Correlation between the dynamic changes of γδT cells, Th17 cells, CD4+CD25+ regulatory T cells in peripheral blood and pharmacological interventions against bleomycin-induced pulmonary fibrosis progression in mice.

The involvement of γδT cells, Th17 cells, and CD4+CD25+ regulatory T cells (Tregs) is crucial in the progression of pulmonary fibrosis (PF), particularly in maintaining immune tolerance and homeostasis. However, the dynamics of these cells in relation to PF progression, especially under pharmacological interventions, remains poorly understood. This study aims to unravel the interplay between the dynamic changes of these cells and the effect of pharmacological agents in a mouse model of PF induced by intratracheal instillation of bleomycin. We analyzed changes in lung histology, lung index, hydroxyproline levels, and the proportions of γδT cells, Th17 cells, and Tregs on the 3rd, 14th, and 28th days following treatment with Neferine, Isoliensinine, Pirfenidone, and Prednisolone. Our results demonstrate that these drugs can partially or dynamically reverse weight loss, decrease lung index and hydroxyproline levels, and ameliorate lung histopathological damage. Additionally, they significantly modulated the abnormal changes in γδT, Th17, and Treg cell proportions. Notably, on day 3, the proportion of γδT cells increased in the Neferine and Prednisolone groups but decreased in the Isoliensinine and Pirfenidone groups, while the proportion of Th17 cells decreased across all treated groups. On day 14, the Neferine group showed an increase in all three cell types, whereas the Pirfenidone group exhibited a decrease. In the Isoliensinine group, γδT and Th17 cells increased, and in the Prednisolone group, only Tregs increased. By day 28, an increase in Th17 cell proportion was observed in all treatment groups, with a decrease in γδT cells noted in the Neferine group. These shifts in cell proportions are consistent with the pathogenesis changes induced by these anti-PF drugs, suggesting a correlation between cellular dynamics and pharmacological interventions in PF progression. Our findings imply potential strategies for assessing the efficacy and timing of anti-PF treatments based on these cellular changes.

The Association of Circulating CD14++CD16+ Monocytes, Natural Killer Cells and Regulatory T Cells Subpopulations With Phenotypes of Cardiovascular Disease in a Cohort of Peritoneal Dialysis Patients.

The altered expression of immune cells including monocyte subsets, natural killer (NK) cells and CD4+CD25+ regulatory T cells (Tregs) in end-stage kidney disease, affect the modulation of inflammation and immunity with significant clinical implications. The aim of this study was to investigate the profile of specific immune cells subpopulations and their correlations with phenotypes of established cardiovascular disease (CVD), including coronary artery disease (CAD) and heart failure (HF) in peritoneal dialysis (PD) patients. Materials and Methods: 29 stable PD patients and 13 healthy volunteers were enrolled. Demographic, laboratory, bioimpedance measurements, lung ultrasound and echocardiography data were collected. The peripheral blood immune cell subsets analysis was performed using flow cytometry. Results: PD patients compared to normal controls had lower total lymphocytes (22.3 ± 6.28 vs. 31.3 ± 5.54%, p = <0.001) and B-lymphocytes (6.39 ± 3.75 vs. 9.72 ± 3.63%, p = 0.01) as well as higher CD14++CD16+ monocytes numbers (9.28 ± 6.36 vs. 4.75 ± 2.75%, p = 0.0002). PD patients with prevalent CAD had NK cells levels elevated above median values (85.7 vs. 40.9%, p = 0.04) and lower B cells counts (3.85 ± 2.46 vs. 7.2 ± 3.77%, p = 0.03). Patients with increased NK cells (>15.4%) had 3.8 times higher risk of CAD comparing with patients with lower NK cell levels (95% CI, 1.86 - 77.87; p = 0.034). B cells were inversely associated with the presence of CAD (increase of B-lymphocyte by 1% was associated with 30% less risk for presence of CAD (95% CI, -0.71 - 0.01; p = 0.05). Overhydrated patients had lower lymphocytes counts (18.3 ± 4.29% vs. 24.7 ± 6.18%, p = 0.006) and increased NK cells [20.5% (14.3, 23.6) vs. 13.21% (6.23, 19.2), p = 0.04)]. In multiple logistic regression analysis the CRP (OR 1.43; 95% CI, 1.00 - 2.05; p = 0.04)] and lymphocytes counts (OR 0.79; 95% CI, 0.63-0.99; p = 0.04)] were associated with the presence of lung comets. Patients with higher NK cells (>15.4%, n = 15) were more likely to be rapid transporters (D/P creatinine 0.76 ± 0.1 vs. 0.69 ± 0.08, p = 0.04). Patients displaying higher Tregs (>1.79%) were older (70.8 ± 10.7 years vs. 57.7 ± 14.7years, p = 0.011) and had higher nPCR (0.83 ± 0.14 vs. 0.91 ± 0.17, p = 0.09). Conclusion: Future research is required to evaluate the role of immune cells subsets as potential tools to identify patients at the highest risk for complications and guide interventions.

Induction of CD4+CD25+ Regulatory T Cells from In Vitro Grown Human Mononuclear Cells by Sparteine Sulfate and Harpagoside.

Regulatory T cells (Tregs) are key players in the regulation of inflammatory responses. In this study, two natural molecules, namely, sparteine sulfate (SS) and harpagoside (Harp), were investigated for their ability to induce Tregs in human peripheral blood mononuclear cells (PBMCs). PBMCs were isolated from healthy volunteers and grown in the presence or absence of ConA, with TGF-beta, SS or Harp. Expression of the mRNA of FoxP3, TGF-beta, IL-10 and GAPDH was assessed via q-PCR. The expression of Treg markers including CD4, CD25, CD127 and FoxP3 was measured via flow cytometry. The secretion of IL-10 and TGF-beta by cultured cells was assessed by ELISA. Furthermore, the suppressive role of SS and Harp on PBMCs in vitro was tested via allogeneic mixed lymphocyte reaction (MLR). Data obtained show that both compounds increased the expression of FoxP3, TGF-beta and IL-10 mRNA in resting PBMCs but to a lesser extent in activated cells. Moreover, they significantly increased the percent of CD4+CD25+FoxP3+CD127- Tregs in activated and naïve PBMCs. Functionally, both compounds caused a significant reduction in the stimulation index in allogeneic MLR. Together, our data demonstrate for the first time that SS and Harp can induce human Tregs in vitro and therefore have great potential as anti-inflammatory agents.

Dichotomous role of TGF-ß controls inducible regulatory T-cell fate in allergic airway disease through Smad3 and TGF-ß-activated kinase 1.

BACKGROUND: Inducible CD4+CD25+ regulatory T (iTreg) cells can become pathogenic effector cells, enhancing lung allergic responses. OBJECTIVE: We aimed to define the underlying cellular and molecular pathways activated by TGF-ß, which determine the suppressor or enhancing activities of iTreg cells. METHODS: Sensitized wild-type and CD8-deficient (CD8-/-) mice were challenged with allergen. Isolated CD4+CD25- T cells were activated by using anti-CD3/anti-CD28. To generate suppressor iTreg cells, cells were then differentiated in the presence of TGF-ß, whereas IL-17-producing effector T cells were additionally exposed to IL-6. After TGF-ß, Smad3 and TGF-ß-activated kinase 1 (TAK1) kinase levels were monitored. The consequences of inhibiting either kinase were determined in vitro and after transfer into CD8-/- recipients. Quantitative PCR and chromatin immunoprecipitation were used to monitor gene expression and histone modifications at the retinoic acid-related orphan receptor γt (Rorγt) locus. RESULTS: In wild-type mice, iTreg cells suppressed lung allergic responses linked to Smad3-dependent forkhead box P3 (Foxp3) expression and IL-10 production. In the presence of IL-6, iTreg cells converted to TH17 cells, mediating a neutrophil-dependent enhancement of lung allergic responses in CD8-/- mice. Conversion was regulated by TAK1. Inhibition or silencing of TAK1 prevented expression of Rorγt and TH17 differentiation through histone modifications of Rorγt; Foxp3 expression and iTreg cell-mediated suppression remained intact. In the same cell, TGF-ß induced coexpression of Smad3 and TAK1 proteins; in the presence of IL-6, expression of Smad3 and Foxp3 but not TAK1 decreased. CONCLUSION: TGF-ß regulates iTreg cell outcomes through 2 distinct signal transduction pathways: one Smad3 dependent and the other TAK1 dependent. The balance of these pathways has important implications in TH17-mediated autoimmune diseases and neutrophil-dependent asthma.

CD4+CD25+ Tregs as dependent factor in the course of bleomycin-induced pulmonary fibrosis in mice.

The immune system is felt to play an essential role in pulmonary fibrosis (PF). CD4+CD25+ regulatory T cells (Tregs) are crucial in maintaining immune tolerance and immune homeostasis, but their role in the pathogenesis of PF is controversial and still unclear. We here explored the relationship between peripheral blood CD4+CD25+ Tregs and the course of bleomycin-induced PF in mice. Mouse PF models were established by intratracheal instillation of bleomycin. Lung histology, hydroxyproline, Th1/Th2 balanc, CD4+CD25+ Tregse were analyzed at the 3rd，7th，14th，21st and 28th days after instillation. CD4+CD25+ Tregs were also transferred into mice with or without PF by tail vein injection. The trend of CD4+CD25+ Tregs changes was increased firstly, decreased, increased again from 7th to 28th days after bleomycin instillation, which had great relevance with alveolitis and fibrosis scores. There also were high Th1 polarization index from 3rd to 14th days and high Th2 polarization index at 21st and 28th days after bleomycin treatment. CD4+CD25+ Tregs could promote the secretion of Th2 cytokines and inhibit the secretion of Th1 cytokines, allow the Th1/Th2 balance to Th2 direction in PF. Moreover, preventive adoptive transfer of CD4+CD25+ Tregs may ameliorate the process of PF, while acute adoptive transfer of CD4+CD25+ Tregs may aggravate the process of PF. These findings suggested that the dynamic changes of CD4+CD25+ Tregs as dependent factor might designate a different course of PF induced by bleomycin in mice, and might be a selected drug use indicator for therapy of PF.

Intravenous immunoglobulin promotes the proliferation of CD4+CD25+ Foxp3+ regulatory T cells and the cytokines secretion in patients with Guillain-Barré syndrome in vitro.

Intravenous immunoglobulin (IVIg) serves as the first line therapy in Guillain-Barré syndrome (GBS), however, its action mechanism remains unknown. We hereby stimulated peripheral blood mononuclear cells (PBMCs) from patients with GBS and healthy controls using IVIg and an IgG-derived natural Treg epitopes, namely Tregitopes. Our results showed that IVIg significantly promoted both the expansion of CD4+CD25+Foxp3+ regulatory T cells (Tregs) and secretion of IL-10 and TGF-ß1 while Tregitopes promoted secretion of IL-10 and TGF-ß1 only. Further study is necessary to elucidate the molecular mechanism of IVIg and Tregitopes on Tregs and the secretion of IL-10 and TGF-ß1 in GBS.

Shikonin Controls the Differentiation of CD4+CD25+ Regulatory T Cells by Inhibiting AKT/mTOR Pathway.

CD4+CD25+ regulatory T (Treg) cells maintain the function of immune tolerance and the balance of immune cells. Defects in the number and function of Treg cells can induce the development and progression of inflammatory disease. Shikonin, the main active ingredient of Lithospermum, has anti-inflammatory and anti-tumor effects. Shikonin is also an effective drug for the treatment of psoriasis, which is a chronic inflammatory skin disease. However, the underlying mechanism is not yet clear. To evaluate the role of shikonin on the induction of Treg cells, we tested the number and function of Treg cells in vivo and in vitro. Shikonin can effectively promote the differentiation of iTreg cells by inhibiting the AKT/mTOR pathway in vitro. Moreover, in vivo, intragastrically administered shikonin effectively improved lesions in mice with imiquimod-induced psoriasis and increased the number of iTreg cells in the spleen and their secretion. Shikonin significantly increases the expression of Foxp3mRNA in skin of the psorisic mice. Therefore, we expect that shikonin can prevent the development of inflammation and treat psoriasis by regulating iTreg cells. Novel ideas for the treatment of psoriasis are also proposed.

Mass Cytometry Analysis Reveals that Specific Intratumoral CD4+ T Cell Subsets Correlate with Patient Survival in Follicular Lymphoma.

Follicular lymphoma (FL) is an indolent B cell malignancy characterized by an extensive but poorly functional T cell infiltrate in the tumor microenvironment. Using mass cytometry, we identified at least 12 subsets of intratumoral CD4+ T cells, 3 of which were unique to FL biopsies versus control tissues. Of these subsets, the frequency of naive T cells correlated with improved patient survival. Although total PD-1+ T cell numbers were not associated with patient outcome, specific PD-1+ T cell subpopulations were associated with poor survival. Intratumoral T cells lacking CD27 and CD28 co-stimulatory receptor expression were enriched in FL and correlated with inferior patient outcomes. In vitro models revealed that CD70+ lymphoma cells played an important role in expanding this population. Taken together, our mass cytometry results identified CD4+ memory T cell populations that are poorly functional due to loss of co-stimulatory receptor expression and are associated with an inferior survival in FL.

CD4+ CD25+ regulatory T cells promote hepatocellular carcinoma invasion via TGF-ß1-induced epithelial-mesenchymal transition.

BACKGROUND: CD4+ CD25+ regulatory T cells (Tregs), a crucial component of the infiltration of immune cells in tumor microenvironment, are associated with progression and metastasis of hepatocellular carcinoma (HCC). METHODS: The mechanism of Tregs in the invasion and metastasis of HCC was investigated in vivo and in vitro using immunohistochemical analysis, western blot, and quantitative reverse transcription-PCR (qRT-PCR). RESULTS: Analysis of 78 clinical HCC samples indicated that high expression of Tregs was strongly associated with poor cancer-free survival and overall survival of patients. The reduced expression of E-cadherin and enhanced expression of Vimentin and transforming growth factor-beta 1 (TGF-ß1) were found in HCC tissue compared with normal liver tissue. The HCC Hepa1-6 cells were treated with the supernatant of Tregs-conditioned medium (Tregs-CM) to investigate the epithelial-mesenchymal transition (EMT) and TGF-ß1. Western blot and qRT-PCR also showed that down-regulated E-cadherin and up-regulated Vimentin and TGF-ß1 were found in Tregs-CM-treated Hepa1-6 cells. An experiment of tumorigenicity in C57 mice showed larger and heavier tumors in Tregs-CM-treated group than in the control group. Tregs produced higher TGF-ß1 compared with Tregs treated with FOXP3 shRNA. TGF-ß1 with neutralizing antibodies was used to deplete TGF-ß1 in Tregs-CM, which enhanced expression of E-cadherin, reduced expression of Vimentin and TGF-ß1, and decreased migratory and invasive capacity of Hepa1-6 cells. CONCLUSION: Tregs could promote the invasion and migration of Hepa1-6 cells, which are possibly maintained by TGF-ß1-induced EMT. This study showed that the development of therapeutic strategies against TGF-ß1 pathway is valuable in HCC therapy.

Recombinant adiponectin alleviates abortion in mice by regulating Th17/Treg imbalance via p38MAPK-STAT5 pathway.

Recurrent spontaneous abortion is associated with abnormal maternal tolerance to the semi-allogenic fetus, wherein the Th17/Treg axis plays a crucial role. Adiponectin (APN) is an adipocytokine that is shown to be a novel negative T-cell regulator and induce immune tolerance. The CBA/J × DBA/2 mating was used as an abortion-prone model to investigate whether the addition of recombinant adiponectin (rAPN) improves the pregnancy outcome. Recombinant adiponectin therapy reduced the abortion rate in abortion-prone model. It skewed the ability of serum cytokine production toward a Treg bias and induced APN production. Flow cytometry revealed that rAPN administration expanded the splenic CD4+CD25+ regulatory T-cell (Treg) population and reduced the Th17 cell populations in CBA/J × DBA/2 matings. RT-PCR revealed that rAPN administration induced the expression of AdipoR1 and AdipoR2 mRNA at the maternofetal interface. Recombinant adiponectin administration induced FoxP3 and reduced RORγt expressions at the maternofetal interface. In vitro experiment also showed that rAPN treatment enhanced the FoxP3 mRNA and protein expression and decreased the RORγt expression in splenic lymphocytes of abortion-prone mice. Blocking the different signal transduction pathways downstream of APN, p38MAPK inhibitor (SB203580) and STAT5 inhibitor (Pimozide) could abrogate the regulatory effect of rAPN on FoxP3 and RORγt expression, while STAT3 inhibitor (Stattic) and AMPK inhibitor (p5499) did not exert any influence. Thus, the current results demonstrated that rAPN therapy improves pregnancy outcome in a murine model of abortion by expanding the Treg cell population and function and decreasing the Th17 cell population and function via a p38MAPK-STAT5 pathway.

Effect of montelukast on the expression of CD4+CD25+ regulatory T cells in children with acute bronchial asthma.

The aim of this study was to investigate the effect of montelukast on the expression of CD4+CD25+ regulatory T cells in children with acute bronchial asthma. Fifty-six child patients with acute bronchial asthma treated in the Department of Pneumology at the Shangluo Central Hospital were selected and randomly divided into the control group (n=28) and treatment group (n=28). The control group was treated with the conventional therapy of bronchial asthma, while the treatment group received montelukast on the basis of the control group for 7 days. The clinical symptoms, lung function and proportion of CD4+CD25+ regulatory T cells in peripheral T lymphocyte subsets in patients in the two groups were observed. Moreover, the levels of inflammatory factors and immunoglobulin E (IgE) in peripheral blood in both groups were detected. The effective treatment rate in the treatment group was significantly higher than that in the control group (P<0.05), and the forced expiratory volume in 1 sec/forced vital capacity (FEV1/FVC), peak expiratory flow (PEF) and 25% peak expiratory flow (PEF25) in the treatment group were significantly higher than those in the control group (P<0.05). The proportions of CD4+CD25+ regulatory T cells in the two groups after drug therapy were significantly increased. The proportion and content per unit volume of peripheral CD4+CD25+ regulatory T cells in the treatment group were obviously higher than those in the control group (P<0.01). After treatment, the levels of interleukin-4 (IL-4), IL-5 and IL-6 in peripheral blood in the two groups were significantly decreased. However, the levels of transferrin-γ (TFN-γ) and IL-10 were significantly increased (P<0.01). The IgE level in the treatment group was also significantly higher than that in the control group (P<0.01). In conclusion, montelukast can regulate the T helper 1 (Th1)/Th2 balance, increase the expression of CD4+CD25+ regulatory T cells, and improve the airway inflammation caused by acute bronchial asthma and the clinical symptoms and lung function of patients with acute bronchial asthma.

Therapeutic Effect of CD4+CD25+ Regulatory T Cells Amplified In Vitro on Experimental Autoimmune Neuritis in Rats.

BACKGROUND/AIMS: This study aimed to explore whether the adoptive transfusion of autologous CD4+CD25+ regulatory T cells (CD4+CD25+ Tregs) has a therapeutic effect on Experimental autoimmune neuritis (EAN) model rats, and it provides new experimental and theoretical bases for the immunotherapy of Guillain-Barre syndrome (GBS). METHODS: CD4+CD25+ Tregs were sorted from the spleens of rats using immunomagnetic bead separation techniques combined with flow cytometry. Their in vitro inhibitory function was determined using a lymphocyte proliferation inhibition test, and their purity was confirmed by flow cytometry. Cells were stimulated using CD3/CD28 monoclonal antibodies and were cultured in culture medium containing interleukin 2 (IL-2), transforming growth factor-ß (TGF-ß) and rapamycin. After 15 days of amplification, CD4+CD25+ Tregs were collected and transfused into EAN model rats. Changes in the pathology and electron microscopical morphology of rat sciatic nerves in the normal group, untreated group, low-dose group (2 × 107) and high-dose group (4 × 107) were observed, and the expression of CD4+CD25+FOXP3 in peripheral blood in the four groups of rats was detected by flow cytometry. RESULTS: Compared with rats in the untreated group, rats in the treatment groups had significantly reduced infiltration of inflammatory cells in the sciatic nerve, as well as myelin and axonal damage. Additionally, the CD4+CD25+ Tregs levels in peripheral blood were significantly higher than those in the untreated group (P< 0. 05). Moreover, the therapeutic effect became more significant with an increase in the dose of adoptive transfusion. CONCLUSION: Adoptive transfusion of CD4+CD25+ Tregs into EAN model rats has significant therapeutic effects.

The immunosuppressive effects of CD4+ CD25+ regulatory T cells on dendritic cells in patients with chronic hepatitis B.

The characteristics and functions of CD4+ CD25+ regulatory T cells (Tregs) have been well defined in murine and human systems. However, the interaction or crosstalk between CD4+ CD25+ Tregs and dendritic cells (DCs) remains controversial. In this study, the effects of chronic hepatitis B (CHB) CD4+ CD25+ Tregs on the maturation and function of monocyte-derived DCs were examined. The results showed that CD4+ CD25+ render the DCs inefficient as antigen-presenting cells (APCs) despite prestimulation with CD40 ligand. This effect was marginally reverted by applying neutralizing antibodies (Abs) to IL-10 and TGF-ß. There were an increased IL-10 and TGF-ß secretion and reduced expression of costimulatory molecules in DC. Thus, in addition to a direct suppressor effect on CD4+ T cells, CD4+ CD25+ may modulate the immune response through DCs in CHB patients.

The regulation of regulation: interleukin-10 increases CD4+ CD25+ regulatory T cells but impairs their immunosuppressive activity in murine models with schistosomiasis japonica or asthma.

CD4+ CD25+ Foxp3+ regulatory T (Treg) cells play an important role in maintaining immune homeostasis. Interleukin-10 (IL-10), a cytokine with anti-inflammatory capacities, also has a critical role in controlling immune responses. In addition, it is well known that production of IL-10 is one of the suppression mechanisms of Treg cells. However, the action of IL-10 on Treg cells themselves remains insufficiently understood. In this study, by using a Schistosoma japonicum-infected murine model, we show that the elevated IL-10 contributed to Treg cell induction but impaired their immunosuppressive function. Our investigations further suggest that this may relate to the up-regulation of serum transforming growth factor (TGF-ß) level but the decrease in membrane-bound TGF-ß of Treg cells by IL-10 during S. japonicum infection. In addition, similar IL-10-mediated regulation on Treg cells was also confirmed in the murine model of asthma. In general, our findings identify a previously unrecognized opposing regulation of IL-10 on Treg cells and provide a deep insight into the precise regulation in immune responses.

The levels of CD4+CD25+ regulatory T cells in patients with allergic rhinitis.

BACKGROUND: The involvement of CD4+CD25+ regulatory T cells (CD4+CD25+ TRegs) in allergic diseases was reported previously. However, it remains unclear whether CD4+CD25+ TRegs are involved in allergic rhinitis (AR). METHODS: Fresh whole blood from 20 patients with AR and 16 healthy donors was used to investigate the frequency of CD4+CD25+ and CD4+CD25hi Treg cells using flow cytometry. In addition, serum total IgE (IU/mL) levels were determined using enzyme-linked immunosorbent assays. RESULTS: Patients with AR had fewer CD4+CD25+ Treg cells (2.80 ± 1.36% vs. 3.94 ± 0.97%, P < 0.01) and CD4+CD25hi TRegs (1.53 ± 0·62% vs. 2.00 ± 0.52%, P < 0.05) than control subjects. The number of CD4+CD25+ and CD4+CD25hi TRegs was correlated negatively with total immunoglobulin E levels (r = -0.79, P < 0.01 and r = -0.61, P < 0.01, respectively). CONCLUSION: Deficient regulatory T cells might play a role in the development of AR.

The role of macrophages in the differentiation process of ureteral polyps.

Objective To evaluate the role of macrophage infiltration in the differentiation process of ureteral polyps and cancers. Methods This retrospective immunohistochemical study analysed archival samples of pathologically-confirmed specimens of low- and high-grade ureteral cancer, ureteral papilloma and ureteral polyps. The samples were immunohistochemically stained for cluster of differentiation (CD)4, CD8, CD16, CD25, CD56 and CD68 using immunofluorescence in order to identify different T-lymphocyte populations and macrophages. Results A total of 70 specimens were included in the analysis: 21 specimens of ureteral cancer, 17 specimens of ureteral papilloma, and 32 specimens of ureteral polyps. The largest proportion of CD4+CD25+ regulatory T cells was observed in the low-grade ureteral cancer group and almost none were observed in ureteral papillomas. The largest proportion of CD8+ cytotoxic T-lymphocytes was observed in the ureteral polyps. The largest proportion of CD56+ natural killer cells was detected in the ureteral polyps, with very low levels observed in the other three groups. The largest proportion of CD16+CD68+ macrophages was observed in the high-grade ureteral cancer group, which was significantly higher than that observed in the ureteral papillomas. Conclusions This study revealed that CD16+CD68+ macrophages appear to participate in ureteral neoplastic transformation.

Correlation between unexplained recurrent spontaneous abortion with CD4+CD25+ regulatory T-cell and killer cell immunoglobulin-like receptor levels.

The present study investigated the correlation between unexplained recurrent spontaneous abortion (URSA) with CD4+CD25+ regulatory T-cell (Treg) and killer cell immunoglobulin-like receptor (KIR)-2DL1 levels. A total of 76 URSA patients were enrolled (35 without pregnancy, Group A, and 41 with early abortion, Group B). Additionally, 30 patients who received a regular abortion as planned (Group C) and 30 healthy volunteers (Group D) were selected. Peripheral venous blood and fresh decidual tissue samples were obtained from all the patients, and flow cytometry was performed to detect CD4+CD25+Treg and Foxp3 transcription factor levels. mRNA and protein KIR-2DL1 expression levels were assayed using quantitative PCR and western blot analysis, respectively. No statistically significant differences in peripheral venous blood CD4+CD25+Treg/CD4+ and Foxp3+/CD4+CD25+Treg cell proportions were found among the groups (P>0.05). However, the decidual tissues of Group C presented significantly higher levels of both cell types versus other groups (P<0.05). No statistically significant differences were found in comparisons among Groups A, B, and D (P>0.05). In peripheral venous blood, mRNA and protein KIR-2DL1 expression levels in Group C were significantly higher than those in the other three groups (P<0.05), but again, there were no statistically significant differences among Groups A, B, and D (P>0.05). In decidual tissues, KIR-2DL1 levels were significantly higher in Group C relative to Groups A, B, and D (P<0.05). Decreased CD4+CD25+Treg counts and KIR-2DL1 expression levels were closely associated with the onset of URSA. CD4+CD25+Tregs mainly exert their effects on decidual tissues, while KIR-2DL1 can act on peripheral venous blood and decidual tissues. These may present new targets for early intervention in URSA.

Analysis of clinical effects and mechanism of recombinant human interleukin-11 with glucocorticoids for treatment of idiopathic thrombocytopenic purpura.

The aim of the present study was to evaluate the effectiveness and safety of recombinant human interleukin-11 (IL-11) with glucocorticoids for treatment of adult idiopathic thrombocytopenic purpura (ITP) and the regulatory effect on immune mechanisms. A total of 80 patients with initial diagnosis of ITP admitted to our hospital were selected. Patients were randomly divided into the control group and observation group, with 40 cases each. The control group received glucocorticoids treatment, and the observation group received IL-11 and glucocorticoids. The treatment effects were compared. The total effective rate and effective degree of the observation group was higher than in the control group and the difference was statistically significant (P<0.05); comparing the incidence of complications of the two groups, there was no statistical difference (P>0.05). In the observation group, onset time was reduced, platelet recovery level increased and platelet antibody positive rate decreased, and the differences were statistically significant (P<0.05). The total treatment course was shorter and recurrence rate was lower in the observation group compared with the control group, and the differences were statistically significant (P<0.05). The percentage of CD4+CD25+ regulatory T cells decreased in the two groups after treatment, and was more pronounced in the observation group. The difference was statistically significant (P<0.05). In conclusion, IL-11 with glucocorticoids for the treatment of adult ITP is safe and effective, and may be associated with decreased percentage of CD4+CD25+ regulatory T cells.

Peroxisome proliferator-activated receptor alpha deficiency impairs regulatory T cell functions: Possible application in the inhibition of melanoma tumor growth in mice.

Regulatory T (Treg) cells are important to induce and maintain immunological self-tolerance. Although the progress accomplished in understanding the functional mechanism of Treg cells, intracellular molecules that control the mechanisms of their suppressive capacity are still on investigation. The present study showed that peroxisome proliferator-activated receptor-alpha deficiency impaired the suppressive activity of Treg cells on CD4+CD25- and CD8+ T cell proliferation. In Treg cells, PPARα gene deletion also induced a decrease of migratory abilities, and downregulated the expression of chemokine receptors (CCR-4, CCR-8 and CXCR-4) and p27KIP1 mRNA. Treg cells from PPARα-/- mice also lost their anergic property. Since low Treg activity, as observed in PPARα-/- mice, is known to be associated with the inhibition of tumor growth, we inoculated these mice with B16 melanoma cells and assessed tumor proliferation. In PPARα-/- mice, cancer growth was significantly curtailed, and it was correlated with high expression of granzyme B and perforin mRNA in tumor bed. Degranulation of cytolytic molecules by CD8+ T cells, assessed by a perforin-release marker CD107a expression, was higher in PPARα-/- mice than that in wild-type mice. Tumor-infiltrating lymphocytes (TIL) in melanoma tumors in PPARα-/- mice exhibited high pro-inflammatory Th1 phenotype. Consistently, adoptive transfer into lymphopenic RAG2-/- mice of total PPARα-/-splenic T cells inhibited more the growth rate of B16 tumor than the wild type splenic T cells. Our findings suggest that PPARα deficiency, by diminishing Treg cell functions and upregulating pro-inflammatory T cell phenotype, exerts an in vivo anti-cancer properties.

Impaired NK cells' activity and increased numbers of CD4 + CD25+ regulatory T cells in multidrug-resistant Mycobacterium tuberculosis patients.

Multidrug-resistant tuberculosis (MDR-TB) often causes persistent infection and chemotherapy failure, which brings heavy burden of society and family. Many immune cell subsets and regulatory mechanisms may operate throughout the various stages of infection. The presence of regulatory T cells (Tregs) is thought to be an important mechanism that TB successfully evades the immune system. Tregs play a central role in the prevention of autoimmunity and in the control of immune responses. The role of Tregs in MDR-TB infection and persistence is inadequately documented. The current study was designed to determine whether CD4 + CD25+ regulatory T cells may modulate innate immunity (such as NK cells) against human tuberculosis. Our results indicated that the numbers of CD4 + CD25+ Treg cells increased in MDR-TB patients' blood, and the cytokine production of IL-10 increased from MDR-patients compared with healthy subjects, along with the lower activity and low CD69 expression of NK cells in patients. These results suggested that immunity to MDR-TB patients induced circulating CD4 + CD25+ T regulatory cells expansion, which may be related to the persistence of Mycobacterium tuberculosis (M. tb) infection, and to the balance between effectors immune responses and suppression immune responses.