The reduction of MHC II and CD40 was particularly evident on myel

The reduction of MHC II and CD40 was particularly evident on myeloid APCs (Fig. 3A). Besides the composition

of co-stimulatory molecules, T-cell differentiation is primarily determined by the cytokine milieu present at the time of initial activation [10]. Therefore, 2- or 8-week-old splenocytes were evaluated for cytokine production upon stimulation with increasing concentrations of LPS. As shown in Figure 3C, 2-week-old splenocytes produced significantly lower amounts of the proinflammatory cytokines TNF, IL-23, IL-6, and IL-12, while the PFT�� release of anti-inflammatory IL-10 was enhanced. The data acquired to this point suggested that the inability to generate an encephalitogenic T-cell response and to induce

CNS autoimmune disease could refer to the immature phenotype of APCs in younger mice with an insufficient expression of MHC II as well as to a higher frequency of phenotypes with regulatory and/or suppressive properties. To elucidate this possibility functionally, we co-cultured APCs and purified T cells obtained from 2- or 8-week-old mice in the presence of Ag in a crossover selleck kinase inhibitor design [19]. Splenic APCs were obtained from WT C57BL/6 mice, whereas T cells were isolated from MOG p35–55 T-cell receptor Tg mice. As indicated in Figure 4A, myelin-reactive T cells proliferated irrespective of their own age when activated by APCs Glutamate dehydrogenase obtained from 8-week-old mice. Two-week-old APCs failed to induce proliferation of both 2- and 8-week-old myelin-reactive T cells. Along the same lines, only 8-week-old, but not 2-week-old APCs promoted development of Th17 cells, while release of IFN-γ was only reduced when APCs were 8 weeks and T cells 2 weeks old (Fig. 4B). Based on the observation that certain phenotypes of APCs, such as plasmacytoid DC are capable of promoting development of anti-inflammatory T-cell phenotypes instead [20], we expanded our investigations to generation of Th2 cells and CD4+CD25+FoxP3+ Treg cells. As indicated in Figure 4B and

C, 2-week-old APCs in contact with 2-week-old T cells promoted development of Th2 cells and Treg cells as evaluated by release of IL-4, IL-10, or expression of FoxP3, respectively. In conjunction with the observation that T-cell differentiation upon direct, APC-independent activation of T cells did not markedly differ between 2- or 8-week-old mice (Fig. 2B and Supporting Information Fig. 1), these data corroborate that the age of the APC rather than the age of the corresponding T cell determines development of encephalitogenic T cells. In order to further elaborate the association between MHC II upregulation, APC maturation, and age, we investigated the expression of MHC II mRNA starting in newborn mice over the period of 8 weeks.

A new dimension of functional genomics has been introduced by nex

A new dimension of functional genomics has been introduced by next-generation sequencing technologies. R788 The high-depth sequencing achievable by such methods as RNA sequencing (RNA-seq) will enhance transcriptome

profiling and gene identification. Proteomic studies have been essential for validating gene annotations in Toxoplasma and for better characterizing proteins from distinct subproteomes. While significant effort has gone towards studying tachyzoite proteins, proteomic data for other developmental stages such as the bradyzoite and the sporozoite are notably lacking. Future proteomic studies directed at these life stages should provide a basis for better understanding the functional differences between them. Beyond simply cataloguing parasite proteins, proteomic studies should be able to begin complementing transcription analyses to better define the timing of protein expression during development. “
“Progress in our understanding of the role of the maternal immune system during healthy pregnancy will help us better understand the role of the immune system in adverse pregnancy outcomes. In this review, we discuss our present understanding of the ‘immunity of pregnancy’ in the context of the response to cervical and placental infections and how these responses affect both the mother and the fetus. We discuss novel Atezolizumab research buy and challenging concepts that help explain the immunological aspects of pregnancy and how

the mother and fetus respond to infection. “
“Interleukin 17A IL-17A is a crucial immunomodulator in various chronic immunological diseases including rheumatoid arthritis and inflammatory bowel disease. Adenylyl cyclase The cytokine has also been demonstrated to control the pathogenesis of the Mycobacterium tuberculosis by dysregulating production of cytokines and chemokines and promoting granuloma formation. Whether IL-17A regulates innate defence mechanisms of macrophages in response to mycobacterial infection remains to be elucidated. In the current

report, we investigated the effects of IL-17A on modulating the intracellular survival of Mycobacterium bovis bacillus Calmette–Guérin (BCG) in RAW264.7 murine macrophages. We observed that IL-17A pre-treatment for 24 hr was able to synergistically enhance BCG-induced nitric oxide (NO) production and inducible nitric oxide synthase expression in dose- and time-dependent manners. We further delineated the mechanisms involved in this synergistic reaction. IL-17A was found to specifically enhanced BCG-induced phosphorylation of Jun N-terminal kinase (JNK), but not of extracellular signal-regulated kinase 1/2 and p38 mitogen-activated protein kinase. By using a specific JNK inhibitor (SP600125), we found that the production of NO in BCG-infected macrophages was significantly suppressed. Taken together, we confirmed the involvement of the JNK pathway in IL-17A-enhanced NO production in BCG-infected macrophages.

To verify these results we performed an acceptor photobleaching F

To verify these results we performed an acceptor photobleaching FRET assay. Our results indicate that the trend observed in the donor-sensitized acceptor fluorescence emission FRET analysis was maintained since a significantly find more higher relative FRET efficiency was observed in cells expressing WT ζ WT versus MUT ζ MUT(Supporting Information Fig. 4C). To assess whether ζ has a structural effect on actin reorganization, we hypothesized that the positively charged ζ motifs could be involved in actin bundling, as observed for various proteins containing positively charged clusters [15, 16]. To

this end, F-actin was mixed with different concentrations of WT or MUT IC ζ proteins, stained and analyzed by

electron microscopy. As shown in Fig. 1F, while actin filaments incubated alone appear individually dispersed and disorganized in the field, addition of the WT mouse (mWT ICζ) or human (hWT ICζ) proteins induced actin organization and formation of bundles that appear as wide branches (lower middle panel) similar to those induced by the positively charged poly-l-lysine. In contrast, when the MUT ICζ was added, a disorganized actin microfilament field is observed. These results indicate that the two ζ chain RRR motifs of the mouse and human origin mediate not only the direct association with actin but also induce bundling of actin filaments. We next analyzed whether the ζ basic motifs are also responsible for its association with the cytoskeleton within T cells. To this end, we stably expressed the full RXDX-106 research buy length (WT) or the double mutated (MUT) ζ in ζ−deficient hybridoma T cells, which lack TCR cell surface expression.

Both WT and MUT ζ−expressing cells restored TCR surface expression (Supporting Information Fig. 5A), suggesting a normal association between the WT and MUT ζ and the remaining TCR subunits. Moreover, immunoprecipitation of ζ from WT and MUT cells using anti-ζ Abs (“a”–“d”), directed against different epitopes within the ζ IC region, depicted similar ζ levels precipitated from both cell types (Supporting Information Fig. 5B and C). These indicate that the ζ mutations did not affect its conformation. In all comparative experiments WT and MUT expressing Thalidomide cells expressed similar cell surface TCR levels. To assess the effect of ζ mutations on its association with the cytoskeleton, we compared the distribution of the cska- and non-cska-TCR forms between the two cell types. Total non-cska ζ levels in both WT- and MUT-expressing cells were similar to those of the parental ζ−expressing 2B4 cells from which the ζ-deficient T cells were derived (Fig. 2A). However, mutations in the basic motifs disrupted the ζ cytoskeleton association, resulting in a pronounced impairment of the cska-TCRs, with only a negligible expression (Fig. 2A).

4c) While anti-CD3-stimulated IL-10 secretion was at the same ma

4c). While anti-CD3-stimulated IL-10 secretion was at the same magnitude as bacterial antigen-stimulated secretion, the release of IFN-γ was between 16-fold (day 7) and 30-fold (day 0) higher for anti-CD3 stimulation compared selleckchem to bacterial stimulation, suggesting that the potential repertoire of IFN-γ-producing T cells was higher than the repertoire stimulated by bacterial antigens alone. In contrast, the stimulation of IL-10 secreting T cells was linked tightly to bacterial antigen stimulation. It is possible that some of the cytokine production could also be a result of activation of other monocytic spleen cells via their Toll-like-receptors or through

a downstream bystander effect. To test for a possible regulatory mechanism for the decline in cytokine production after day 7 post-injection, we examined the amount and composition Selleckchem LBH589 of a variety of cells within the spleen cell population. No significant change in the percentage of CD25-positive cells was detected (Fig. 5a), suggesting that regulatory T cells within this population were not instrumental in the down-regulation of the immune response. However, concomitant with the increase of cytokine release at day 7 we found an increase in the number of CD11b-positive

leucocytes (Fig. 5b). An overlap of CD11b staining with markers for T cells (anti-CD3), B cells (B220) and dendritic cells (anti-CD11c) was less than 2%, while on average more than 68% of these cells also stained for Gr-1, suggesting

a myeloid-derived suppressor cell phenotype (data not shown). There was no significant change in total number of spleen cells recovered from mice at the various time-points post-faecal ingestion (Fig. 5c). Similarly, changes in numbers and percentages of both CD3-positive T cells and B220-positive B cells were not significant. However, the ratio of B220/CD3-positive cells was reduced significantly from 1·54 ± 0·14 (day 0) to 1·02 ± 0·03 (day 14) as a consequence of a slight increase in percentage of T cells and a concomitant decrease in the percentage of the B cell population at days 7–14. In this study we have Flavopiridol (Alvocidib) investigated the impact of commensal faecal flora and antigen acquisition in an immune environment that developed in the absence of an enteric bacterial influence. Generally the mammalian gastrointestinal tract is populated with a highly diverse microbial flora immediately after birth. Studies employing gnotobiotic rodent colonies have shown that microbial colonization affects the general morphology, gut motility and differentiation of epithelial cell lineages [10–12]. In addition, acquisition of intestinal microflora is vital for the development of immunity. Gene expression profiling has revealed that the residential microbiota modifies genes significantly, including those involved in immune function [13,14]. Expression of several activation markers on intestinal immune cells is greatly reduced in axenic mice [11].

parapertussis infection in human populations, and our results sug

parapertussis infection in human populations, and our results suggest that concurrent B. pertussis infection may do the same. However, as far as we know, B. parapertussis infections have not emerged at high levels in the era of pertussis vaccine use, although diagnostics for B. parapertussis infections need to be improved before the picture is clear. Coinfection with these two closely related pathogens may be more common than documented in human pertussis disease and the less virulent of the pair may benefit from the immunomodulatory properties of B. pertussis. Of course, whether this mouse model is representative of human infection is

unclear. Some aspects of B. parapertussis infection in mice more closely resemble those of B. bronchiseptica than B. pertussis (Heininger et al., 2002), and it is possible that B. pertussis is better adapted to the human host GSK-3 inhibitor than B. parapertussis and would outcompete

it in a mixed infection in a Alvelestat solubility dmso human. Human volunteer experiments may be necessary to resolve these issues. This work was supported by NIH grant AI063080. We thank Galina Artamonova and Aakanksha Pant for conducting some of the preliminary mouse infection studies and Charlotte Mitchell for technical advice with BAL. “
“Vaccines are very effective at preventing infectious disease but not all recipients mount a protective immune response to vaccination. Recently, gene expression profiles of PBMC samples in vaccinated individuals have been used to predict the development of protective immunity. However, the magnitude of change in gene expression that separates vaccine responders and nonresponders is likely to be small and distributed across networks of genes, making the selection of predictive and biologically relevant genes difficult.

Here we apply a new approach to predicting vaccine response based on coordinated upregulation of sets of biologically informative genes in postvaccination gene expression profiles. We found Nintedanib (BIBF 1120) that enrichment of gene sets related to proliferation and immunoglobulin genes accurately segregated high responders to influenza vaccination from low responders and achieved a prediction accuracy of 88% in an independent clinical trial. Many of the genes in these gene sets would not have been identified using conventional, single-gene level approaches because of their subtle upregulation in vaccine responders. Our results demonstrate that gene set enrichment method can capture subtle transcriptional changes and may be a generally useful approach for developing and interpreting predictive models of the human immune response. Vaccination is one of the most effective methods of preventing human disease. However, many vaccines are not universally protective and even widely used vaccines, such as those against influenza, fail to achieve protective immunity in a significant proportion of vaccinated subjects [1].

Here, we report that FhTeg does not induce Th2 immune responses b

Here, we report that FhTeg does not induce Th2 immune responses but can induce M2-like phenotype in vivo

that modulates cytokine selleck chemicals production from CD4+ cells in response to anti-CD3 stimulation. FhTeg induces a RELMα expressing macrophage population in vitro, while in vivo, the expression of Arg1 and Ym-1/2 but not RELMα in FhTeg-stimulated macrophages was STAT6 dependent. To support this finding, FhTeg induces RELMα expression in vivo prior to the induction of IL-13. FhTeg can induce IL-13-producing peritoneal macrophages following intraperitoneal injection This study highlights the important role of FhTeg as an immune-modulatory source during F. hepatica infection and sheds further light on helminth–macrophage interactions. “
“Inflammatory disorders of the peripheral

nervous system (PNS) and central nervous system (CNS) are common, and contribute substantially to physical and emotional disability of affected individuals. Often, the afflicted are young and in their active years. In the past, physicians and scientists often had very little to offer in terms of diagnostic precision and therapeutic effectiveness. During the past two decades, both of these relative shortcomings have clearly improved. Some of the recent developments in clinical neuroimmunology are illustrated in this special edition of Clinical and Experimental Immunology. “
“Citation Karata S, Aydin Y, Ocer F, Buyru A, Balci H. Hereditary Thrombophilia, anti-beta2 glycoprotein 1 IgM, and anti-annexin V antibodies in recurrent pregnancy loss. Am J Reprod Immunol 2012; 67: 251–255 Problem click here We investigated the beta2-glycoprotein I and anti-annexin V antibodies as anti-phospholipid–cofactor antibodies; and factor V G1691A Leiden, prothrombin G20210A, and methylenetetrahydrofolate

reductase tuclazepam (MTHFR) C677T mutations as hereditary thrombophilia in recurrent pregnancy losses (RPL). Method of study Study group consisted of 84 women with recurrent pregnancy loss and control group consisted of 84 women having at least one live birth. Results Methylenetetrahydrofolate reductase C677T homozygous mutation was detected in 28.5% of the study group and in 14.2% of the controls, and the difference was highly significant (P < 0.001). Heterozygous mutation of this gene was found in 64.3% of the study population and in 38.1% of the controls, and difference in heterozygous mutation frequency was also significant (P < 0.001). Both homozygous and heterozygous mutations of PT G20210A and factor V G1691A were not different between the groups. There was no significant difference in anti-annexin V levels and anti-beta2-gp 1 levels of the groups. Conclusion We concluded that both homozygous and heterozygous mutations of MTHFR C677T were related with RPL in Caucasian women. "
“Studies have shown the IL-17A involvement in human ischemic stroke patients in vivo. Whether the IL-17A expression was originated from Th17 and could be stimulated by hypoxia remained unknown.

At 1 month, 13 out of 16 (81%) patients in the levamisole group a

At 1 month, 13 out of 16 (81%) patients in the levamisole group as compared with six out of 18 (33%) patients in the placebo group developed protective anti-tetanus IgG levels

(relative risk = 2.44, 95% confidence interval (CI) = 1.21, 4.88). From 1 to 6 months post-vaccination, one more patient in the levamisole group and two more patients in the placebo group were excluded because of renal transplantation. At 6 months, 11 out of 15 (73%) patients in the levamisole group as compared with four out of 16 (25%) patients in the placebo group still had protective anti-tetanus IgG levels (relative risk = 2.93, 95% CI = 1.19, 7.23). Supplementation of Td vaccination with levamisole may enhance seroconversion against tetanus in haemodialysis patients. Compared with healthy population, haemodialysis patients are more susceptible to infections like tetanus[1-3] and experience lower seroconversion rate following vaccination because of their impaired immune system.[3-5] One of the strategies to increase the rate of seroconversion in these patients is to boost the immune system with immunostimulatory agents.[6] Levamisole is an immunomodulatory drug that stimulates depressed T cell activity

and enhances the production of antibodies by B cells.[6, 7] This anti-helminthic drug has been reported to increase the seroconversion rate following hepatitis B virus (HBV) vaccination.[6, 7] However, the possible enhancing effects of this drug on the response rates BVD-523 purchase of other vaccines like tetanus have not been studied. Therefore, the aim of the current study was to evaluate the effect of levamisole supplementation on tetanus vaccine response rate in haemodialysis patients. This

randomized double-blind placebo-controlled trial was approved by the Institutional Review Board of Shiraz University of Medical Sciences and was done in accordance with Exoribonuclease the Declaration of Helsinki and Good Clinical Practice guidelines. Eligible participants were 20- to 80-year-old patients on regular haemodialysis in Faghihi Hospital Dialysis Center for more than 3 months who had unprotective anti-tetanus immunoglobulin G (IgG) levels as defined by the World Health Organization (WHO) (<0.1 international unit (IU)/mL). Exclusion criteria were: tetanus diphtheria (Td) vaccination in past year, leukopenia (white blood cell count < 1500 cells/mcL), immunosuppressive drug exposure in past 2 months, and recent hospitalization or history of transfusion of blood products in the past 3 months. In accordance with previous studies evaluating the effect of levamisole on HBV vaccination response in haemodialysis patients,[8, 9] a sample size of 12 patients per group was calculated considering two-sided significance level of 5%, power of 80% and response rates of 75% and 25% in levamisole and placebo groups, respectively. Considering a drop-out rate of 40%, a sample size of 20 patients per group was finalized.

There was no significant difference in the risk of acute rejectio

There was no significant difference in the risk of acute rejection, all-cause mortality, graft loss, leucopaenia or renal dysfunction. Comparing ABT-263 solubility dmso pre-emptive with prophylactic antiviral treatment there was no significant difference in CMV disease, all-cause mortality, graft loss, acute rejection or other viral, bacterial or fungal infections. CMV infection was obviously higher in the pre-emptive group as this was a prerequisite

for treatment. Leucopaenia was significantly less common with pre-emptive therapy. Results were not significantly different for low or high risk CMV status organ recipients though there were limited data addressing these patient groups. The antiviral agents compared were pre-emptive ganciclovir versus prophylactic ganciclovir,

pre-emptive valganciclovir versus prophylactic valganciclovir or valaciclovir, and pre-emptive ganciclovir versus prophylactic selleck inhibitor acyclovir. Pre-emptive oral versus intravenous ganciclovir showed no significant difference in risk of CMV disease, all-cause mortality or other infections. There was no difference between efficacy of oral or IV preparations of antiviral agent ganciclovir. A total of 15 trials (N = 1098 with 1063 included in the analyses) were included in the data synthesis. Six trials (N = 291 with 288 in the analysis) compared pre-emptive antiviral therapy with placebo or no specific therapy, eight trials (N = 785 with 753 included in the analysis) compared pre-emptive therapy with prophylaxis and the last trial compared pre-emptive oral with intravenous ganciclovir in liver transplant recipients (N = 22 all of whom were included in the analysis). The range of follow up of these studies was 3 to 18 months. Assessment of domains of methodological quality in the design and reporting of included trials identified only five (33%) trials with appropriate sequence generation and four trials (27%) with adequate allocation concealment. The majority of trials were judged as having low risk of attrition bias (93%) and seven trials (47%) had selective reporting of outcomes leading to a high risk of bias. Blinding of participants

was done in Cell Penetrating Peptide only two trials (13%) and no trials reported blinding of outcome assessment. Of the 15 trials, 5 (33%) were funded by pharmaceutical companies. Pre-emptive treatment is more effective than no treatment (Figure 1) No conclusions can be made about the relative efficacy of pre-emptive therapy and prophylaxis because of inconsistency between the results of individual trials (Figure 2). Leucopaenia is less common with pre-emptive compared with prophylaxis treatment Pre-emptive treatment for CMV disease aims to reduce the number of transplant recipients being exposed to long term prophylaxis by focusing treatment on recipients with laboratory evidence of CMV infection. Theoretically this could reduce the risk of resistant strains of CMV and late onset CMV disease, however, these outcomes were not reported in these trials.

NK cells are relatively easy to select from apheresis donations,

NK cells are relatively easy to select from apheresis donations, but although typically approximately 5 × 108

cells can be obtained relatively pure, this may not represent a sufficient number for clinical efficacy [94]. Miller and colleagues therefore sought to expand transfused NK cells in vivo. Selected NK cells from HLA identical donors were transfused into 19 patients with high-risk AML after conditioning with low-dose total body irradiation or a combination of fludarabine and cyclophosphamide. The conditioning induced a rise of IL-15 and circulating NK cell numbers which showed enhanced cytotoxicity to leukaemia lasting more than 3 weeks. Five patients Dasatinib achieved complete remission [95]. Other investigators have developed clinical-grade strategies to expand NK cells ex-vivo using B cell lines [96] or modified K562 cells [97]. Such techniques can yield 20–200-fold expansion of pure but activated NK cells over several weeks. Expanded cells are fully functional and kill leukaemia and tumour targets. Clinical trials using expanded NK cells have not yet been reported. Future developments may include combined

ex-vivo and in vivo expansion approaches. Allogeneic T cells buy Staurosporine can be raised against mHag by peptide-pulsed DC or AML cells and are being used in treatment of relapsed leukaemia after stem cell transplantation. Outside the context of SCT, the occurrence in patients of CTL specific for AML supports the possibility

of using expanded autologous antigen-specific CTL to attack AML [3,86]. Adoptive transfer of leukaemia-specific T cells presents different challenges according to whether the transfused T cells are autologous or allogeneic in origin. Treatment with allogeneic T cells requires immunosuppression of the recipient to permit at least the short-term survival of the transfused cells. Two studies of allogeneic T cell transfer in non-transplant recipients have been reported [98,99]. Haploidentical donor lymphocyte transfusions were given to patients with diverse malignancies, including 13 patients with high-risk AML. Transfusion was followed by a cytokine storm without any acetylcholine sustained cellular engraftment, but there were tumour responses including five complete remissions in the AML patients [99]. Future developments will need to focus upon ways to achieve a short controlled engraftment sufficient to confer an anti-leukaemia effect perhaps by engineering T cells to escape immune attack, which may in turn require the co-insertion of a suicide gene as a safety precaution to prevent sustained persistence and expansion of the foreign T cell clone. Autologous T cell infusions can avoid the problems of alloreactivity of patient to donor or donor to patient. Here the problem is to generate sufficient numbers of T cells with powerful anti-leukaemia activity.

For experiment in Fig 1C, 5×104 presensitized MCs were mixed wit

For experiment in Fig. 1C, 5×104 presensitized MCs were mixed with equal amount of Tregs on microscope slides coated with 0.05 mg/mL poly-L-lysine, and incubated with DNP for 1 or 20 min at 37°C. Cells were fixed with 4% paraformaldehyde for 20 min, washed and mounted with Mowiol. Phase-contrast images were acquired and scoring of the slides was performed in a blinded fashion by evaluating for each condition at least 270 MCs in randomly selected fields from three independent experiments. Nearly, 2×105 presensitized BMMCs were loaded with 1 μM Fura2-AM (Molecular Probes), diluted in 0.5% Pluronic (Molecular

Probes) in DMSO, at room temperature for 10 min. Fura2-loaded BMMCs were plated together with equal number of Tregs onto poly-L-lysine-coated PD0325901 coverslips and placed on the stage of an inverted fluorescence microscope (Olympus IX50, Olympus, Japan) equipped with a thermostated chamber (Harvard Apparatus, Navitoclax ic50 MA, USA), at 37°C. To

analyze (Ca2+)i, a region was drawn around the BMMC and the fluorescence of Fura was used to determine the intracellular levels of free Ca2+ for total 25 min after Ag challenge. The changes in (Ca2+)i are expressed as a ratio of the light emitted at 505 nm upon excitation at the two wavelengths, 340 and 380 nm (F340/F380), after background subtraction. Data were collected using the TillVision Software (Till Photonics GmBH, Germany). Images were analyzed and processed using the ImageJ (Wayne Rasband, NIH; Bethesda, MD, USA) and with custom-made imaging software (Vimmaging, VIMM Padova).

To simultaneously check MC–Treg interactions over the acquisition time, interference contrast (DIC) images were kept at the beginning and at the end of each experiment. FAD Nearly, 4×106 presensitized BMMCs and 4×106 Tregs (ratio 1:1) were challenged with 100 ng/mL DNP-HSA (Sigma-Aldrich) in Tyrode’s buffer/0.05% BSA. After 10 min, cells were fixed by the addition of glutaraldehyde to reach 3% final concentration. Cells were kept for 3 h in 3% glutaraldehyde in 0.1 M phosphate buffer, pH 7.4, post-fixed in phosphate-buffered 1% osmium tetroxide for 1.5 h, dehydrated in graded ethanol series and embedded in Epon 812. Thin sections were counterstained with uranyl acetate and lead citrate and examined in a Philips CM 12 electron microscope at 80 kV. Nearly, 1×106 presensitized BMMCs and 1×106 Tregs (ratio 1:1) were challenged with 100 ng/mL DNP-HSA (Sigma-Aldrich) in Tyrode’s buffer/0.05% BSA for 30 min. LTC4 was measured by specific immunoassay (GE Healthcare) while the histamine concentration was determined by ELISA according to the producer’s instruction (DRG Instruments GmbH, Germany). β-Hexosaminidase was determined as previously described 4. For cytokine analysis, equal numbers of IgE-sensitized BMMCs and Tregs were cultured alone or together for 24 h in the presence of 100 ng/mL DNP.