The changes of CD4^+CD25^+ regulatory T cells (CD4^+CD25^+ Treg) and Foxp3 mRNA in peripheral blood mononuclear cells (PBMCs) from patients with asthma were investigated in order to elucidate the possible role...The changes of CD4^+CD25^+ regulatory T cells (CD4^+CD25^+ Treg) and Foxp3 mRNA in peripheral blood mononuclear cells (PBMCs) from patients with asthma were investigated in order to elucidate the possible roles of CD4^+CD25^+ Treg in the development of asthma. The peripheral blood samples were collected from 29 healthy controls (normal control group) and 78 patients with asthma which included 30 patients in exacerbation group, 25 patients in persistent group, and 23 patients in remission group. By using flow cytometry and RT-PCR, the CD4^+CD25^+ Treg ratio and Foxp3 mRNA in PBMCs were detected. The CD4^+CD25^+ Treg ratio and Foxp3 mRNA in PBMCs of exacerbation and persistent groups were lower than that of remission and normal control groups (P〈0.05). Although the CD4^+CD25^+ Treg ratio and Foxp3 mRNA of remission group were also lower than that of normal control group, there was no significant difference between them (P〉0.05). As compared with persistent group, exacerbation group had lower CD4^+CD25^+ Treg ratio and Foxp3 mRNA (P〈0.05). It was indicated that the decrease of CD4^+CD25^+ Treg ratio and its function in PBMCs may be responsible for pathogenesis of asthma.展开更多
Objective: To investigate the expression of both thymic regulatory T cells (CD4+CD25+Foxp3+cells, Treg) and thymic stromal lymphopoietin (TSLP) in thymomas accompanying myasthenia gravis. Methods: We used immunohistoc...Objective: To investigate the expression of both thymic regulatory T cells (CD4+CD25+Foxp3+cells, Treg) and thymic stromal lymphopoietin (TSLP) in thymomas accompanying myasthenia gravis. Methods: We used immunohistochemistry and real-time reverse trancription polymerase chain reaction (real-time RT-PCR) techniques to determine Foxp3+ Treg counts and the expression levels of Foxp3 mRNA and TSLP mRNA in thymomas of 23 MG patients and thymuses of 4 healthy controls. Results: The CD4+ Foxp3+ nTreg (natural regulatory T cells) counts in thymomas were significantly lower than those in normal thymuses (P<0.01), and the expression levels of Foxp3 mRNA and TSLP mRNA were also lower in thymomas(P<0.01). Among the thymoma types, type B1 thymoma had the highest Foxp3+ nTreg count and standard values of Foxp3 mRNA and TSLP mRNA. There was a strong positive correlation between the mRNA transcriptional levels of Foxp3 and TSLP. Conclusion: The insufficient expression of Foxp3 in thymoma, which may be caused by decreased transcription of TSLP, may result in the reduction of Tregs and cause autoimmune disorders.展开更多
Immunotherapy may be used for the treatment of glioblastoma multiforme; however, the induced immune response is inadequate when either T cells or dendritic cells are used alone. In this study we established a novel va...Immunotherapy may be used for the treatment of glioblastoma multiforme; however, the induced immune response is inadequate when either T cells or dendritic cells are used alone. In this study we established a novel vaccine procedure in rats, using dendritic cells pulsed with C6 tumor cell lysates in combination with adoptive transfer of T lymphocytes from syngenic donors. On day 21 after tumor inoculation, all the rats were sacrificed, the brains were harvested for calculation of glioma volume, cytolytic T lymphocyte responses were measured by cytotoxic assay, and the frequency of regulatory T lymphocytes (CD4+CD25~FOXP3~) in the peripheral blood was investigated by flow cytometric analysis. The survival rate of rats bearing C6 glioma was observed. Results showed that the co-immunization strategy had significant anti-tumor potential against the pre-established C6 glioma, and induced a strong cytolytic T lymphocyte response in rats. The frequency of peripheral blood CD4*CD25*FOXP3* regulatory T lymphocytes was significantly decreased following the combination therapy, and the rats survived for a longer period. Experimental findings indicate that the combined immunotherapy of glioma cell lysate-pulsed dendritic cell vaccination following adoptive transfer of T cells can effectively inhibit the growth of gliomas in rats, boost anti-tumor immunity and produce a sustained immune response while avoiding the accumulation of CD4+CD25+FOXP3+ regulatory r lymphocytes.展开更多
Glatiramer acetate (GA) is an immunomodulatory peptide drug used to treat multiple sclerosis. Its treatment effect has been expanded to other autoimmune conditions such as uveoretinitis, inflammatory bowel disease, ...Glatiramer acetate (GA) is an immunomodulatory peptide drug used to treat multiple sclerosis. Its treatment effect has been expanded to other autoimmune conditions such as uveoretinitis, inflammatory bowel disease, graft re- jection and hepatic fibrosis. Here, we report that GA was effective in altering the clinical course of diabetes in cyclo- phosphamide (CY)-potentiated non-obese diabetic (CY-NOD) mice. Treatment with GA significantly reduced the dia- betic rate in the mice and ameliorated insulitis, which coincided with increased CD4+CD25+Foxp3+ T cell response in treated mice. GA treatment led to increased expression of transcription factor Foxp3 and elevated production of interleukin-4 (IL-4) both in vivo and in vitro. It was evident that the effect of GA on up-regulation of Foxp3 was me- diated partially through IL-4. IL-4 was found to maintain Foxp3 expression and regulatory function of CD4+CD25+ regulatory T cells (Tregs). This study provides new evidence that GA has treatment potential for type 1 diabetes through the induction of Tregs and that increased IL-4 production is partially responsible for the enhanced Treg's function in GA treatment.展开更多
AIM: To study the mechanisms of hyporesponsiveness of HBV-specific CD4^+ T cells by testing TH1 and TH2 commitment and regulatory T cells. METHODS: Nine patients with chronic hepatitis B were enrolled. Peripheral b...AIM: To study the mechanisms of hyporesponsiveness of HBV-specific CD4^+ T cells by testing TH1 and TH2 commitment and regulatory T cells. METHODS: Nine patients with chronic hepatitis B were enrolled. Peripheral blood mononuclear cells were stimulated with HBcAg or HBsAg to evaluate their potential to commit to TH1 and TH2 differentiation. HBcAg-specific activity of regulatory T cells was evaluated by staining with antibodies to CD4, CD25, CTLA-4 and interleukin-10. The role of regulatory T cells was further assessed by treatment with anti-interleukin-10 antibody and depletion of CD4^+CD25^+ cells. RESULTS: Level of mRNAs for T-bet, IL-12R β2 and IL-4 was significantly lower in the patients than in healthy subjects with HBcAg stimulation. Although populations of CD4^+CD25^highCTLA-4^+ T cells were not different between the patients and healthy subjects, IL-10 secreting cells were found in CD4^+ cells and CD4^+CD25^+ cells in the patients in response to HBcAg, and they were not found in cells which were stimulated with HBsAg. Addition of anti-IL-10 antibody recovered the amount of HBcAgspecific TH1 antibody compared with control antibody (P 〈 0.01, 0.34% ± 0.12% vs 0.15% ± 0.04%). Deletion of CD4^+CD25^+ T cells increased the amount of HBcAgspecific TH1 antibody when compared with lymphoo/tes reconstituted using regulatory T cells (P 〈 0.01, 0.03% ± 0.02% vs 0.18% ± 0.05%).CONCLUSION: The results indicate that the mechanism of T cell hyporesponsiveness to HBcAg includes activation of HBcAg-induced regulatory T cells in contrast to an increase in TH2-committed cells in response to HBsAg.展开更多
Since their discovery two decades ago,CD4+CD25+Foxp3+ regulatory T cells(Tregs) have become the subject of intense investigation by immunologists. Unlike other T cells,which promote an immune response,Tregs actively i...Since their discovery two decades ago,CD4+CD25+Foxp3+ regulatory T cells(Tregs) have become the subject of intense investigation by immunologists. Unlike other T cells,which promote an immune response,Tregs actively inhibit inflammation when activated by their cognate antigen,thus raising hope that these cells could be engineered into a highly targeted,antigenspecific,immunosuppressant therapy. Although Tregs represent less than 10% of circulating CD4+T cells,they have been shown to play an essential role in preventing or limiting inflammation in a variety of animal models and human diseases. In particular,spontaneous intestinal inflammation has been shown to occur in the absence of Tregs,suggesting that there may be a Treg defect central to the pathogenesis of human inflammatory bowel disease(IBD). However,over the past decade,multiple groups have reported no qualitative or quantitative deficits in Tregs from the intestines and blood of IBD patients to explain why these cells fail to regulate inflammation in Crohn's disease and ulcerative colitis. In this review,we will discuss the history of Tregs,what is known about them in IBD,and what progress and obstacles have been seen with efforts to employ them for therapeutic benefit.展开更多
AIM: To elucidate the distribution of CD4^+CD25^+ regulatory T cells (Tregs) in different lymphoid tissues and its local enhancement on tumor growth before and after depletion of CD4^+CD25^+ Tregs. METHODS: Fe...AIM: To elucidate the distribution of CD4^+CD25^+ regulatory T cells (Tregs) in different lymphoid tissues and its local enhancement on tumor growth before and after depletion of CD4^+CD25^+ Tregs. METHODS: Female ICR mice were garaged with benzo[a]pyrene (BaP) to induce forestomach carcinoma. CD4^+CD25^+ Tregs were intraperitoneally depleted with monoclonal antibody PC61. These mice were divided into BaP-only, BaP + IgG, BaP + PC61, and control groups. The forestomach of mice was dissected for histological analysis, and tunnel test was performed for apoptosis of tumor cells. CD4^+CD25^+ Tregs were sorted from different lymphoid tissues and expression of Foxp3, IL-10, and chemokine receptors was analyzed by flow cytometry, semi-quantitative and veal-time polymerase chain reaction. RESULTS: The mice gavaged with only BaP showed increased forestomach papilloma and carcinoma at wk 16 and 32. The proportion of CD4^+CD25^+ Tregs was significantly higher in peri-stomach regional lymph nodes than in other lymphoid tissues. These CD4^+CD25^+ Tregs in regional lymph nodes expressed higher levels of Foxp3 and IL-10, enriched in the CD62L-subset, and CCR1 and CCR5 chemokine receptors. In mice gavaged with BaP + PC61, the number of tumor nodules and tumor volume decreased significantly with massive infiltrating cells and apoptosis of tumor cells. In the draining regional lymph nodes, the number of CD4^+CD25^+ Tregs also decreased significantly. CONCLUSION: Inducible and activated CD4^+CD25^+ Tregs in the draining regional lymph nodes suppress host local immunity during tumor growth. Depletion of CD4^+CD25^+ Tregs can promote host local immunity to suppress tumor growth.展开更多
CD4+CD25+ regulatory T cells (Tregs) and the expression of their molecular markers (GITR, Foxp3) in peripheral blood of the patients with systemic lupus erythematosus (SLE) were investigated in order to reveal...CD4+CD25+ regulatory T cells (Tregs) and the expression of their molecular markers (GITR, Foxp3) in peripheral blood of the patients with systemic lupus erythematosus (SLE) were investigated in order to reveal the pathogenesis of SLE on the cellular and molecular levels. The level of Tregs in peripheral blood was detected by flow cytometry. The expression levels of GITR and Foxp3 mRNA in peripheral blood mononuclear cells (PBMCs) were assayed by reverse transcriptase-polymerase chain reaction (RT-PCR). The level of IL-6 in the plasma was measured by ELISA. Comparisons were made among 3 groups: the active SLE group, the inactive SLE group, and normal control group. The level of Tregs in the active SLE group and the inactive SLE group was significantly lower than in the normal control group (P〈0.01). The level of Tregs in the active group was lower than in the inactive group with the difference being not significant (P〉0.05). The level of Tregs in SLE patients was significantly negatively correlated with the disease active index in SLE (SLEDAI) (r=-0.81, P〈0.01). The expression levels of GITR mRNA in PBMCs of the active SLE group and the inactive SLE group were significantly higher than in the normal control group (P〈0.05), and those of Foxp3 mRNA in SLE patients of both active and inactive SLE groups were significantly lower than in the normal control group (P〈0.05). There was no significant difference in the expression of GITR and Foxp3 mRNA between the active SLE group and inactive SLE group (P〉0.05). The plasma levels of IL-6 in both the inactive SLE group and active SLE group were significantly higher than in the normal control group (P〈0.01). The plasma level of IL-6 in the active SLE group was sig- nificantly increased as compared with that in the inactive SLE group (P〈0.05), and the plasma level of IL-6 in SLE was significantly positively correlated with SLEDAI scores (r=0.58, P〈0.01) and significantly negatively correlated with the ratio of CD4+CD25+ cells/CD4+ cells (r=-0.389, P〈0.05). It was concluded that the levels of Tregs and Foxp3 mRNA in peripheral blood of SLE patients were decreased and the levels of GITR mRNA and plasma IL-6 were increased. The Tregs and their molecular markers GITR, Foxp3 as well as the plasma IL-6 might play an important role in the pathogenesis of SLE.展开更多
Regulatory T cells(T regs) are key elements in immunological self-tolerance.The number of T regs may alter in both peripheral blood and in colonic mucosa during pathological circumstances.The local cellular,microbiolo...Regulatory T cells(T regs) are key elements in immunological self-tolerance.The number of T regs may alter in both peripheral blood and in colonic mucosa during pathological circumstances.The local cellular,microbiological and cytokine milieu affect immunophenotype and function of T regs.Forkhead box P3+ T regs function shows altered properties in inflammatory bowel diseases(IBDs).This alteration of T regs function can furthermore be observed between Crohn's disease and ulcerative colitis,which may have both clinical and therapeutical consequences.Chronic mucosal inflammation may also influence T regs function,which together with the intestinal bacterial flora seem to have a supporting role in colitis-associated colorectal carcinogenesis.T regs have a crucial role in the immunoevasion of cancer cells in sporadic colorectal cancer.Furthermore,their number and phenotype correlate closely with the clinical outcome of the disease,even if their contribution to carcinogenesis has previously been controversial.Despite knowledge of the clinical relationship between IBD and colitis-associated colon cancer,and the growing number of immunological aspects encompassing sporadic colorectal carcinogenesis,the molecular and cellular links amongst T regs,regulation of the inflammation,and cancer development are still not well understood.In this paper,we aimed to review the current data surrounding the role of T regs in the pathogenesis of IBD,colitis-associated colon cancer and sporadic colorectal cancer.展开更多
Regulatory T cells (Treg) play important roles in immune system homeostasis, and may also be involved in tumor immunotolerance by suppressing Th1 immune response which is involved in anti-tumor immunity. We have pre...Regulatory T cells (Treg) play important roles in immune system homeostasis, and may also be involved in tumor immunotolerance by suppressing Th1 immune response which is involved in anti-tumor immunity. We have previously reported that immunization with attenuated activated autologous T cells leads to enhanced anti-tumor immunity and upregulated Thl responses in vivo. However, the underlying molecular mechanisms are not well understood. Here we show that Treg function was significantly downregulated in mice that received immunization of attenuated activated autologous T cells. We found that Foxp3 expression decreased in CD4+CD25+ T cells from the immunized mice. Moreover, CD4+CD25+Foxp3+ Treg obtained from immunized mice exhibited diminished immunosuppression ability compared to those from naive mice. Further analysis showed that the serum of immunized mice contains a high level ofanti-CD25 antibody (about 30 ng/ml, p〈0.01 vs controls). Consistent with a role ofanti-CD25 response in the downregulation of Treg, adoptive transfer of serum from immunized mice to naive mice led to a significant decrease in Treg population and function in recipient mice. The triggering of anti-CD25 response in immunized mice can be explained by the fact that CD25 was induced to a high level in the ConA activated autologous T cells used for immunization. Our results demonstrate for the first time that immunization with attenuated activated autologous T cells evokes anti-CD25 antibody production, which leads to impeded CD4+CD25+Foxp3+ Treg expansion and function in vivo. We suggest that dampened Treg function likely contributes to enhanced Thl response in immunized mice and is at least part of the mechanism underlying the boosted anti-tumor immunity.展开更多
The immune mechanism of Graves' diseases (GD) and the roles of regulator T cells were investigated. In 32 patients with GD (GD group) and 20 healthy volunteers (control group), flow cytometry was used to detect...The immune mechanism of Graves' diseases (GD) and the roles of regulator T cells were investigated. In 32 patients with GD (GD group) and 20 healthy volunteers (control group), flow cytometry was used to detect the proportion of CD4^+CD25^+ cells, MACS to isolate CD4^+ CD25^+ cells, RT-PCR to assay the expression of FOXP3, and ELISA to test the leyel of IL-10, respectively. It was found that there was no significant change in the proportion of CD4^+CD25^+ T cells between GD group and control group (P〉0.05), while secretion of IL-10 and expression of FOXP3 in GD group were lower than control group (P〈0.01 and P〈0.05, respectively). In conclusion, though the proportion of regulatory T cells of peripheral blood lymphocytes in the patients with GD, the functions of them were significantly weakened, which might be a pathogenic factor in GD.展开更多
AIM: To investigate whether CD4(+)CD25(+) regulatory T (Treg) cells play a role in the development of anterior chamber-associated immune deviation (ACAID). METHODS: The dynamic changes in the frequency of CD4(+)D25(+)...AIM: To investigate whether CD4(+)CD25(+) regulatory T (Treg) cells play a role in the development of anterior chamber-associated immune deviation (ACAID). METHODS: The dynamic changes in the frequency of CD4(+)D25(+) T cells, CD4(+)D25(+) FoxP3(+) T cells and CD4(+)CD25(+) PD-1(+) T cells from spleens of mice with ACAID were analyzed by flow cytometry. Foxp3 mRNA expression in purified CD4(+)CD25(+) T cells was analyzed using real-time PCR. The suppressive effect of purified CD4(+)CD25(+) T cells on the proliferation of CD4(+)CD25(-) T cells was evaluated by [H-3] thymidine incorporation. A blocking experiment was performed to further address the role of CD4(+)CD25(+) T cells in ACAID. The expression of IL-10 in purified CD4(+)CD25(+) T cells was evaluated by ELISA. RESULTS: Increased frequencies of CD4(+)CD25(+) T cells, CD4(+)CD25(+) Foxp3(+) T cells and CD4(+)CD25(+) PD-1(+) T cells were observed in ACAID. The CD4(+)CD25(+) T cells from mice with ACAID showed enhanced suppressive effect on the proliferation of CD4(+)CD25(-) T cells. Treatment of BALB/c mice with anti-CD25 antibody after injection of OVA into the anterior chamber significantly inhibited the induction of ACAID. Furthermore, purified CD4(+)CD25(+) T cells from ACAID mice secreted IL-10. CONCLUSION: Our results demonstrate that Treg cells are induced in the mice undergoing ACAID. These Treg cells may play a role in the development of ACAID.展开更多
Transcription factor forkhead box P3(Foxp3)+regulatory T(Treg)cells are receiving increasing attention because this unique subset of T cells is characterized by exerting negative regulatory function of cellular immune...Transcription factor forkhead box P3(Foxp3)+regulatory T(Treg)cells are receiving increasing attention because this unique subset of T cells is characterized by exerting negative regulatory function of cellular immune responses.The resultant suppression of anti-tumor immunity in the tumor microenvironment(TME)is regarded as a major obstacle to immunotherapies in a plethora of cancers.Thus,an integrated understanding of the intrinsic correlation between tumors and Treg cell biology is urgently required.This review focuses on the peculiar biochemical effects of tumor metabolic environments on Tregs and how Tregs orchestrate internal metabolic switches and altered metabolic pathways and molecules to survive and function after the remodeling of homeostasis and specialization,providing new directions for immunotherapies.展开更多
基金This project was supported by a program of Science Project of Hubei Province (No.2003AA301C10).
文摘The changes of CD4^+CD25^+ regulatory T cells (CD4^+CD25^+ Treg) and Foxp3 mRNA in peripheral blood mononuclear cells (PBMCs) from patients with asthma were investigated in order to elucidate the possible roles of CD4^+CD25^+ Treg in the development of asthma. The peripheral blood samples were collected from 29 healthy controls (normal control group) and 78 patients with asthma which included 30 patients in exacerbation group, 25 patients in persistent group, and 23 patients in remission group. By using flow cytometry and RT-PCR, the CD4^+CD25^+ Treg ratio and Foxp3 mRNA in PBMCs were detected. The CD4^+CD25^+ Treg ratio and Foxp3 mRNA in PBMCs of exacerbation and persistent groups were lower than that of remission and normal control groups (P〈0.05). Although the CD4^+CD25^+ Treg ratio and Foxp3 mRNA of remission group were also lower than that of normal control group, there was no significant difference between them (P〉0.05). As compared with persistent group, exacerbation group had lower CD4^+CD25^+ Treg ratio and Foxp3 mRNA (P〈0.05). It was indicated that the decrease of CD4^+CD25^+ Treg ratio and its function in PBMCs may be responsible for pathogenesis of asthma.
文摘Objective: To investigate the expression of both thymic regulatory T cells (CD4+CD25+Foxp3+cells, Treg) and thymic stromal lymphopoietin (TSLP) in thymomas accompanying myasthenia gravis. Methods: We used immunohistochemistry and real-time reverse trancription polymerase chain reaction (real-time RT-PCR) techniques to determine Foxp3+ Treg counts and the expression levels of Foxp3 mRNA and TSLP mRNA in thymomas of 23 MG patients and thymuses of 4 healthy controls. Results: The CD4+ Foxp3+ nTreg (natural regulatory T cells) counts in thymomas were significantly lower than those in normal thymuses (P<0.01), and the expression levels of Foxp3 mRNA and TSLP mRNA were also lower in thymomas(P<0.01). Among the thymoma types, type B1 thymoma had the highest Foxp3+ nTreg count and standard values of Foxp3 mRNA and TSLP mRNA. There was a strong positive correlation between the mRNA transcriptional levels of Foxp3 and TSLP. Conclusion: The insufficient expression of Foxp3 in thymoma, which may be caused by decreased transcription of TSLP, may result in the reduction of Tregs and cause autoimmune disorders.
基金supported by the grant from the National Natural Science Foundation of China,No.30872647
文摘Immunotherapy may be used for the treatment of glioblastoma multiforme; however, the induced immune response is inadequate when either T cells or dendritic cells are used alone. In this study we established a novel vaccine procedure in rats, using dendritic cells pulsed with C6 tumor cell lysates in combination with adoptive transfer of T lymphocytes from syngenic donors. On day 21 after tumor inoculation, all the rats were sacrificed, the brains were harvested for calculation of glioma volume, cytolytic T lymphocyte responses were measured by cytotoxic assay, and the frequency of regulatory T lymphocytes (CD4+CD25~FOXP3~) in the peripheral blood was investigated by flow cytometric analysis. The survival rate of rats bearing C6 glioma was observed. Results showed that the co-immunization strategy had significant anti-tumor potential against the pre-established C6 glioma, and induced a strong cytolytic T lymphocyte response in rats. The frequency of peripheral blood CD4*CD25*FOXP3* regulatory T lymphocytes was significantly decreased following the combination therapy, and the rats survived for a longer period. Experimental findings indicate that the combined immunotherapy of glioma cell lysate-pulsed dendritic cell vaccination following adoptive transfer of T cells can effectively inhibit the growth of gliomas in rats, boost anti-tumor immunity and produce a sustained immune response while avoiding the accumulation of CD4+CD25+FOXP3+ regulatory r lymphocytes.
文摘Glatiramer acetate (GA) is an immunomodulatory peptide drug used to treat multiple sclerosis. Its treatment effect has been expanded to other autoimmune conditions such as uveoretinitis, inflammatory bowel disease, graft re- jection and hepatic fibrosis. Here, we report that GA was effective in altering the clinical course of diabetes in cyclo- phosphamide (CY)-potentiated non-obese diabetic (CY-NOD) mice. Treatment with GA significantly reduced the dia- betic rate in the mice and ameliorated insulitis, which coincided with increased CD4+CD25+Foxp3+ T cell response in treated mice. GA treatment led to increased expression of transcription factor Foxp3 and elevated production of interleukin-4 (IL-4) both in vivo and in vitro. It was evident that the effect of GA on up-regulation of Foxp3 was me- diated partially through IL-4. IL-4 was found to maintain Foxp3 expression and regulatory function of CD4+CD25+ regulatory T cells (Tregs). This study provides new evidence that GA has treatment potential for type 1 diabetes through the induction of Tregs and that increased IL-4 production is partially responsible for the enhanced Treg's function in GA treatment.
基金Supported by Grant from Ministry of Education, Culture, Sports, Science and Technology of Japan, No. 12877084
文摘AIM: To study the mechanisms of hyporesponsiveness of HBV-specific CD4^+ T cells by testing TH1 and TH2 commitment and regulatory T cells. METHODS: Nine patients with chronic hepatitis B were enrolled. Peripheral blood mononuclear cells were stimulated with HBcAg or HBsAg to evaluate their potential to commit to TH1 and TH2 differentiation. HBcAg-specific activity of regulatory T cells was evaluated by staining with antibodies to CD4, CD25, CTLA-4 and interleukin-10. The role of regulatory T cells was further assessed by treatment with anti-interleukin-10 antibody and depletion of CD4^+CD25^+ cells. RESULTS: Level of mRNAs for T-bet, IL-12R β2 and IL-4 was significantly lower in the patients than in healthy subjects with HBcAg stimulation. Although populations of CD4^+CD25^highCTLA-4^+ T cells were not different between the patients and healthy subjects, IL-10 secreting cells were found in CD4^+ cells and CD4^+CD25^+ cells in the patients in response to HBcAg, and they were not found in cells which were stimulated with HBsAg. Addition of anti-IL-10 antibody recovered the amount of HBcAgspecific TH1 antibody compared with control antibody (P 〈 0.01, 0.34% ± 0.12% vs 0.15% ± 0.04%). Deletion of CD4^+CD25^+ T cells increased the amount of HBcAgspecific TH1 antibody when compared with lymphoo/tes reconstituted using regulatory T cells (P 〈 0.01, 0.03% ± 0.02% vs 0.18% ± 0.05%).CONCLUSION: The results indicate that the mechanism of T cell hyporesponsiveness to HBcAg includes activation of HBcAg-induced regulatory T cells in contrast to an increase in TH2-committed cells in response to HBsAg.
文摘Since their discovery two decades ago,CD4+CD25+Foxp3+ regulatory T cells(Tregs) have become the subject of intense investigation by immunologists. Unlike other T cells,which promote an immune response,Tregs actively inhibit inflammation when activated by their cognate antigen,thus raising hope that these cells could be engineered into a highly targeted,antigenspecific,immunosuppressant therapy. Although Tregs represent less than 10% of circulating CD4+T cells,they have been shown to play an essential role in preventing or limiting inflammation in a variety of animal models and human diseases. In particular,spontaneous intestinal inflammation has been shown to occur in the absence of Tregs,suggesting that there may be a Treg defect central to the pathogenesis of human inflammatory bowel disease(IBD). However,over the past decade,multiple groups have reported no qualitative or quantitative deficits in Tregs from the intestines and blood of IBD patients to explain why these cells fail to regulate inflammation in Crohn's disease and ulcerative colitis. In this review,we will discuss the history of Tregs,what is known about them in IBD,and what progress and obstacles have been seen with efforts to employ them for therapeutic benefit.
基金Grant NSC93-2320-B41-010 and NSC93-2314-B-006-112 from the National Science Council, Taiwan, China
文摘AIM: To elucidate the distribution of CD4^+CD25^+ regulatory T cells (Tregs) in different lymphoid tissues and its local enhancement on tumor growth before and after depletion of CD4^+CD25^+ Tregs. METHODS: Female ICR mice were garaged with benzo[a]pyrene (BaP) to induce forestomach carcinoma. CD4^+CD25^+ Tregs were intraperitoneally depleted with monoclonal antibody PC61. These mice were divided into BaP-only, BaP + IgG, BaP + PC61, and control groups. The forestomach of mice was dissected for histological analysis, and tunnel test was performed for apoptosis of tumor cells. CD4^+CD25^+ Tregs were sorted from different lymphoid tissues and expression of Foxp3, IL-10, and chemokine receptors was analyzed by flow cytometry, semi-quantitative and veal-time polymerase chain reaction. RESULTS: The mice gavaged with only BaP showed increased forestomach papilloma and carcinoma at wk 16 and 32. The proportion of CD4^+CD25^+ Tregs was significantly higher in peri-stomach regional lymph nodes than in other lymphoid tissues. These CD4^+CD25^+ Tregs in regional lymph nodes expressed higher levels of Foxp3 and IL-10, enriched in the CD62L-subset, and CCR1 and CCR5 chemokine receptors. In mice gavaged with BaP + PC61, the number of tumor nodules and tumor volume decreased significantly with massive infiltrating cells and apoptosis of tumor cells. In the draining regional lymph nodes, the number of CD4^+CD25^+ Tregs also decreased significantly. CONCLUSION: Inducible and activated CD4^+CD25^+ Tregs in the draining regional lymph nodes suppress host local immunity during tumor growth. Depletion of CD4^+CD25^+ Tregs can promote host local immunity to suppress tumor growth.
基金a grant from the Natural Sciences Foundation of Hubei, China (No. 2007ABA110).
文摘CD4+CD25+ regulatory T cells (Tregs) and the expression of their molecular markers (GITR, Foxp3) in peripheral blood of the patients with systemic lupus erythematosus (SLE) were investigated in order to reveal the pathogenesis of SLE on the cellular and molecular levels. The level of Tregs in peripheral blood was detected by flow cytometry. The expression levels of GITR and Foxp3 mRNA in peripheral blood mononuclear cells (PBMCs) were assayed by reverse transcriptase-polymerase chain reaction (RT-PCR). The level of IL-6 in the plasma was measured by ELISA. Comparisons were made among 3 groups: the active SLE group, the inactive SLE group, and normal control group. The level of Tregs in the active SLE group and the inactive SLE group was significantly lower than in the normal control group (P〈0.01). The level of Tregs in the active group was lower than in the inactive group with the difference being not significant (P〉0.05). The level of Tregs in SLE patients was significantly negatively correlated with the disease active index in SLE (SLEDAI) (r=-0.81, P〈0.01). The expression levels of GITR mRNA in PBMCs of the active SLE group and the inactive SLE group were significantly higher than in the normal control group (P〈0.05), and those of Foxp3 mRNA in SLE patients of both active and inactive SLE groups were significantly lower than in the normal control group (P〈0.05). There was no significant difference in the expression of GITR and Foxp3 mRNA between the active SLE group and inactive SLE group (P〉0.05). The plasma levels of IL-6 in both the inactive SLE group and active SLE group were significantly higher than in the normal control group (P〈0.01). The plasma level of IL-6 in the active SLE group was sig- nificantly increased as compared with that in the inactive SLE group (P〈0.05), and the plasma level of IL-6 in SLE was significantly positively correlated with SLEDAI scores (r=0.58, P〈0.01) and significantly negatively correlated with the ratio of CD4+CD25+ cells/CD4+ cells (r=-0.389, P〈0.05). It was concluded that the levels of Tregs and Foxp3 mRNA in peripheral blood of SLE patients were decreased and the levels of GITR mRNA and plasma IL-6 were increased. The Tregs and their molecular markers GITR, Foxp3 as well as the plasma IL-6 might play an important role in the pathogenesis of SLE.
文摘Regulatory T cells(T regs) are key elements in immunological self-tolerance.The number of T regs may alter in both peripheral blood and in colonic mucosa during pathological circumstances.The local cellular,microbiological and cytokine milieu affect immunophenotype and function of T regs.Forkhead box P3+ T regs function shows altered properties in inflammatory bowel diseases(IBDs).This alteration of T regs function can furthermore be observed between Crohn's disease and ulcerative colitis,which may have both clinical and therapeutical consequences.Chronic mucosal inflammation may also influence T regs function,which together with the intestinal bacterial flora seem to have a supporting role in colitis-associated colorectal carcinogenesis.T regs have a crucial role in the immunoevasion of cancer cells in sporadic colorectal cancer.Furthermore,their number and phenotype correlate closely with the clinical outcome of the disease,even if their contribution to carcinogenesis has previously been controversial.Despite knowledge of the clinical relationship between IBD and colitis-associated colon cancer,and the growing number of immunological aspects encompassing sporadic colorectal carcinogenesis,the molecular and cellular links amongst T regs,regulation of the inflammation,and cancer development are still not well understood.In this paper,we aimed to review the current data surrounding the role of T regs in the pathogenesis of IBD,colitis-associated colon cancer and sporadic colorectal cancer.
基金This work was supported by National Natural Science Foundation of China(No.30671945)Science and Technology Commission of Shanghai Municipality(Nos.06JC14044,05ZR14055,054319928,04DZ14902)+2 种基金Shanghai Municipal Education(No.05BZ26)Shanghai Leading Academic Discipline Project(T0206)Science Foundation of Shanghai Institute of Immunology(No.07-A04,to Ningli Li).
文摘Regulatory T cells (Treg) play important roles in immune system homeostasis, and may also be involved in tumor immunotolerance by suppressing Th1 immune response which is involved in anti-tumor immunity. We have previously reported that immunization with attenuated activated autologous T cells leads to enhanced anti-tumor immunity and upregulated Thl responses in vivo. However, the underlying molecular mechanisms are not well understood. Here we show that Treg function was significantly downregulated in mice that received immunization of attenuated activated autologous T cells. We found that Foxp3 expression decreased in CD4+CD25+ T cells from the immunized mice. Moreover, CD4+CD25+Foxp3+ Treg obtained from immunized mice exhibited diminished immunosuppression ability compared to those from naive mice. Further analysis showed that the serum of immunized mice contains a high level ofanti-CD25 antibody (about 30 ng/ml, p〈0.01 vs controls). Consistent with a role ofanti-CD25 response in the downregulation of Treg, adoptive transfer of serum from immunized mice to naive mice led to a significant decrease in Treg population and function in recipient mice. The triggering of anti-CD25 response in immunized mice can be explained by the fact that CD25 was induced to a high level in the ConA activated autologous T cells used for immunization. Our results demonstrate for the first time that immunization with attenuated activated autologous T cells evokes anti-CD25 antibody production, which leads to impeded CD4+CD25+Foxp3+ Treg expansion and function in vivo. We suggest that dampened Treg function likely contributes to enhanced Thl response in immunized mice and is at least part of the mechanism underlying the boosted anti-tumor immunity.
文摘The immune mechanism of Graves' diseases (GD) and the roles of regulator T cells were investigated. In 32 patients with GD (GD group) and 20 healthy volunteers (control group), flow cytometry was used to detect the proportion of CD4^+CD25^+ cells, MACS to isolate CD4^+ CD25^+ cells, RT-PCR to assay the expression of FOXP3, and ELISA to test the leyel of IL-10, respectively. It was found that there was no significant change in the proportion of CD4^+CD25^+ T cells between GD group and control group (P〉0.05), while secretion of IL-10 and expression of FOXP3 in GD group were lower than control group (P〈0.01 and P〈0.05, respectively). In conclusion, though the proportion of regulatory T cells of peripheral blood lymphocytes in the patients with GD, the functions of them were significantly weakened, which might be a pathogenic factor in GD.
基金National Natural Science Foundation of China(No. 30400487)International Cooperation Project of Guangdong Province, China (No. 2004B50301002) "1135" Talent Doctor Foundation of Daping Hospital,China (No. 2008-2010)
文摘AIM: To investigate whether CD4(+)CD25(+) regulatory T (Treg) cells play a role in the development of anterior chamber-associated immune deviation (ACAID). METHODS: The dynamic changes in the frequency of CD4(+)D25(+) T cells, CD4(+)D25(+) FoxP3(+) T cells and CD4(+)CD25(+) PD-1(+) T cells from spleens of mice with ACAID were analyzed by flow cytometry. Foxp3 mRNA expression in purified CD4(+)CD25(+) T cells was analyzed using real-time PCR. The suppressive effect of purified CD4(+)CD25(+) T cells on the proliferation of CD4(+)CD25(-) T cells was evaluated by [H-3] thymidine incorporation. A blocking experiment was performed to further address the role of CD4(+)CD25(+) T cells in ACAID. The expression of IL-10 in purified CD4(+)CD25(+) T cells was evaluated by ELISA. RESULTS: Increased frequencies of CD4(+)CD25(+) T cells, CD4(+)CD25(+) Foxp3(+) T cells and CD4(+)CD25(+) PD-1(+) T cells were observed in ACAID. The CD4(+)CD25(+) T cells from mice with ACAID showed enhanced suppressive effect on the proliferation of CD4(+)CD25(-) T cells. Treatment of BALB/c mice with anti-CD25 antibody after injection of OVA into the anterior chamber significantly inhibited the induction of ACAID. Furthermore, purified CD4(+)CD25(+) T cells from ACAID mice secreted IL-10. CONCLUSION: Our results demonstrate that Treg cells are induced in the mice undergoing ACAID. These Treg cells may play a role in the development of ACAID.
文摘Transcription factor forkhead box P3(Foxp3)+regulatory T(Treg)cells are receiving increasing attention because this unique subset of T cells is characterized by exerting negative regulatory function of cellular immune responses.The resultant suppression of anti-tumor immunity in the tumor microenvironment(TME)is regarded as a major obstacle to immunotherapies in a plethora of cancers.Thus,an integrated understanding of the intrinsic correlation between tumors and Treg cell biology is urgently required.This review focuses on the peculiar biochemical effects of tumor metabolic environments on Tregs and how Tregs orchestrate internal metabolic switches and altered metabolic pathways and molecules to survive and function after the remodeling of homeostasis and specialization,providing new directions for immunotherapies.