Cellular senescence is a signal transduction process which maintained genomic stability and stopped mammalian cell growth. Furthermore, cellular senescence induces a protective response to a variety of DNA damage. How...Cellular senescence is a signal transduction process which maintained genomic stability and stopped mammalian cell growth. Furthermore, cellular senescence induces a protective response to a variety of DNA damage. However, this process is also associated with apoptosis, upregulated secretion of inflammatory cytokine, and promoted surrounding tissue damage. When cellular senescence accumulates to a certain extent, it triggers geriatric diseases, such as chronic inflammation, immune senescence-associated tumors and incontrollable infections. Cellular senescence gene SENEX, which was cloned in 2004, has been demonstrated to play a unique gatekeeper function in human endothelial cells when stress-induced pre-mature senescence and apoptosis occurr. The phenomenon that CD4+CD25+ Treg cells accumulated in the aged population has been well studied in recent years. Now Treg accumulation related to immune-pathology has attracted more interest. CD4+CD25+ Treg did not decline and age, but accumulated and suppressed immunoreaction. The enhanced Treg number and function may be associated with stress-induced premature senescence-mediated unique cellular senescence protection mechanisms, and SENEX may play a critical role in this process. In this article, we summarize the cellular senescence and SENEX gene in the accumulation and functional activity of CD4+CD25+ Treg in the elderly.展开更多
Objective Age-related increment of the prevalence of CD4^+CD25^+ regulatory T (Treg) cells were described controversially, and whether such changes explain immune dysfunction in the elderly is still unclear. The a...Objective Age-related increment of the prevalence of CD4^+CD25^+ regulatory T (Treg) cells were described controversially, and whether such changes explain immune dysfunction in the elderly is still unclear. The aim of this systematic review is to evaluate the role of the Tregs in immunosenescence. Methods Medline and manual searches were performed to identify all published epidemiological and animal studies investigating the efficacy of the association between immunosenescence and Treg cells. Results It was founded that the frequency, phenotypic characteristics, and number/function of Tregs were altered significantly with aging. Medical conditions in individuals with advanced ageas well as apoptosis intensity of Treg cells had an impact on the accumulation of Tregs which in turn could deteriorate cytotoxic activity of CD8+ T and NK cells and production of IL-2. The range of immune cells that could be suppressed by Treg cells was quite wide and covered CD4^+CD25^+ T cells, NK cells, dendritic cells and even monocytes. These changes were observed both in humans and experimental animals. Besides, it was believed that frequency of Tregs increased with age and was accompanied by intensified suppressive activity for Tregs in patients, for example, with Alzheimer disease (AD) and Parkinson disease (PD). The impaired condition of CD4+ T cells, so-called immunosenescence, rendered transplant recipients less responsive to an allogeneic kidney graft, an effect that was limited to transplant recipients who were aged over 60 years. Conclusions Treg cells are associated with immunosenescence. All these changes contribute to the aging-related decline of immune responses and lead to the higher risk of immune-mediated diseases, cancer or infections in aged individuals.展开更多
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
The function of CD4+CD25+ regulatory T lymphocytes (Treg) in patients with acute coronary syndrome (ACS) and the effects of atorvastatin were investigated. Forty-eight patients with ACS were randomly divided int...The function of CD4+CD25+ regulatory T lymphocytes (Treg) in patients with acute coronary syndrome (ACS) and the effects of atorvastatin were investigated. Forty-eight patients with ACS were randomly divided into two groups: group C receiving conventional therapy (n=24), and group C+A receiving conventional therapy+atorvastatin (10 mg/day, n=24). T lymphocytes from ACS patients (before and 2 weeks after the treatment) or 18 healthy subjects were separated and the flow cytometry was used to measure the percentage of Treg. The inhibitory ability of Treg on effector T cells was determined by mixed lymphocyte reaction (MLR). ELISA was used to measure the serum levels of cytokines (IL-10, TGF-β1 and IFN-γ) before and after treatment. The results showed that as compared with normal control group, Treg percentage was decreased significantly (P〈0.01), the inhibitory ability of Treg on the T lymphocytes proliferation was reduced (P〈0.01), IFN-γ levels were increased and IL-10 and TGF-β1 levels were lowered in ACS patients. After treatment with atorvastatin, Treg percentage and the inhibitory ability of Treg on T lymphocytes proliferation were significantly increased in ACS patients. Serum IFN-γ was decreased significantly, while IL-10 and TGF-β1 were elevated significantly as compared with the non-atorvastatin group. The number of Treg was positively correlated with serum TGF-β1, but negatively with serum IFN-γ and CRP. It was concluded that ACS was associated with decreased number and defected function of Treg, which may play an important role in initiating immune-inflammatory response in ACS. The inhibitory effects of atorvastatin on inflammation in ACS may be due to its beneficial effects on Treg and restoration of immune homeostasis.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
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
Objective: To investigate the influence of Danshen Injection on airway inflammation and CD4^+CD25^+ regulatory T cells(CD4^+CD25^+ Tr) of asthmatic rats, and elucidate the possible mechanism of Danshen Inject...Objective: To investigate the influence of Danshen Injection on airway inflammation and CD4^+CD25^+ regulatory T cells(CD4^+CD25^+ Tr) of asthmatic rats, and elucidate the possible mechanism of Danshen Injection in treatment of asthma. Methods: 30 Wister rats were randomly divided into control group, asthma group and Danshen Injection treated group. Bronchoalveolar lavage fluids (BALF) were collected, and cytology studies were conducted. Lung tissues were obtained and pathologic analyses were done with hematoxylin and eosin stain (HE). Flow cytometry was used to detect the CD4^+CD25^+ Tr ratio in peripheral blood mononuclear cells (PBMCs). Results: Total cell, the percentage of lymphocytes, neutrophils and eosinophils (Eos) in BALF of Danshen Injection-treated group were lower than that in asthma group (P〈0.05, P〈0.01). Compared with asthma group, less infiltration of inflammatory cells in lung tissues was observed in Danshen Injection-treated group. CD4^+CD25^+ Tr of asthma group was lower than that of control and Danshen Injection treated group (P〈0.05). Conclusion: Danshen Injection can suppress airway inflammation of asthmatic rats, probably by increasing the number of CD4^+CD25^+ Tr.展开更多
文摘Cellular senescence is a signal transduction process which maintained genomic stability and stopped mammalian cell growth. Furthermore, cellular senescence induces a protective response to a variety of DNA damage. However, this process is also associated with apoptosis, upregulated secretion of inflammatory cytokine, and promoted surrounding tissue damage. When cellular senescence accumulates to a certain extent, it triggers geriatric diseases, such as chronic inflammation, immune senescence-associated tumors and incontrollable infections. Cellular senescence gene SENEX, which was cloned in 2004, has been demonstrated to play a unique gatekeeper function in human endothelial cells when stress-induced pre-mature senescence and apoptosis occurr. The phenomenon that CD4+CD25+ Treg cells accumulated in the aged population has been well studied in recent years. Now Treg accumulation related to immune-pathology has attracted more interest. CD4+CD25+ Treg did not decline and age, but accumulated and suppressed immunoreaction. The enhanced Treg number and function may be associated with stress-induced premature senescence-mediated unique cellular senescence protection mechanisms, and SENEX may play a critical role in this process. In this article, we summarize the cellular senescence and SENEX gene in the accumulation and functional activity of CD4+CD25+ Treg in the elderly.
基金supported by the National Natural Science Foundation of China (No.30330540)the Jiangsu Provincial Fund for Clinical Immunology Key Laboratory (No.200319)the Scientific and Technological Fund to Support Project of Suzhou City (ZS0901)
文摘Objective Age-related increment of the prevalence of CD4^+CD25^+ regulatory T (Treg) cells were described controversially, and whether such changes explain immune dysfunction in the elderly is still unclear. The aim of this systematic review is to evaluate the role of the Tregs in immunosenescence. Methods Medline and manual searches were performed to identify all published epidemiological and animal studies investigating the efficacy of the association between immunosenescence and Treg cells. Results It was founded that the frequency, phenotypic characteristics, and number/function of Tregs were altered significantly with aging. Medical conditions in individuals with advanced ageas well as apoptosis intensity of Treg cells had an impact on the accumulation of Tregs which in turn could deteriorate cytotoxic activity of CD8+ T and NK cells and production of IL-2. The range of immune cells that could be suppressed by Treg cells was quite wide and covered CD4^+CD25^+ T cells, NK cells, dendritic cells and even monocytes. These changes were observed both in humans and experimental animals. Besides, it was believed that frequency of Tregs increased with age and was accompanied by intensified suppressive activity for Tregs in patients, for example, with Alzheimer disease (AD) and Parkinson disease (PD). The impaired condition of CD4+ T cells, so-called immunosenescence, rendered transplant recipients less responsive to an allogeneic kidney graft, an effect that was limited to transplant recipients who were aged over 60 years. Conclusions Treg cells are associated with immunosenescence. All these changes contribute to the aging-related decline of immune responses and lead to the higher risk of immune-mediated diseases, cancer or infections in aged individuals.
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The function of CD4+CD25+ regulatory T lymphocytes (Treg) in patients with acute coronary syndrome (ACS) and the effects of atorvastatin were investigated. Forty-eight patients with ACS were randomly divided into two groups: group C receiving conventional therapy (n=24), and group C+A receiving conventional therapy+atorvastatin (10 mg/day, n=24). T lymphocytes from ACS patients (before and 2 weeks after the treatment) or 18 healthy subjects were separated and the flow cytometry was used to measure the percentage of Treg. The inhibitory ability of Treg on effector T cells was determined by mixed lymphocyte reaction (MLR). ELISA was used to measure the serum levels of cytokines (IL-10, TGF-β1 and IFN-γ) before and after treatment. The results showed that as compared with normal control group, Treg percentage was decreased significantly (P〈0.01), the inhibitory ability of Treg on the T lymphocytes proliferation was reduced (P〈0.01), IFN-γ levels were increased and IL-10 and TGF-β1 levels were lowered in ACS patients. After treatment with atorvastatin, Treg percentage and the inhibitory ability of Treg on T lymphocytes proliferation were significantly increased in ACS patients. Serum IFN-γ was decreased significantly, while IL-10 and TGF-β1 were elevated significantly as compared with the non-atorvastatin group. The number of Treg was positively correlated with serum TGF-β1, but negatively with serum IFN-γ and CRP. It was concluded that ACS was associated with decreased number and defected function of Treg, which may play an important role in initiating immune-inflammatory response in ACS. The inhibitory effects of atorvastatin on inflammation in ACS may be due to its beneficial effects on Treg and restoration of immune homeostasis.
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.
基金This This work was supported by a grant from the Science and Technology Foundation of Hubei Province (2003AA301C10)
文摘Objective: To investigate the influence of Danshen Injection on airway inflammation and CD4^+CD25^+ regulatory T cells(CD4^+CD25^+ Tr) of asthmatic rats, and elucidate the possible mechanism of Danshen Injection in treatment of asthma. Methods: 30 Wister rats were randomly divided into control group, asthma group and Danshen Injection treated group. Bronchoalveolar lavage fluids (BALF) were collected, and cytology studies were conducted. Lung tissues were obtained and pathologic analyses were done with hematoxylin and eosin stain (HE). Flow cytometry was used to detect the CD4^+CD25^+ Tr ratio in peripheral blood mononuclear cells (PBMCs). Results: Total cell, the percentage of lymphocytes, neutrophils and eosinophils (Eos) in BALF of Danshen Injection-treated group were lower than that in asthma group (P〈0.05, P〈0.01). Compared with asthma group, less infiltration of inflammatory cells in lung tissues was observed in Danshen Injection-treated group. CD4^+CD25^+ Tr of asthma group was lower than that of control and Danshen Injection treated group (P〈0.05). Conclusion: Danshen Injection can suppress airway inflammation of asthmatic rats, probably by increasing the number of CD4^+CD25^+ Tr.