反复呼吸道感染（RRTI）是小儿时期的常见病,其发生的原因与诸多因素有关。CD4＋CD25＋T调节细胞（regulatory T cell,Tr/Treg）是一个具有独特免疫调节功能的T细胞亚群。此亚群细胞可抑制性调节CD4＋或CD8＋T细胞活化与增殖,在免疫应...反复呼吸道感染（RRTI）是小儿时期的常见病,其发生的原因与诸多因素有关。CD4＋CD25＋T调节细胞（regulatory T cell,Tr/Treg）是一个具有独特免疫调节功能的T细胞亚群。此亚群细胞可抑制性调节CD4＋或CD8＋T细胞活化与增殖,在免疫应答中发挥调节作用[1]。目前对CD4＋CD25＋CD127-调节性T细胞（Treg细胞）与RRTI的相关研究报道较少。展开更多
目的探讨半乳凝素-10(galectin-10)在CD4+CD25+CD127low/-调节性T细胞(regulatory T cell,Treg)中的表达及其与Foxp3的相关性。方法通过流式细胞术分选健康人外周血和胃癌患者癌旁淋巴结中Treg细胞与CD4+CD25-CD127+T细胞,经微量抽提RNA...目的探讨半乳凝素-10(galectin-10)在CD4+CD25+CD127low/-调节性T细胞(regulatory T cell,Treg)中的表达及其与Foxp3的相关性。方法通过流式细胞术分选健康人外周血和胃癌患者癌旁淋巴结中Treg细胞与CD4+CD25-CD127+T细胞,经微量抽提RNA后,用RT-PCR检测galectin-10和Foxp3的mRNA表达水平。结果galectin-10和Foxp3的mRNA显著表达于Treg细胞,几乎不表达于CD4+CD25-CD127+T细胞。健康人外周血和胃癌患者癌旁淋巴结中的结果一致。结论ga-lectin-10基因高表达于Treg细胞中,可以作为Treg细胞一项新的标志物。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
AIM： To investigate the changes of lymphocyte subpopulations, especially CD4^＋CD25^ T regulatory cells in Smad3^-/- mice. METHODS： Hematological changes and changes of lymphocyte subpopulations were detected in Sm...AIM： To investigate the changes of lymphocyte subpopulations, especially CD4^＋CD25^ T regulatory cells in Smad3^-/- mice. METHODS： Hematological changes and changes of lymphocyte subpopulations were detected in Smad3＂/- mice using cell counter and flow cytometry, respectively, and compared to their littermate controls. RESULTS： The numbers of neutrophils and lymphocytes in peripheral blood were significantly increased in Smad3^-/- mice compared to littermate controls. CD19^＋ expressing cells in blood and spleen, and CD8^＋ T cells in thymus were all markedly decreased in Smad3^-/- mice. More important, Smad3^-/- mice had an increased population of CD4^＋CD25^＋ T cells in peripheral lymphoid tissues, including thymus, spleen, and lymph nodes. CONCLUSION： These observations suggest that the changes of lymphocyte subpopulations might play a role in susceptibility to inflammation of Smad3^-/- mice.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
OBJECTIVE CD4^＋CD25^＋ T regulatory （Treg） cells are a population of T cells which suppress an overactive immune system. CCR4 is a chemokine receptor involved in the recruitment of lymphocytes. Nasopharyngeal carci...OBJECTIVE CD4^＋CD25^＋ T regulatory （Treg） cells are a population of T cells which suppress an overactive immune system. CCR4 is a chemokine receptor involved in the recruitment of lymphocytes. Nasopharyngeal carcinoma （NPC） is resistant to immunosurveillance, owing to the increased number of tumor-infiltrating Treg cells which are recruited to the tumor bv CCR4.展开更多
Objective： To establish a stable and high efficient method for collection of CD4^＋CD25^＋ regulatory T cells from rats in vitro. Methods： CD4^＋CD25^＋ regulatory T cells were isolated from the rat splenic cells th...Objective： To establish a stable and high efficient method for collection of CD4^＋CD25^＋ regulatory T cells from rats in vitro. Methods： CD4^＋CD25^＋ regulatory T cells were isolated from the rat splenic cells through two steps by magic cell sorting （MACS） system. The first step was negative selection of CD4^＋T cells by cocktail antibodies and anti-IgG magic microbeads, and the second step was positive selection of CD25^＋T cells by anti-CD25 PE and anti-PE magic microbeads. The purity and viability of separated cells were measured by flow cytometry （FACS） and Trypan blue staining. The suppressive ability of seperated cells on the proliferation of CD4^＋CD25^- T cells was assessed by cell proliferation assay. Results： The purity of negatively enriched CD4^＋ T cells was 79%-87% （83.6%±2.5% ） , and the purity of positively enriched CD4^＋CD25^＋ T cells was 86%- 93% （ 90.2±1.8% ） with the viability of 92%～95% （92.8% ± 3.4% ）. The enriched cells significantly suppressed the proliferation of CD4^＋CD25^- T cells in mixed lymphocyte culture （P 〈 0.05）. Conclusion： An effective method can be established for enrichment of CD4^＋CD25^＋ regulatory T cells in two steps by MACS, with satisfied cell purity, viability and function.展开更多
文摘反复呼吸道感染（RRTI）是小儿时期的常见病,其发生的原因与诸多因素有关。CD4＋CD25＋T调节细胞（regulatory T cell,Tr/Treg）是一个具有独特免疫调节功能的T细胞亚群。此亚群细胞可抑制性调节CD4＋或CD8＋T细胞活化与增殖,在免疫应答中发挥调节作用[1]。目前对CD4＋CD25＋CD127-调节性T细胞（Treg细胞）与RRTI的相关研究报道较少。
文摘目的探讨半乳凝素-10(galectin-10)在CD4+CD25+CD127low/-调节性T细胞(regulatory T cell,Treg)中的表达及其与Foxp3的相关性。方法通过流式细胞术分选健康人外周血和胃癌患者癌旁淋巴结中Treg细胞与CD4+CD25-CD127+T细胞,经微量抽提RNA后,用RT-PCR检测galectin-10和Foxp3的mRNA表达水平。结果galectin-10和Foxp3的mRNA显著表达于Treg细胞,几乎不表达于CD4+CD25-CD127+T细胞。健康人外周血和胃癌患者癌旁淋巴结中的结果一致。结论ga-lectin-10基因高表达于Treg细胞中,可以作为Treg细胞一项新的标志物。
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.
文摘AIM： To investigate the changes of lymphocyte subpopulations, especially CD4^＋CD25^ T regulatory cells in Smad3^-/- mice. METHODS： Hematological changes and changes of lymphocyte subpopulations were detected in Smad3＂/- mice using cell counter and flow cytometry, respectively, and compared to their littermate controls. RESULTS： The numbers of neutrophils and lymphocytes in peripheral blood were significantly increased in Smad3^-/- mice compared to littermate controls. CD19^＋ expressing cells in blood and spleen, and CD8^＋ T cells in thymus were all markedly decreased in Smad3^-/- mice. More important, Smad3^-/- mice had an increased population of CD4^＋CD25^＋ T cells in peripheral lymphoid tissues, including thymus, spleen, and lymph nodes. CONCLUSION： These observations suggest that the changes of lymphocyte subpopulations might play a role in susceptibility to inflammation of Smad3^-/- mice.
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.
基金the National Natural Science Foundation of China
文摘OBJECTIVE CD4^＋CD25^＋ T regulatory （Treg） cells are a population of T cells which suppress an overactive immune system. CCR4 is a chemokine receptor involved in the recruitment of lymphocytes. Nasopharyngeal carcinoma （NPC） is resistant to immunosurveillance, owing to the increased number of tumor-infiltrating Treg cells which are recruited to the tumor bv CCR4.
基金135 Medical Emphasis Grant from Government of Jiangsu Province (135-43)
文摘Objective： To establish a stable and high efficient method for collection of CD4^＋CD25^＋ regulatory T cells from rats in vitro. Methods： CD4^＋CD25^＋ regulatory T cells were isolated from the rat splenic cells through two steps by magic cell sorting （MACS） system. The first step was negative selection of CD4^＋T cells by cocktail antibodies and anti-IgG magic microbeads, and the second step was positive selection of CD25^＋T cells by anti-CD25 PE and anti-PE magic microbeads. The purity and viability of separated cells were measured by flow cytometry （FACS） and Trypan blue staining. The suppressive ability of seperated cells on the proliferation of CD4^＋CD25^- T cells was assessed by cell proliferation assay. Results： The purity of negatively enriched CD4^＋ T cells was 79%-87% （83.6%±2.5% ） , and the purity of positively enriched CD4^＋CD25^＋ T cells was 86%- 93% （ 90.2±1.8% ） with the viability of 92%～95% （92.8% ± 3.4% ）. The enriched cells significantly suppressed the proliferation of CD4^＋CD25^- T cells in mixed lymphocyte culture （P 〈 0.05）. Conclusion： An effective method can be established for enrichment of CD4^＋CD25^＋ regulatory T cells in two steps by MACS, with satisfied cell purity, viability and function.
