expression of early activation marker CD69 on CD3⁺ T cells in response to 10mg/L PHA, and block T cell activation by 10^-7 mol/L PDB as well. The suppression of CD69 expression was dose-dependent and IC₅₀ of gossypol on PDB and PHA were (35.7±2.9) μmol/L and (32.8±1.5) μmol/L(x ±s), respectively. Besides, gossypol had similar inhibitory effect on CD69 expression of CD3^- lymphocytes. However, it did not have any significant effect on T cell surface molecule CD3 down-regulation. CONCLUSION: Gossypol could inhibit T cell activation in vitro in response to polyclonal activators, both PHA and PDB, suggesting that its action site may be at PKC or its downstream and that gossypol possessed potential immuno-regulatory effect.     

Immunological mechanism of long-term stimulation by LPS in macrophages

AIM: To investigate the molecular mechanism and the immunosuppressive phenotype of macrophages under long-term exposure to lipopolysaccharide (LPS). METHODS: We used Ficoll-Hypaque density gradient centri-fugation combined with MicroBeads Separation Kits to separate peripheral blood mononuclear cells from human blood, and then induced the monocytes into macrophages. We observed the morphology of the macrophages by treating the cells with LPS for 48 h, in comparison with a negative control and IFN-γ treatment. ELISA was used to detect the levels of cytokines, such as IL-10, IL-12, IL-6 and TNF-α, and flow cytometry was used to detect the expression of the surface molecules (HLA-DR, CD14, CCR7, HLA-ABC and CD40). To observe the effect of macrophage on T cell proliferation, co-culture experiment was carried out for 6 d. Real-time PCR was used to validate the expression levels of molecules related to MyD88-independent pathway in Toll-like receptor 4 (TLR4) signal pathway. RESULTS: The antigen-presenting ability of the macrophages was reduced and the IL-10 expression level was increased after the cells were treated with LPS for 48 h. We observed a poor proliferative capacity of CD8⁺ T cells after co-culturing of LPS-induced macrophages with CD3⁺ T cells for 6 d. The results of real-time PCR indicated that TRIF, IRF3 and CIITA were down-regulated in LPS-induced macrophages.CONCLUSION: We successfully established a macrophage model in vitro and observed that LPS-induced macrophages into an immunosuppressive phenotype with poor CD8⁺ T cell proliferative capacity, in which MyD88-independent TLR4 signaling pathway was impaired.     

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.     

Anti-Sonic hedgehog blocking antibody enhances killing effect of PBMCs on cervical carcinoma HeLa cells

AIM: To investigate the effect of anti-Sonic hedgehog(Shh) blocking antibody on the killing effect of peripheral blood mononuclear cells(PBMCs) on cervical carcinoma HeLa cells. METHODS: The expression levels of Shh and Shh signaling molecules in HeLa cells were detected by immunocytochemistry and RT-PCR. PBMCs from health peoples were isolated by the method of Ficoll density gradient centrifugation, and then co-cultured with HeLa cells in vitro. The expression of CD3, CD69 and CD71 was assayed by flew cytometry. The concentrations of IFN-γ, IL-10 and IL-4 in culture supernatants were detected by ELISA. The killing effect of PBMCs on HeLa cells was observed under microscope. RESULTS: Shh and Shh signaling molecules were expressed in HeLa cells. The level of Shh expression didn't change significantly in the 6th passage of HeLa cells. CD3⁺ cells were increased in the co-culture system. The expression of CD69 and CD 71, and the secretion of IFN-γ were increased, while the secretion of IL-10 was decreased in the co-culture system treated with anti-Shh blocking antibody. Anti-Shh blocking antibody has no effect on the secretion of IL-4. The killing effect of PBMCs on HeLa cells was strengthened by anti-Shh blocking antibody. CONCLUSION: Anti-Shh blocking antibody promotes the activation of PBMCs and enhances the killing effect of PBMCs on cervical carcinoma HeLa cells.     

Effect of microRNA-7 knockdown on ConA-induced acute liver injury in mice

AIM: To study the effect of microRNA-7 (miR-7) knockdown (KD) on concanavalin A (ConA)-induced acute liver injury (ALI) in mice.METHODS: Wild type (WT) mice and miR-7KD mice were received ConA (30 mg/kg) to induced acute liver injury model by intraperitoneal injection, and the morphological changes, liver weight and weight index were measured 48 h later. The pathological changes of the liver tissues were observed by HE staining. The levels of serum alanine aminotransferase (ALT), IL-4 and IFN-γ were detected by ELISA. The proportional changes of CD4⁺ T cells and the relative levels of IL-4 and IFN-γ were analyzed by flow cytometry.RESULTS: The color of the liver tissue became lighter, and the weight and weight index were changed significantly in miR-7KD mice compared with control group (P<0.05). HE staining showed that the inflammatory cell infiltration was increased in the liver of miR-7KD mice. Moreover, the level of serum ALT was significantly increased (P<0.05). The serum level of IFN-γ elevated significantly (P<0.01), while the IL-4 levels decreased significantly (P<0.01) in the serum of miR-7KD mice. Furthermore, the proportion of CD4⁺ T cells and relative IFN-γ cells increased obviously (P<0.01).CONCLUSION: miR-7 knockdown promotes the pathogenesis of the ConA-induced acute liver injury in mice.