Regulatory T cells (Treg) are critical for regulation of tolerance, control immune responses to self-antigens thereby preventing autoimmunity, and limiting responses to foreign antigens thereby minimizing T cell-mediated immunopathology. Recent data indicate that suppression of organ-specific autoimmunity is dependent on the antigen specificity of Treg. An emerging model of Treg action is that organ-specific Treg acquire suppressive activity through activation by dendritic cells expressing specific antigens. Thus, the efficacy of Treg-based therapy should be increased by using antigen-specific Treg rather than polyclonal Treg. It is necessary to identify relevant antigens and to expand antigen-specific Treg from polyclonal populations. Here, we discuss recent techniques for expansion of antigen-specific Treg, function and antigen specificity of Treg and the therapeutic potential of Treg in controlling autoimmune disease and inducing transplant tolerance.
Objective To investigate the efficacy of continuous blood purification ( CBP) in the treatment of severe sepsis, and explore the related immune regulatory mechanisms. Methods Forty-eight patients with severe sepsis were randomly divided into a control group ( n =23) and a CBP group ( n =25) .CD4 + CD25 + regulatory T cells ( Treg% ) in peripheral blood and APACHEⅡ score were measured dynamically before treatment and 12, 24, 36, 48, 60, 72 hours after treatment. Meanwhile the length of ICUstay, duration of mechanical ventilation, and 28 day mortality were determined. Results Compared with the control group, the length of ICU stay, ventilator time, incidence of multiple organ failure, and mortality decreased significantly in the CBP group ( P lt; 0. 05) . And CBP also decreased Treg% and APACHEⅡ score significantly. There was a positive correlation between Treg% and APACHEⅡ score ( r =0. 804, P lt;0. 01) .Conclusion Early CBP treatment can reduce Treg%, improve cellular immunity and improve the prognosis of sepsis.
ObjectiveTo investigate the expression of CD4+CD25highCD127lowTreg (Treg) and related cytokines in peripheral blood of COPD patients with pulmonary hypertension and explore its clinical significance. MethodsPeripheral blood lymphocytes and serum were collected from 65 COPD patients with chronic pulmonary hypertension (the CPH group) and 20 COPD patients with normal pulmonary artery pressure (the control group). Flow cytometry was used to detect the Treg/CD4+ T cells and calculate its ratio, enzyme-linked immunosorbent assay was used to detect the serum contents of interleukin (IL)-6,IL-10 and tumor necrosis factor α (TNF-α). ResultsTreg can be detected in the peripheral blood of patients of COPD with or without PH, however, the Treg ratio in the CPH group was significantly lower than that in the control group [(7.41±1.12)% vs. (9.04±2.11)%, P<0.05]. Compared with the control group, the IL-10 level was significantly lower [(4.47±0.88)pg/mL vs. (5.18±0.26)pg/mL], while IL-6and TNF-α contents were significantly higher in the CPH group [(7.49±0.95)pg/mL vs. (6.76±0.35)pg/mL, (28.61±9.16)pg/mL vs. (19.64±4.85)pg/mL, P<0.05]. There was a positive correlation between Treg ratio and serum IL-10 level (r=0.41, P<0.05), and negative correlation between Treg ratio and TNF-α or IL-6 contents (r=0.45 or 0.37,P<0.05). The Treg ratio of the patients with severe pulmonary hypertension was lower than that in the patients with mild pulmonary hypertension [(7.42±1.03)% vs. (10.47±2.55)%,P<0.05). ConclusionsContents of Treg and IL-10 decrease while IL-6 and TNF-α increase in peripheral blood of COPD patients with pulmonary hypertension. It suggests that Treg cells and related cytokines may involve in the pathogenesis and progression of CPH. Treg may becomea potential biological prognosis indicator and treatment target of CPH in the future.
Objective To investigate the effects of ulinastatin on Treg/Th17 and immune status in patients with severe sepsis.Methods A total of 80 patients with severe sepsis, who were hospitalized in ICU during October 2011 to July 2012, were randomly divided into a routine group and a ulinastatin group. The patients in the ulinastatin group were intravenously administered 30mg ulinastatin three times per day for 5 days in addition to routine bundle treatment. The expression of Treg, Th17 and HLA-DR were detected on the first day in ICU and 5 days after treatment. 20 healthy individuals served as controls. Results Compared with the control group, the severe sepsis group had overexpression of Treg and Th17 ( P lt;0. 01) , higher ratio of Treg/Th17( P lt;0. 01) , and decreased HLA-DR expression of CD14 monocyte ( P lt; 0. 01) . In the severe sepsis patients, ulinastatin injection reduced the abnormal expression of Treg and Th17 ( P lt; 0. 01) , decreased the ratio of Treg/Th17( P lt; 0. 01) , and improved the expression of HLA-DR ( P lt; 0. 01) more effectively compared with the routine treatment. Ulinastatin also lowered 28-day mortality of the patients with sepsis, but the difference between the ulinastatin group and the routine group was not significant. Conclusions In severe sepsis patients, there were abnormal overexpression of Treg and Th17, imbalance of Treg/Th17, and underexpression of HLA-DR which imply an immune suppression. Ulinastatin can decrease the expression of Treg and Th17, inverses the ratio of Treg/Th17, and improve the expression of HLA-DR, so as to improve the prognosis of severe sepsis patients.
Objective To investigate the percentage of CD4+CD25+ Treg in peripheral blood of patients with severe multiple trauma and systemic inflammatory response syndrome（SIRS） and its effects on cellular immunity and secondary infection.Metheds Peripheral blood of 23 patients with severe multiple trauma was collected in 24 h after SIRS was diagnosed，and flow cytometry was used to determine the percentage of CD4+CD25+ Treg and CD4/CD8 ratio.Simultaneously，in order to explore the cell proliferation，silver staining was used to determine Ag-NORs of leukomonocyte in peripheral blood represented by IS%.In order to investigate the infection in patients，sputum and secretion sample were collected for bacteriological examination on 1 and 5 day after SIRS was established.Forty healthy volunteers were enrolled as control.Results Compared with the control，the percentage of CD4+CD25+ Treg was significant higher[（14.21±3.43）% vs（9.53±3.22），Plt;0.01] and the ratio of CD4/CD8 and IS% were significant lower in patients with severe multiple trauma[（5.94±0.66）% vs（6.74±0.95）%，（1.22±0.25）% vs（1.72±0.36）%，respectively，both Plt;0.01].In those patients（n=14） who developed secondary infection，Treg% was significant higher [（18.69±4.21）% vs（12.58±2.49）%，Plt;0.01]，while IS% and CD4/CD8 were significant lower [（5.79±0.68）% vs（6.15±0.57）%，（1.15±0.25）% vs（1.39±0.25）%，both Plt;0.01].compared to the patients without secondary infection Conlusion CD4+CD25+ Treg is valuable to estimate the cellular immunity and predict secondary infection in patients with severe multiple trauma.
Objective To investigate the anti-rejection effect and the mechanism of triptolide （TPT） on islet allo- grafts in a murine model. Methods BALB/c mice were used as islet donor. C57BL/6 mice were rendered diabetic by streptozotocin （STZ） injection， and transplanted with islets under the left kidney capsule. The recipients were randomly （method of random digits table） divided into three groups （n=8）. The mice in the treatment groups were injected intrap-eritoneally with TPT at 50 μg/kg （low-dose TPT group， L-TPT group） or 100 μg/kg （high-dose TPT group， H-TPT group） daily in the first 5 days and then on alternate days until 14 days；while the mice in control group were given vehicles （1% tween 80）. Blood glucose after operation were monitored. The grafts were defined as rejection when two consecutive reading of blood glucose＞20 mmol/L. The left kidney of three recipients in each group were resected for pathological examination. The proportion of CD4＋CD25＋Foxp3＋ regulatory T cells in spleen tissues were tested by flow cytometry. Results The median survival time of islet allografts from the control group， L-TPT group， and H-TPT group were 12.6 days （9-16 days）， 21.4 days （14-27 days） ， and 27.6 days （19-34 days）， respectivly. The percentageof CD4＋CD25＋Foxp3＋regulatory T cells in spleen tissues of three groups were （5.2±0.6）%， （12.0±1.3）%， and（15.7±1.8）%， respectivly. Compared with control group， the median survival time of islet transplantation in mice exte-nded and the proportion of CD4＋CD25＋Foxp3＋ regulatory T cells in spleen tissues increased （P＜0.05）. Conclusions TPT could increase the percentage of CD4＋CD25＋Foxp3＋ regulatory T cells， reduce the rejection after islet transplanta-tion， and prolong the survival time of islet transplantation in mice. The immunosuppressive effect of TPT shows a dose-dependent.
Objective To investigate the changes of CD4 + CD25 + Foxp3 + regulatory T cells( Treg) in peripheral blood of patients with acute exacerbation of COPD( AECOPD) , and analyze the relationship of CD4 + CD25 + Foxp3 + Treg with insulin resistance. Methods A total of 79 patients with AECOPD were divided into four groups according to disease severity( 11 cases in stage Ⅰ,31 cases in stage Ⅱ,28 cases in stage Ⅲ, an 9 cases in stage Ⅳ) .42 healthy volunteers were recruited as control. Fast blood glucose( FBG) and fast insulin( FINS) were measured for calculating the insulin resistance index. The CD4 + CD25 + Foxp3 + Treg were detected by flow cytometry. The relationship between the proportion and number of CD4 + CD25 + Foxp3 + Treg with insulin resistance was statistically analyzed. Results Compared with the healthy control group, the levels of FBG, FINS, and insulin resistance index in the AECOPD patients were significantly higher ( P lt; 0. 01, P lt; 0. 05) . The proportion and number of CD4 + CD25 + Foxp3 + Treg in peripheral blood decreased significantly( P lt; 0. 01, P lt; 0. 05) . The insulin resistance index increased with the severity of AECOPD while the proportion and number of CD4 + CD25 + Foxp3 + Treg in peripheral blood decreased. The insulin resistance index in the AECOPD patients of stage Ⅲ and Ⅳ were higher than those of stage Ⅰ and Ⅱ. The proportion and number of CD4 + CD25 + Foxp3 + Treg in the AECOPD patients of stage Ⅲ and Ⅳ were significantly lower than those of stage Ⅰ and Ⅱ. Both the proportion and number of CD4 + CD25 + Foxp3 + Treg were negatively correlated with insulin resistance ( r = - 0. 633, - 0. 871, P lt; 0. 01) . Conclusions CD4 + CD25 + Foxp3 + Treg cells might may play important role in modulating insulin resistance in AECOPD. The more serious the disease, the lower the CD4 + CD25 + Foxp3 + Treg and the worse insulin resistance.
ObjectiveTo investigate the levels of regulatory T cells (Treg) and FoxP3 gene in patients with gastric cancer before and after operation. MethodsTwenty patients with definite diagnosis of gastric cancer and 15 healthy volunteers were selected. The levels of Treg and T cell subsets in peripheral blood were determined by detecting of CD4 and CD25 with immunefluorescence stain and flow cytometry, the expressions of FoxP3 mRNA in these Treg were detected by RTPCR technique. The expression of FoxP3 protein in the gastric cancer tissue was measured by immunohistochemistry assay. ResultsThe percentage of Treg cells in total CD4+ T isolated from the patients with gastric cancer was higher than that of healthy volunteers 〔(19.39±5.58)% versus (9.91±3.23)%, Plt;0.01〕, and it markedly decreased after operation 〔（13.50±5.93）% versus (19.39±5.58)%, Plt;0.05〕. The FoxP3 mRNA expression in the patients with gastric cancer was also higher than that of healthy volunteers (0.86±0.03 versus 0.64±0.02, Plt;0.01), and decreased after operation (0.73±0.04 versus 0.86±0.03, Plt;0.05). The percentage of CD4+T cell in mononucleocytes of peripheral blood of patients with gastric cancer was significantly lower than that of healthy volunteers (Plt;0.01), but the difference was not significant between before and after operation. FoxP3 protein expressed in cytoplasm of 13 patients with gastric cancer, in which bly positive in 2 cases, middle positive in 6 cases, weakly positive in 5 cases. FoxP3 protein didn’t express in cytoplasm of 7 patients with gastric cancer. ConclusionsTreg may have a significant effect on the onset and development of gastric cancer through immunosuppressive effect. Tumor tissue is an important initiating agent on Treg proliferation.
Objective To assess the effects of different immunosuppressive drugs on proliferation and function of regulatory T cells (Tregs). Methods We searched MEDLINE (1966 to November 2009), EMbase (from inception to September 2009), and The Cochrane Library (Issue 4, 2009) for clinical and basic research about the effects of various immunosuppressive drugs on Tregs. Data were extracted and methodological quality was assessed by two independent reviewers. Outcome measures for clinical research included blood Tregs levels, acute rejection episodes, and graft function. Outcome measures for basic research included percentage of Tregs proliferation, function, Tregs phenotype, and evidence for possible mechanisms. We analyzed data qualitatively. Results Forty-two studies, including 19 clinical trials and 23 basic studies, were included. The immunosuppressive drugs studied were calcineurin inhibitors (CNIs), Rapa, anti-metabolism drugs, IL-2 receptor-blocking antibodies, T-cell depleting antibodies, and co-stimulation blockade antibodies. Most of the studies were on Rapa and CNIs. Eight basic studies on Rapa and CNIs showed that Rapa could promote the proliferation and function of Tregs, while CNIs could not. Five clinical trials involving a total of 158 patients showed that patients taking Rapa had higher blood concentration of Tregs than those taking CNIs, but no differences were found in graft function (6-42-month follow-up). Conclusion There is substantial evidence that Rapa favors Tregs survival and function. However, the larger number of the blood Tregs in the patients treated with Rapa does not show any correlation with better graft function. Large-sample and high-quality clinical studies with longer follow-up are needed to thoroughly assess the efficacy of immunosuppressive drugs on Tregs and to reveal whether a relationship exists between Tregs and graft function.
Objective To investigate the relationship between blood CD4 + CD25 + regulatory T cells ( Treg cells) and cell immunity in patients with sepsis and its prognostic value.Methods 27 patients with sepsis admitted during August 2007 and August 2008 in ICU were enrolled, while 40 healthy volunteers served as control. According to the clinical outcome after 28 days’ treatment, the sepsis patients were assigned to a death group( n=8) and a survival group ( n =19) . Blood Treg% and CD4 /CD8 were detected by flow cytometry and total AgNOR area/nucleus area per cell ( IS%) was measured by silver nitrate staining and image processing. Results The Treg% in the patients with sepsis was significant higher than that in the normal control [ ( 5. 61 ±1. 60) % vs. ( 0. 78 ±0. 23) % , P lt; 0. 01 ] , while the level of CD4 /CD8 and IS% were significant lower[ CD4 /CD8: ( 1. 09 ±0. 30) vs. ( 1. 71 ±0. 36) , IS% : ( 5. 19 ±1. 07) % vs. ( 6. 76 ±0. 92) % , both P lt; 0. 01] . Significant correlations were found between Treg% and CD4 /CD8( r= - 0. 484, P lt;0. 01) , and between Treg% and IS% ( r = - 0. 588, P lt;0. 01) . Compared with the survival group, Treg% was significant higher [ ( 7. 09 ±1. 17) % vs. ( 5. 00 ±1. 33) % , P lt; 0. 01] , and CD4 /CD8 and IS% were significant lower[ CD4 /CD8: ( 0. 87 ±0. 22) vs. ( 1. 18 ±0. 29) , IS% : ( 3. 97 ±0. 42) % vs. ( 5. 71 ±0. 81) % , both P lt; 0. 01] in the death group. Conlusion Blood Treg% level can reflect the cell immune state of patients with sepsis and is of clinical value to assess the prognosis.