Increased levels of microbial substances may, at least in part, contribute

to the ‘farm effect’. However, only few studies have measured microbial exposures in these environments and the results obtained so far suggest LEE011 in vitro that the underlying protective microbial exposure(s) have not been identified, but a number of studies using metagenomic approaches are currently under way. The mechanisms by which such environmental exposures confer protection from respiratory allergies are also not well understood. There is good evidence for the involvement of innate immune responses, but translation into protective mechanisms for asthma and allergies is lacking. Furthermore, a number of gene × environment interactions have been observed. In recent years, the ‘hygiene hypothesis’ has received much attention [1]. This field of allergy research investigates the potential link between exposure to microbial sources and the development of allergic and autoimmune diseases. At least three distinct claims on the underlying nature of the hygiene hypothesis

have been brought forward. First, the potential role of overt and unapparent infections with viruses and bacteria has been discussed; secondly, the PFT�� relevance of non-invasive microbial exposures in the environment has been shown to influence the development of allergic and also autoimmune diseases; and thirdly, the influence of such exposures and infections on a subject’s innate and adaptive immune response is being discussed. Before addressing these various aspects Masitinib (AB1010) of the hygiene hypothesis,

one must consider the complex nature of the problem. In clinical practice allergic illnesses may appear somewhat uniform because most patients present with a limited variety of symptoms, yet the underlying mechanisms and causes are likely to be numerous. Asthma and allergies are complex diseases determined by genetic variation interacting with environmental exposures. There is increasing evidence that it is not one single gene that causes, for example, asthma, but that many genes with small effects contribute to new-onset asthma. Moreover, several environmental determinants have been identified for different allergic illnesses which interact with an exposed subject’s genetic background. Furthermore, when considering the various environmental exposures and potential underlying mechanisms, one must bear in mind that the effect of an exposure has been shown to depend upon the timing. At least during infancy, childhood and adolescence the human organism is in a constant stage of development and maturation. These predefined processes display windows of accessibility and vulnerability to intrinsic and extrinsic influences only at certain stages of development. Most studies suggest that for asthma and allergies, early life, i.e.

Evidence supporting an enhanced consumption of long-chain n-3 PUFAs includes a study in which children with atopic eczema were found to have lower serum levels of EPA and DHA than non-atopic children, despite similar levels of fish consumption [2]. Results from intervention

studies have been inconclusive [13–15]. Various animal models have been used to study the role of n-3 PUFAs in atopic inflammation. Yokoyama et al. [16] showed a reduced atopic asthma reaction in a mouse model after exposure to aerosolized DHA. Yoshino and Ellis [17] reported a tendency towards reduced cell-mediated hypersensitivity reactions in mice fed a fish oil-supplemented diet. However, neither study Selleckchem Everolimus noted any effect on IgE production. Yet another study reported decreased secretion of Th1-type cytokines [IFN-γ and tumour necrosis factor (TNF)-α], but enhanced secretion of the Th2 cytokine IL-4, from splenocytes in mice fed a fish oil-enriched diet [18]. The present study

was designed to investigate EPZ015666 the hypothesis that intake of long-chain n-3 PUFAs would affect Th1- and Th2-mediated sensitization and/or inflammation differentially. The effects of fish oil (rich in n-3 PUFAs) and sunflower oil (rich in n-6 PUFAs) intake were studied in two mouse hypersensitivity models: Th1-driven delayed-type hypersensitivity (DTH) and Th2-driven IgE production and eosinophil-mediated airway inflammation. In addition, the effect of PUFA consumption on the fatty acid serum profile was evaluated by monitoring serum levels during the study. Four-week-old male BALB/c mice (Scanbur AB, Sollentuna, Sweden) were provided with food and water ad libitum. The mice were fed with one of three diets. The control group received regular

mouse chow containing 1 wt% soya oil (Lantmännen, Lidköping, Sweden). The fish oil group received regular chow supplemented with from 10 wt% fish oil containing 0·28 g EPA/ml and 0·34 g DHA/ml (Möllers Tran natural; Peter Möller, Oslo, Norway). The sunflower oil group received regular chow supplemented with 10 wt% sunflower oil containing 0·54 g linoleic acid/ml (Coop Solrosolja; Coop Sweden, Solna, Sweden). Permission for the study was granted by the Regional Ethics Committee, University of Gothenburg (no. 408-2008), and the experiments were carried out according to the guidelines of the ‘Council of Europe Convention for the Protection of Vertebrate Animals used for Experimental and Other Scientific purposes’. Th1-mediated hypersensitivity was tested in the DTH model summarized in Fig. 1a. After receiving the experimental or control diet for 21 days, the mice were anaesthetized briefly (Isofluran; Baxter Medical AB, Kista, Sweden) and then each hind leg was injected intramuscularly with 50 µg ovalbumin (OVA) in 50 µl of phosphate-buffered saline (PBS), emulsified in an equal volume of complete Freund’s adjuvant (Difco Laboratories, Detroit, MI, USA).

The receptor(s) responsible for induction of pathology remain to be determined, however, we found that the activating receptor NKp46 was low to negative on many cells expressing multiple NK-cell receptors in influenza-infected lung. Engagement of NKp46, presumably

by its ligand influenza HA [24] might be responsible Decitabine on its own or in combination with contributions by other activating NK-cell receptors for the activation of NK cells, leading to pathology. Alternatively, or in addition, NK cells can be activated by type I IFN released by DCs as a response to host infection by many diverse viruses [13], possibly serving as a stimulus for activated NK cell-mediated pathology. A feature of severe influenza infections in humans leading to mortality, including those by avian H5N1, is massive inflammation in the respiratory tract [41]. Infection of mice with H5N1 or the 1918 pandemic influenza virus [42, 43] results in excessive lung inflammation, as we observe here with high-dose A/PR8 strain infection. NK cells become activated and their BVD-523 supplier numbers reduce in peripheral blood, possibly due to entering the lung, when humans are exposed to seasonal or pandemic

strains of influenza [44]. NK cells may assist in orchestrating the excessive infiltration of lung by various cell types during severe influenza infections in addition to or instead of direct cytotoxic functions. High-dose A/PR8 infection in mice may serve as a model for severe influenza infections and the manipulation of NK cells for therapeutic benefit. Partial blocking of NKp46 interactions with influenza HA and/or modulation of Toll-like receptor interactions that lead to NK-cell activation

[45-47] may provide an appropriate balance of NK-cell responsiveness during severe influenza infections, such that they are sufficient to mediate protection but not excessive, resulting in pathology. Our report underscores the complexity of NK-cell influences during the host response to virus infection. Understanding the contributions of NK Exoribonuclease cells not only to host defense, but also toward pathology during virus infections will aid efforts at manipulation of NK cells for therapeutic efficacy. Female C57BL/6 mice at 6–8 weeks of age were purchased from Charles River Laboratories (Kingston, ON, Canada). Experiments were approved by the Animal Welfare and Policy Committee of the University of Alberta (Edmonton, AB, Canada). Housing and handling of mice was in accord with Canadian Council on Animal Care guidelines. Influenza A/PR8 virus was grown in eggs and HAU were determined by hemagglutination assay using chicken red blood cells (Lampire Biological Labs) [48]. For i.n.

Phagolysosome fusion was determined, as described previously [46]. Briefly, peritoneal macrophages were harvested and plated into eight-well chamber slides (Lab-Tek™, Nunc, Rochester, NY, USA) at 1 × 105 cells/well. After resting in RPMI1640 containing 1% FCS for 6 h, cells were loaded with 50 nM LysoTracker red (Molecular Probes) at 37°C for 30 min and further incubated with FITC-conjugated bacteria (Molecular Probes) of either S. aureus or E. coli (macrophage/bacteria = 1:20) for various time periods.

LysoTracker red was replenished every hour of incubation. After each time point, slides were vigorously washed five times in cold PBS and fixed in 2% paraformaldehyde (Sigma-Aldrich). Cell nuclei were stained with DAPI (Molecular Probes).

Slides were mounted with coverslips and examined under a fluorescent Olympus BX61-TRF microscope LY2835219 (Olympus, Tokyo, Japan). Fluorescent images check details were acquired using the cell imaging software for life sciences microscopy (Olympus Soft Imaging Solutions, Munster, Germany). Unfused phagosomes containing FITC-bacteria and lysosomes labeled with LysoTracker red were stained in green and red, respectively, whereas phagosomes containing FITC-bacteria after being fused with LysoTracker red-labeled lysosomes were stained in yellow due to the coexistence of the two fluorochromes. All data are expressed as the mean ± SD. Statistical analysis

was performed using the log rank test for survival and the Mann-Whitney U test for all others, with GraphPad software, version 5.01 (Prism, La Jolla, CA, USA). A p-value <0.05 was judged statistically significant. This work was supported by the National Natural Thalidomide Science Foundation of China (Grant 81272143), the Natural Science Foundation of Jiangsu Province (Grant K200509), Jiangsu Innovation Team (Grant LJ201141), Jiangsu Province Program of Innovative and Entrepreneurial Talents (2011–2014), and in part by the Science Foundation Ireland Research Frontiers Programme (Grant SFI/08/RFP/BIC1734). The authors declare no financial or commercial conflict of interest. “
“Endoscopic stenting is a palliative approach for the treatment of diseases involving biliary obstruction. Its major limitation is represented by stent occlusion, followed by life-threatening cholangitis, often requiring stent removal and replacement. Although it has been suggested that microbial colonization of biliary stents could play a role in the clogging process, the so far available data, particularly on the role of anaerobic bacteria, are not enough for a comprehensive description of this phenomenon.

27,28 The cells were used freshly for experiments or frozen in fetal calf serum (Sigma-Aldrich, Schelldorf, Germany) and 10% DMSO (Sigma-Aldrich), and stored at – 150°. Frozen PBMCs were thawed and rested overnight in medium at 37°. Cell viability was > 90%. Rhesus B cells were isolated by magnetic bead separation using CD20 microbeads

on an AutoMacs (Miltenyi Biotec, Bergisch Gladbach, Germany). Human PBMCs were obtained from healthy blood donors by collection of buffy coats. Human B cells were isolated from buffy coats by magnetic bead separation on an AutoMacs using CD19 microbeads (Miltenyi Biotec) as described previously.2,29 The purity was > 98% and > 85% for sorted human and rhesus B cells, respectively, as determined by staining for CD20 (clone 2H7), CD27 (clone M-T271), CD3 (clone SP34) and CD14 (clone TUK4) (all BD Pharmingen, San Jose, CA) (Fig. 1a). Propidium iodide staining (Sigma-Aldrich) JAK inhibitor was used to monitor cell Inhibitor Library viability. To determine the percentage of myeloid DCs (mDCs) and pDCs of the total PBMCs, rhesus PBMCs were stained with HLA-DR (clone L243), CD11c (clone S-HCL-3), CD123 (clone 7G3) (all BD Pharmingen) and the lineage markers CD3 (clone SP34), CD14 (clone TUK4) and CD20 (clone 2H7).

Human PBMCs were stained with the same antibody for HLA-DR, CD11c and CD123 and for the lineage markers CD3 (clone SK7), CD14 (clone TUK4), CD15 (clone MMA), CD19 (clone 4G7) and CD56 (clone NCAM16.2), (all BD Pharmingen). After 20 min, the cells were washed and resuspended in PBS containing 1% paraformaldehyde. The cells were analysed by flow cytometry (FACSCalibur, BD Biosciences) and data were evaluated using FlowJo software (Treestar Inc., San Carlos, CA). The mDCs and pDCs were identified as described.15 The phenotype of naive and memory B cells was characterized

as described3,27,30 using staining for CD27 (clone M-T271), IgG (clone G18-145) and IgM (clone G20-127) (all BD Pharmingen). For stimulation of cells, the following TLR ligands Alanine-glyoxylate transaminase were used; TLR3: the dsRNA complex polyinosinic : polycytidylic acid (poly(I : C), Sigma-Aldrich); TLR7/8: the imidazoquinoline compound (3M-012)31 referred to as TLR7/8-L (3M Pharmaceuticals, St. Paul, MN); TLR9: CpG ODN 2336 (CpG A), CpG ODN 10103 (CpG B); and CpG ODN 2395 (CpG C) (Coley Pharmaceutical Group, Ottawa, Canada).32 The contaminating endotoxin levels were ≤ 0·0125 ng/ml in all TLR ligands as measured using a Limulus amoebocyte lysate assay. Rhesus or human PBMCs were cultured at 1 × 106 to 2 × 106 cells/ml in 96-well plates or in polystyrene round-bottom tubes in complete medium (RPMI-1640 containing 10% fetal calf serum, 2 mm l-glutamine, 100 U/ml penicillin, 100 μm streptomycin (all from Sigma-Aldrich) and 1% HEPES (Gibco, Invitrogen, Carlsbad, CA).

The authors alone are responsible for the content and writing of the paper and declare no conflicts of interest. “
“Enterohemorrhagic Escherichia coli (EHEC) causes hemorrhagic colitis, and in more severe cases, a serious clinical complication

called hemolytic uremic syndrome (HUS). Shiga toxin (Stx)is one of the factors that cause HUS. Serotypes of Stx produced by EHEC include Stx1 and Stx2. Although some genetically mutated toxoids of Stx have been developed, large-scale preparation of Stx that is practical Proteases inhibitor for vaccine development has not been reported. Therefore, overexpression methods for Stx2 and mutant Stx2 (mStx2) in E. coli were developed. The expression plasmid pBSK-Stx2(His) was constructed by inserting the full-length Stx2 gene, in which a six-histidine tag gene was fused at the end of the B subunit into the lacZα fragment gene of the pBluescript II SK(+) vector. An E. coli MV1184 strain transformed with pBSK-Stx2(His) overexpressed histidine-tagged Stx2 (Stx2-His) in cells cultured in CAYE broth in the presence of lincomycin. Stx2-His was purified using TALON metal affinity resin followed by hydroxyapatite chromatography. From 1 L of culture, 68.8 mg of Stx2-His and 61.1 mg of mStx2-His, which was generated by site-directed

mutagenesis, were obtained. Stx2-His had a cytotoxic effect on HeLa cells and was lethal to mice. However, the toxicity of mStx2-His was approximately 1000-fold lower than that of Stx2-His. Mice immunized with SCH772984 mStx2-His produced specific antibodies that neutralized the toxicity of 3-oxoacyl-(acyl-carrier-protein) reductase Stx2 in HeLa cells. Moreover, these mice survived challenge with high doses of Stx2-His. Therefore, the lincomycin-inducible overexpression method is suitable for large-scale preparation of Stx2 vaccine antigens. Enterohemorrhagic Escherichia coli strains cause hemorrhagic colitis and a serious clinical complication called hemolytic uremic syndrome (HUS) that is characterized by hemolytic anemia, thrombocytopenia, and acute

renal failure [1, 2]. Major causative factors of EHEC include two types of Stx, Stx-1 and Stx-2 (also referred to as Vero toxin-1 and Vero toxin-2, respectively), both of which consist of one A subunit (Stx1A and Stx2A) and five B subunits (Stx1B and Stx2B). At the amino acid sequence level, Stx1 is almost identical to Stx produced by Shigella dysenteriae 1, whereas Stx2 shares only 55% and 61% amino acid sequence identity with Stx1 in the A and B subunits, respectively. The B subunits bind to Gb3 on the eukaryotic cell membrane [3-5], whereas the A subunit functions as an RNA N-glycosidase that cleaves off a single adenine in the 28S rRNA component of the 60S ribosomal subunit, leading to cell death by inhibition of protein synthesis [6, 7]. Stx2 toxicity is reportedly greater than that of Stx1, because in mice the LD50 of Stx2 is lower than that of Stx1 [8], and in humans Stx2-producing strains generate more severe symptoms than do other strains [9-11].

The MIC of FungisomeTM was two to 16-fold lower than AMB-d. These results reveal an efficient in vitro activity of FungisomeTM. “
“The aim of this study was to investigate the intraspecific diversity of Trichophyton rubrum clinical isolates. Thirty clinical isolates of T. rubrum were selected for molecular typing by PCR amplification of two tandemly repetitive

elements (TRS-1 and TRS-2) of the rDNA and randomly amplified polymorphic DNA (RAPD) analysis with primers designated 1 and 6. The assignment to the species T. rubrum was achieved by nested PCR of ITS1. Five PCR types were produced from the TRS-1 and three from the TRS-2 locus. Thirteen and 23 individual profiles were obtained by RAPD, with primer 1 and 6 respectively. At the phylogenetic level, compound screening assay 26 (87%) isolates were allocated into four clusters, with each cluster comprising isolates of over 80% similarity. The reproducibility of TRS typing was 100%, whereas that of RAPD

was 40% and 30%, when using primer 1 and 6 respectively. Neither correlation between the morphological characteristics and the TRS-1-TRS-2 or RAPD genotype nor between TRS-1-TRS-2 and RAPD genotyping was observed. Although both the TRS amplification and RAPD analysis possess the ability to discriminate between T. rubrum strains, the TRS typing method is particularly valuable as its results are much more reproducible, more easily interpreted and recorded than those generated Ulixertinib nmr by RAPD. “
“The aim of this study was to develop and validate a novel bioassay for determining serum voriconazole (VRC) concentrations and to compare its routine clinical performance with that of high-performance liquid chromatography (HPLC). The biological activity of VRC was measured by a plate diffusion assay using a VRC-hypersusceptible Candida kefyr strain. The bioassay’s utility was tested by measuring steady-state 2-hydroxyphytanoyl-CoA lyase VRC concentrations in 100 serum probes

from VRC-treated patients. The HPLC system used solvent extraction with hexane : dichloromethane followed by reversed-phase HPLC with ultraviolet detection. The intra-day and inter-day accuracy of the bioassay was <5%, while that of HPLC was <1%. The precision (mean coefficient of variation, 3.5%) was equal for both the methods. The limit of quantification was lower for HPLC (0.2 mg l−1) than for the bioassay (0.5 mg l−1). The result of linear regression analysis was HPLC = 1.0178 (bioassay) + 0.328; R2 = 0.88; n = 100. Results of the serum panel ranged from 0.5 to more than 8.0 mg l−1 for the bioassay and from 0.26 to 10.1 mg l−1 for HPLC. Especially in laboratories without access to HPLC, the bioassay may be a clinically useful tool for therapeutic drug monitoring. "
“Tinea capitis is a fungal infection of the hair follicles of the scalp. In the US, the most common organisms have traditionally been Trichophyton tonsurans, and occasionally Microsporum canis. This study was designed to examine patterns of organisms causing tinea capitis and determine factors associated with infection.

Animals.  C3H/HeN mice (Charles River Ltd, Margete, UK) 6–9 weeks of age of both genders were used in these studies. The animals were maintained at the animal premises of Ullevål University Hospital, Oslo, Norway. The experiments were approved by the Norwegian Ethics Committee for Animal Research and performed according to the NIH guidelines for selleck compound the use of experimental animals. Antigen. 

The hapten oxazolone (OXA, [4-ethoxymethalylene-2-phenyl-2-oxazolin-5-one]) was purchased from Sigma (St Louis, MO, USA). Sensitization and elicitation of CS.  Mice were sensitized and elicited according to a variation of an oral mucosa CS model [10]. Briefly, for sensitization 20 μl of 1% OXA in acetone/olive oil (1/10, v/v) was applied once on both sides of the ears or the inner face of the cheeks. One week later, animals were challenged with 10 μl of 1% OXA, topically applied onto both sides of both ears and on the mucosal surface of both cheeks with a total exposure of 60 μl. Sensitized and elicited as well as control mice exposed only once to the hapten were sacrificed at 0,

4, 6, 8, 12, 24, 48, 72 and 168 h after first or second hapten exposure in line with protocols published previously [8, 10]. The experimental series relating to cytokine measurements were performed thrice, and the graphs demonstrated represents typical results from one series of experiments. The experimental series demonstrating weight of lymph nodes and counting of lymph node cells (vide infra) are based upon 4–6 and two individual observations, ABT-737 cost respectively. Specimen treatment and ELISA analyses.  Buccal mucosa and ear skin as well as lymph nodes, i.e. regional (two submandibular and two auricular) and distant (four axillary) were excised from both sides of the mice. The buccal mucosa specimens were trimmed to a thin sheet of lamina propria and

epithelium. The ears were split along the cartilage, and specimens containing epidermis and dermis all were harvested. All specimens were weighed and immersed separately in 200 μl phosphate-buffered saline (PBS), pH 7.4. The PBS contained 1% bovine serum albumin, 0.5 m EDTA, 2% soy bean trypsin inhibitor and 2% phenylmethylsulphonylfluoride according to the method described by Villavedra et al. [20]. The specimens were frozen at −70 °C until further processed and analysed for cytokines. After thawing, saponin (2%) was added to the specimens and kept in cold (4 °C) overnight. After whirl mixing and centrifugation (1500 g for 5 min), the supernatants were collected and analysed with respect to IL-2 and IFN-γ, using BD™ OptEIA ELISA Sets (Pharmingen; BD™ Biosciences, San Diego, CA, USA). The biotinylated secondary Ab with streptavidin containing horse-radish peroxidase was developed by hydrogen peroxide and TMB (3, 3′, 5, 5′ tetramethylbenzidine). The reaction was stopped using 1 m sulphuric acid.

The transcriptional networks that maintain oxidant balance in the mature kidney provide promising entry points for future therapeutic interventions, including for CKD. The use of anti-oxidants targeted to specific pathways that are altered in CKD may prove beneficial, but it is likely that several anti-oxidants will be needed as a multi-drug therapy to target oxidant modifying pathways during the development of CKD. These include lipid peroxidation, which can be improved by α-tocopherol; glutathione redox regulation, which can be restored by NAC; uremic

toxins, which can be reduced by allopurinol; inflammation, which can be attenuated by ω-3 polyunsaturated fatty acids; and finally, mitochondrial dysfunction, which may be improved by CoQ10. Mosca and colleagues86 Talazoparib clinical trial found that healthy individuals taking a combination of α-tocopherol, α-lipoic acid, CoQ10, carnitines

and selenomethionine increased plasma anti-oxidant status, decreased lymphocyte HKI 272 apoptosis and decreased mitochondrial-derived ROS. In the CKD population, identification of patients who would benefit from anti-oxidant therapy is first needed, and then a multifaceted anti-oxidant approach may be necessary for successful treatment of CKD. “
“Aim:  There is little data on the prevalence and severity of dyslipidaemia in Asian patients with lupus nephritis (LN). Whether the dyslipidaemia in LN patients differs from subjects with comparable levels of renal impairment also remains undefined. Methods:  Lipid profiles of 100 Chinese patients with quiescent LN (age 46.3 ± 9.3 years, 83% female, maintenance prednisolone dose 5.80 ± 2.43 mg/day) were studied and compared with 100 controls who had non-lupus non-diabetic chronic kidney diseases (CKD), matched for sex, age and renal function. Results:  LN patients and CKD controls

had Amylase similar renal function and proteinuria, while blood pressure was higher in controls. Twenty-five percent of LN patients and 17% of controls were receiving statin treatment. Despite this, 59% of LN patients and 46% CKD controls showed abnormal lipid parameters (P = 0.066). LN patients showed higher levels of total cholesterol (TC) and triglycerides (TG) than controls (5.28 ± 0.12 vs 4.86 ± 0.08 mmol/L, P = 0.004; and 1.62 ± 0.12 vs 1.20 ± 0.07 mmol/L, P = 0.002, respectively). More LN patients had abnormal TC, TG or low-density lipoprotein cholesterol (LDL-C) (54%, 16% and 38%; P = 0.016, = 0.005 and = 0.021, respectively). Hydroxychloroquine (HCQ) treatment was associated with lower TC, LDL-C and HDL-cholesterol. Conclusion:  Dyslipidaemia is prevalent in LN patients and is more severe than controls with a similar degree of CKD despite disease quiescence, low steroid dose and low level of proteinuria. Concomitant corticosteroid and renal impairment are likely contributing factors. HCQ treatment is associated with reduced severity of dyslipidaemia in LN patients.

[45] There is also some suggestion that patients treated with MSC for their graft-versus-host leukaemia have an increased leukaemia relapse rate because of the impairment of graft-versus-leukaemia.[46] Further pathways mediating immune tolerance can be recruited and activated by MSC and one of the most important is the involvement of monocytes. There is plenty of evidence that MSC inhibit the differentiation of monocytes into dendritic cells and impair their ability to stimulate allogeneic T cells.[47-49] Of particular relevance is the demonstration that monocytes/macrophages are essential for the delivery of MSC-mediated immunosuppression.

The modalities of such interaction are several and diverse. The MSC induce dendritic cells to acquire a tolerogenic profile characterized by the up-regulation of IL-10 and the inhibition DNA Damage inhibitor of TNF-α and IFN-γ production.[47] Similarly, under particular conditions, MSC skew the inflammatory phenotype of macrophages by converting pro-inflammatory M1-type cells into a more anti-inflammatory M2-type subset.[50] When MSC are co-cultured with thioglycollate-elicited peritoneal macrophages in the presence of lipopolysaccharide, the production of the pro-inflammatory cytokines IFN-γ, TNF-α, IL-6 and IL-12p70 is markedly suppressed whereas the production of

both IL-12p40 and the anti-inflammatory cytokine IL-10 is increased.[51] A key role in the inflammatory switch is played JNK pathway inhibitor by prostaglandin E2 because cyclo-oxygenase-2 inhibitors negatively affect such MSC function. The effect of MSC on macrophages was confirmed in for vivo in at least two experimental systems. In one

case, MSC rendered macrophages highly susceptible to infection with Trypanosoma cruzi, increasing more than fivefold the rate of intracellular infection.[52] In another model, the beneficial effect of MSC on sepsis was associated with the recruitment of IL-10-producing macrophages.[50] MSC have been shown to recruit macrophages/monocytes and endothelial lineage cells into the inflammation site by releasing paracrine factors[53] and to inhibit the migration of neutrophils by modulating macrophage cytokine release.[50] The activity of MSC on monocytes/macrophages appears to be a fundamental component in MSC-mediated immunosuppression. It was initially observed that suppression of in vitro mitogen-induced T-cell proliferation by human MSC was profoundly impaired after the removal of monocytes in culture.[54] The prominent role of macrophages was similarly observed in vitro whereby macrophage depletion or pre-treatment with antibodies specific for IL-10 or IL-10 receptor reduced the therapeutic action on sepsis.[50] Macrophage polarization might account also for the tissue repair activity of MSC in a number of various conditions. In fact, it is well known that modulation of macrophages favours the conditions for a reparative state.