Regulatory Cell Percentage Research Articles

Taurine promotes the production of CD4+CD25+FOXP3+ Treg cells through regulating IL-35/STAT1 pathway in a mouse allergic rhinitis model

BackgroundAllergic rhinitis (AR) is one of the most widespread immune conditions worldwide. However, common treatments often present with significant side effects or are cost-prohibitive for much of the population. A plethora of treatments have been used for the treatment of AR including antihistamines, steroids, and immune modulators. Among the treatments which have shown potential for efficacy in treating AR with a minimum of side effects but remains understudied is the conditionally essential amino acid taurine. Taurine has been previously shown to reduce AR symptoms. Here, we examine the role of taurine in modulating T regulatory cells, modulating the cytokine response in AR, and restoring healthy nasal mucosa.MethodsBlood samples from 20 healthy donors and 20 AR patients were compared for CD4+CD25+FoxP3+ T regulatory (Treg) cell population percentage, cytokine release, and STAT1 signaling with and without taurine treatment or IL-35 neutralization. An OVA-induced AR mouse model was administered vehicle, taurine, or taurine plus an IL-35 neutralizing antibody and assayed for sneezing frequency, inflammatory cytokine response, nasal mucosa goblet cell density, and T regulatory cell percentage. CD4+ cells were further examined for cytokine release, STAT1 phosphorylation, and response to an anti-IL-35 antibody with and without a STAT1 inhibitor.ResultsComparison of blood from normal donors and AR patients showed a reduction in CD4+CD25+FoxP3+ Treg cells in AR patients and a strong correlation between Treg percentage and IL-35 release. A similar pattern of Treg suppression was found in untreated AR mice when compared to normal control mice wherein there was a reduction in Treg percentage and a corresponding decrease in IL-35 release. AR mice also demonstrated increased sneezing frequency, an infiltration of goblet cell in nasal mucosa, and a reduction in IL-35 release from CD4+ cells. Conversely, IL-4, IL-5, and IL-13 secretion from CD4+ cells were increased in AR model mice, as was STAT1 phosphorylation. When AR mice were treated with taurine, sneezing frequency and nasal mucosa goblet cell content were reduced while Treg abundance was increased to that of normal mice. Accordingly, IL-35 release was restored, while IL-4, IL-5, and IL-13 secretion from CD4+ cells were suppressed. Likewise, STAT1 phosphorylation was inhibited with taurine treatment. Taurine-treated mice also given an IL-35 neutralizing antibody exhibited AR pathology including frequent sneezing and high nasal goblet cell content while retaining a restoration of Tregs. Furthermore, murine AR model CD4+ cells exposed to recombinant IL-35 responded with a reduction in inflammatory cytokine release and a decrease in STAT1 phosphorylation, mimicking the effect of taurine treatment.ConclusionsTaurine induces release of IL-35 in AR; IL-35 promotes the production of CD4+CD25+FoxP3+ Treg cells via a STAT1-dependent pathway. The restoration of Treg populations by taurine normalizes the inflammatory response, reduces AR symptomology, and reduces histopathologic signs of AR.

Nigella sativa in controlling Type 2 diabetes, cardiovascular, and rheumatoid arthritis diseases: Molecular aspects.

Oxidative stress is an important factor in the etiology of several chronic diseases that include cardiovascular disease (CVD), Type 2 diabetes (T2D), and rheumatoid arthritis (RA). Oxidative stress can lead to inflammation, and this can contribute to these chronic diseases. Reducing inflammation and oxidative stress may, therefore, be useful in the prevention and treatment of these conditions. One of the treatment options for chronic diseases is the use of traditional medicine and herbs, such as Nigella sativa. This is one of the herbs that have recently been assessed for its ability to reduce inflammation and oxidative stress. We have reviewed the reported effects of N. sativa on risk factors of chronic diseases (CVD, DM, and RA) with emphasis on molecular and cellular mechanisms in controlling inflammation and oxidative stress. Various mechanisms have been proposed to contribute to the beneficial properties of N. sativa, including a reduction of lipid peroxidation via its antioxidant properties; agonist of peroxisome proliferator-activated receptor gamma in adipose tissue; activation of AMP-activated protein kinase, increased antioxidants, inhibition of nuclear factor-kappa B pathway; increased in interleukin-10 expression, CD4+ T-cell percentage, T regulatory cell percentage (CD4+ CD25+ T-cell) in peripheral blood, and CD4+/CD8+ ratio, but to prove this claim, it is necessary to conduct experimental and well-designed clinical trial studies with a larger sample size on the effects of N. sativa on these chronic diseases.

Phase I trial of low-dose interleukin 2 therapy in patients with Wiskott-Aldrich syndrome

BackgroundLow dose IL-2 can restore the function of T and NK cells from Wiskott-Aldrich (WAS) patients. However, the safety of in vivo IL-2 in WAS is unknown. ObjectivesA phase-I study to assess safety of low dose IL-2 in WAS. MethodsPatients received 5 daily subcutaneous IL-2 injections, every 2months, for three courses. A “3+3” dose escalation method was used. Results6 patients received the 0.5millionunits/m2/day dose without serious adverse events. However, 2 of 3 patients receiving the 1millionunits/m2/day dose developed thrombocytopenia requiring platelet transfusions. A statistically significant platelet increase occurred in patients receiving the 0.5millionunits/m2/day dose. A trend toward higher T, B and NK cell numbers and higher T regulatory cell percentages was observed. ConclusionWe have identified a safe IL-2 dose for WAS patients. Additional trials are indicated to study the efficacy of this immunostimulant as a therapy for WAS.

Differential effects of palmitoleic acid on human lymphocyte proliferation and function.

BackgroundPalmitoleic acid (PA) is a n-7 monounsaturated fatty acid (MUFA) secreted by adipose tissue and related to decreased insulin resistance in peripheral tissues. Evidences have been shown that PA also decreased proinflammatory cytokine expression in cultured macrophages. Although studies have shown that other fatty acids (FAs) modulate several lymphocyte functions, the specific effect of PA on these cells is unknown. The aim of the present study was to evaluate the possible influence of PA on activation and differentiation of human lymphocytes in comparison to oleic acid (OA).MethodsHuman lymphocytes were isolated from peripheral blood of health men and cultured in the presence of growing concentrations of PA or OA (5 to 200 μM), for 24 h. After that, cells were collected and cytotoxicity evaluated by flow cytometry. Then, we analyzed proliferative capacity in lymphocytes treated with non toxic concentrations of PA and OA (25 and 50 μM, respectively), in the presence or absence of concanavalin A (ConA). The Th1/Th2/Th17 cytokine production was determined by the Cytometric Bead Array. CD28 and CD95 surface expression and T regulatory cell percentage were determined by flow cytometry.ResultsWe observed that PA is toxic to lymphocytes above 50 μM. PA promoted a decrease of lymphocyte proliferation stimulated by ConA in both concentrations. PA also decreased CD28 externalization and increased CD95. On the other hand, OA did not alter these parameters. In the same way, PA reduced IL6, IFN-gamma, TNF-alpha and IL17A production in both concentration and IL2 only at 50 μM (in the presence of ConA). OA promoted IFN-gamma reduction in both concentrations and an increase of IL-2, IL4 and IL10 at 25 μM. Both fatty acids decreased the percentage of T regulatory cells.ConclusionIn conclusion, PA promoted a suppressive effect on lymphocyte proliferation characterized by a decrease of Th1 and Th17 response, and co-stimulatory molecule (CD28). However, OA increased lymphocyte proliferation through IL2 production and Th2 response. These results also show a more suppressive effect of PA on lymphocytes in comparison to OA.

Abstract 530: Location of oncogene expression within a stratified squamous epithelium drives distinct B and CD4 T-cell crosstalk to dictate the tumor immune response

Abstract Tumors from stratified epithelium contain proliferating and differentiating compartments, but it is not clear how tumor cells in different layers alternatively engage the immune system. We have established two doxycycline inducible Ras models in which oncogenic RasV12G is targeted to either the epidermal basal/stem cell layer with a Keratin14-rtTA transgene (K14Ras), or suprabasal differentiating cells with an Involucrin-tTA transgene (InvRas). On threshold doxycycline levels yielding similar tumor numbers and Ras expression over 30 days, mice with basal cell targeted Ras developed focal squamous cell carcinoma while suprabasal targeting caused benign squamous papilloma formation. On a Rag1-/- background InvRas mice developed fewer tumors that regressed over time while K14Ras mice developed more tumors with shorter latency than Rag1+/+ controls. Depletion and adoptive transfer studies revealed that naïve B and CD4 T cells together, but not alone, suppressed tumor formation in K14Ras mice but restored tumor numbers in InvRas mice. Tumors developing in K14Ras mice showed a loss of proinflammatory CD4 T and B cells and increased percentages of regulatory cells infiltrating the tumor tissue. In vivo cotransfers show that B and CD4 T cells reciprocally prime each other towards a regulatory phenotype in the K14Ras tumor microenvironment, but in the InvRas tumor microenvironment proinflammatory CD4 T and B cell phenotypes result. Coculture of tumor-conditioned B cells with stimulated naïve CD4 T cells showed an importance of direct contact and CD40/CD40L interactions for the generation of regulatory T cells (Tregs) by B cells in K14Ras mice. In contrast, tumor-conditioned B cells from InvRas mice support generation of proinflammatory CD4 T cells, and antagonize Treg development. This function is restricted to tumor-conditioned B cells, as splenic B cells from tumor-bearing mice had no effect on CD4 T cell phenotype. In vivo blockade of CD40L in K14Ras mice resulted in significantly increased tumor counts as well as reduced B and Treg prevalence. Blockade of CD40L in InvRas mice significantly reduced tumor number, increasing Treg cell count and decreasing neutrophil infiltration into the tumor tissue. Time-course experiments suggest a protective role of Tregs in late stages of K14Ras tumors, and a tumor-promoting role of proinflammatory CD4 T cells in InvRas tumors. Thus, basal/stem cell expression of Ras provokes a regulatory cell inducing microenvironment, suppressing tumor-promoting inflammation in late-stage tumors. Ras expression in differentiating cells activates a tumor promoting proinflammatory phenotype in B and CD4 T cells without provoking immunosurveillance. Taken together, these data show that tumor cell position within a stratified epithelium differentiation hierarchy provokes distinct B and CD4 T cell interactions with opposing effects on tumor development. Citation Format: Michael A. Podolsky, Carrie J. Oakes, Andrew Gunderson, Kyle Breech, Jacob Bailey, Adam B. Glick. Location of oncogene expression within a stratified squamous epithelium drives distinct B and CD4 T-cell crosstalk to dictate the tumor immune response. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 530.

Abstract 4052: Location of oncogene expression within a stratified squamous epithelium drives distinct B and CD4 T cell crosstalk to dictate the tumor immune response

Abstract Tumors from stratified epithelium contain both proliferating and differentiating compartments, but it is not clear if tumor cells in different layers engage the immune system in a similar fashion. We have established two doxycycline inducible Ras models in which oncogenic RasV12G is targeted to either the epidermal basal/stem cell layer with a Keratin14-rtTA transgene (K14Ras), or suprabasal differentiating cells with an Involucrin-tTA transgene (InvRas). As expected, on threshold doxycycline levels yielding similar numbers of tumors over 30 days and similar Ras expression, mice with basal cell targeted Ras developed focal squamous cell carcinoma while suprabasal targeting caused benign squamous papilloma formation. However, on a Rag1­-/- background InvRas mice developed fewer tumors that regressed over time while K14Ras mice developed more tumors with shorter latency than Rag1+/+ controls. Depletion and adoptive transfer studies revealed that naïve B and CD4 T cells together, but not alone, suppressed tumor formation in K14Ras mice but restored tumor numbers in InvRas mice. Tumors developing in K14Ras mice showed a progressive loss of proinflammatory CD4 T cells and B cells and increased percentages of regulatory cells infiltrating the tumor tissue. In vivo cotransfers show that B and CD4 T cells reciprocally prime each other towards a regulatory phenotype in the K14Ras tumor microenvironment, while in the InvRas tumor microenvironment there was reciprocal priming of proinflammatory CD4 T and B cell phenotypes. Coculture of tumor-conditioned B cells with stimulated naïve CD4 T cells showed an importance of direct contact for the generation of regulatory T cells by B cells. Surprisingly, tumor conditioned InvRas splenocytes transferred into K14RasRag1-/- mice prior to Ras induction slightly enhanced tumor numbers while tumor conditioned K14Ras splenocytes blocked tumor formation in InvRasRag1-/- mice. Thus, basal/stem cell expression of Ras provokes a regulatory cell inducing microenvironment, which suppresses tumor-promoting inflammation in late-stage tumors. Ras expression in differentiating cells activates a tumor promoting proinflammatory phenotype in B and CD4 T cells without provoking immunosurveillance. Taken together, these data show that tumor cell position within a stratified epithelium differentiation hierarchy provokes distinct B and CD4 T cell interactions with opposing effects on tumor development. Citation Format: Michael A. Podolsky, Carrie J. Oakes, Andrew Gunderson, Kyle Breech, Adam B. Glick. Location of oncogene expression within a stratified squamous epithelium drives distinct B and CD4 T cell crosstalk to dictate the tumor immune response. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 4052. doi:10.1158/1538-7445.AM2015-4052

Effect of regular circus physical exercises on lymphocytes in overweight children.

Obesity associated with a sedentary lifestyle can lead to changes in the immune system balance resulting in the development of inflammatory diseases. The aim of this study was to compare lymphocyte activation mechanisms between overweight children practicing regular circus physical exercises with non-exercised children. The study comprised 60 pubescent children randomly divided into 4 groups: Overweight Children (OWC) (10.67 ± 0.22 years old), Overweight Exercised Children (OWE) (10.00 ± 0.41 years old), Eutrophic Children (EC) (11.00 ± 0.29 years old) and Eutrophic Exercised Children (EE) (10.60 ± 0.29 years old). OWE and EE groups practiced circus activities twice a week, for 4.3 ± 0.5 and 4.4 ± 0.5 months, respectively. Percentage of T regulatory cells (Treg) and the expression of CD95 and CD25 in CD4+ lymphocytes were evaluated by flow cytometry. Lymphocyte proliferation capacity was measured by [14C]-thymidine incorporation and mRNA expression of IL-35, TGF-beta, IL-2 and IL-10 by real-time PCR. Lymphocyte proliferation was higher in OWC and OWE groups compared with the EC (3509 ± 887; 2694 ± 560, and 1768 ± 208 cpm, respectively) and EE (2313 ± 111 cpm) groups. CD95 expression on lymphocytes was augmented in the EC (953.9 ± 101.2) and EE groups (736.7 ± 194.6) compared with the OWC (522.1 ± 125.2) and OWE groups (551.6 ± 144.5). CTLA-4 expression was also lower in the OWC and OWE groups compared with the EC and EE groups. Percentage of Treg, IL-35, and IL-10 mRNA expression were lower in the OWC and OWE groups compared with the EC and EE groups. In conclusion, overweight children present altered immune system balance characterized by elevated lymphocyte proliferation due to a decrease in T regulatory cell percentage. These effects were partially reverted by moderate physical exercise, as demonstrated by decreased lymphocyte proliferation.

Vitamin D as an adjunct to subcutaneous allergen immunotherapy in asthmatic children sensitized to house dust mite

We aimed to investigate the efficacy, safety, and T regulatory cell response of vitamin D as an adjunct to allergen-specific immunotherapy (IT). Fifty children with asthma and receiving pharmacotherapy were randomized into three groups as: subcutaneous IT (SCIT) along with vitamin D supplementation (650U/day; n: 17), SCIT alone (n: 15), and pharmacotherapy alone (n: 18). All patients were evaluated at baseline, 6th and 12th months for scorings of symptoms and medication, skin prick testing, total IgE, specific IgE, and Der p 1-specific IgG4. In addition, D.pteronyssinus-induced CD4(+) CD25(+) FOXP3(+) T regulatory cell percentage, intracellular Foxp3 expression, and peripheral blood mononuclear cell IL-10 and TGF-β responses were assessed. In the SCIT+vitamin D and SCIT alone groups, total asthma symptom score (TASS), total symptom score (TSS), and total medication scores (TMS) were significantly lower than pharmacotherapy group at the end of 1year. While the comparison of delta values (Δ 6th and Δ 12th month-baseline) of those scores revealed no significant differences between the two IT groups, TASS at the 6th month was lower in the SCIT+vitamin D group compared with others. There was a significant and positive trend in the levels of Der p 1-specific IgG4 in both IT groups throughout the study period. Whereas the levels of Der p 1-induced IL-10 and TGF-β were similar between IT groups, the mean fluorescence intensity of Foxp3 was highest in the SCIT+vitamin D group compared with others at the 12th month. The rate of discontinuation of inhaled corticosteroid (ICS) was 6/17 in SCIT+vitamin D, 3/15 in SCIT, and 0/18 in the pharmacotherapy group (P=0.02). Both SCIT groups fared better than pharmacotherapy alone at the end of 1year. Although the clinical and immunologic outcomes were mostly similar between the two IT groups, some favorable outcomes of vitamin D warrant further investigation in more selected populations with varying doses as adjunct to IT.

Quantitative analysis of regulatory T cells in kidney graft recipients: A relationship with calcineurin inhibitor level

Background Monitoring of immunosuppressive drug levels can prevent some adverse effects in patients with solid organ transplantation. However, the possible relationship between these drug levels and their biological effect on immune cells has not been studied in depth. The aim of this work was to assess the possible effect of immunosuppressive therapy with calcineurin inhibitors on the levels of regulatory T cells in patients with kidney transplantation. Methods Serial samples of peripheral blood were obtained from six patients that underwent kidney transplantation and received a triple pharmacological therapy, which included a calcineurin inhibitor (Cyclosporine A or Tacrolimus). Levels of CD4+CD25 high, CD4+Foxp3+ and CD8+CD28− cells and calcineurin inhibitors were evaluated by flow cytometry, and by radioimmunoassay, respectively. In addition, we assessed the in vitro effect of cyclosporine and tacrolimus on the number of T regulatory cells in peripheral blood mononuclear cells from healthy subjects. Results Diminished levels of total CD8+ T cells were found at week 1 after kidney transplantation, with a recovery of this subpopulation at week twelve. In addition, a significant decrease in CD8+CD28− T cell levels was observed at weeks 4 and 12 after transplantation. In contrast, no significant differences were observed in the levels and function of CD4+CD25 high or CD4+Foxp3+ regulatory T cells. Furthermore, no significant correlation between the level/dose ratios of calcineurin inhibitors and the percentages of regulatory cells was detected. On the other hand, in vitro assays showed that cyclosporine (5.0 ug/mL) and tacrolimus (100 ng/mL) diminished the percentages of CD8+CD28− cells, with no significant effect on natural T regulatory cells. Conclusions Our results suggest that although calcineurin inhibitors do not have a significant effect on the level and function of CD4+CD25 high or CD4+Foxp3+ regulatory T cells in patients with kidney transplantation, these drugs seem to exert a down-regulatory effect on CD8+CD28− lymphocytes.