T cell receptor rearrangement excision circles ( TRECs) and CD31+ regulatory T cells for assessing recent thymic output in patients with chronic hepatitis B / 中华微生物学和免疫学杂志

Objective To evaluate the clinical value of combined detection of T cell receptor rear-rangement excision circles ( TRECs) and CD31+ regulatory T ( Treg) cells for accessing the recent thymic output in patients with chronic hepatitis B. Methods Four groups involving 135 subjects were set up in this study as follows: mild chronic hepatitis B ( Mild CHB, n=35 ) , moderate chronic hepatitis B ( Moderate CHB, n=35 ) , severe chronic hepatitis B ( Severe CHB, n=35 ) and healthy control ( HCs, n=30 ) groups. CD4+CD25+Treg cells in these subjects were sorted out using magnetic cell separation. The ratio of peripheral CD31+Treg cells to Treg cells in each group was analyzed by flow cytometry. Real-time PCR was performed to detect TRECs in CD4+CD25+Treg cells. The percentages of CD3+, CD4+ and CD8+T cell sub-sets were also measured. Results The ratios of CD31+Treg/Treg cells and the numbers of TRECs in pe-ripheral blood of the Moderate CHB and Severe CHB groups were significantly lower than those of the Mild CHB and HCs groups (P<0. 05), while no statistical difference was found between the mild CHB and HC groups (P>0. 05). No significant difference in the percentages of CD3+, CD4+ or CD8+ T cell subsets was observed between the four groups (P>0. 05). CD31+ Treg/Treg cell ratio had a positive correlation with the number of TRECs (r=0. 551, P=0. 014). Conclusions Both CD31+Treg/Treg cell ratio and the number of TRECs were reduced in the peripheral blood of patients with moderate or severe CHB. CD31+Treg/Treg cell ratio and the number of TRECs were positively correlated and could be used as new indices to evaluate recent thymus output.

[Schistosoma japonicum heat shock protein 60 enhances regulatory T cell immunosuppressive function by promoting the expressions of IL-10 and TGF-ß].

OBJECTIVE: To explore the possible mechanisms by which Schistosoma japonicum heat shock protein 60 (SjH-SP60) enhances CD4+CD25+ regulatory T cell (Treg) immunosuppressive function. METHODS: An in vitro method was used to investigate the effect of SjHSP60 on Treg immunosuppressive activity. Co-cultures in transwells and in vitro suppression assay were performed to investigate how SjHSP60 enhanced the immunosuppressive function of Tregs. Intracellular cytokine staining combined with flow cytometry was used to detect Treg-expressing IL-10 and TGF-ß, and flow cytometry was also used to analyze the expressions of Foxp3 and CTLA-4 in Tregs. RESULTS: SjHSP60 enhanced the immunosuppressive function of Tregs. Soluble cytokines IL-10 and TGF-ß mediated inhibitory activity of SjHSP60-triggered Tregs. SjHSP60 induced significant increases in both IL-10 and TGF-ß expressions of Tregs. Further investigation showed significant increased Foxp3 and CTLA-4 in SjHSP60-trggered Tregs. CONCLUSIONS: SjHSP60 enhances Treg immunosuppressive function by promoting the expressions of IL-10 and TGF-ß, possibly due to SjHSP60-mediated induction of Foxp3 and CTLA-4 in Tregs.

Schistosoma japonicum heat shock protein 60 enhances regulatory T cell im-munosuppressive function by promoting the expressions of IL-10 and TGF-β / 中国血吸虫病防治杂志

Objective To explore the possible mechanisms by which Schistosoma japonicum heat shock protein 60(SjH-SP60)enhances CD4+CD25+regulatory T cell(Treg)immunosuppressive function.Methods An in vitro method was used to investigate the effect of SjHSP60 on Treg immunosuppressive activity.Co-cultures in transwells and in vitro suppression assay were performed to investigate how SjHSP60 enhanced the immunosuppressive function of Tregs.Intracellular cytokine staining combined with flow cytometry was used to detect Treg-expressing IL-10 and TGF-β,and flow cytometry was also used to analyze the expressions of Foxp3 and CTLA-4 in Tregs.Results SjHSP60 enhanced the immunosuppressive function of Tregs.Soluble cytokines IL-10 and TGF-β mediated inhibitory activity of SjHSP60-triggered Tregs.SjHSP60 induced significant increases in both IL-10 and TGF-β expressions of Tregs.Further investigation showed significant increased Foxp3 and CTLA-4 in SjHSP60-trggered Tregs.Conclusion SjHSP60 enhances Treg immunosuppressive function by promoting the expressions of IL-10 and TGF-β,possibly due to SjHSP60-mediated induction of Foxp3 and CTLA-4 in Tregs.

Tumor-derived CD4+CD25+regulatory T cells inhibit dendritic cells function by CTLA-4.

PURPOSE: CD4+CD25+regulatoryT cells (Tregs) play an important role in anti-tumor immune responses. Poor prognosis and declining survival rates have intimate connection with high Treg expression in cancer patients. Cytotoxic T Lymphocyte-associated protein (CTLA-4) is one of the most prominent molecules on Treg. In our previous research, we have demonstrated that HCC-derived Tregs can interfere with Dendritic cells (DCs) function and down-modulate CD80/CD86 on DCs in vitro in a cell-contact dependent way. However the mechanism of how HCC-derived Treg affect DC phenotype are not very clear. Therefore, we investigated the function of CTLA-4 in anti-tumor immune responses. MATERIALS AND METHODS: We established BABL/C mouse with hepatocellular carcinoma model, and tumor-derived Tregs were purified by magnetic cell sorting using mouse CD4+CD25+regulatoryT cell isolation kit. Splenic DCs were enriched using CD11c-conjugated microbeads. Then splenic DCs co-cultured with tumor-derived Tregs and antibody-blocking experiments was performed. RESULTS: In our research, we found the down-modulation of CD80/CD86 on DCs was inhibited by blocking CTLA-4. HCC-derived Tregs down-modulated CD80/CD86 on DCs in a CTLA-4-dependent way. Blockade of CTLA-4 can lead to increase DC-mediated immunity. CONCLUSION: CTLA-4 play a vital role in Treg-mediated immnue inhibition and this discovery can open up new ideas for the development of therapeutic strategies.

The correlation of serum SOD and CD4+CD25+regulatory T cell in the mechanism of severe sepsis / 实用医学杂志

Objective To evaluate the condition of oxidative stress and immunosuppression in early stage of severe sepsis,and investigate the correlation between them. Methods A prospective random control study in-cluded patients group(n=51)and control group(n=31). The concentration of serum superoxide dismutase was measured by enzyme linked immunosorbent assay(ELISA),CD4+CD25+Treg% was measured by flow cytometry , respectively. The difference between two groups was compared and the correlation between parameters in patients group was evaluated. Results The concentration of serum SOD was lower than control group (P < 0.01). CD4+CD25+Treg% significantly high,compared to the control group(P < 0.01). There was no strong correlation be-tween parameters in patients group. Conclusion Oxidative stress and immunosuppression are exist in the early stage of severe sepsis.

Immunoregulation study of UCMSCs on UCB CD4+T lymphocytes in vitro / 中国免疫学杂志

Objective:Immunoregulation study of umbilical mesenchymal stem cell (UCMSCs) on allogeneic umbilical cord blood(UCB) CD4+T lymphocytes,which proliferation,apoptosis and the differentiation to CD4+CD25+ regulatory T cell (Treg) in vitro. Methods:Establishing on direct contact or transwell co-culture system,adopt in different proportion of UCMCs with phytohaemag-glutinin (PHA)-activated UCB CD4+T lymphocytes were co-cultured. The proliferation of lymphocyte,percent of CD4+CD25+/CD4+and Foxp3 expression, regulatory T cell marker gene were measured. Apoptosis of CD4+T lymphocytes were observed in the direct contact or transwell coculture system of UCMSCs with desamethason( DXM)-stimulated UCB CD4+T lymphocytes. Results: The UCB CD4+T lymphocytes cocultured with UCMSCs with PHA-activating for 3 days,compared with the UCMSCs free control group,the amount of cells was reduced noticeably(P<0. 05) and the percent of CD4+CD25+in CD4+T lymphocytes and Foxp3 expression significantly in-creased(P<0. 01) in a dose dependent way(P<0. 05). The UCB CD4+T lymphocytes cocultured with UCMSCs with DXM-inducing for 7 days,the apoptosis rate was significantly lower than that of the control group without UCMSCs (P<0. 01). These effects were partially attenuated in transwell coculture but could not be eliminated. Conclusion: UCMSCs are negative effect on UCB CD4+T lymphocytes-mediated immunity effects,and mainly manifested in the regulation on cell proliferate ability and differentiation rather than promoting apoptosis.

CD4+CD25+ regulatory T cells in tumor immunity.

Regulatory T cells (Tregs) are essential for maintaining peripheral tolerance, preventing autoimmune diseases and limiting chronic inflammatory diseases. Depletion of Tregs results in the onset of a variety of autoimmune diseases. Tregs are defined based on expression of CD4, CD25, and the transcription factor, FoxP3. It is now clear that three inhibitory cytokines, IL-10, IL-35 and TGF-ß, are key mediators of Tregs function. Tregs have been shown to be important contributors to the development of immune tolerance toward tumors and play a critical role in the induction of tolerance to tumor associated antigens and suppression of anti-tumor immunity. Increasing researches support the existence of elevated numbers of regulatory T cells in cancer patients. Poor prognosis and decreased survival rates are closely correlated with higher Treg cell frequencies. Depletion of Tregs or blockade of their immune inhibitory role can enhance anti-tumor effects. Recent evidence suggests that Tregs may be responsible for the failure of host anti-tumor immunity by suppressing cytotoxic T-cells. In this review, we discuss cellular and molecular mechanisms in the differentiation and function of Tregs in tumor immunity.

Combinative application CD4+ CD25+ regulatory T cells test and irregular antibody screening in the diagnosis of invalid clinical transfusion / 中国综合临床

Objective To investigate whether the T cells (CD4+ CD25+) levels and the irregular antibodies screening cloud improve the diagnosis of invalid red blood cells transfusion.Methods Thirty-one patients with red blood cell invalid transfusion in the People's Hospital of Yubei District of Chongqing were selected.Flow cytometry was used to detect the changes of CD4+CD25+ regulatory T cells.Standard cells Ⅰ,Ⅱ,Ⅲ were used to screen on irregular antibodies in red blood cells (RBC).Results The rate of invalid RBC transfusion was 7.52％ (31/412) in Yubei District.The incidence rate of medical diseases was 77.42％ (24/31),much higher than surgical disease (22.58％ (7/31,P =0.002),and the major departments were oncology department,hematological department and infectious department.The CD4+ CD25+ regulatory T cells were decrease from (22.18±1.58) ％ to (16.57±1.77) ％(P=0.023).Conclusion Combin CD4+CD25+ regulatory T cells test and irregular antibody screening can help prevent and reduce the invalid transfusionof red blood cells.

Effects of estrogen on CD4(+) CD25(+) regulatory T cell in peripheral blood during pregnancy.

OBJECTIVE: To investigate the effects of estrogen (E2) level on regulatory T cells (Treg) in peripheral blood during pregnancy. METHODS: A total of 30 healthy non-pregnant women were selected as control group, 90 pregnant women of early, middle and late pregnancy and 30 postpartum women at 1 month after parturition were selected as experimental groups including early pregnancy group, middle pregnancy group and late pregnancy group; the proportions of CD4(+)CD25(+) Treg and CD4(+)CD25(+)CD127(-) Treg among CD4(+)T cells were detected by flow cytometry; the serum estrogen content in peripheral blood was detected by electrochemical immune luminescence method. RESULTS: E2 level was coincident with the change of Tregs number during pregnancy. The estrogen content in peripheral blood increased gradually from early pregnancy to late pregnancy, then decreased significantly after parturition, and the level at 1 month after parturition down to the level in non- pregnancy group (P>0.05); the level of E2 in pregnancy groups were significantly higher than those in non- pregnancy group (P<0.01); and there were significant differences among early pregnancy group, middle pregnancy group and late pregnancy group (P<0.05). The proportions of CD4(+) CD25(+) Treg and CD4(+) CD25(+) CD127(-) Treg in pregnancy groups were significantly higher than those in non- pregnancy group (P<0.05), but decreased significantly after parturition, and there was no significant difference between non- pregnancy group and postpartum women group (P>0.05); the proportions in middle and late pregnancy groups were significantly higher than those in early pregnancy group (P<0.05), but decreased slightly in late pregnancy group, there was no significant difference between late pregnancy group and middle pregnancy group (P>0.05). There was correlation between Tregs number with estrogen level during pregnancy. The proportion of CD4(+) CD25(+) Treg and CD4(+) CD25(+) CD127(-) Treg were positively correlated with estrogen level. CONCLUSIONS: High proportion of CD4(+) CD25(+) Treg and CD4(+)CD25(+)CD127(-) Treg is closely related to the high level of E2 during pregnancy. It suggested that high level of estrogen may induce an increase of CD4(+) CD25(+) Treg in peripheral blood, and then influence the immune function of pregnant women. The results of this experiment might play an important role of estrogen in immune-modulation during pregnancy.

Effects of estrogen on CD4(+) CD25(+) regulatory T cell in peripheral blood during pregnancy

OBJECTIVE@#To investigate the effects of estrogen (E2) level on regulatory T cells (Treg) in peripheral blood during pregnancy.@*METHODS@#A total of 30 healthy non-pregnant women were selected as control group, 90 pregnant women of early, middle and late pregnancy and 30 postpartum women at 1 month after parturition were selected as experimental groups including early pregnancy group, middle pregnancy group and late pregnancy group; the proportions of CD4(+)CD25(+) Treg and CD4(+)CD25(+)CD127(-) Treg among CD4(+)T cells were detected by flow cytometry; the serum estrogen content in peripheral blood was detected by electrochemical immune luminescence method.@*RESULTS@#E2 level was coincident with the change of Tregs number during pregnancy. The estrogen content in peripheral blood increased gradually from early pregnancy to late pregnancy, then decreased significantly after parturition, and the level at 1 month after parturition down to the level in non- pregnancy group (P>0.05); the level of E2 in pregnancy groups were significantly higher than those in non- pregnancy group (P0.05); the proportions in middle and late pregnancy groups were significantly higher than those in early pregnancy group (P0.05). There was correlation between Tregs number with estrogen level during pregnancy. The proportion of CD4(+) CD25(+) Treg and CD4(+) CD25(+) CD127(-) Treg were positively correlated with estrogen level.@*CONCLUSIONS@#High proportion of CD4(+) CD25(+) Treg and CD4(+)CD25(+)CD127(-) Treg is closely related to the high level of E2 during pregnancy. It suggested that high level of estrogen may induce an increase of CD4(+) CD25(+) Treg in peripheral blood, and then influence the immune function of pregnant women. The results of this experiment might play an important role of estrogen in immune-modulation during pregnancy.

Th17 cell and CD4 + CD25 + Treg in iathogenesis of asthma / 国际儿科学杂志

Many studies have suggested that pathogenesis of asthma could no longer be interpreted merely by “Th1/Th2 balance” theory.CD4 + CD25 + Treg and Th17 cells,as well as their cytokines such as IL-10,transforming growth factor-β,and IL-17,account for asthma.CD4 + CD25 + Treg and Th17 are functionally antagonistic to each other,and also go with each other during their differentiation.Therefore,immunity-unbalance of CD4 + CD25 + Treg and Th17 is one of the most important factors that triggers asthma.Glucocorticoid has been shown to down regulate IL-17 expression by retinoic acid receptors γt signaling pathway,and regulate differentiation and function of CD4 + CD25 + Treg by inducing expression of transcription factor Foxp3,all of these are immuno-mechanisms of glucocorticoid in asthma treatment.

Progress of CD4 + CD25 + regulatory T cells in pathogenesis of idiopathic thrombocytopenic purpura / 国际儿科学杂志

CD4 + CD25 + regulatory T cells(Treg) are thought to be a subgroup of mature CD4 + T cells.Forkhead winged helix transcription factor-3 (Foxp3)is specifically expressed on them and plays a key role in their development and function. CD4 + CD25 + Treg cells can maintain the stabilization of internal environment by two principal pathways to suppress the immunological function: the direct suppression of the target cells by cell-contact and the secretion of suppressor cytokines.At present,it has been considered that decreased number and dysfunction of CD4+ CD25+ Treg cells are closely related to pathogenesis of autoimmune disease. Recent findings show that CD4+ CD25+ Treg cells play an important role in pathogenesis of idiopathic thrombocytopenic purpura.

Function and interaction of dendritic cells and CD4+CD25+regulatory T cells in immune tolerance / 国际外科学杂志

Induction of immune tolerance is characterized by high efficiency,low toxicity and economic advantages,and immune tolerance has very important significance in organ transplantation.In the establishment of immune tolerance,dendritic cells (DCs) play the key roles such as clonal deletion or clonal anerge,expressing t-cell inhibiting factors,activating helper T cells electively and inducing regulatory T cells,especially CD4 + CD25 + regulatory T cells,etc.Similarly,CD4 + CD25 + regulatory T cells whose primary target point is dendritic cell also have various functions such as affecting dendritic cells'maturing,restraining dendritic cells'antigen presentation to T cells,inhibiting the activation of T cells in non-specific ways and inducing immune tolerance.Current research shows,dendritic cells and CD4 + CD25 + regulatory T cells regard each other as target point and work synergetically.Here we mainly discuss the function and interaction of dendritic cells and CD4 + CD25 + regulatory T cells in the immune tolerance.

Establishment of experimental allergic encephalomyelitis in C57BL/6 mice and testing of expressions of Foxp3 and quantifies of CD4~+ CD25~+ regulatory T cells / 中华微生物学和免疫学杂志

Objective To induce experimental allergic encephalomyelitis (EAE) in female C57BL/6 mice with the extracellular domain of myelin oligedendroglia glycoprotein(MOG~(Igd)). Percentages of CD4~+ CD25~+ T cell (Tr) were tested , and also normalized expressions of Foxp3. Methods Molecular cloning technology was used to produce MOG~(Igd) fusion protein. The MOG~(Igd)-TrxA fusion protein and TrxA protein were purified by metal chelate affinity chromatography (MCAC). Mice were injected s. c. in the flank with 300 μg MOG~(Igd) in complete Frcund's adjuvant (CFA) supplemented with 4 μg/μl Mycobacterium tuberculosis. H37Rv. Mice received 0.4 ml emulsion of spinal cord homogenate of guinea pigs (GPSCH) in positive control group, and the same volume emulsiom of TrxA in negative control group, while mice served as normal control received only saline/adjuvant. Mice were monitored two times a day for continuously 30 days by double bind. Clinical scores and histopathology were evaluated. Then, mice were sacrificed. The spinal cord and brain were removed and fixed in buffered formalin. Horizontal sections taken from the central nervous system(CNS) were stained with haematoxylin and eosin (HE), and Kluver-Barrera staining. Also, immunohistochemistry was performed. Percentages of CD4~+ CD25~+ T cells were tested through flow cytometric analysis, and real-time PCR was performed to test normalized expressions of Foxp3 mRNA. Then, correlations between the two were performanced. Results Mice in both MOG group and GPSCH group shew chronic non-remitting course. The onset of disease, time when the most severe clinical symptoms happened and the clinical score between the two groups shew no significant differnces (P>0.05). However, neither in TrxA treated group nor in normal control group did animals exhibit clinical signs of EAE. Histologic sections of the brain and spinal cord taken from affected animals shew perivascular infiltration of mononuclear cells, gliosis, and multifocal demyelination. Lesions scattered throughout the CNS including brainstem, spinal cord, cerebellum, and penventricular white matter. There were significant differences between MOG group and TrxA group in the level of lesion-ceutric AQP-4 expression showing up by immunohistochemistry (P<0.05). Percentages of CD4~+ CD25~+ T cells in MOG group and GPSCH group were (4.71±1.61) % and (1.44±0.65) %, respectively, both of which were significantly lower than those in the normal control group or TrxA treated group (P<0.01). And the difference between MOG group and GPSCH group also reached statistics meaning (P<0.01). Normalized expression of Foxp3 mRNA in MOG group was 2.26± 1.97, and was not significantly higher than the 1.44±1.20 level in GPSCH group (P>0.05). However, they beth were statistically lower than that in the negative control group, namely 8.58±3.34 (P<0.01). Percentages of CD4~+ CD25~+ T cells was statistically correlated with expressions of Foxp3 mRNA (P< 0.05). Conclusion EAE induced in C57BL/6 mice with MOG~(Igd) is reproduceable. It shares the similar clinial signs and pathologic features with human multiple sclerosis(MS). Thus, we find a good way to further study the immune mechanisms of MS and also to search for the effective treatments.

Changes of CD4~+ CD25~+ Regulatory T Cells in Peripheral Blood and Their Relation with Their Body Mass Index of Children with Acute Attack Asthma / 中山大学学报(医学科学版)

[Objective] To investigate the changes of CD4~+ CD25~+ regulatory T cells (Tr) in peripheral blood and their relation with their body mass index (BMI) of children with acute attack asthma. [Methods] Peripheral blood was obtained from 70 children with acute attack asthma, 30 remission children, and 50 normal control children. Then 70 children with acute attack asthma, were divided by normal weight group (40 cases) and overweight group (30 cases). The levels of CD4~+CD25~+Tr of the patients were tested by flow cytometry (FCM), and their BMI were calculated. [ Results] The levels of CD4~+ CD25~+ Tr [(6.17± 1.72)%] in acute attack group were lower than that in remission group [(7.56±1.48)%] or that in the control group [(7.13± 1.48)%] (P<0.05), but no difference between that in the remission and that in the control (P>0.05). The CD4~+CD25~+Tr of asthmatic children with normal weight [(6.34±1.71)%] was higher than that of asthmatic children with overweight [(4.74±1.20)%] (P<0.05). There was a remarkably negative correlation between the level of CD4~+ CD25~+ Tr of asthmatic children [(6.17±1.72)%] and the BMI (16.00±2.14) (r_p=-0.814, P<0.05). [Conclusion] The levels of CD4~+ CD25~+Tr are remarkable decrease in attack asthmatic children, and more decrease in overweight patients. There is remarkably negative correlation between the levels of CD4~+CD25~+ Tr in peripheral blood of attack asthmatic children and their BMI.

Cyclosporin A-treated Dendritic Cells may affect the outcome of organ transplantation by decreasing CD4+CD25+ regulatory T cell proliferation

One of the mechanisms for generation of tolerance involves immature dendritic cells (DCs) and a subpopulation of regulatory CD4+ CD25+ T lymphocytes (T REG). The purpose of this work was to analyze how Cyclosporine A (CsA), a widely used immunosuppressive drug, may affect T REG proliferation. Purified and activated murine DCs obtained from bone marrow precursors differentiated with rGMCSF were co-cultured with purified CFSE-labeled T REG from OTII mice, and their phenotype and proliferation analyzed by flow cytometry. Our data indicate that DCs differentiated in the presence of CsA show an altered phenotype, with a lower expression of MHC-II and a lower activating capacity. Additionally, these CsA-treated DCs show decreased production of IL-2 and IL-12 and increased IL-10 secretion when stimulated with LPS, indicating an effect on the polarization of the immune response. Interestingly, CsA-treated DCs show an anti-tolerogenic effect since they reduce the proliferation of T REG cells from 72 to 47 percent. Further inhibition to a 24 percent of T REG proliferation was obtained as a direct effect of CsA on T REG. In conclusion, the anti-tolerogenic effect of CsA should be considered in the planning of immunosuppression in the context of clinical transplantation.

The effects and mechanisms of Forsythia suspense on the expression of Foxp3 on splenocytes and level of Treg in peripheral blood in severely burnt rats / 细胞与分子免疫学杂志

AIM: To explore the immunity modulation function of aqueous of Forsythia suspense (AFS) and its possible mechanisms. METHODS: Rats of burned model group were burned with vapor under 3mpa pressure and 108℃ temperature for 8 seconds to achieve deep partialthickness bum, to make a thirty percent total body surface area (TBSA)bum. The experiment were divided into five groups: Control group: without any treatment; 8 PBH group: 8 h after burn; the rats of AFS1 guoup, AFS2 group and AFS3 group of them were given AFS 5 g/kg, 2.5 g/kg, 1.25 g/kg once a day by Po. pathway for seven days before burns, respectively. Rats were sacrificed before and 8h after burn, The percentage of Treg cells in CD4~+ T cells was detected by flow cytometry(FCM) ; the expression of Foxp3 mRNA on splenocytes were measured by RT-PCR, and the protein of Foxp3 activity was evaluated by immunohistochemistry staining. RESULTS: Compared with Control group, the expression of Foxp3mRNA and protein on the splenocytes were upregulated markedly(P <0.01), and the percentage of Treg were significantly increased (P < 0.01) in the 8PBH group. AFS1, AFS2 and AFS3 significantly attenuated these increases (P < 0.01), which was dose-dependent. CONCLUSION: AFS has immunity modulation function and mechanism of it is corrected with Foxp3 mRNA on splenocytes.

Association of PD-1 expression on CD4~+CD25~(nt/hi)CD127~(lo) regulatory T cells with disease progression in HIV-1 infected patients / 细胞与分子免疫学杂志

AIM: To investigate whether Programmed death-1 (PD-1) expression on peripheral CD4~+CD25~(nt/hi)CD127~(lo) regulatory T cells (Treg) was associated with disease progression in HIV-1-infected patients. METHODS: Peripheral blood from 108 HIV-1-infected patients in distinct disease progression statuses and 27 healthy individuals were collected in the present investigation. PBMCs were isolated by centrifugation on Ficoll-Hypaque, followed by staining with anti-CD4-PerCP, anti-CD25-FITC, anti-CD127-PE and anti-PD-1-APC. PD-1 expression on Treg was analyzed by four-color staining flow cytometry. CD4~+T cell absolute counts were determined using Multitest CD3/CD4/CD8/CD45 kit and plasma viral loads were detected on NucliSens EasyQ. All data were analyzed using SPSS14.0 software. RESULTS: In peripheral blood of healthy individuals, Treg expressed PD-1 at very low levels (1.72%±0.65%). In contrast, Treg from HIV-1-infected patients showed a significantly increased PD-1 expression (5.33%±2.24%, P<0.01). Moreover, AIDS patients exhibited statistically higher PD-1 expression on Treg (7.87%±2.23%) than newly HIV-1 infected patients (3.22%±1.01%, P<0.05) and patients in progression to AIDS(5.21%±1.72%, P<0.05). PD-1 up-regulation on Treg was closely correlated with reduced CD4~+T cell absolute counts but elevated plasma viral load. CONCLUSION: Overall, we found that PD-1 expression on peripheral Treg was up-regulated and correlated with disease progression in HIV-1-infected patients for the first time. These findings not only extend our understanding of how Treg functions in HIV-1-infected patients but also support the notion that blocking PD-1/PD-L1 interactions may represent a potential therapeutic strategy for HIV-1-infected patients.

Role of CD4~+ CD25~+ regulatory T lymphocytes in the pathogenesis of murine pulmonary tuberculosis / 中华传染病杂志

Objective To investigate the role of CD4 ~+ CD25~+ regulatory T lymphocytes (Treg)in modulating the cellular immune response and pathogenesis of murine pulmonary tuberculosis.Methods Inactivation of Treg was achieved by intraperitoneal injection anti-CD25 (clone PC61,50 μ/mouse) in PC61 group, and rat-IgG (50 μ/mouse) was injected intraperitoneally in control group. All the mice were inoculated intravenously with H37Rv 0. 1 mL (1 × 10~6 CFU) 3 days after Treg inactivation. The effects of Treg inactivation in different tissues were analyzed by flow cytometry. The cellular immune response, pulmonary histopathology and bacterial load were determined in vitro at different time points. The data were compared using homogeneity of variance F test and non-paired t test. Results In spleen, the percentages of Treg/CD4 T lymphocytes in PC61 group and control group were (21. 13± 3. 58)% and (30. 42± 4. 20)%, respectively at day 10 of inoculation (t = 2. 38, P < 0. 05), and those were (16. 12 ± 1. 26)% and ( 17. 34± 1. 62)%,respectively at day 30 of inoculation (t = 0. 84,P>0. 05). The percentages of Foxp3~+/CD4~+ T lymphocytes in PC61 group and control group were (32. 07 ± 3. 95)% and (60. 55 ± 5. 48)%,respectively at day 10 of inoculation (t = 5. 96, P<0. 05). Similar results were achieved in the peripheral blood. Bacillus calmette-guerin (BCG)-specific 1L-17 (ng/L) secreted by murine spleen cells in PC61 group and control group at day 10, 30 and 60 of inoculation were 5. 1± 0.9 vs 0, 43. 1± 10.0 vs5. 9± 2. 8 and 124.8 ± 5.8 vs 102. 5±8. 1, respectively (t = 7. 90, t=5. 10,t = 3. 19; all P<0.05); those of BCG-specific IFN-γ (ng/L) were 28. 4 ± 8. 2 vs 4. 0±1. 3, 685. 9± 128. 6 vs418. 7±20.4 and 310.9±119. 7 vs 32. 8±7. 5, respectively(tO = 4. 21,t = 8. 43, t = 3. 27; all P<0.05);those of TNF-a (ng/L) were 38. 6±5.0 vs 16. 3±4. 0, 112. 9 ±12. 3 vs 71. 5±12. 6 and 86. 2±8. 2vs0, respectively(t = 4. 95, t=3. 33,t/=14.8; all P<0. 05). The lung bacterial load at day 10 of inoculation in PC61 group was lower than that in control group (t = 4. 63, P < 0. 01), but the differences were not significant thereafter. The changes of lung histopathology at late stage of infection (day 120) in PC61 group were less severe than those in control group. Conclusions Murine Tregs increase dramatically after Mycobacterium tuberculosis infection. Treg could inhibit the specific cellular immunity against Mycobacterium tuberculosis, and therefore, may facilitate the persistent infection of Mycobacterium tuberculosis and development of tuberculosis.

Mechanism of regulatory T cell-induced tumor immune tolerance / 国际肿瘤学杂志

regulatory T cell(Treg)is a subset of immunosuppressive Th cell lines with ability to sup-press anti-tumor immunity. Tregs are recruited into local tumor microenvironment by tumor-released chemokine CCL22. Tregs induce Th2-type immune responses which contribute the host ignorance and tolerance to tumor cells via releasing of immunosuppressive cytokines and immunosuppressive receptors. Accumulating evidences indicate that inhibiting Treg can break immune tolerance,and subsequently inhibit the growth and progress of cancer. These discoveries and exploration of Treg provide us a new therapeutic target and strategy with promising clinic application.