Forkhead Box P3 Expression Research Articles

T-cell phenotypes in chronic rhinosinusitis with nasal polyps in Japanese patients

BackgroundChronic rhinosinusitis with nasal polyps is characterized by local inflammation and is categorized into two subtypes in Japan: eosinophilic chronic rhinosinusitis, and non-eosinophilic chronic rhinosinusitis. The objective of this study was to investigate the expression of key transcription factors for Treg and Th1/Th2/Th17 cells, in relation to the mRNA expression of representative cytokines in these two subtypes of chronic rhinosinusitis with nasal polyps.MethodsThe expression of forkhead box P3 (FOXP3), T-box transcription factor (T-bet), GATA3, retinoid acid-related orphan receptor C (RORc), the suppressive cytokines TGF-β1 and IL-10, and Th1/Th2/Th17 cytokines (IFN-γ, IL-4, IL-5, IL-13, IL-17) were analyzed by means of RT-PCR in eosinophilic polyps. Eosinophilic polyps were defined as having an eosinophil count of more than 50 per microscopic field (×400 magnification) using five fields located in the subepithelial area of the polyps, while the non-eosinophilic polyps and controls did not fulfill this criteria. The numbers of T cells, CD4+ T cells, CD8+ T cells and Treg were histologically counted using sections that were immunostained for CD3, CD4, CD8, and FOXP3, respectively.ResultsIn eosinophilic polyps, we observed significantly fewer CD4+ T cells and CD8+ T cells, and lower GATA3, RORc and IL-10 mRNA expression, but a significantly higher IL-5, and IL-13 mRNA expression compared with controls, whereas FOXP3 and T-bet mRNA expression were not significantly different compared with controls. In non-eosinophilic polyps, FOXP3, IL-10, IL-17A, TGFβ1 and IFNγ mRNA expression was significantly higher compared with controls, whereas IL-4, 5 and 13 expression was not significantly different from controls.ConclusionWe showed a reduction of GATA3 and RORc mRNA, low Treg-related cytokines and elevated Th2 cytokine levels in eosinophilic chronic rhinosinusitis, whereas we demonstrated the upregulation of Treg cells and increases of Th1 and Th17 cytokines in non-eosinophilic chronic rhinosinusitis in the Japanese population. The different mRNA expression profiles of Treg and Th1/Th2/Th17 signature transcription factors and cytokines between eosinophilic chronic rhinosinusitis and non-eosinophilic chronic rhinosinusitis suggests heterogeneity in the pathogenesis of chronic rhinosinusitis with nasal polyps.

Increased Intraepithelial Vα24 Invariant NKT Cells in the Celiac Duodenum.

Celiac Disease (CD) is an interferon (IFN)γ-mediated duodenal hypersensitivity to wheat gluten occurring in genetically predisposed individuals. Gluten-free diet (GFD) leads to a complete remission of the disease. Vα24-restricted invariant NKT (iNKT) cells are important to maintain immune homeostasis in the gut mucosa because of their unique capacity to rapidly produce large quantities of both T-helper (Th)1 and Th2 cytokines upon stimulation. We studied the presence of these cells in the CD duodenum. Duodenal biopsies were obtained from 45 untreated-CD patients (uCD), 15 Gluten Free Diet-CD patients (GFD-CD), 44 non-inflamed non-CD controls (C-controls) and 15 inflamed non-CD controls (I-controls). Two populations from Spain and Argentina were recruited. Messenger RNA (mRNA) expression of Vα24-Jα18 (invariant TCRα chain of human iNKT cells), IFNγ and intracellular transcription factor Forkhead Box P3 (Foxp3), and flow cytometry intraepithelial lymphocyte (IEL) profile were determined. Both uCD and GFD-CD patients had higher Vα24-Jα18 mRNA levels than non-CD controls (I and C-controls). The expression of Vα24-Jα18 correlated with Marsh score for the severity of mucosal lesion and also with increased mRNA IFNγ levels. uCD and GFD-CD patients had decreased mRNA expression of FoxP3 but increased expression of Vα24-Jα18, which revealed a CD-like molecular profile. Increased numbers of iNKT cells were confirmed by flow cytometry within the intraepithelial lymphocyte compartment of uCD and GFD-CD patients and correlated with Vα24-Jα18 mRNA expression. In conclusion, we have found an increased number of iNKT cells in the duodenum from both uCD and GFD-CD patients, irrespective of the mucosal status. A CD-like molecular profile, defined by an increased mRNA expression of Vα24-Jα18 together with a decreased expression of FoxP3, may represent a pro-inflammatory signature of the CD duodenum.

MicroRNA-33-dependent regulation of macrophage metabolism directs immune cell polarization in atherosclerosis.

Cellular metabolism is increasingly recognized as a controller of immune cell fate and function. MicroRNA-33 (miR-33) regulates cellular lipid metabolism and represses genes involved in cholesterol efflux, HDL biogenesis, and fatty acid oxidation. Here, we determined that miR-33-mediated disruption of the balance of aerobic glycolysis and mitochondrial oxidative phosphorylation instructs macrophage inflammatory polarization and shapes innate and adaptive immune responses. Macrophage-specific Mir33 deletion increased oxidative respiration, enhanced spare respiratory capacity, and induced an M2 macrophage polarization-associated gene profile. Furthermore, miR-33-mediated M2 polarization required miR-33 targeting of the energy sensor AMP-activated protein kinase (AMPK), but not cholesterol efflux. Notably, miR-33 inhibition increased macrophage expression of the retinoic acid-producing enzyme aldehyde dehydrogenase family 1, subfamily A2 (ALDH1A2) and retinal dehydrogenase activity both in vitro and in a mouse model. Consistent with the ability of retinoic acid to foster inducible Tregs, miR-33-depleted macrophages had an enhanced capacity to induce forkhead box P3 (FOXP3) expression in naive CD4(+) T cells. Finally, treatment of hypercholesterolemic mice with miR-33 inhibitors for 8 weeks resulted in accumulation of inflammation-suppressing M2 macrophages and FOXP3(+) Tregs in plaques and reduced atherosclerosis progression. Collectively, these results reveal that miR-33 regulates macrophage inflammation and demonstrate that miR-33 antagonism is atheroprotective, in part, by reducing plaque inflammation by promoting M2 macrophage polarization and Treg induction.

Radix Saposhnikovia extract suppresses mouse allergic contact dermatitis by regulating dendritic-cell-activated Th1 cells

BackgroundRadix Saposhnikovia (RS), called “Fangfeng” in China, is commonly used in Chinese medicinal formulae to treat allergic and inflammatory diseases. However, the underlying mechanisms of RS in ameliorating allergy remain unknown. PurposeTo study the effects of RS extract on allergic contact dermatitis (ACD) in a mouse model and to investigate the underlying mechanisms in vivo and ex vivo. MethodsACD was induced by sensitizing the mice and treating an ear auricle with 1-chloro-2,4-dinitrobenzene (DNCB). RS extract was administered during the sensitization and/or elicitation phase. Ear swelling was noted and lymphocytic infiltration was investigated with hematoxylin and eosin staining. The cytokines in the sera and the supernatants of lymphocyte cultures were determined with enzyme-linked immunosorbent assays. Lymphocyte proliferation was assessed with a 3-(4,5)-dimethylthiazol-2-y1)-2,5-diphenyltetrazolium bromide (MTT) assay. The maturation of dendritic cells (DCs) and the differentiation of T cells were examined with flow cytometry. The mRNA expression of T-bet, GATA-3, and forkhead box p3 (Foxp3) was evaluated with real-time PCR. ResultsRS extract (1.3 or 2.6 g/kg) markedly reduced the ear swelling and the intense cellular infiltration of inflammatory cells in the ear tissue. The ratio of interferon γ (IFN-γ)/interleukin 4 (IL-4) was reduced in the sera of the DNCB-sensitized mice and the lymphocyte culture supernatants after treatment with the extract. Further study of the initial stage of ACD revealed that RS extract prevented the differentiation of naïve T cells into Th1 cells, reduced the proportion of CD3+CD4+ (Th) cells, and suppressed the secretion of IFN-γ and the expression of T-bet mRNA in lymphocytes. The RS extract also reduced the proportion of DCs in the sensitized mouse lymphocytes and the expression of CD40+CD86+ cells in the DCs. ConclusionRS extract is effective in treating ACD because it regulates the development of DCs and DC-activated Th1 differentiation.

The Prognostic Value of Forkhead Box P3 Expression in Operable Breast Cancer: A Large-Scale Meta-Analysis.

BackgroundRecent studies have shown that the forkhead box P3 (FOXP3) protein has a prognostic role in breast cancer. However, these results are controversial. Therefore, the aim of this meta-analysis was to clarify the prognostic role of FOXP3 expression in operable breast cancer cases.MethodsEligible studies describing the use of FOXP3 as a prognostic factor for operable breast cancer cases were identified. Clinicopathological features, disease-free survival (DFS), and overall survival (OS) data were collected from these studies and were analyzed using Stata software.ResultsA total of 16 articles containing data from 13,217 breast cancer patients met the inclusion criteria established for this study. The subsequent meta-analysis that was performed showed that high levels of FOXP3 are not significantly associated with DFS and OS with significant heterogeneity. An additional subgroup analysis demonstrated that intratumoral FOXP3+ regulatory T cells (Tregs) were positively correlated with adverse clinicopathological parameters, yet they did not show an association with DFS or OS. For tumor cells, the pooled results revealed that FOXP3 is significantly associated with DFS (HR: 2.55, 95% CI: 1.23–5.30) but is not associated with clinicopathological parameters or OS. We also observed a significant correlation between FOXP3 expression and survival in the estrogen receptor-positive (ER)+ subgroup (HR: 1.83, 95% CI: 1.36–2.47 for DFS, HR: 1.87, 95% CI 1.28–2.73 for OS), in the Asian region (HR: 1.98, 95% CI: 1.56–2.50 for DFS, HR: 1.93, 95% CI: 1.12–3.35 for OS) and using the median as the FOXP3-positive cut-off value (HR: 1.94, 95% CI: 1.57–2.39 for DFS, HR: 2.06; 95% CI: 1.36–3.11 for OS).ConclusionThis meta-analysis indicates that a prognostic role for FOXP3 expression in operable breast cancer cases depends on the FOXP3-positive region, ER status, geographic region and the FOXP3-positive cut-off value.

FoxP3 in papillary thyroid carcinoma induces NIS repression through activation of the TGF-β1/Smad signaling pathway.

Forkhead box P3 (FoxP3) expression in papillary thyroid carcinoma (PTC) is associated with resistance to radioiodine treatment. The sodium iodine symporter (NIS) is a plasma membrane glycoprotein, the repression of which may render the tumor refractive to radioiodine therapy. In this study, samples from 90 PTCs as well as 40 normal thyroid tissues were examined for FoxP3 and NIS by immunohistochemistry and real-time PCR. We found that FoxP3 was associated with decreased NIS expression. Lentiviral-mediated FoxP3-overexpressing cells were constructed and real-time PCR and western blotting were performed to evaluate the expression of NIS. Meanwhile, key members of the transforming growth factor-β1 (TGF-β1) pathway were explored by ELISA and immunofluorescence and a neutralizing TGF-β1 antibody was used to block activity. In vitro, FoxP3 overexpression significantly reduced NIS transcript and protein levels and the TGF-β1 pathway was activated. However, treatment with neutralizing TGF-β1 antibody partially abrogated FoxP3-induced NIS repression. These findings suggest that FoxP3 could compromise NIS expression by inducing TGF-β1.

597. AAV. NT-3 Treatment Attenuates Spontaneous Autoimmune Peripheral Polyneuropathy

The spontaneous autoimmune peripheral polyneuropathy (SAPP) model in B7-2 knockout non-obese diabetic (NOD) mice demonstrates overlapping clinical features with chronic inflammatory demyelinating polyradiculoneuropathy (CIDP). Secondary axonal loss is prominent in the progressive phase of this neuropathy. Neurotrophin 3 (NT-3) is an important autocrine factor supporting Schwann cell (SC) survival and differentiation and stimulates neurite outgrowth and myelination. Recently, NT-3 delivered in bone marrow-derived neural stem cells was shown to exert therapeutic effect, by reducing the inflammation and accelerating remyelination in experimental encephalomyelitis (EAE), an animal model of multiple sclerosis. These findings led to considerations of AAV.NT-3 gene therapy via intramuscular delivery into SAPP mice to attenuate the disease. The results show AAV.NT-3 injection into gastrocnemius muscle of 25 week old SAPP mice produced measurable NT-3 levels in the serum at 7 weeks post gene delivery, sufficient to protect sciatic nerve motor function and compound muscle action potentials (CMAPs). Sciatic nerves of mice, receiving gene transfer had a significantly greater number of remyelinated fibers and decreased infiltration of CD3+ T cells compared to controls. These data correlated with reduced expression of the pro-inflammatory cytokines, interleukin-1β (IL-1β) and tumor necrosis factor (Tnf-α) and increased expression of anti-inflammatory markers, interleukin-10 and forkhead box-P3 (Foxp3) in the sciatic nerve. The treatment also increased the percentage of CD4+CD25+Foxp3+ regulatory T cells (Tregs) in the spleen. This proof-of-principle study established a therapeutic benefit by neuroprotective and immunomodulatory effects of AAV-NT-3 treatment in SAPP. This study demonstrates the potential clinical translational path for AAV delivered NT-3 for refractory cases of CIDP..

All-trans retinoic acid favors the development and function of regulatory T cells from liver transplant patients

Graft-versus-host disease (GVHD) is an intractable complication in transplant patients. Regulatory T cells (Tregs) have the ability to prevent GVHD and consist of two subsets: natural Tregs (nTregs) and induced Tregs (iTregs). In comparison to nTregs, iTregs originate in the periphery under certain conditions and show improved proliferative and suppressive abilities in an inflammatory milieu. All-trans retinoic acid (atRA) favors Treg expansion and FoxP3 expression in human Tregs. However, whether atRA can affect the function of iTregs from transplant patients remains inconclusive. Therefore, we sorted naïve T cells from liver transplant patients and cultured them in vitro. Further analyses were performed to assess the suppressive function of iTregs in vitro and in vivo. atRA favored expansion and forkhead box P3 expression in iTregs from transplant patients. In comparison to iTregs from healthy donors, iTregs from transplant patients showed decent suppressive abilities in vitro and in vivo. Our findings suggest that atRA can potentially improve the development and function of iTregs from transplant patients. Furthermore, our results provide novel insights into Treg therapy in GVHD clinical trials.

Effect of Cell Density and HLA-DR Incompatibility on T-Cell Proliferation and Forkhead Box P3 Expression in Human Mixed Lymphocyte Reaction

BackgroundThe proliferation rates of human T cells in vitro are affected by some factors such as initial T-cell number, dose of stimulating cells, and duration of culture. The transcription factor forkhead box P3 (FoxP3) has been used to identify regulatory T cells in humans and is thought to correlate with tolerance to allogeneic organ transplant. Thus, it is important to optimize conditions to expand FoxP3 cell proliferation to improve engraftment of allogeneic organ transplants. MethodsWe studied proliferative responses and FoxP3 expression in divided T cells with the use of flow cytometric analysis of Ki-67 in culture of different concentrations of responding cells (6 × 106, 4 × 106, 2 × 106, 1 × 106, and 0.5 × 106cells/mL), different types of stimulating cells (lymphocytes and low density cells), and different numbers of HLA mismatches. ResultsThe proportion of CD3(+) cells, CD4(+)CD25(+) cells, and CD4(+)CD25(+)FoxP3(+) cells among mononuclear cells were highest at initial cell concentration of 2 × 106 responder cells/mL with lymphocytes as stimulators at day-5 mixed lymphocyte reaction (MLR). They were highest at a concentration of 4 × 106 responder cells/mL with low density cells as stimulators. The recovery (%), proportion of CD3(+) cells, CD4(+)CD25(+) cells, and CD4(+)CD25(+)FoxP3(+) cells with 2 HLA-DR incompatibility were significantly higher than those of 1 HLA-DR incompatibility at day-5 MLR. ConclusionsInitial cell concentration and HLA-DR incompatibility can affect the generation of FoxP3+ T cells in human MLR. These factors could be considered for efficient generation of Tregs for clinical trials in the future.

Expression and function of forkhead box P3 in the tissue of rat gastric cancer model

Objective To study the expression and function of forkhead box P3(Foxp3)in the tissue of rat gastric cancer model. Methods Forty- six Wister rats were divided into two groups: group A(n= 23)given sarcosine ethyl ester hydrochloride and sodium nitrite carcinogen for 6 months to establish the rat gastric cancer model,and group B(n= 23)as the normal control group.The reverse transcriptase- polymerase chain reaction(RT- PCR), Western blotting,and immunohistochemistry were used to detect the expression and location of Foxp3 in the gastric tissues.Immunohistochemistry was used to detect the expression and localization of Foxp3 in gastric cancer tissues.The relationship between the expression of Foxp3 and gastric lesions was statistically analyzed. Results The expression of Foxp3 mRNA in the gastric tissue of group A existed to varying degrees, and increased with the grades, and there was no Foxp3 mRNA expression in the gastric tissues of group B.Immunohistochemistry revealed that the expression of Foxp3 protein was mainly distributed in the nuclei of gastric cancer cells.In 16 gastric cancer sections,4 cases of precancerous lesions,and 3 cases of proliferative lesions in group A, 10(62.50%), 2(50.00%) and 1 case(33.30%) was positive for the Foxp3 protein, respectively.In group B, no Foxp3 protein staining was detected all 23 cases.Statistical analysis showed a linear correlation of Foxp3 protein expression in gastric tissue and lesion classification(r= 4.26, P< 0.01). Conclusion The expression of Foxp3 universally exists in gastric cancer cells and tissues, suggesting Foxp3 may play important roles in the occurrence and development of gastric cancer. Key words: Gastric carcinoma; Forkhead/winged helix transcription factor P3

FOXP3 expression in tumor cells and its role in cancer progression

Forkhead box P3 (FOXP3), a gene member of the forkhead/winged-helix family of transcription regulators, is implicated in regulating immune system development and function. This gene has been found to be of crucial importance for the generation of CD4CD25 regulatory T cells (Tregs). In addition to its expression in the lymphocyte lineage, studies have recently described FOXP3 expression in normal and cancer cells nonhematopoietic-derived, suggesting that FOXP3 exerts a broader function than that on Tregs. A role for FOXP3 as an onco-suppressor gene in human cancers has been suggested based on in vitro studies showing that FOXP3 is implicated in repressing various oncogenes and enhancing expression of tumorsuppressor genes. However, numerous studies in samples from human cancer patients showed a positive correlation between FOXP3 expression and poor prognosis, especially with metastasis. Further investigations are required to clarify the significance of FOXP3 expression in tumor cells and to identify the mechanisms by which it affects prognosis.

MicroRNA-21 Negatively Regulates Treg Cells Through a TGF-β1/Smad-Independent Pathway in Patients with Coronary Heart Disease

Background: CD4+CD25+FoxP3+ regulatory T cells (Treg cells) play a protective role against the development and progression of the inflammatory disease atherosclerosis (AS). MicroRNA-21 (miR-21) is expressed in Treg cells and is up-regulated in the context of AS and other inflammatory diseases. Aims: This study aimed to determine the role of miR-21 in Treg cell regulation and gene expression during the development of AS in patients with coronary heart disease (CHD). Methods and Results: MiR-21 expression in peripheral blood mononuclear cells (PBMCs) was significantly up-regulated in patients with CHD (acute myocardial infarction (AMI) group, n=24; unstable angina (UA) group, n=21; stable angina (SA) group, n=24) compared with patients with chest pain syndrome (CPS, n=27), and miR-21 expression showed an increasing trend from SA to UA to AMI patients. Moreover, flow cytometry analysis indicated that the frequencies of circulating Treg cells decreased in a manner proportionate opposite with the level of miR-21. Quantitative real-time PCR (qRT-PCR) revealed a decrease in mRNA expression of forkhead box P3 (foxp3), transforming cell growth factor beta 1(TGF-β1) and smad7 (a known target gene of miR-21). ELISA analysis revealed a decrease in TGF-β1 secreted into the plasma. In addition, we transfected PBMCs with a miRNA negative control (NS-m), a miR-21 mimic (miR-21-m), a miRNA inhibitor negative control (NS-i), or a miR-21 inhibitor(miR-21-i). Up-regulation of miR-21 decreased the frequency of circulating Treg cells, decreased the expression levels of foxp3, TGF-β1 and smad7, and decreased the amount of TGF-β1 secreted into the plasma. Consistent with these observations, miR-21 down-regulation increased the frequency of circulating Treg cells, increased the expression of foxp3, TGF-β1 and smad7, and increased the amount of TGF-β1 secreted into the plasma. Conclusions: Because the smad7 expression pattern was similar to that of TGF-β, our study suggests that miR-21 can negatively regulate the frequency of circulating Treg cells through a TGF-β1/smad-independent signaling pathway in PBMCs.

Application of Minicircle Technology of Self-Reproducing Synthetic Protein Drugs in Preventing Skin Allograft Rejection.

Recently, it has been reported that minicircle vectors could allow the expression of transgenes using the protein synthesis system of the host. Here, we tested a novel strategy to permit the production of synthetic biologics using minicircle technology and evaluated their feasibility as a therapeutic tool in a skin allograft model. We engineered vectors to carry cassette sequences for tocilizumab [anti-soluble interleukin-6 receptor (sIL-6R) antibody] and/or etanercept [tumor necrosis factor receptor 2 (TNFR2)-Fc fusion protein], and then isolated minicircle vectors from the parent vectors. We verified the production of proteins from minicircles and their duration in HEK293T cells and mice. We also evaluated whether these proteins were expressed at levels sufficient to ameliorate skin allograft rejection in mice. Each minicircle transfected into cells was detectable for at least 30 days. In mice, the drugs were mainly expressed in the liver and were detectable for at least 10 days after a single injection. These drugs were also detected in the blood. Treatment of mice with minicircles prolonged skin allograft survival, which was accompanied by a reduction of the number of interferon-γ+ or interleukin-17+ lymphocytes and an induction of forkhead box P3 expression. These findings suggest that blocking of sIL-6R and/or TNF-α using minicircles encoding tocilizumab and/or etanercept was functionally active and relevant for preventing acute allograft rejection. Self-reproducing synthetic protein drugs produced using minicircle technology are potentially powerful tools for preventing acute rejection in transplantation.

Regulatory T cells in systemic lupus erythematosus

Autoantibodies are associated with various autoimmune diseases. Systemic lupus erythematosus (SLE) is an autoantibody-associated autoimmune disease which affects multiple organs. Although both genetic and environmental factors are implicated in lupus pathogenesis, the etiology of the disease remains elusive. The discovery of CD4(+)CD25(+) regulatory T cells (Tregs) that characteristically express forkhead box p3 (Foxp3) gene have greatly advanced our understanding of immune systems in autoimmune diseases. CD4(+) Tregs can be classified into two main populations: thymus-derived naturally occurring Tregs (nTregs) and induced Tregs (iTregs) generated from CD4(+)CD25(-) precursors in the periphery. Recently, accumulating evidence suggests that these Tregs play important roles in the regulation of humoral immune responses. In this review, we discuss recent findings on the role of Tregs in SLE.

Regulatory T Cells in Human Cord Blood of Preterm and Term Infants

Regulatory T (Treg) cells are a subset of CD4+ T cells that play key roles in the maintenance of immunologic self-tolerance and negative control of immune responses. Treg cells are defined based on expression of CD4, CD25, and transcription factor forkhead box P3 (FoxP3). FoxP3 controls the development and function of Treg cells and can be used as a reliable marker of Treg cells, however, its intracellular localization prohibits its use for the isolation of viable Treg cells. Most FoxP3+ Treg cells express low levels of CD127 in adult peripheral blood, however, the expression of CD127 in cord blood (CB) Treg cells of preterm and term infants at each gestational age remains unknown. Being that CD127 is a cell surface marker, it enables the isolation of viable Treg cells by flow cytometric sorting for further analysis. We analyzed CD4+CD25+FoxP3+ and CD4+CD25+CD127− T cells in preterm and term CB at various gestational ages.CB samples were obtained at Iwate Medical University hospital from preterm and term neonates who had no hereditary disorders, hematologic abnormalities, or immunodeficiency diseases. Of 103 total samples, 36 were obtained from preterm (24–36 gestational weeks) neonates and 67 were obtained from term (37–41 gestational weeks) neonates. Out of 36 preterm infants, 9 were diagnosed with chorioamnionitis histologically. None of the mothers involved in the study had any specific underlying diseases. CB mononuclear cells were isolated and analyzed by FACSCalibur flow cytometer and CellQuestPro software (BD Biosciences).No differences were observed in the proportions of CD25+FoxP3+ (median 4.5%) and CD25+CD127− (median 5.0%) cells in the CD4+ T-cell population. A strong correlation was found between the proportions of CD25+FoxP3+ and CD25+CD127− cells in the CD4+ T-cell population (r=0.96). The proportion of CD25+FoxP3+ cells in the CD4+ T-cell population in the CB of neonates at 24-26, 27-29, and 30-32 gestational weeks was significantly higher than in the CB of neonates at 37-38 and 39-41 gestational weeks. The proportion of CD25+CD127− cells in the CD4+ T-cell population in the CB of neonates at 24-26, 27-29, and 30-32 gestational weeks was also higher than in the CB of neonates at 37-38 and 39-41 gestational weeks. The absolute number of both CD4+CD25+FoxP3+ and CD4+CD25+CD127− T cells did not differ between the CB of preterm and term neonates. Absolute lymphocyte counts in preterm CB were significantly lower than term infants (P<0.05). The proportions of CD25+FoxP3+ and CD25+CD127− cells in the CD4+ T-cell population did not differ between preterm infants with histological chorioamnionitis (n=9) and no histological chorioamnionitis (n=27).We showed that CD127 is preferable to FoxP3 as a marker for identifying Treg cells in CB of various gestational ages and would be useful for separating Treg cells by flow cytometry for therapeutic applications. The proportions of Treg cells in the CB of preterm infants were significantly higher than in the CB of term infants. The high Treg proportion during early gestation suggests that fetal naive T cells have a high propensity to differentiate into Treg cells in response to antigenic stimulation, such as by maternal alloantigens. The functional implications of the high proportion of Treg cells in preterm CB are unknown but may be important for the suppression of undesirable alloimmune reactions to maternal derivatives in utero and the maintenance of tolerance during pregnancy. DisclosuresNo relevant conflicts of interest to declare.

Expression of Forkhead box P3 isoforms in hepatocellular carcinoma cells

Meeting abstracts Forkhead box P3 (FOXP3) is well known as a key regulator of immune homeostasis. The abnormal expression of FOXP3 can contribute to features of several cancers including metastasis and invasion, and it has also been associated with prognosis of some cancers. However, little

Function of interleukin-17 and -35 in the blood of patients with hepatitis B-related liver cirrhosis.

Intrahepatic T helper (Th)17 cytokine and serum interleukin (IL)-17 levels in patients with hepatitis B are positively correlated with the progression of liver cirrhosis (LC). IL-35 can significantly inhibit the differentiation of Th17 cells and the synthesis of IL-17. The present study aimed to investigate the function and expression of IL-17 and IL-35 in the blood of patients with hepatitis B-related LC. The levels of IL-17 and IL-35 in the peripheral blood of 30 patients with chronic hepatitis B (CHB), 79 with LC, 14 with chronic severe hepatitis B (CSHB), and 20 normal controls were detected by ELISA. Quantitative polymerase chain reaction was used to evaluate Epstein-Barr virus-induced gene 3 (EBI3), forkhead box (FOX)P3 and IL-17 mRNA expression levels in peripheral blood mononuclear cells (PBMCs). Western blotting was used to determine protein expression. The liver function of patients and normal controls was measured. EBI3, IL-17 and FOXP3 mRNA expression levels in PBMCs from patients with LC, CHB and CSHB were higher than those in cells from the controls. IL-17 mRNA levels differed significantly according to the Child-Pugh classification and exhibited an upward trend over time in contrast to a downward trend for EBI3 and FOXP3 mRNA. The changes in protein expression in the peripheral blood were consistent with the changes in mRNA expression. Serum IL-17 levels were positively correlated with total bilirubin (TBIL), alanine aminotransferase (ALT) and Child-Pugh grade, and were negatively correlated with albumin. These observed differences were significant. Serum IL-35 levels were negatively correlated with albumin, but not with Child-Pugh grade, ALT and TBIL. IL-17 and IL-35 may be critically involved in the pathogenesis of hepatitis B-related LC.

Tamibarotene modulates the local immune response in experimental periodontitis.

Tamibarotene (Am80), a synthetic retinoic acid receptor (RAR), is an agonist with high specificity for RARα and RARβ. Retinoid agonists have been shown to inhibit Th17 cell polarization and to enhance forkhead box P3 (Foxp3) expression during the course of inflammatory diseases. The aim of this study was to evaluate the previously unrecognized role of Am80 in regulating the immune responses of periodontitis within the oral microenvironment. The experimental model of periodontitis in mice was induced by oral infection with Porphyromonas gingivalis (P. gingivalis) W83. Our results indicated that Am80 effectively suppressed alveolar bone resorption induced by P. gingivalis W83 and decreased the number of osteoclasts. We clarified that these effects were closely associated with the reduced percentage of CD4(+) retinoid-related orphan receptor (ROR)γt(+) cells and increased the percentage of CD4(+) Foxp3(+) cells in the gingival tissues, cervical lymph nodes (CLNs), and spleen. Furthermore, in P. gingivalis-infected mice, Am80 down-regulated mRNA expression levels of interleukin-17A (IL-17A), receptor activator of nuclear factor-kappa beta ligand (RANKL), monocyte chemotactic protein-1 (MCP-1), IL-6, and IL-1β. Simultaneously, Am80 up-regulated expression levels of IL-10 and transforming growth factor-β1 (TGF-β1) in gingival tissues and the CLNs. Our results suggest that Am80 could protect against periodontal bone resorption, primarily through the modulation of immune responses in the oral microenvironment, and demonstrate the potential of Am80 as a novel clinical strategy for preventing periodontitis.

Abstract 5207: miR-491 and miR-218: Two possible tools to reduce FOXP3 expression in breast carcinomas

Abstract The Forkhead box P3 (FOXP3) gene is a member of the forkhead/winged-helix family of transcription factors implicated in the regulation of immune system development and function. However, FOXP3 is also expressed in human epithelial cancers, where it has been reported to be associated with poor prognosis and in particular with metastasis. Aim of our work is to identify microRNAs able to regulate FOXP3 expression in breast tumors. To discover microRNAs able to regulate FOXP3 expression in breast cancer cells, an in silico analysis has been performed. Among microRNAs harboring FOXP3 seed regions, we focused our attention on miR-218 and miR-491, described to have oncosuppressive properties. Indeed, it has been reported that miR-218 expression stimulates activation of tumor suppressor genes and miR-491 expression inversely correlates with migratory potential in HCC cell lines and in vivo with metastatic potential. We therefore evaluated the ability of these microRNAs to act as oncosuppressors by targeting FOXP3 in a breast cancer model. After transient co-transfection either of miR-218 or miR-491 with FOXP3 in MDA-MB-231 cells, a significant decrease in FOXP3 expression at protein level by WB was found. To perform functional studies both in vitro and in vivo, we generated a breast cancer cell model by stable transfection of MDA-MB-231 with inducible Tet-off plasmid encoding for FOXP3 encompassing 3′UTR region, thus maintaining microRNA-mediated regulation. We demonstrated that FOXP3 expressing clones display an increased migration capacity as compared with their respective non-induced cells. Also in these stable clones a reduction of FOXP3 expression after transfection of miR-491 and miR-218 has been demonstrated by WB. Moreover, FOXP3 was confirmed to be a direct target of both microRNAs by luciferase reporter assay. We also found an inverse correlation between miR-491 levels and FOXP3 expression in human breast carcinoma specimens. Overall, these preliminary results demonstrate that microRNAs can regulate FOXP3 expression, and encourage to further investigate the biological and functional consequences of this targeting, and to exploit microRNAs as a potential therapeutic tool for FOXP3 expressing breast carcinomas. Citation Format: Martina Di Modica, Tiziana Triulzi, Viola Regondi, Marilena V. Iorio, Andrea Balsari, Elda Tagliabue, Patrizia Casalini. miR-491 and miR-218: Two possible tools to reduce FOXP3 expression in breast carcinomas. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 5207. doi:10.1158/1538-7445.AM2014-5207

Heme Oxygenase-1 Ameliorates Dextran Sulfate Sodium-induced Acute Murine Colitis by Regulating Th17/Treg Cell Balance

Inflammatory bowel disease (IBD), including ulcerative colitis and Crohn's disease, is a group of autoimmune diseases characterized by nonspecific inflammation in the gastrointestinal tract. Recent investigations suggest that activation of Th17 cells and/or deficiency of regulatory T cells (Treg) is involved in the pathogenesis of IBD. Heme oxygenase (HO)-1 is a protein with a wide range of anti-inflammatory and immune regulatory function, which exerts significantly protective roles in various T cell-mediated diseases. In this study, we aim to explore the immunological regulation of HO-1 in the dextran sulfate sodium-induced model of experimental murine colitis. BALB/c mice were administered 4% dextran sulfate sodium orally; some mice were intraperitoneally pretreated with HO-1 inducer hemin or HO-1 inhibitor stannum protoporphyrin IX. The results show that hemin enhances the colonic expression of HO-1 and significantly ameliorates the symptoms of colitis with improved histological changes, accompanied by a decreased proportion of Th17 cells and increased number of Tregs in mesenteric lymph node and spleen. Moreover, induction of HO-1 down-regulates retinoic acid-related orphan receptor γt expression and IL-17A levels, while promoting Treg-related forkhead box p3 (Foxp3) expression and IL-10 levels in colon. Further study in vitro revealed that up-regulated HO-1 switched the naive T cells to Tregs when cultured under a Th17-inducing environment, which involved in IL-6R blockade. Therefore, HO-1 may exhibit anti-inflammatory activity in the murine model of acute experimental colitis via regulating the balance between Th17 and Treg cells, thus providing a possible novel therapeutic target in IBD.