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Myeloid derived suppressor cells play a critical role in T cell suppression in cancer. Here, we discuss the mechanisms of how MDSC suppress CD4(+) or CD8(+) T cells in an antigen dependent or non-dependent manner., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Elevations of cytosolic Ca2+ from the endoplasmic reticulum (ER) regulate a diverse range of cellular processes. When these luminal stores become depleted, the transmembrane ER protein Stim1 oligomerizes and translocates within the ER membrane to puncta junctions to couple with Orai1 channels, activating store-operated calcium entry (SOCE). Stim1 oligomerization and puncta formation have generally been associated with its luminal domains, however, studies have implicated that the cytoplasmic domains may contribute to this oligomerization. Studies have also suggested that intermediate or regulating elements may be required to fine-tune puncta formation and activation of SOCE. Here we made fusion proteins of Stim1 and Orai1 with FRB and FKBP12 domains that associate in the presence of rapamycin. Rapamycin-induced coupling of Stim1 to Stim1, Orai1 to Orai1 and Stim1 to Orai1 was found to be insufficient for puncta formation. Rapamycin was then used to recruit the cytosolic Ca2+ buffer protein parvalbumin (Pav) to Stim1 in order to buffer the local cytosolic Ca2+ near the ER membrane. Interestingly, Pav buffering near the ER caused puncta formation that was indistinguishable from those caused by thapsigargin. Our results suggest that Stim1 oligomerization and puncta formation may be additionally regulated either by local Ca2+ levels near the ER membrane or by as yet unidentified Ca2+-dependent proteins interacting with the cytoplasmic domains of Stim1., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Myeloid-derived suppressor cells (MDSC) play a major role in cancer-related immune suppression, yet the nature of this suppression remains controversial. In this study, we evaluated the ability of MDSCs to elicit CD4(+) T-cell tolerance in different mouse tumor models. In contrast to CD8(+) T-cell tolerance, which could be induced by MDSCs in all the tumor models tested, CD4(+) T-cell tolerance could be elicited in only one of the models (MC38) in which a substantial level of MHC class II was expressed on MDSCs compared with control myeloid cells. Mechanistic investigations revealed that MDSCs deficient in MHC class II could induce tolerance to CD8(+) T cells but not to CD4(+) T cells. Unexpectedly, antigen-specific CD4(+) T cells (but not CD8(+) T cells) could dramatically enhance the immune suppressive activity of MDSCs by converting them into powerful nonspecific suppressor cells. This striking effect was mediated by direct cell-cell contact through cross-linking of MHC class II on MDSCs. We also implicated an Ets-1 transcription factor-regulated increase in expression of Cox-2 and prostaglandin E2 in MDSCs in mediating this effect. Together, our findings suggest that activated CD4(+) T cells that are antigen specific may enhance the immune suppressive activity of MDSCs, a mechanism that might serve normally as a negative feedback loop to control immune responses that becomes dysregulated in cancer.

Carbapenem resistance among clinical isolates of Enterobacteriaceae, especially Escherichia coli and Klebsiella pneumoniae, is largely conferred by metallo-β-lactamase (MBL). Fifty-one non repetitive isolates of carbapenem-resistant (Meropenem and Imipenem) E. coli and K. pneumoniae were studied to determine the molecular mechanism for resistance. Presence of blaNDM and blaVIM was determined by polymerase chain reaction (PCR) and DNA sequencing. blaNDM was detected from majority of carbapenem-resistant K. pneumoniae (75%) and E. coli (66.6%). Timely detection and appropriate and aggressive infection control measures are required to control the spread of these bacteria in healthcare settings.

Purpose of Review: In this review, we describe the 'state-of-the-art' in our knowledge of asthma and what gaps exist, which can be exploited in the future for effective translation of our knowledge from the bench or population studies to diagnosis and therapy., Recent Findings: The advent of microbiome research has expanded the potential role of microbes in asthma. There has been a significant increase in our understanding of the pathologic, genetic, cellular and molecular mechanisms of asthma. Nonetheless, the contribution of microbes to the genesis, exacerbation and treatment of asthma are poorly understood., Summary: Asthma is a complex chronic disease of the lung whose incidence is growing at all ages despite the progress that has been made in the areas of diagnosis and treatment of asthma. The complexity is partly due to the environmental insults such as allergens and microbial infections that play differential roles in the pathogenesis of childhood vis-à-vis elderly asthma. Microbes may play important roles in the exacerbation of asthma and hence in the comorbidities due to asthma, and also in the causation of asthma.

Bisphosphonates are routinely used in the prevention and treatment of osteoporosis. Osteonecrosis of the jaw is known to be an important but rare complication of bisphosphonate usage. We present our experience with two patients of osteonecrosis of the jaw due to bisphosphonate usage.

We introduce a variation density function that profiles the relationship between multiple scalar fields over isosurfaces of a given scalar field. This profile serves as a valuable tool for multifield data exploration because it provides the user with cues to identify interesting isovalues of scalar fields. Existing isosurface-based techniques for scalar data exploration like Reeb graphs, contour spectra, isosurface statistics, etc., study a scalar field in isolation. We argue that the identification of interesting isovalues in a multifield data set should necessarily be based on the interaction between the different fields. We demonstrate the effectiveness of our approach by applying it to explore data from a wide variety of applications.

Synthesis of a series of novel hexahydrochromenopyrrole analogues has been accomplished through an intramolecular 1,3-dipolar cycloaddition (1,3-DC reaction) of azomethine ylides, generated by the aldehyde induced decarboxylation of secondary amino acids. These compounds were screened for antibacterial and antifungal activities against six human pathogenic bacteria and three human pathogenic fungi and found to have good antimicrobial properties against most of the microorganisms., (Copyright © 2010 Elsevier Ltd. All rights reserved.)

The temporal proteome response of Medicago truncatula suspension cell cultures to yeast elicitation (which mimics fungal infection) was investigated using two-dimensional polyacrylamide gel electrophoresis (2-DE) and nanoliquid chromatography coupled to tandem mass spectrometry (nano LC-MS/MS). Reproducibility of 2-DE was assessed using the number of the visualized protein spots and spot volume. Average coefficient of variation was determined to be less than 6% for the number of spots and around 50% for spot volume. About 4% of the total visualized proteins, that is, 34 out of 861, were differentially accumulated in the suspension cells 24 h after yeast elicitation, including isoflavononid biosynthetic enzymes and a putative laccase. The induction of the putative laccase was highly correlated with the polymerization of phenolics such as 4-hydroxybenzoic acid, 4-hydroxybenzaldehyde, and ferulic acid into cell walls. In contrast, lignin was only induced at the later stages of the temporal study, indicating that this specific laccase is primarily involved in cell wall modifications and/or fortifications rather than in lignification in response to yeast elicitation.

Graft-versus-host disease (GVHD) is a frequent complication after hematopoietic cell transplant (HCT). Tissue damage as a result of chemoradiation injury is the initiating event in the pathogenesis of acute GVHD. Variations in DNA repair can influence the amount of tissue damage in response to alkylating agents and ionizing radiation used as conditioning during HCT. As DNA damage caused by these agents is repaired by the base excision repair (BER) pathway, we hypothesized that single-nucleotide polymorphisms (SNPs) in BER pathway will be associated with GVHD after HCT. Hence, we analyzed 179 SNPs in BER pathway in 470 recipients of allogeneic HCT for association with acute and chronic GVHD. In multivariate analysis, one SNP (rs6844176) in RFC1 (replication factor C (activator 1)) gene was independently associated with a higher risk of grade II-IV acute GVHD (relative risk (RR): 1.39, 95% confidence interval (CI): 1.14-1.70, P=0.001), and showed a trend toward higher risk of grade III-IV acute GVHD (RR: 1.33, 95% CI: 0.95-1.85, P=0.09). One SNP in PARP1 gene (rs1805410) was associated with a higher risk of chronic GVHD (RR: 1.81, 95% CI: 1.29-2.54, P=0.001). These results show that SNPs in the BER pathway can be used as genetic biomarkers to predict those at high risk for GVHD toward whom novel prophylactic strategies could be targeted.

Dendritic cells (DCs), a type of professional antigen-presenting cells, are responsible for initiation and maintenance of immune responses. Here we report that a substantial proportion of DCs in tumor-bearing mice and people with cancer have high amounts of triglycerides as compared with DCs from tumor-free mice and healthy individuals. In our studies, lipid accumulation in DCs was caused by increased uptake of extracellular lipids due to upregulation of scavenger receptor A. DCs with high lipid content were not able to effectively stimulate allogeneic T cells or present tumor-associated antigens. DCs with high and normal lipid levels did not differ in expression of major histocompatibility complex and co-stimulatory molecules. However, lipid-laden DCs had a reduced capacity to process antigens. Pharmacological normalization of lipid abundance in DCs with an inhibitor of acetyl-CoA carboxylase restored the functional activity of DCs and substantially enhanced the effects of cancer vaccines. These findings suggest that immune responses in cancer can be improved by manipulating the lipid levels in DCs.

Alkylating agents with or without ionizing radiation are frequently used in pretransplant conditioning regimens. Damage induced by these agents is commonly repaired by the base excision repair (BER) pathway. Hence, we hypothesized that genetic polymorphisms in the BER pathway will be associated with posthematopoietic cell transplant (HCT) outcomes. We evaluated the association between single nucleotide polymorphisms (SNPs) (n = 179) in the BER pathway with treatment-related mortality (TRM) at 1 year and disease relapse in a cohort of 470 recipients who underwent allogeneic HCT for treatment of hematologic malignancies at the University of Minnesota. After adjustment for age at transplant, donor type, race, and conditioning regimen, 4 SNPs in OGGI, LIG3, and MUTYH genes (rs159153, rs3135974, rs3219463, and rs3219476) were associated with increased risk of TRM, whereas 2 SNPs in the TDG gene (rs167715 and rs2374327) were associated with decreased risk of TRM at 1 year (P or=4 deleterious alleles versus 14% for

Objective: More than 75% of Indian toddlers are anemic. Data on factors associated with anemia in India are limited. The objective of this study was to determine biological, nutritional, and socioeconomic risk factors for anemia in this vulnerable age group., Methods: We conducted a cross-sectional study of children aged 12 to 23 months in 2 rural districts of Karnataka, India. Children were excluded if they were unwell or had received a blood transfusion. Hemoglobin, ferritin, folate, vitamin B(12), retinol-binding protein, and C-reactive protein (CRP) levels were determined. Children were also tested for hemoglobinopathy, malaria infection, and hookworm infestation. Anthropometric measurements, nutritional intake, family wealth, and food security were recorded. In addition, maternal hemoglobin level was measured., Results: Anemia (hemoglobin level < 11.0 g/dL) was detected in 75.3% of the 401 children sampled. Anemia was associated with iron deficiency (low ferritin level), maternal anemia, and food insecurity. Children's ferritin levels were directly associated with their iron intake and CRP levels and with maternal hemoglobin level and inversely associated with continued breastfeeding and the child's energy intake. A multivariate model for the child's hemoglobin level revealed associations with log(ferritin level) (coefficient: 1.20; P < .001), folate level (0.05; P < .01), maternal hemoglobin level (0.16; P < .001), family wealth index (0.02; P < .05), child's age (0.05 per month; P < .005), hemoglobinopathy (-1.51; P < .001), CRP level (-0.18; P < .001), and male gender (-0.38; P < .05). Wealth index and food insecurity could be interchanged in this model., Conclusions: Hemoglobin level was primarily associated with iron status in these Indian toddlers; however, maternal hemoglobin level, family wealth, and food insecurity were also important factors. Strategies for minimizing childhood anemia must include optimized iron intake but should simultaneously address maternal anemia, poverty, and food insecurity.

Myeloid-derived suppressor cells are one of the major factors responsible for immune suppression in cancer. They also contribute to limited efficacy of current vaccination strategies. Here, we give an overview of the myeloid-derived suppressor cells field focusing primarily on the studies in cancer patients and current and future therapeutic options targeting these cells.

Coronatine (COR), a jasmonate mimic produced by Pseudomonas syringae pv. tomato DC3000 (Pst DC3000) is required for full virulence of Pst DC3000 in tomato and Arabidopsis. COR is shown to induce a range of physiological processes including chlorosis, root growth inhibition and anthocyanin accumulation in tomato. To elucidate the host/signaling genes involved in COR-responses, we utilized a forward genetics approach using Nicotiana benthamiana and virus-induced gene silencing (VIGS) and identified genes that play a role in COR-mediated chlorosis. We designated these genes as altered COR response (ALC). When silenced, one gene designated ALC1 produced a hypersensitive/necrosis-like phenotype after COR application in a coronatine insensitive 1 (COI1)-dependent manner. In pathogenicity assays performed on Arabidopsis thylakoid formation 1 (thf1) knockout lines and SlALC1-silenced tomato plants, Pst DC3000 induced coalescing necrotic lesions in an accelerated manner. Furthermore, we showed that COR affects ALC1 localization in chloroplast in a COI1-dependent manner. In conclusion, our results show the potential of VIGS-based, forward genetic screens to identify new players in COR-mediated signal transduction.

Cancer immunotherapy faces a serious challenge because of low clinical efficacy. Recently, a number of clinical studies have reported the serendipitous finding of high rates of objective clinical response when cancer vaccines are combined with chemotherapy in patients with different types of cancers. However, the mechanism of this phenomenon remains unclear. Here, we tested in mice several cancer vaccines and an adoptive T cell transfer approach to cancer immunotherapy in combination with several widely used chemotherapeutic drugs. We found that chemotherapy made tumor cells more susceptible to the cytotoxic effect of CTLs through a dramatic perforin-independent increase in permeability to GrzB released by the CTLs. This effect was mediated via upregulation of mannose-6-phosphate receptors on the surface of tumor cells and was observed in mouse and human cells. When combined with chemotherapy, CTLs raised against specific antigens were able to induce apoptosis in neighboring tumor cells that did not express those antigens. These data suggest that small numbers of CTLs could mediate a potent antitumor effect when combined with chemotherapy. In addition, these results provide a strong rationale for combining these modalities for the treatment of patients with advanced cancers.

Purpose: Myeloid-derived suppressor cells (MDSC) are one of the major factors responsible for immune suppression in cancer. Therefore, it would be important to identify effective therapeutic means to modulate these cells., Experimental Design: We evaluated the effect of the synthetic triterpenoid C-28 methyl ester of 2-cyano-3,12-dioxooleana-1,9,-dien-28-oic acid (CDDO-Me; bardoxolone methyl) in MC38 colon carcinoma, Lewis lung carcinoma, and EL-4 thymoma mouse tumor models, as well as blood samples from patients with renal cell cancer and soft tissue sarcoma. Samples were also analyzed from patients with pancreatic cancer treated with CDDO-Me in combination with gemcitabine., Results: CDDO-Me at concentrations of 25 to 100 nmol/L completely abrogated immune suppressive activity of MDSC in vitro. CDDO-Me reduced reactive oxygen species in MDSCs but did not affect their viability or the levels of nitric oxide and arginase. Treatment of tumor-bearing mice with CDDO-Me did not affect the proportion of MDSCs in the spleens but eliminated their suppressive activity. This effect was independent of antitumor activity. CDDO-Me treatment decreased tumor growth in mice. Experiments with severe combined immunodeficient-beige mice indicated that this effect was largely mediated by the immune system. CDDO-Me substantially enhanced the antitumor effect of a cancer vaccines. Treatment of pancreatic cancer patients with CDDO-Me did not affect the number of MDSCs in peripheral blood but significantly improved the immune response., Conclusions: CDDO-Me abrogated the immune suppressive effect of MDSCs and improved immune responses in tumor-bearing mice and cancer patients. It may represent an attractive therapeutic option by enhancing the effect of cancer immunotherapy.

Ag-specific T cell tolerance plays a critical role in tumor escape. Recent studies implicated myeloid-derived suppressor cells (MDSCs) in the induction of CD8(+) T cell tolerance in tumor-bearing hosts. However, the mechanism of this phenomenon remained unclear. We have found that incubation of Ag-specific CD8(+) T cells, with peptide-loaded MDSCs, did not induce signaling downstream of TCR. However, it prevented subsequent signaling from peptide-loaded dendritic cells. Using double TCR transgenic CD8(+) T cells, we have demonstrated that MDSC induced tolerance to only the peptide, which was presented by MDSCs. T cell response to the peptide specific to the other TCR was not affected. Incubation of MDSCs with Ag-specific CD8(+) T cells caused nitration of the molecules on the surface of CD8(+) T cells, localized to the site of physical interaction between MDSC and T cells, which involves preferentially only TCR specific for the peptide presented by MDSCs. Postincubation with MDSCs, only nitrotyrosine-positive CD8(+) T cells demonstrated profound nonresponsiveness to the specific peptide, whereas nitrotyrosine-negative CD8(+) T cells responded normally to that stimulation. MDSCs caused dissociation between TCR and CD3zeta molecules, disrupting TCR complexes on T cells. Thus, these data describe a novel mechanism of Ag-specific CD8(+) T cell tolerance in cancer.

Synthesis of enone core based dendrimers with carbazole as surface group has been achieved. All the synthesized dendrimers showed excellent antioxidant behavior with commercially available 1,1-diphenyl-2-picryl hydrazyl (DPPH)., (Copyright (c) 2009 Elsevier Masson SAS. All rights reserved.)

Pseudomonas syringae pv tomato DC3000 (Pst DC3000), which causes disease in tomato (Solanum lycopersicum) and Arabidopsis (Arabidopsis thaliana), produces coronatine (COR), a non-host-specific phytotoxin. COR, which functions as a jasmonate mimic, is required for full virulence of Pst DC3000 and for the induction of chlorosis in host plants. Previous genetic screens based on insensitivity to COR and/or methyl jasmonate identified several potential targets for COR and methyl jasmonate. In this study, we utilized Nicotiana benthamiana and virus-induced gene silencing to individually reduce the expression of over 4,000 genes. The silenced lines of N. benthamiana were then screened for altered responses to purified COR. Using this forward genetics approach, several genes were identified with altered responses to COR. These were designated as ALC (for altered COR response) genes. When silenced, one of the identified genes, ALC1, produced a hypersensitive/necrosis-like phenotype upon COR application in a Coronatine-Insensitive1 (COI1)-dependent manner. To understand the involvement of ALC1 during the Pst DC3000-host interaction, we used the nucleotide sequence of ALC1 and identified its ortholog in Arabidopsis (Thylakoid Formation1 [THF1]) and tomato (SlALC1). In pathogenicity assays performed on Arabidopsis thf1 mutant and SlALC1-silenced tomato plants, Pst DC3000 induced accelerated coalescing necrotic lesions. Furthermore, we showed that COR affects ALC1 localization in chloroplasts in a COI1-dependent manner. In conclusion, our results show that the virus-induced gene silencing-based forward genetic screen has the potential to identify new players in COR signaling and disease-associated necrotic cell death.

Fatty acid amide hydrolase (FAAH) terminates the endocannabinoid signaling pathway that regulates numerous neurobehavioral processes in animals by hydrolyzing N-acylethanolamines (NAEs). Recently, an Arabidopsis FAAH homologue (AtFAAH) was identified, and several studies, especially those using AtFAAH overexpressing and knock-out lines, have suggested an in vivo role for FAAH in the catabolism of NAEs in plants. We previously reported that overexpression of AtFAAH in Arabidopsis resulted in accelerated seedling growth, and in seedlings that were insensitive to exogenous NAEs but hypersensitive to abscisic acid (ABA) and hypersusceptible to nonhost pathogens. Here we show that whereas the enhanced growth and NAE tolerance of the AtFAAH overexpressing seedlings depend on the catalytic activity of AtFAAH, hypersensitivity to ABA and hypersusceptibility to nonhost pathogens are independent of its enzymatic activity. Five amino acids known to be critical for rat FAAH activity are also conserved in AtFAAH (Lys-205, Ser-281, Ser-282, Ser-305, and Arg-307). Site-directed mutation of each of these conserved residues in AtFAAH abolished its hydrolytic activity when expressed in Escherichia coli, supporting a common catalytic mechanism in animal and plant FAAH enzymes. Overexpression of these inactive AtFAAH mutants in Arabidopsis showed no growth enhancement and no NAE tolerance, but still rendered the seedlings hypersensitive to ABA and hypersusceptible to nonhost pathogens to a degree similar to the overexpression of the native AtFAAH. Taken together, our findings suggest that the AtFAAH influences plant growth and interacts with ABA signaling and plant defense through distinctly different mechanisms.

Obestatin is a twenty three amino acid peptide produced in the stomach by post translational modification of the preproghrelin gene. Since its discovery in 2005, many studies have shown that obestatin reduces feed intake and gain in body weight in rodents. Studies from our laboratory have shown the N-terminal thirteen residues mimic obestatin the best and residues 6-18 reduce epididymal fat significantly in adult male mice. In this study we have tried to increase the efficacy of these fragments. As an initial step, we have substituted G(8) with alpha-aminoisobutyricacid(Aib,U) and F(5) with cyclohexylalanine(Cha) in the N-terminal peptide to obtain two modified peptides and modified the middle fragment (residues 6-18) by substituting both the glycine residues at position 3 and 8 with alpha-aminoisobutyricacid(U). The rationale being, unusual amino acids could protect the peptides from immediate degradation and Aib would also induce secondary structure in these unstructured peptides. The N-terminal fragment with the G(8)U substitution fared the best. It reduced food intake, gain in body weight, levels of cholesterol and triglycerides in the blood, epididymal and perirenal fat in adult male mice similar to that of obestatin. The middle fragment with G(3,8)U double substitution was the second best.

As an initial effort to identify opportunities to improve the management of children with nephrotic syndrome, the goal of this study was to assess the present-day management of children with primary nephrotic syndrome. A web-based survey was designed to assess the current management styles of all pediatric nephrology faculties at ten participating institutions. Ninety-one percent completed the initial survey. The duration of initial glucocorticoid therapy ranged from 4 to 24 weeks. Physicians reported that the recommendation for kidney biopsy was dependent on the response to initial corticosteroid therapy, with the minority always recommending a biopsy for frequently relapsing or steroid-dependent cases. All responding physicians recommended a kidney biopsy in steroid-resistant cases. Treatment strategies were reported to vary based upon the steroid response pattern and, where available, kidney histopathology. Striking variations in therapeutic preferences were described when alternatives to glucocorticoids were considered. The variability of management practices among pediatric nephrologists in the USA combined with the changing characteristics of our pediatric population raise concerns about our future strategies for improving healthcare for children coping with nephrotic syndrome. This variability is not unique to children's healthcare or to nephrology. However, a systematic approach to patient care and improvement in health outcomes has been shown to substantially improve morbidity and mortality outcomes in children with chronic health conditions.

The therapeutic approach to childhood nephrotic syndrome is based on a series of studies that began with an international collaborative effort sponsored by the International Study of Kidney Disease in Children in 1967. The characteristics of children presenting with nephrotic syndrome have changed over recent decades with greater frequency of the challenging condition focal segmental glomerulosclerosis and a greater prevalence of obesity and diabetes mellitus, which may be resistant to glucocorticoids in the former and exacerbated by long-term glucocorticoid therapy in the latter 2 conditions. The Children's Nephrotic Syndrome Consensus Conference was formed to systematically review the published literature and generate a children's primary nephrotic syndrome guideline for use in educational, therapeutic, and research venues.

Synthesis of novel quinoline based dicationic benzimidazolophanes and imidazolophanes incorporating various spacer units is described. Some of the quinolinophanes 1b, 3a,3b and 4a exhibit good antibacterial activity against most of the human pathogenic bacteria in the tested concentrations as compared to the other cyclophanes as well as the test control, streptomycin.

Large conductance calcium-activated potassium (BK) channels are very prominently expressed in adrenal chromaffin and many anterior pituitary cells, where they shape intrinsic excitability complexly. Stress- and sex-steroids regulate alternative splicing of Slo-alpha, the pore-forming subunit of BK channels, and chronic behavioural stress has been shown to alter Slo splicing in tree shrew adrenals. In the present study, we focus on mice, measuring the effects of chronic behavioural stress on total mRNA expression of the Slo-alpha gene, two key BK channel beta subunit genes (beta2 and beta4), and the 'STREX' splice variant of Slo-alpha. As a chronic stressor, males of the relatively aggressive SJL strain were housed with a different unfamiliar SJL male every 24 h for 19 days. This 'social-instability' paradigm stressed all individuals, as demonstrated by reduced weight gain and elevated corticosterone levels. Five quantitative reverse transcriptase-polymerase chain assays were performed in parallel, including beta-actin, each calibrated against a dilution series of its corresponding cDNA template. Stress-related changes in BK expression were larger in mice tested at 6 weeks than 9 weeks. In younger animals, Slo-alpha mRNA levels were elevated 44% and 116% in the adrenal medulla and pituitary, respectively, compared to individually-housed controls. beta2 and beta4 mRNAs were elevated 162% and 194% in the pituitary, but slightly reduced in the adrenals of stressed animals. In the pituitary, dominance scores of stressed animals correlated negatively with alpha and beta subunit expression, with more subordinate individuals exhibiting levels that were three- to four-fold higher than controls or dominant individuals. STREX variant representation was lower in the subordinate subset. Thus, the combination of subunits responding to stress differs markedly between adrenal and pituitary glands. These data suggest that early stress will differentially affect neuroendocrine cell excitability, and call for detailed analysis of functional consequences.

Myeloid-derived suppressor cells (MDSCs) are a heterogeneous population of cells that expand during cancer, inflammation and infection, and that have a remarkable ability to suppress T-cell responses. These cells constitute a unique component of the immune system that regulates immune responses in healthy individuals and in the context of various diseases. In this Review, we discuss the origin, mechanisms of expansion and suppressive functions of MDSCs, as well as the potential to target these cells for therapeutic benefit.

The Diagnosis and Staging Working Group of the NIH Consensus Development Project on Criteria for Clinical Trials in chronic GVHD (CGVHD) recently proposed criteria for diagnosis and assessment of overall CGVHD severity. We retrospectively reviewed 54 consecutive patients diagnosed with CGVHD between January 2002 and December 2005 after sibling donor transplant to assess the applicability of the new criteria in prognosticating survival and transplant-related mortality (TRM). A total of 8 patients (15%) were reclassified as late onset/persistent or recurrent acute GVHD (late aGVHD), 15 (28%) had overlap syndrome and 31 (57%) had classic CGVHD. Three-year overall survival was worse in patients with late aGVHD (3-year probability 25% (95% CI 4-56%)) followed by overlap syndrome (3-year probability 87% (95% CI 56-96%)) and CGVHD (3-year probability 75% (95% CI 54-87%)); P=0.001. Among patients with overlap syndrome and CGVHD, a trend towards worse survival was seen in patients with severe disease (3-year probability 57.3% (95% CI 21-82%)) as compared to mild+moderate disease (3-year probability 85.1% (95% CI 68-94)); P=0.1. This analysis, undertaken in a contemporary cohort of related donor recipients, indicates that the consensus guidelines are applicable to this population of CGVHD patients.

Myeloid-derived suppressor cells (MDSC) are a heterogeneous group of cells that play a critical role in tumor associated immune suppression. In an attempt to identify a specific subset of MDSC primarily responsible for immunosuppressive features of these cells, 10 different tumor models were investigated. All models showed variable but significant increase in the population of MDSC. Variability of MDSC expansion in vivo matched closely the effect of tumor cell condition medium in vitro. MDSC consists of two major subsets of Ly6G(+)Ly6C(low) granulocytic and Ly6G(-)Ly6C(high) monocytic cells. Granulocytic MDSC have increased level of reactive oxygen species and undetectable level of NO whereas monocytic MDSC had increased level of NO but undetectable levels of reactive oxygen species. However, their suppressive activity per cell basis was comparable. Almost all tumor models demonstrated a preferential expansion of granulocytic subset of MDSC. We performed a phenotypical and functional analysis of several surface molecules previously suggested to be involved in MDSC-mediated suppression of T cells: CD115, CD124, CD80, PD-L1, and PD-L2. Although substantial proportion of MDSC expressed those molecules no differences in the level of their expression or the proportion, positive cells were found between MDSC and cells from tumor-free mice that lack immune suppressive activity. The level of MDSC-mediated T cell suppression did not depend on the expression of these molecules. These data indicate that suppressive features of MDSC is caused not by expansion of a specific subset but more likely represent a functional state of these cells.

Objectives: The major histocompatibility complex class II chaperone invariant chain (Ii) is widely used as a carrier for inserted antigenic sequences and their introduction into the class II processing pathway. The tumor-associated antigen core 2beta 1,6 N-acetylglucosaminyltransferase (C2GnT), a glycosyltransferase present in human pancreatic tumor cells, is not expressed by normal pancreatic tissues., Methods: A set of expression vectors was engineered where the class II binding region of Ii was replaced by C2GnT-derived sequences. We investigated in vitro whether dendritic cells transfected with Ii-C2GnT constructs were capable to stimulate proliferation of CD4 T cells. We also tested whether vaccination with Ii-C2GnT would protect mice from tumor development., Results: Invariant chain-C2GnT fusion proteins bind to human DR1, DR3, DR4 and to mouse I-A molecules. Our results demonstrate that the plasmid DNA encoding the C2GnT epitope embedded in Ii induces tumor-specific T-cell responses. Mice immunized with the Ii constructs showed reduced growth of Panc02 pancreatic tumor cells., Conclusions: Therefore, Ii clipped with the tumor-associated antigen C2GnT shows promise for the treatment of pancreatic cancer.

Accumulation of myeloid-derived suppressor cells (MDSCs) associated with inhibition of dendritic cell (DC) differentiation is one of the major immunological abnormalities in cancer and leads to suppression of antitumor immune responses. The molecular mechanism of this phenomenon remains unclear. We report here that STAT3-inducible up-regulation of the myeloid-related protein S100A9 enhances MDSC production in cancer. Mice lacking this protein mounted potent antitumor immune responses and rejected implanted tumors. This effect was reversed by administration of wild-type MDSCs from tumor-bearing mice to S100A9-null mice. Overexpression of S100A9 in cultured embryonic stem cells or transgenic mice inhibited the differentiation of DCs and macrophages and induced accumulation of MDSCs. This study demonstrates that tumor-induced up-regulation of S100A9 protein is critically important for accumulation of MDSCs and reveals a novel molecular mechanism of immunological abnormalities in cancer.

Septins are a conserved family of eukaryotic GTP-binding, filament-forming proteins. In Saccharomyces cerevisiae, five septins (Cdc3p, Cdc10p, Cdc11p, Cdc12p, and Shs1p) form a complex and colocalize to the incipient bud site and as a collar of filaments at the neck of budded cells. Septins serve as a scaffold to localize septin-associated proteins involved in diverse processes and as a barrier to diffusion of membrane-associated proteins. Little is known about the role of nucleotide binding in septin function. Here, we show that Cdc3p, Cdc10p, Cdc11p, and Cdc12p all bind GTP and that P-loop and G4 motif mutations affect nucleotide binding and result in temperature-sensitive defects in septin localization and function. Two-hybrid, in vitro, and in vivo analyses show that for all four septins nucleotide binding is important in septin-septin interactions and complex formation. In the absence of complete complexes, septins do not localize to the cortex, suggesting septin localization factors interact only with complete complexes. When both complete and partial complexes are present, septins localize to the cortex but do not form a collar, perhaps because of an inability to form filaments. We find no evidence that nucleotide binding is specifically involved in the interaction of septins with septin-associated proteins.

Objective: Early compartment syndrome is difficult to diagnose, and a delay in the diagnosis can result in amputation or death. Our objective was to explore the potential of infrared imaging, a portable and noninvasive technology, for detecting compartment syndrome in the legs of patients with multiple trauma. We hypothesized that development of compartment syndrome is associated with a reduction in surface temperature in the involved leg and that the temperature reduction can be detected by infrared imaging., Design: Observational clinical study., Setting: Level I trauma center between July 2006 and July 2007., Patients: Trauma patients presenting to the emergency department., Interventions: Average temperature of the anterior surface of the proximal and distal region of each leg was measured in the emergency department with a radiometrically calibrated, 320 x 240, uncooled microbolometer infrared camera., Measurements and Main Results: The difference in surface temperature between the thigh and foot regions (thigh-foot index) of the legs in trauma patients was determined by investigators blinded to injury pattern using thermographic image analysis software. The diagnosis of compartment syndrome was made intraoperatively. Thermographic images from 164 patients were analyzed. Eleven patients developed compartment syndrome, and four of those patients had bilateral compartment syndrome. Legs that developed compartment syndrome had a greater difference in proximal vs. distal surface temperature (8.80 +/- 2.05 degrees C) vs. legs without compartment syndrome (1.22 +/- 0.88 degrees C) (analysis of variance p < .01). Patients who developed unilateral compartment syndrome had a greater proximal vs. distal temperature difference in the leg with (8.57 +/- 2.37 degrees C) vs. the contralateral leg without (1.80 +/- 1.60 degrees C) development of compartment syndrome (analysis of variance p < .01)., Conclusions: Infrared imaging detected a difference in surface temperature between the proximal and distal leg of patients who developed compartment syndrome. This technology holds promise as a supportive tool for the early detection of acute compartment syndrome in trauma patients.

T-cell nonresponsiveness is a critical factor in immune escape and myeloid-derived suppressor cells play a major role in organizing this phenomenon. Recent findings indicate that myeloid-derived suppressor cells can induce antigen-specific CD8(+) T-cell tolerance through a posttranslation mechanism which involves modification (nitration) of CD8 and the T-cell receptor itself on the T-cell surface. Elucidation of this mechanism of T-cell tolerance offers new opportunities for therapeutic corrections of immune escape in cancer.

Objectives: Orthotopic tumor models are regarded as being suitable for preclinical research on pancreatic cancer. The anatomic localization of the tumor in the retroperitoneum, however, provides little possibility for monitoring tumor growth., Methods: To assess time-related changes in orthotopic tumor volume, we applied transabdominal high-resolution compound imaging to the murine pancreas. A 15-MHz ultrasound probe was used to determine the feasibility of real-time transabdominal high-resolution ultrasonography to initiate tumor growth by inoculation of pancreatic tumor cells into the pancreas and monitor tumor growth, as well as use as a tool for assessing response to chemotherapy., Results: High-resolution ultrasound allows for precise tumor inoculation in the pancreas. Sonographic-evaluated tumor weight was found to be closely related to actual tumor weight (R = 0.97) measured during necropsy., Conclusions: High-resolution real-time compound imaging substitutes killing of mice during longitudinal studies and can be used for minimizing animal consumption because each mouse can be followed in an experimental group rather than having to resort to euthanasia for tissue harvesting.

Obestatin, shown to reduce feed intake and gain in body weight in rodents, is a very attractive candidate to be used against obesity. In this study, we aimed to investigate the relationship between the primary structure and activity of obestatin. Also of interest to us is a peptide of minimal length that closely mimics obestatin. Towards the same, we synthesized rodent obestatin and three overlapping fragments spanning residues 1-13, 6-18, and 11-23 of obestatin. These peptides subsequent to purification and characterization were tested upon adult male mice for their ability to reduce feed intake and gain in body weight. The N-terminal peptide (residues 1-13) mimicked obestatin the closest. The middle fragment (residues 6-18) significantly reduced epididymal fat without much altering feed intake or body weight.

Aim: To estimate the cost of an episode of inpatient care and the economic burden of hospitalisation for childhood rotavirus gastroenteritis (GE) in Malaysia., Methods: A 12-month prospective, hospital-based study on children less than 14 years of age with rotavirus GE, admitted to University of Malaya Medical Centre, Kuala Lumpur, was conducted in 2002. Data on human resource expenditure, costs of investigations, treatment and consumables were collected. Published estimates on rotavirus disease incidence in Malaysia were searched. Economic burden of hospital care for rotavirus GE in Malaysia was estimated by multiplying the cost of each episode of hospital admission for rotavirus GE with national rotavirus incidence in Malaysia., Results: In 2002, the per capita health expenditure by Malaysian Government was US$71.47. Rotavirus was positive in 85 (22%) of the 393 patients with acute GE admitted during the study period. The median cost of providing inpatient care for an episode of rotavirus GE was US$211.91 (range US$68.50-880.60). The estimated average cases of children hospitalised for rotavirus GE in Malaysia (1999-2000) was 8571 annually. The financial burden of providing inpatient care for rotavirus GE in Malaysian children was estimated to be US$1.8 million (range US$0.6 million-7.5 million) annually., Conclusion: The cost of providing inpatient care for childhood rotavirus GE in Malaysia was estimated to be US$1.8 million annually. The financial burden of rotavirus disease would be higher if cost of outpatient visits, non-medical and societal costs are included.

We present a comparative analysis of clinical presentation and response to treatment in 170 patients with chronic graft versus host disease (cGVHD) (123 following transplant from an unrelated donor [URD] and 47 from umbilical cord blood [UCB]). URD transplant recipients were significantly younger (median age 25 versus 39 years, P = .002; and the donor grafts were mostly HLA matched (67% versus 10%, P < .0001). UCB recipients had more frequent responses (complete remission [CR] + partial remission [PR]) to treatment (URD 48% versus UCB 74% at 2 months [P = .005]; 49% versus 78% at 6 months [P = .001] and 51% versus 72% at 1 year [P = .03] in the URD and UCB groups, respectively). Nonrelapse mortality (NRM) after diagnosis of cGVHD was worse after URD grafts. (1 year NRM 27% [19%-35%] URD versus 11% [2%-20%] UCB, P = .055). Separate multivariate analyses were performed in each cohort. In both, thrombocytopenia and no CR or PR at 2 months were independently associated with increased mortality. In addition, progressive onset of cGVHD was a significant predictor of increased mortality in URD cohort. These data suggest that cGVHD following UCB transplant may be more responsive to therapy and also lead to a lower NRM.

Antigen-specific CD8+ T-cell tolerance, induced by myeloid-derived suppressor cells (MDSCs), is one of the main mechanisms of tumor escape. Using in vivo models, we show here that MDSCs directly disrupt the binding of specific peptide-major histocompatibility complex (pMHC) dimers to CD8-expressing T cells through nitration of tyrosines in a T-cell receptor (TCR)-CD8 complex. This process makes CD8-expressing T cells unable to bind pMHC and to respond to the specific peptide, although they retain their ability to respond to nonspecific stimulation. Nitration of TCR-CD8 is induced by MDSCs through hyperproduction of reactive oxygen species and peroxynitrite during direct cell-cell contact. Molecular modeling suggests specific sites of nitration that might affect the conformational flexibility of TCR-CD8 and its interaction with pMHC. These data identify a previously unknown mechanism of T-cell tolerance in cancer that is also pertinent to many pathological conditions associated with accumulation of MDSCs.

Polymicrobial sepsis alters the adaptive immune response and induces T cell suppression and Th2 immune polarization. We identify a GR-1(+)CD11b(+) population whose numbers dramatically increase and remain elevated in the spleen, lymph nodes, and bone marrow during polymicrobial sepsis. Phenotypically, these cells are heterogeneous, immature, predominantly myeloid progenitors that express interleukin 10 and several other cytokines and chemokines. Splenic GR-1(+) cells effectively suppress antigen-specific CD8(+) T cell interferon (IFN) gamma production but only modestly suppress antigen-specific and nonspecific CD4(+) T cell proliferation. GR-1(+) cell depletion in vivo prevents both the sepsis-induced augmentation of Th2 cell-dependent and depression of Th1 cell-dependent antibody production. Signaling through MyD88, but not Toll-like receptor 4, TIR domain-containing adaptor-inducing IFN-beta, or the IFN-alpha/beta receptor, is required for complete GR-1(+)CD11b(+) expansion. GR-1(+)CD11b(+) cells contribute to sepsis-induced T cell suppression and preferential Th2 polarization.

Survivin is a good candidate for cancer immunotherapy since it is overexpressed in most common human cancers, poorly expressed in most normal adult tissues and is essential for cancer cell survival. Previously, we and others have demonstrated that survivin-specific immune responses can be generated in mice and cancer patients. These responses resulted in a substantial antitumor effect. However, the fact that survivin is expressed in normal hematopoietic progenitor cells and endothelial cells may potentially limit the use of vaccination against survivin in the clinic due to possible toxicity. In this study, we have evaluated this risk by using dendritic cells (DC) transduced with an adenovirus encoding mutant human survivin (Ad-surv DCs). Immunization of mice with Ad-surv DCs resulted in generation of CD8 T cells recognizing multiple epitopes from mouse survivin. These responses provided significant antitumor effect against 3 different tumors EL-4 lymphoma, MC-38 carcinoma, and MethA sarcoma. Survivin-specific T-cells did not affect bone marrow hematopoietic progenitor cells and no autoimmune abnormalities were observed. However, as was the case with other tumor vaccines it provided only partial antitumor effect against established tumors. The existing paradigm suggests that generation of immune response against multiple tumor-associated antigens may provide a better antitumor effect. Here, we directly tested this hypothesis by combining vaccines targeting different tumor-associated proteins: survivin and p53. Despite the fact that combination of 2 vaccines generated potent antigen specific T-cell responses against both molecules they did not result in the improvement of antitumor effect in any of the tested experimental tumor models.

The development of tumor-specific T cell tolerance is largely responsible for tumor escape. Accumulation of myeloid-derived suppressor cells (MDSCs) in animal tumor models as well as in cancer patients is involved in tumor-associated T cell tolerance. In recent years, it has become increasingly evident that MDSCs bring about antigen-specific T cell tolerance by various mechanisms, which is the focus of this chapter.