Steroid Sensitivity Research Articles

Linoleic acid metabolite leads to steroid resistant asthma features partially through NF-\u03baB

Studies have highlighted the role of nutritional and metabolic modulators in asthma pathobiology. Steroid resistance is an important clinical problem in asthma but lacks good experimental models. Linoleic acid, a polyunsaturated fatty acid, has been linked to asthma and glucocorticoid sensitivity. Its 12/15–lipoxygenase metabolite, 13-S-hydroxyoctadecadienoic acid (HODE) induces mitochondrial dysfunction, with severe airway obstruction and neutrophilic airway inflammation. Here we show that HODE administration leads to steroid unresponsiveness in an otherwise steroid responsive model of allergic airway inflammation (AAI). HODE treatment to allergic mice further increased airway hyperresponsiveness and goblet metaplasia. Treatment with dexamethasone was associated with increased neutrophilic inflammation in HODE treated allergic mice; unlike control allergic mice that showed resolution of inflammation. HODE induced loss of steroid sensitivity was associated with increased p-NFkB in mice and reduced GR-α transcript levels in cultured human bronchial epithelia. In summary, HODE modifies typical AAI to recapitulate many of the phenotypic features seen in severe steroid unresponsive asthma. We speculate that since HODE is a natural metabolite, it may be relevant to the increased asthma severity and steroid insensitivity in patients who are obese or consume high fat diets. Further characterization of HODE induced steroid insensitivity may clarify the mechanisms.

The steroid metabolome in women with premenstrual dysphoric disorder during GnRH agonist-induced ovarian suppression: effects of estradiol and progesterone addback

Clinical evidence suggests that symptoms in premenstrual dysphoric disorder (PMDD) reflect abnormal responsivity to ovarian steroids. This differential steroid sensitivity could be underpinned by abnormal processing of the steroid signal. We used a pharmacometabolomics approach in women with prospectively confirmed PMDD (n=15) and controls without menstrual cycle-related affective symptoms (n=15). All were medication-free with normal menstrual cycle lengths. Notably, women with PMDD were required to show hormone sensitivity in an ovarian suppression protocol. Ovarian suppression was induced for 6 months with gonadotropin-releasing hormone (GnRH)-agonist (Lupron); after 3 months all were randomized to 4 weeks of estradiol (E2) or progesterone (P4). After a 2-week washout, a crossover was performed. Liquid chromatography/tandem mass spectrometry measured 49 steroid metabolites in serum. Values were excluded if >40% were below the limit of detectability (n=21). Analyses were performed with Wilcoxon rank-sum tests using false-discovery rate (q<0.2) for multiple comparisons. PMDD and controls had similar basal levels of metabolites during Lupron and P4-derived neurosteroids during Lupron or E2/P4 conditions. Both groups had significant increases in several steroid metabolites compared with the Lupron alone condition after treatment with E2 (that is, estrone-SO4 (q=0.039 and q=0.002, respectively) and estradiol-3-SO4 (q=0.166 and q=0.001, respectively)) and after treatment with P4 (that is, allopregnanolone (q=0.001 for both PMDD and controls), pregnanediol (q=0.077 and q=0.030, respectively) and cortexone (q=0.118 and q=0.157, respectively). Only sulfated steroid metabolites showed significant diagnosis-related differences. During Lupron plus E2 treatment, women with PMDD had a significantly attenuated increase in E2-3-sulfate (q=0.035) compared with control women, and during Lupron plus P4 treatment a decrease in DHEA-sulfate (q=0.07) compared with an increase in controls. Significant effects of E2 addback compared with Lupron were observed in women with PMDD who had significant decreases in DHEA-sulfate (q=0.065) and pregnenolone sulfate (q=0.076), whereas controls had nonsignificant increases (however, these differences did not meet statistical significance for a between diagnosis effect). Alterations of sulfotransferase activity could contribute to the differential steroid sensitivity in PMDD. Importantly, no differences in the formation of P4-derived neurosteroids were observed in this otherwise highly selected sample of women studied under controlled hormone exposures.

The response of the Oxford classification to steroid in IgA nephropathy: a systematic review and meta-analysis.

BackgroundThe present review is aimed to evaluate the correlation between pathological features and the response to steroid in the patients with IgA nephropathy according to the Oxford classification, mesangial hypercellularity (M), endocapillary hypercellularity (E), segmental glomerulosclerosis (S), tubular atrophy and interstitial fibrosis (T).MethodsWe searched Chinese Biomedical Database, EMBASE, Cochrane Library, PubMed and MEDLINE with all spellings of “IgA nephropathy”, “Oxford Classification”, and “steroid”.Results5 studies with 637 patients were eligible for inclusion. The analysis showed that M1, S1, and T1/2 was strongly associated with the prediction to steroid resistance when compared with M0 [odds ratio (OR) 1.89, 95% confidence interval (CI) 1.01 - 3.56, P < 0.05], S0 (OR 2.24, 95% CI 0.99 - 5.08, P = 0.05) and T0 (OR 2.16, 95% CI 1.29 - 3.63, P = 0.004) respectively. There is no difference in steroid sensitivity between E0 and E1 (P = 0.55). The pooled OR of steroid resistance for E1 versus T1/2 is 0.50 (P = 0.04).ConclusionIgA nephropathy patients with serious pathological changes (M1, S1, and T1/2) were more resistant to steroid than slight ones (M0, S0, and T0), and E1 is better response to steroid therapy than T1/2.

Nasal airway epithelial cell IL-6 and FKBP51 gene expression and steroid sensitivity in asthmatic children.

BackgroundMany asthmatic patients exhibit uncontrolled asthma despite high-dose inhaled corticosteroids (ICS). Airway epithelial cells (AEC) have distinct activation profiles that can influence ICS response.ObjectivesA pilot study to identify gene expression markers of AEC dysfunction and markers of corticosteroid sensitivity in asthmatic and non-asthmatic control children, for comparison with published reports in adults.MethodsAEC were obtained by nasal brushings and primary submerged cultures, and incubated in control conditions or in the presence of 10 ng/ml TNFalpha, 10-8M dexamethasone, or both. RT-PCR-based expression of FKBP51 (a steroid hormone receptor signalling regulator), NF-kB, IL-6, LIF (an IL-6 family neurotrophic cytokine), serpinB2 (which inhibits plasminogen activation and promotes fibrin deposition) and porin (a marker of mitochondrial mass) were determined.Results6 patients without asthma (median age 11yr; min-max: 7–13), 8 with controlled asthma (11yr, 7–13; median daily fluticasone dose = 100 μg), and 4 with uncontrolled asthma (12yr, 7–14; 1000 μg fluticasone daily) were included. Baseline expression of LIF mRNA was significantly increased in uncontrolled vs controlled asthmatic children. TNFalpha significantly increased LIF expression in uncontrolled asthma. A similar trend was observed regarding IL-6. Dexamethasone significantly upregulated FKBP51 expression in all groups but the response was blunted in asthmatic children. No significant upregulation was identified regarding NF-kB, serpinB2 and porin.ConclusionLIF and FKBP51 expression in epithelial cells were the most interesting markers of AEC dysfunction/response to corticosteroid treatment.

A prospective randomized controlled study: Theophylline on oxidative stress and steroid sensitivity in chronic obstructive pulmonary disease patients.

Objective:Oxidative stress is involved in the pathogenesis of chronic obstructive pulmonary disease (COPD). Corticosteroid fails to suppress inflammation and oxidative stress due to steroid resistance. Theophylline has an effect on histone deacetylase (HDAC) activity and improves steroid sensitivity in COPD. Given changes in oxidative stress associated with diminished corticosteroid effects, a clinical study in which antioxidants and free radicals are estimated can suggest a correlation between antioxidants, theophylline, and corticosteroid sensitivity.Materials and Methods:A randomized controlled study was conducted in 60 participants divided into 4 groups: Group I (controls) - 15 normal healthy volunteers, Group II - COPD patients who received theophylline 300 mg + salbutamol 8 mg, Group III - patients who inhaled budesonide 400 μg + salbutamol 8 mg, and Group IV – theophylline 300 mg + inhaled budesonide 400 μg + salbutamol 8 mg 12 weeks. Blood samples were collected at the time of diagnosis and at 4-week interval for 3 months from all the groups and antioxidant parameters, spirometric % forced expiratory volume in 1 s (FEV1) were measured.Results:The mean difference between groups was analyzed using one-way ANOVA. There was a significant increase in antioxidant enzymes such as catalase, glutathione (GSH) serum transferase, (P < 0.05), reduced GSH, and superoxide dismutase (P < 0.01) and a significant decrease in lipid peroxidation (P < 0.01) at 12 weeks of the study period. Postbronchodilator FEV1 values have also shown a significant increase at 12 weeks (P < 0.01).Conclusion:Theophylline increases the expression and activity of HDAC and improves steroid sensitivity thereby decreases oxidative stress. Hence, novel therapeutic strategy is therefore the reversal of this corticosteroid resistance by increasing the expression and activity of HDAC achieved using corticosteroids along with theophylline.

A Randomized Controlled Trial of Intravenous versus Oral Cyclophosphamide in Steroid-resistant Nephrotic Syndrome in Children.

This is a randomized, parallel group, active-controlled trial to compare the efficacy of intravenous cyclophosphamide (IVCP) with oral cyclophosphamide (OCP) in patients with steroid-resistant nephrotic syndrome (SRNS) in children. Fifty consecutive children with idiopathic SRNS were biopsied and then randomized to receive either OCP at a dose of 2 mg/kg/day for 12 weeks or IVCP at a dose of 500 mg/m2/month for 6 months. Both groups received tapering doses of oral steroids. The response was evaluated in terms of induction of complete remission (CR) or partial remission (PR), time to remit, and side effects. The groups were followed up to determine the duration of remission, percentage of patients who remain in sustained remission for more than 1 year after completion of therapy, change in steroid response status, progression to chronic kidney disease stage 3 or more. Of the fifty patients, OCP was given to 25 children and IVCP to 25 children. The demographic data, histopathology, biochemical profile, and duration of follow-up in the two groups were comparable. The rates of induction of CR were 52% versus 44% and of PR were 8% versus 8% in the intravenous (IV) and oral group, respectively. Time to remit was shorter with OCP than IVCP (53 days vs. 84.4 days). Incidence of side effects (both major and minor) was 36% in IVCP versus 20% in OCP group. The actuarial cumulative sustained remission in our study was 12% in IVCP compared with 16% in OCP at 1 year after completion of therapy. Twelve percent children in both the groups exhibited restoration of steroid sensitivity. Thus, in our study, overall, more than half of SRNS patients showed initial response to cyclophosphamide, but only one-fourth patients had sustained remission on follow-up. OCP and IVCP were equally efficacious and safe in idiopathic SRNS in children.

IL-7 Receptor Mutations and Steroid Resistance in Pediatric T cell Acute Lymphoblastic Leukemia: A Genome Sequencing Study.

BackgroundPediatric acute lymphoblastic leukemia (ALL) is the most common childhood cancer and the leading cause of cancer-related mortality in children. T cell ALL (T-ALL) represents about 15% of pediatric ALL cases and is considered a high-risk disease. T-ALL is often associated with resistance to treatment, including steroids, which are currently the cornerstone for treating ALL; moreover, initial steroid response strongly predicts survival and cure. However, the cellular mechanisms underlying steroid resistance in T-ALL patients are poorly understood. In this study, we combined various genomic datasets in order to identify candidate genetic mechanisms underlying steroid resistance in children undergoing T-ALL treatment.Methods and FindingsWe performed whole genome sequencing on paired pre-treatment (diagnostic) and post-treatment (remission) samples from 13 patients, and targeted exome sequencing of pre-treatment samples from 69 additional T-ALL patients. We then integrated mutation data with copy number data for 151 mutated genes, and this integrated dataset was tested for associations of mutations with clinical outcomes and in vitro drug response. Our analysis revealed that mutations in JAK1 and KRAS, two genes encoding components of the interleukin 7 receptor (IL7R) signaling pathway, were associated with steroid resistance and poor outcome. We then sequenced JAK1, KRAS, and other genes in this pathway, including IL7R, JAK3, NF1, NRAS, and AKT, in these 69 T-ALL patients and a further 77 T-ALL patients. We identified mutations in 32% (47/146) of patients, the majority of whom had a specific T-ALL subtype (early thymic progenitor ALL or TLX). Based on the outcomes of these patients and their prednisolone responsiveness measured in vitro, we then confirmed that these mutations were associated with both steroid resistance and poor outcome.To explore how these mutations in IL7R signaling pathway genes cause steroid resistance and subsequent poor outcome, we expressed wild-type and mutant IL7R signaling molecules in two steroid-sensitive T-ALL cell lines (SUPT1 and P12 Ichikawa cells) using inducible lentiviral expression constructs. We found that expressing mutant IL7R, JAK1, or NRAS, or wild-type NRAS or AKT, specifically induced steroid resistance without affecting sensitivity to vincristine or L-asparaginase. In contrast, wild-type IL7R, JAK1, and JAK3, as well as mutant JAK3 and mutant AKT, had no effect. We then performed a functional study to examine the mechanisms underlying steroid resistance and found that, rather than changing the steroid receptor’s ability to activate downstream targets, steroid resistance was associated with strong activation of MEK-ERK and AKT, downstream components of the IL7R signaling pathway, thereby inducing a robust antiapoptotic response by upregulating MCL1 and BCLXL expression. Both the MEK-ERK and AKT pathways also inactivate BIM, an essential molecule for steroid-induced cell death, and inhibit GSK3B, an important regulator of proapoptotic BIM. Importantly, treating our cell lines with IL7R signaling inhibitors restored steroid sensitivity. To address clinical relevance, we treated primary T-ALL cells obtained from 11 patients with steroids either alone or in combination with IL7R signaling inhibitors; we found that including a MEK, AKT, mTOR, or dual PI3K/mTOR inhibitor strongly increased steroid-induced cell death. Therefore, combining these inhibitors with steroid treatment may enhance steroid sensitivity in patients with ALL. The main limitation of our study was the modest cohort size, owing to the very low incidence of T-ALL.ConclusionsUsing an unbiased sequencing approach, we found that specific mutations in IL7R signaling molecules underlie steroid resistance in T-ALL. Future prospective clinical studies should test the ability of inhibitors of MEK, AKT, mTOR, or PI3K/mTOR to restore or enhance steroid sensitivity and improve clinical outcome.

Development and validation of a novel bioassay to determine glucocorticoid sensitivity.

BackgroundGlucocorticoids (GCs) remain the first line treatment for almost all non-infectious inflammatory diseases, ranging from acute asthma to rheumatoid arthritis. However, across all conditions, patients have a variable response to GCs with approximately 30% being non-responders. This group of GC resistant patients is typically exposed to high-dose GCs and their side-effects before more appropriate immunotherapy is instituted. Hence, there is a pressing clinical need for a predictive biomarker of GC responsiveness. The availability of such a tool would also enable patient stratification for the conduct of smart clinical trials in GC resistance. Lymphocyte GC sensitivity has been shown to be closely associated with clinical GC sensitivity in a number of inflammatory diseases. However, the method for determining in vitro GC response is not standardized and requires the use of specialist equipment, including a radioisotope to quantify cellular proliferation, making it challenging to translate into clinical practice.ResultsHere we describe the optimization and validation of a novel non-radioactive in vitro bioassay based on measuring cellular proliferation by incorporation of bromodeoxyuridine (BrdU), termed the BrdU incorporation in lymphocyte steroid sensitivity assay (BLISS). In comparison to the current gold standard lymphocyte GC sensitivity assay in 101 healthy control samples, BLISS has an area under receiver operating characteristic of 0.82 and a sensitivity of 83% for correctly identifying GC resistant subjects.ConclusionsThe performance of the novel BLISS bioassay makes it a strong candidate biomarker for clinical application. It now requires validation in a prospective patient cohort.Electronic supplementary materialThe online version of this article (doi:10.1186/s40364-016-0079-y) contains supplementary material, which is available to authorized users.

Urine IL-8 is the Predictive Biomarker of Steroid Sensitivity in Patients with Idiopathic Nephrotic Syndrome

Urine IL-8 is the Predictive Biomarker of Steroid Sensitivity in Patients with Idiopathic Nephrotic Syndrome

Reciprocal Regulation of 11β-HSDs May Predict Steroid Sensitivity in Childhood Nephrotic Syndrome.

Childhood nephrotic syndrome, in which steroid-dependence occurs concurrently with steroid-resistance, requires aggressive therapy to prevent relapse. Predictive biomarkers that can be used to stratify treatment are urgently needed. Here we report that reciprocal regulation of the glucocorticoid metabolizing enzymes, 11β-hydroxysteroid dehydrogenase types 1 and 2, is associated with steroid-responsiveness and disease remission in childhood nephrotic syndrome, potentially providing a marker to identify patients in which aggressive therapy is required.

SXR rs3842689: a prognostic factor for steroid sensitivity or resistance in pediatric idiopathic nephrotic syndrome.

of the study was to analyse the impact of SXR rs3842689 polymorphism on the response to corticosteroids in pediatric idiopathic nephrotic syndrome. 66 children (56 steroid-sensitive, ten steroid-resistant) were studied for SXR gene polymorphism distribution. Steroid sensitive patients accounted for 96% of cases with In/In polymorphism, but only for 53% of cases with Del/Del polymorphism At odds ratio analysis, Del/Del represented a clear risk factor of steroid resistance (OR: 20.57; p = 0.009), while In/In was a favourable prognostic factor of steroid sensitivity. The analysis of SXR polymorphism is a promising tool to predict both the favourable response to corticosteroids and the risk of developing steroid resistance.

In vitro sensitivity to methyl-prednisolone is associated with clinical response in pediatric idiopathic nephrotic syndrome.

The aim of this study was to evaluate the in vitro steroid sensitivity as a predictor of clinical response to glucocorticoids in childhood idiopathic nephrotic syndrome (INS). Seventy-four patients (median age 4.33, interquartile range [IQR] 2.82-7.23; 63.5% male) were enrolled in a prospective multicenter study: in vitro steroid inhibition of patients' peripheral blood mononuclear cell proliferation was evaluated by [methyl-(3) H] thymidine incorporation assay at disease onset (T0) and after 4 weeks (T4) of treatment. Steroid dependence was associated with increased in vitro sensitivity at T4 assessed both as drug concentration inducing 50% of inhibition (IC50 ; odds ratio [OR] = 0.48, 95% confidence interval [CI] = 0.24-0.85; P = 0.0094) and maximum inhibition at the highest drug concentration (Imax ; OR = 1.13, 95% CI = 1.02-1.31; P = 0.017). IC50 > 4.4 nM and Imax < 92% at T4 were good predictors for optimal clinical response. These results suggest that this test may be useful for predicting the response to glucocorticoid therapy in pediatric INS.

Evolution of corticosteroid specificity for human, chicken, alligator and frog glucocorticoid receptors

We investigated the evolution of the response of human, chicken, alligator and frog glucocorticoid receptors (GRs) to dexamethasone, cortisol, cortisone, corticosterone, 11-deoxycorticosterone, 11-deoxycortisol and aldosterone. We find significant differences among these vertebrates in the transcriptional activation of their full length GRs by these steroids, indicating that there were changes in the specificity of the GR for steroids during the evolution of terrestrial vertebrates. To begin to study the role of interactions between different domains on the GR in steroid sensitivity and specificity for terrestrial GRs, we investigated transcriptional activation of truncated GRs containing their hinge domain and ligand binding domain (LBD) fused to a GAL4 DNA binding domain (GAL4-DBD). Compared to corresponding full length GRs, transcriptional activation of GAL4-DBD_GR-hinge/LBD constructs required higher steroid concentrations and displayed altered steroid specificity, indicating that interactions between the hinge/LBD and other domains are important in glucocorticoid activation of these terrestrial GRs.

MicroRNA-21 drives severe, steroid-insensitive experimental asthma by amplifying phosphoinositide 3-kinase–mediated suppression of histone deacetylase 2

Severe steroid-insensitive asthma is a substantial clinical problem. Effective treatments are urgently required, however, their development is hampered by a lack of understanding of the mechanisms of disease pathogenesis. Steroid-insensitive asthma is associated with respiratory tract infections and noneosinophilic endotypes, including neutrophilic forms of disease. However, steroid-insensitive patients with eosinophil-enriched inflammation have also been described. Themechanisms that underpin infection-induced, severe steroid-insensitive asthma can be elucidated by using mouse models of disease. We sought to develop representative mouse models of severe, steroid-insensitive asthma and to use them to identify pathogenic mechanisms and investigate new treatment approaches. Novel mouse models of Chlamydia, Haemophilus influenzae, influenza, and respiratory syncytial virus respiratorytract infections and ovalbumin-induced, severe, steroid-insensitive allergic airway disease (SSIAAD) in BALB/c mice were developed and interrogated. Infection induced increases in the levels of microRNA (miRNA)-21 (miR-21) expression in the lung during SSIAAD, whereas expression of the miR-21 target phosphatase and tensin homolog was reduced. This was associated with an increase in levels of phosphorylated Akt, an indicator of phosphoinositide 3-kinase (PI3K) activity, and decreased nuclear histone deacetylase (HDAC)2 levels. Treatment with an miR-21-specific antagomir (Ant-21) increased phosphatase and tensin homolog levels. Treatment with Ant-21, or the pan-PI3K inhibitor LY294002, reduced PI3K activity and restored HDAC2 levels. This led to suppression of airway hyperresponsiveness and restored steroid sensitivity to allergic airway disease. These observations were replicated with SSIAAD associated with 4 different pathogens. We identify a previously unrecognized role for anmiR-21/PI3K/HDAC2 axis in SSIAAD. Our data highlight miR-21 as a novel therapeutic target for the treatment of this form of asthma.

Andrographolide Restores Steroid Sensitivity To Block Lipopolysaccharide/IFN-γ-Induced IL-27 and Airway Hyperresponsiveness in Mice.

LPS and IFN-γ alone or in combination have been implicated in the development of steroid resistance. Combined LPS/IFN-γ strongly upregulates IL-27 production, which has been linked to steroid-resistant airway hyperresponsiveness (AHR). Andrographolide, a bioactive molecule isolated from the plant Andrographis paniculata, has demonstrated anti-inflammatory and antioxidant properties. The present study investigated whether andrographolide could restore steroid sensitivity to block LPS/IFN-γ-induced IL-27 production and AHR via its antioxidative property. The mouse macrophage cell line Raw 264.7, mouse primary lung monocytes/macrophages, and BALB/c mice were treated with LPS/IFN-γ, in the presence and absence of dexamethasone and/or andrographolide. Levels of IL-27 in vitro and in vivo were examined and mouse AHR was assessed. Dexamethasone alone failed to inhibit LPS/IFN-γ-induced IL-27 production and AHR in mice. Andrographolide significantly restored the suppressive effect of dexamethasone on LPS/IFN-γ-induced IL-27 mRNA and protein levels in the macrophage cell line and primary lung monocytes/macrophages, mouse bronchoalveolar lavage fluid and lung tissues, and AHR in mice. LPS/IFN-γ markedly reduced the nuclear level of histone deacetylase (HDAC)2, an essential epigenetic enzyme that mediates steroid anti-inflammatory action. LPS/IFN-γ also decreased total HDAC activity but increased the total histone acetyltransferase/HDAC activity ratio in mouse lungs. Andrographolide significantly restored nuclear HDAC2 protein levels and total HDAC activity, and it diminished the total histone acetyltransferase/HDAC activity ratio in mouse lungs exposed to LPS/IFN-γ, possibly via suppression of PI3K/Akt/HDAC2 phosphorylation, and upregulation of the antioxidant transcription factor NF erythroid-2-related factor 2 level and DNA binding activity. Our data suggest that andrographolide may have therapeutic value in resensitizing steroid action in respiratory disorders such as asthma.

Blocking CD28 signal in steroid resistant asthma

Abstract To investigate the mechanism of steroid resistance in severe asthma, effect of CD28 signal blockade on T cell activation and asthma model was analyzed. PBMC obtained from mild (steroid sensitive, SS), steroid dependent (SD), and steroid resistant (SR) asthmatics were stimulated with mitogens. Der f 2-specific Th clones were established and effects of glucocorticoids (GCs) on the proliferation and cytokine synthesis were analyzed. Steroid responsiveness of murine Th clones reactive to ovalbumin were analyzed. Unprimed BALB/c mice were transferred with these clones and then antigen challenged. Effect of GC on BALF eosinophilia was evaluated. CTLA4-Ig was administered through nasal inhalation or venous injection. IL-5 production by PBMC of SS asthmatics was significantly reduced after ICS administration, but that of SD asthma remained high. IC50 values for the suppression of cytokine synthesis and proliferation responses by dexamethasone was not different among SS, SD, or SR asthmatics. Addition of CD28 signal induced steroid resistance in IL-2 and PI-3 kinase dependent manner. Murine SS and SR Th clones were selected based on the steroid sensitivity of their proliferation responses in vitro. Airway infiltration of eosinophils and lymphocytes of mice transferred with SS clones were effectively inhibited by GC. In contrast, those of mice transferred with SR clones were not significantly inhibited. Administration of CTLA4-Ig significantly suppressed the proliferation of GC-treated SR clones in vitro, and the BALF eosinophilia of mice transferred with SR clones in vivo. Costimulatory signal mediated through CD28 seems crucial for the induction of steroid resistance and might be a target for therapeutic intervention.

β-Glucan exacerbates allergic asthma independent of fungal sensitization and promotes steroid-resistant TH2/TH17 responses

Allergic sensitization to fungi has been associated with asthma severity. As a result, it has been largely assumed that the contribution of fungi to allergic disease is mediated through their potent antigenicity. We sought to determine the mechanism by which fungi affect asthma development and severity. We integrated epidemiologic and experimental asthma models to explore the effect of fungal exposure on asthma development and severity. We report that fungal exposure enhances allergen-driven TH2 responses, promoting severe allergic asthma. This effect is independent of fungal sensitization and can be reconstituted with β-glucan and abrogated by neutralization of IL-17A. Furthermore, this severe asthma is resistant to steroids and characterized by mixed TH2 and TH17 responses, including IL-13+IL-17+CD4+ double-producing effector Tcells. Steroid resistance is dependent on fungus-induced TH17 responses because steroid sensitivity was restored in IL-17rc-/- mice. Similarly, in children with asthma, fungal exposure was associated with increased serum IL-17A levels and asthma severity. Our data demonstrate that fungi are potent immunomodulators and have powerful effects on asthma independent of their potential to act as antigens. Furthermore, our results provide a strong rationale for combination treatment strategies targeting IL-17A for this subgroup of fungus-exposed patients with difficult-to-treat asthma.

The Value of Monitoring the Serum Concentration of Mycophenolate Mofetil in Children with Steroid-Dependent/Frequent Relapsing Nephrotic Syndrome

Background: Mycophenolate mofetil (MMF) is an alternative treatment strategy in children with steroid sensitivity who have frequent relapses or steroid-dependent nephrotic syndrome (FRNS/SDNS). Methods: From January 2009 to January 2015, 31 cases of children with FRNS/SDNS were prospectively recruited and administered MMF and prednisone; then, serum samples were collected, and the area under the curve (AUC) of mycophenolic acid (MPA-AUC) was calculated. Results: A MPA-AUC of 27.99 μg·h/ml had a diagnostic sensitivity of 65.2% and a specificity of 87.5% in discriminating relapsing from non-relapsing patients (receiver operating characteristic-AUC 0.848). The 31 patients were then grouped according to the results of the MPA-AUC as follows: low-AUC group, <30 μg·h/ml and high-AUC group, ≥30 μg·h/ml. The results indicated that there was a significant difference in the remission rate between the groups (χ² = 6.645, p = 0.01) during the 6 months of follow-up. Compared with the results before MMF therapy, the steroid dosage in both groups was significantly reduced at the 6- and 12-month follow-ups. Furthermore, the steroid dose was reduced more significantly in the high-AUC group than in the low-AUC group (0.447 ± 0.254 vs. 0.219 ± 0.161 mg/kg/day, p = 0.006) at the 6-month follow-up. Compared with the low-AUC group at the 6-month follow-up, the number of patients with relapse and relapse episodes in the high-AUC group were also significantly reduced (7/16 vs. 1/15, p = 0.037, and 15/27 vs. 1/29, p = 0.014, respectively). Conclusions: MMF is a reasonable treatment choice to reduce the number of relapse episodes and steroid administration in children with FRNS/SDNS. Moreover, children in the high-AUC group (MPA-AUC ≥30 μg·h/ml) tended to require lower steroid doses and had greater remission rates than the patients in the low-AUC group (<30 μg·h/ml) at the 6-month follow-up.

New treatment options for alcoholic hepatitis.

The burden of alcoholic liver disease has rapidly grown in the past two decades and is expected to increase further in the coming years. Alcoholic hepatitis, the most florid presentation of alcoholic liver disease, continues to have high morbidity and mortality, with significant financial and healthcare burden with limited treatment options. Steroids remain the current standard of care in severe alcoholic hepatitis in carefully selected patients. No specific treatments are available for those patients who are steroid ineligible, intolerant or unresponsive. Liver transplant has shown good short-term outcome; however, feasibility, ethical and economic concerns remain. Modification of gut microbiota composition and their products, such as lipopolysaccharide, nutritional interventions, immune modulation, increasing steroid sensitivity, genetic polymorphism and epigenetic modification of alcohol induced liver damage, augmenting hepatic regeneration using GCSF are potential therapeutic avenues in steroid non-responsive/ineligible patients. With better understanding of the pathophysiology, using "Omics" platforms, newer options for patients with alcoholic hepatitis are expected soon.

Lymphangioleiomyomatosis: Current understanding and potential treatments.

Lymphangioleiomyomatosis (LAM) is a rare neoplastic disease affecting predominantly young women. Clinical symptoms of this progressive disease include dyspnoea, cough, recurrent pneumothorax, hemoptysis and chylothorax. LAM is generally aggressive in nature and ultimately results in respiratory failure. Important hallmark features of this metastatic disease include the formation of lesions of abnormal smooth muscle cells, cystic destruction of the lung tissue and lymphangiogenesis affecting the lungs, abdomen and lymphatics. Research over the last 10-15 years has significantly enhanced our understanding of the molecular and cellular processes associated with LAM. These processes include mutational inactivation of the tuberous sclerosis complex genes, TSC1 and TSC2, activation of the mammalian target of rapamycin (mTOR) pathway, enhanced cell proliferation and migration, lymphangiogenesis, metastatic spread through the blood and lymphatic circulations, sex steroid sensitivity and dysregulated autophagy. Despite this increased knowledge there is currently no cure for LAM and treatment options remain limited. Whilst the mTOR inhibitor rapamycin has shown some benefit in patients with LAM, with stabilisation of lung function and improved quality of life, cessation of treatment results in recurrence of the disease progression. This highlights the urgent need to identify novel targets and new treatment regimens. The focus of this review is to summarise our current understanding of the cellular and molecular processes associated with LAM and highlight emerging treatments.