Modulation Of Cytokine Production Research Articles

Treatment of Virulent Mycobacterium tuberculosis and HIV Coinfected Macrophages with Gallium Nanoparticles Inhibits Pathogen Growth and Modulates Macrophage Cytokine Production.

Tuberculosis (TB), caused by Mycobacterium tuberculosis, remains a global threat. The course of TB is negatively impacted by coexistent infection with human immunodeficiency virus type 1 (HIV). Macrophage infection with these pathogens modulates their production of pro- and anti-inflammatory cytokines, which could play a crucial role in pathogenesis. Despite the important role of macrophages in containing infection by a variety of microbes, both HIV and M. tuberculosis infect and replicate within these cells during the course of HIV-M. tuberculosis coinfection. Both M. tuberculosis and HIV require iron for growth and replication. We have previously shown that gallium encapsulated in nanoparticles, which interferes with cellular iron acquisition and utilization, inhibited the growth of HIV and an attenuated strain of M. tuberculosis within human monocyte-derived macrophages (MDMs) in vitro Whether this was true for a fully virulent strain of M. tuberculosis and whether gallium treatment modulates cytokine production by HIV- and/or M. tuberculosis-infected macrophages have not been previously addressed. Therefore, coinfection of MDMs with HIV and a virulent M. tuberculosis strain (H37Rv) was studied in the presence of different gallium nanoparticles (GaNP). All GaNP were readily internalized by the MDMs, which provided sustained drug (gallium) release for 15 days. This led to significant growth inhibition of both HIV and M. tuberculosis within MDMs for up to 15 days after loading of the cells with all GaNP tested in our study. Cytokine analysis showed that HIV-M. tuberculosis coinfected macrophages secreted large amounts of interleukin 6 (IL-6) and IL-8 and smaller amounts of IL-1β, IL-4, and tumor necrosis factor alpha (TNF-α) cytokines. However, all GaNP were able to regulate the release of cytokines significantly. GaNP interrupts iron-mediated enzymatic reactions, leading to growth inhibition of HIV-M. tuberculosis coinfection in macrophages, and also modulates release of cytokines that may contribute to HIV-TB pathogenesis.IMPORTANCE GaNP interrupts iron-mediated enzymatic reactions, leading to growth inhibition of virulent HIV-M. tuberculosis coinfection in macrophages, and also modulates release of cytokines that may contribute to HIV-TB pathogenesis. Macrophage-targeting GaNP are a promising therapeutic approach to provide sustained antimicrobial activity against HIV-M. tuberculosis coinfection.

Cytokine Regulation from Human Peripheral Blood Leukocytes Cultured In Vitro with Silver Doped Bioactive Glasses Microparticles.

Bioactive glasses (BG) applications include tissue engineering for bone regeneration, coating for implants, and scaffolds for wound healing. BG can be conjugated to ions like silver, which might add some antimicrobial properties to this biomaterial. The immunomodulatory activity of ion-doped bioactive glasses particles was not investigated before. The aim of this work was to evaluate the cytotoxic and immunomodulatory effect of BG and silver-doped bioactive glass (BGAg) in human peripheral blood cells. BG and BGAg samples belonging to the system 58SiO2•(36-x)CaO·6P2O5·xAg2O, where x = 0 and 1 mol%, respectively, were synthesized via sol–gel method and characterized. Cytotoxicity, modulation of cytokine production (TNF-α, IL-1β, IL-6, IL-4, and IL-10), and oxidative stress response were investigated in human polymorphonuclear cells (PMNs) and peripheral blood mononuclear cells (PBMCs) cultures. Cell viability in the presence of BG or BGAg was concentration-dependent. In addition, BGAg presented higher PBMCs toxicity (LC50 = 0.005%) when compared to BG (LC50 = 0.106%). Interestingly, interleukin4 was produced by PBMCs in response to BG and BGAg in absence of phytohemagglutinin (PHA) and did not modulate PHA-induced cytokine levels. Subtoxic concentrations (0.031% for BG and 0.0008% for BGAg) did not change other cytokines in PBMCs nor reactive oxygen species (ROS) production by PMN. However, BG and BGAg particles decreased zymosan-induced ROS levels in PMN. Although ion incorporation increased BG cytotoxicity, the bioactive glass particles demonstrated a in vitro anti-inflammatory potencial. Future studies are needed to clarify the scavenger potential of the BG/BGAg particles/scaffolds as well as elucidate the effect of the anti-inflammatory potential in modulating tissue growth in vivo.

The cannabinoid receptor 2 agonist, β-caryophyllene, improves working memory and reduces circulating levels of specific proinflammatory cytokines in aged male mice

Age-related cognitive decline has been associated with proinflammatory cytokines, yet the precise relationship between cognitive decline and cytokine load remains to be elucidated. β-caryophyllene (BCP) is a cannabinoid receptor 2 (CB2) agonist with established anti-inflammatory effects that is known to improve memory and increase lifespan. It is of interest to explore the potential of BCP to reduce age-related cognitive decline and proinflammatory cytokine load. In this study, we assessed changes in circulating cytokines across the lifespan, memory performance in young and aged mice, and the effects of BCP on memory function and cytokine load. The plasma levels of 12 cytokines were assessed in male Swiss-Webster mice at 3, 12, and 18 months of age using multiplexed flow cytometry. Working memory was compared in 3 and 12 month-old mice using spontaneous alternations. A dose-response function (100–300 mg/kg, subchronic administration) for BCP-induced memory restoration was determined in 3- and 12- month-old mice. Finally, the effects on cytokine levels of the peak memory enhancing dose of BCP were assessed in 18- month-old mice. Circulating levels of several cytokines significantly increased with age. Multilinear regression analysis showed that IL-23 levels were most strongly associated with age. Aged mice showed deficits in working memory and higher levels of IL-23, both of which were reversed by BCP treatment. BCP appears to reverse age-associated impairments in memory and modulates cytokine production. IL-23 may play a significant role in the aging process, and future research should determine whether it has utility as a biomarker for novel anti-aging therapeutics.

Anti-inflammatory modulation of human myeloid-derived dendritic cell subsets by lenalidomide

Although immunomodulatory drugs (IMiDs) were originally developed as anti-inflammatory drugs, they are effective for multiple myeloma. In order to gain further insights into the immunomodulatory mechanisms of IMiDs for the treatment of inflammatory disorders and myeloma, we investigated the influence of a representative IMiD, lenalidomide, on human primary dendritic cell (DC) subsets: myeloid-derived CD1c+ DCs, CD141+ DCs, and plasmacytoid DCs. Lenalidomide did not affect the viability or expression of costimulatory molecules, but it potently suppressed the production of the key inflammatory cytokines IL-12 and IL-23, and enhanced the production of the anti-inflammatory cytokine IL-10 by CD1c+ DCs. Lenalidomide also suppressed the production of IFN-α by CD141+ DCs but not that by plasmacytoid DCs. Lenalidomide likely targets pathways downstream of the nuclear translocation of the transcription factors nuclear factor κB (NF-κB) and IFN regulatory 5 (IRF5) in CD1c+ DCs. Consistent with the direct immunomodulatory effects on DCs, lenalidomide decreased the capacity of CD1c+ DCs to induce differentiation of naïve CD4+ T cells into effector cells producing immune activating and myeloma-promoting cytokines. This study demonstrated that lenalidomide has anti-inflammatory effects via the modulation of cytokine production by human myeloid-derived DCs. Such effects on DCs may allow for beneficial immunomodulation aiding in the treatment of inflammatory disorders and multiple myeloma.

HIF-1α regulates IL-1β and IL-17 in sarcoidosis.

Sarcoidosis is a complex systemic granulomatous disease of unknown etiology characterized by the presence of activated macrophages and Th1/Th17 effector cells. Data mining of our RNA-Seq analysis of CD14+monocytes showed enrichment for metabolic and hypoxia inducible factor (HIF) pathways in sarcoidosis. Further investigation revealed that sarcoidosis macrophages and monocytes exhibit higher protein levels for HIF-α isoforms, HIF-1β, and their transcriptional co-activator p300 as well as glucose transporter 1 (Glut1). In situ hybridization of sarcoidosis granulomatous lung tissues showed abundance of HIF-1α in the center of granulomas. The abundance of HIF isoforms was mechanistically linked to elevated IL-1β and IL-17 since targeted down regulation of HIF-1α via short interfering RNA or a HIF-1α inhibitor decreased their production. Pharmacological intervention using chloroquine, a lysosomal inhibitor, decreased lysosomal associated protein 2 (LAMP2) and HIF-1α levels and modified cytokine production. These data suggest that increased activity of HIF-α isoforms regulate Th1/Th17 mediated inflammation in sarcoidosis.

Interleukin-10 Produced by Myeloid-Derived Suppressor Cells Provides Protection to Carbapenem-Resistant Klebsiella pneumoniae Sequence Type 258 by Enhancing Its Clearance in the Airways.

Carbapenem-resistant Klebsiella pneumoniae sequence type 258 (CRKP-ST258) can cause chronic infections in lungs and airways, with repeated episodes of bacteremia. In this report we addressed whether the recruitment of myeloid cells producing the anti-inflammatory cytokine interleukin-10 (IL-10) modulates the clearance of CKRP-ST258 in the lungs and establishes bacterial persistence. Our data demonstrate that during pneumonia caused by a clinical isolate of CRKP-ST258 (KP35) there is an early recruitment of monocyte-myeloid-derived suppressor cells (M-MDSCs) and neutrophils that actively produce IL-10. However, M-MDSCs were the cells that sustained the production of IL-10 over the time of infection evaluated. Using mice unable to produce IL-10 (IL-10-/-), we observed that the production of this cytokine during the infection caused by KP35 is important to control bacterial burden, to prevent lung damage, to modulate cytokine production, and to improve host survival. Importantly, intranasal transfer of bone marrow-derived M-MDSCs from mice able to produce IL-10 at 1 day prior to infection improved the ability of IL-10-/- mice to clear KP35 in the lungs, decreasing their mortality. Altogether, our data demonstrate that IL-10 produced by M-MDSCs is required for bacterial clearance, reduction of lung tissue damage, and host survival during KP35 pneumonia.

Ethyl Pyruvate Induces Tolerogenic Dendritic Cells.

Dendritic cells (DC) are professional antigen presenting cells that have a key role in shaping the immune response. Tolerogenic DC (tolDC) have immuno-regulatory properties and they are a promising prospective therapy for multiple sclerosis and other autoimmune diseases. Ethyl pyruvate (EP) is a redox analog of dimethyl fumarate (Tecfidera), a drug for multiple sclerosis treatment. We have recently shown that EP ameliorates experimental autoimmune encephalomyelitis, a multiple sclerosis murine model. Here, we expanded our study to its tolerogenic effects on DC. Phenotypic analysis has shown that DC obtained from mice or humans reduce expression of molecules required for T cell activation such as CD86, CD83, and HLA-DR under the influence of EP, while CD11c expression and viability of DC are not affected. Furthermore, EP-treated DC restrain proliferation and modulate cytokine production of allogeneic lymphocytes. These results demonstrate that EP has the ability to direct DC toward tolDC.

Bioimmunological activities of Candida glabrata cellular mannan.

Candida glabrata is a second most common human opportunistic pathogen which causes superficial but also life-threatening systemic candidosis. According to the localisation of mannans and mannoproteins in the outermost layer of the cell wall, mannan detection could be one of the first steps in the cell recognition of Candida cells by the host innate immune system. Mannans from the cell wall provide important immunomodulatory activities, comprising stimulation of cytokine production, induction of dendritic cells (DCs) maturation and T-cell immunity. The model of DCs represents a promising tool to study immunomodulatory interventions throughout the vaccine development. Activated DCs induce, activate and polarise T-cell responses by expression of distinct maturation markers and cytokines regulating the adaptive immune responses. In addition, they are uniquely adept at decoding the fungus-associated information and translate it in qualitatively different T helper responses. We find out, that C. glabrata mannan is able to induce proliferation of splenocytes and to increase the production of TNF-α and IL-4. Next, increased the expression of co-stimulatory molecules CD80 and CD86 and the proportion of CD4+CD25+ and CD4+CD28+ T cells during in vitro stimulation of splenocytes. Reported results provide C. glabrata mannan capability to modulate cytokine production, DCs activation and antigen presentation activity, influencing T-cell phenotype in response to stimulation.

Brazilian strains of Toxoplasma gondii are controlled by azithromycin and modulate cytokine production in human placental explants

BackgroundToxoplasma gondii is a protozoan parasite that causes congenital toxoplasmosis by transplacental transmission. Parasite strains are genetically diverse and disease severity is related to the genotype. In Uberlândia city, Brazil, two virulent strains were isolated: TgChBrUD1 and TgChBrUD2. Congenital toxoplasmosis is more prevalent in South America compared to Europe, and more often associated with severe symptoms, usually as a result of infection with atypical strains.MethodsConsidering that T. gondii has shown high genetic diversity in Brazil, the effectiveness of traditional treatment may not be the same, as more virulent strains of atypical genotypes may predominate. Thus, the aim of this study were to evaluate the Brazilian strain infection rate in human villous explants and the azithromycin efficacy with regard to the control of these strains compared to traditional therapy. Villi were infected with RH, ME49, TgChBrUD1 or TgChBrUD2 strains and treated with azithromycin, spiramycin or a combination of pyrimethamine plus sulfadiazine. The villous viability was analyzed by LDH assay and morphological analysis. Parasite proliferation, as well as production of cytokines was analyzed by qPCR and ELISA, respectively. Statistical analysis was performed using the GraphPad Prism 5.0.ResultsThe treatments were not toxic and TgChBrUD1 infected villi showed a higher parasite burden compared with others strains. Treatments significantly reduced the intracellular proliferation of T. gondii, regardless of the strain. TgChBrUD1-infected villi produced a larger amount of MIF, IL-6 and TGF-β1 compared with other infected villi. Azithromycin treatment increased MIF production by RH- or TgChBrUD2-infected villi, but in ME49- or TgChBrUD1-infected villi, the MIF production was not altered by treatment. On the other hand, azithromycin treatment induced lower IL-6 production by ME49- or TgChBrUD1-infected villi.ConclusionsAzithromycin treatment was effective against T. gondii Brazilian strains compared with conventional treatment. Also, the TgChBrUD1 strain replicated more in villi and modulated important cytokines involved in parasite control, showing that different strains use different strategies to evade the host immune response and ensure their survival.

Novel strains of Bacteroides fragilis and Bacteroides ovatus alleviate the LPS-induced inflammation in mice.

Lipopolysaccharide (LPS) can promote the expression of pro-inflammatory cytokines, damage the tight junction of epithelial walls, and thereby lead to chronic low-grade intestinal inflammatory disorders. Evidences of many beneficial functions from Bacteroides strains suggest their intervention capabilities in LPS-induced inflammation. In the present study, both healthy and LPS-treated mice were consistently treated with Bacteroides strains for 5days. The intestinal microbiota alteration, epithelial permeability, cytokine expression, and autoimmune and innate immune responses were analyzed. B. fragilis HCK-B3 and B. ovatus ELH-B2 from our laboratory collection were demonstrated to assist intestinal equilibrium by maintaining the diversity of gut microbiota and relieve LPS-induced inflammation by either modulating cytokine production or restoring the Treg/Th-17 balance. Our research indicated that the Bacteroides strains with capabilities of alleviating inflammation have the potential as therapeutics to prevent intestinal inflammatory disorders and provided scientific supports for discovering next-generation probiotics.

Cytokine and Adhesion Molecule Expression Induced by Different Strains of Staphylococcus aureus in Type 1 Diabetic Rats: Role of Insulin.

Introduction: Staphylococcus aureus may provoke peritonitis and death, especially in immunocompromized individuals such as diabetic patients. We evaluated the role of insulin in S. aureus-induced peritoneal infection in diabetic and non-diabetic rats.Materials/Methods: Alloxan-diabetic male Wistar rats and their respective controls received intraperitoneal injections of different strains of S. aureus or sterile phosphate-buffered saline. After 3 days of infection, the first set of diabetic and non-diabetic rats received 4 and 1 IU, respectively, of neutral protamine Hagedorn insulin and were analyzed 8 h later. The second set of diabetic and non-diabetic rats received 4 and 1 IU, respectively, of insulin 2 h before intraperitoneal infection and a half dose of insulin at 5 p.m. for the next 2 days and were analyzed 16 h later. The following measurements were performed: (a) number of cells in the peritoneal lavage fluid (PeLF), white blood cell count, and blood glucose; (b) serum insulin and corticosterone; (c) cytokine levels in the PeLF; (d) expression of adhesion molecules in the vascular endothelium; and (e) microbicidal activity.Results: Diabetic rats showed an increased number of polymorphonuclear leukocytes (PMNs) and increased concentrations of CINC-1, IL-4, and IFN-γ in the PeLF after infection with the ATCC 25923 or N315 αHL+ strain. The mesenteric expression of PECAM-1 was increased after infection with the N315 HLA+ strain. ICAM-1 expression was increased with ATCC infection. Treatment of diabetic rats with a single dose of insulin restored CINC-1 levels in the PeLF for both strains; however, PMN migration, IL-4, and IFN-γ were restored in rats infected with the ATCC strain, whereas the PeLF concentrations of CINC-2, IL-1β, and IL-4 were increased in N315-infected animals. Insulin restored PMN migration and CINC-2 levels in the PeLF in ATCC-infected rats. After multiple treatments with insulin, the levels of IL-1β, IL-6, and IFN-γ were increased in the PeLF of diabetic rats after infection with either strain, and CINC-2 levels were restored in N315-infected animals.Conclusion: These results suggest that insulin distinctively modulates cytokine production or release, PMN leukocyte migration, and adhesion molecule expression during the course of peritonitis induced by different strains of S. aureus.

Dental implant surfaces treated with phosphoric acid can modulate cytokine production by blood MN cells.

The study characterizes dental implant surfaces treated with phosphoric acid to assess the effects of acid treatment on blood cells and correlate them with cytokine levels. The implant surfaces examined were divided into untreated metal surface (US; n = 50), metal surface treated with phosphoric acid (ATS; n = 50) and cement surface (CS; n = 50) groups. The samples were characterized by scanning electron microscopy (SEM) and rheometry. The implants were incubated with human blood mononuclear cells for 24 h, with surface rinsing in the ATS treatment. Cell viability was determined by colorimetric methods and cytokines in the culture supernatant were quantified using flow cytometry. In the ATS group, the surface porosity and contact surface were increased and plaques were observed on the surface. The blood flow and viscosity curves were similar among the treatments, and the high cell viability rates indicate the biocompatibility of the materials used. An increase in the levels of IL-2, IL-4, IL-6, IL-10 and TNF-α was observed in the ATS and CS groups. There were positive correlations between IL-10 and IL-2 levels and between IL-10 and IL-4 levels in the culture supernatant of the ATS group. The results suggest that implant surface treatment with phosphoric acid activates the production of inflammatory cytokines. The increased cytokine levels can modulate the immune response, thereby improving biofunctional processes and promoting the success of dental implants.

Antidepressant therapy in patients with cancer: A clinical review

Background: The prevalence of major depressive disorder (MDD) by DSM criteria among cancer patients is about 14%–15% in oncological, hematological, and palliative services and the number is risen up to 20%–25% when other depressive disorders are also included. Like MDD patients in general, patients with cancer are thought to be underdiagnosed and undertreated. Untreated depression in cancer patients may lead to having distressed symptoms and signs, decreased quality of life, higher suicide risk, greater psychological burden on the family, longer hospital stays, poorer anticancer treatment compliance, as well as even increased risk for mortality. Methods: In this review, the authors reviewed published articles on the use of antidepressant use for patients with cancer, to familiarize the readers with the use of antidepressants. Results: Antidepressants have been found to be more effective than placebo in relieving depressive symptoms in patients with cancer, and the efficacy is positively associated with length of treatment. Although the rate of antidepressant prescription is increasing, still about 75% of cancer patients with depression have not yet received antidepressant treatment. Besides the use in treating mood and anxiety symptoms, antidepressants have also been found to have versatile roles as palliative treatment for cancer-related symptoms – pain, hot flushes, nausea, anorexia/cachexia, and fatigue. Furthermore, antidepressants have been studied for their anticancer potentials. They can inhibit tumor growth through either indirectly regulating immunity by enhancing cytotoxic activity and modulating cytokine production, or directly initiating cancer cell death and arresting cancer cell proliferation. We also found important drug-drug interaction between antidepressants and tamoxifen. Conclusion: Besides treating depressive and anxiety disorders, antidepressants are effective in treating cancer-related symptoms (pain, hot flushes, nausea, anorexia/cachexia, and fatigue). Cancer patients are eager to receive more effective treatment against their cancer as well as comorbid depression, and physicians should be more aggressive in providing every beneficial regimen – including an antidepressant.

6,7-Dehydroroyleanone diterpene derived from Tetradenia riparia essential oil modulates IL-4/IL-12 release by macrophages that are infected with Leishmania amazonensis.

The treatment of cutaneous leishmaniasis in associated with several adverse effects and therapeutic failure, resulting in patients' abandonment of treatment. Research on new drugs with leishmanicidal potential from medicinal plants is essential. The anti-Leishmania activity of Tetradenia riparia essential oil (TrEO) and its derivatives, such as the diterpene 6,7-dehydroroyleanone (TrROY), and the immunomodulatory effects of TrEO have been reported. However, few studies have investigated the effects of TrROY. The present study evaluated the modulation of cytokine production by murine macrophages that were infected with Leishmania amazonensis (6 parasites/macrophage) and treated with TrROY (0.1, 1, and 100μg/ml). Cytokine levels were measured by flow cytometry. The results were analyzed using Student's t test at a 95% confidence interval. Microscopic counting was performed to evaluate the inhibitory effects of TrROY on intracellular infection. TrROY modulated the production of cytokines that are essential for the immune defense response to Leishmania, with a decrease in interleukin-4 (IL-4) levels and an increase in IL-12 levels. A TrROY concentration of 0.1μg/ml was chosen for the subsequent experiments. This dose was chosen because it modulated IL-4/IL-12 release by murine macrophages that were infected with Leishmania and because it presented no cytotoxic effects. TrROY (0.1μg/ml) induced a 31% reduction of the rate of infection in murine macrophages compared with untreated cells. TrROY may be a promising leishmanicidal agent. Further in vitro and in vivo studies should be conducted to evaluate the anti-Leishmania and immunomodulatory activity of TrROY.

In vitro and in vivo Effects of Lactate on Metabolism and Cytokine Production of Human Primary PBMCs and Monocytes.

Lactate, the end product of anaerobic glycolysis, is produced in high amounts by innate immune cells during inflammatory activation. Although immunomodulating effects of lactate have been reported, evidence from human studies is scarce. Here we show that expression of genes involved in lactate metabolism and transport is modulated in human immune cells during infection and upon inflammatory activation with TLR ligands in vitro, indicating an important role for lactate metabolism in inflammation. Extracellular lactate induces metabolic reprogramming in innate immune cells, as evidenced by reduced glycolytic and increased oxidative rates of monocytes immediately after exposure to lactate. A short-term infusion of lactate in humans in vivo increased ex vivo glucose consumption of PBMCs, but effects on metabolic rates and cytokine production were limited. Interestingly, long-term treatment with lactate ex vivo, reflecting pathophysiological conditions in local microenvironments such as tumor or adipose tissue, significantly modulated cytokine production with predominantly anti-inflammatory effects. We found time- and stimuli-dependent effects of extracellular lactate on cytokine production, further emphasizing the complex interplay between metabolism and immune cell function. Together, our findings reveal lactate as a modulator of immune cell metabolism which translates to reduced inflammation and may ultimately function as a negative feedback signal to prevent excessive inflammatory responses.

HDAC inhibitors modulate innate immune responses to micro-organisms relevant to chronic mucocutaneous candidiasis

Signal transducer and activator of transcription 1 (STAT-1) gain-of-function (GOF) mutations cause chronic mucocutaneous candidiasis (CMC), a disease associated with Candida albicans and Staphylococcus aureus infection. Patients suffer from dysegulated immune responses due to aberrant cell programming and function. We investigated the effect of inhibitory molecules targeting histone deacetylases (HDACi) on the immune responses of peripheral blood mononuclear cells (PBMCs) of healthy controls and patients with CMC towards microbes relevant for CMC. PBMCs cells were pretreated with HDACi and challenged with C. albicans or S. aureus. Innate and adaptive cytokines were measured in cell culture supernatants by enzyme-linked immunosorbent assay (ELISA). We assessed the effect of HDAC inhibitors on T helper type 1 (Th1) and Th17 cells and measured STAT-1 and STAT-3 phosphorylation using flow cytometry. Panobinostat, a pan-HDAC inhibitor, strongly inhibits innate and adaptive cytokines upon challenge with C. albicans or S. aureus. Specific inhibitors (entinostat or RGFP966) also had a tendency to lower production of most innate cytokines in CMC patient cells. Entinostat and RGFP966 increased the production of interleukin (IL)-22 specifically after S. aureus challenge in patient cells. In healthy and control cells, entinostat and RGFP966 treatment down-regulated STAT-1 phosphorylation while pSTAT-3 levels remained stable. HDACi modulate cytokine production in response to C. albicans and S. aureus. Pan-inhibitors lower overall cytokine production, whereas specific inhibitors confer a selective effect. Entinostat and RGFP966 are promising therapeutic candidates to treat STAT-1 GOF due to their capacity to restore IL-22 production and decrease STAT-1 phosphorylation; however, their inhibition of innate cytokines poses a possible risk to secondary infections.

Application of Deacetylated Poly-N-Acetyl Glucosamine Nanoparticles for the Delivery of miR-126 for the Treatment of Cecal Ligation and Puncture-Induced Sepsis.

Sepsis is an acute inflammatory syndrome in response to infection. In some cases, excessive inflammation from sepsis results in endothelial dysfunction and subsequent increased vascular permeability leading to organ failure. We previously showed that treatment with endothelial progenitor cells, which highly express microRNA-126 (miR-126), improved survival in mice subjected to cecal ligation and puncture (CLP) sepsis. miRNAs are important regulators of gene expression and cell function, play a major role in endothelial homeostasis, and may represent an emerging therapeutic modality. However, delivery of miRNAs to cells in vitro and in vivo is challenging due to rapid degradation by ubiquitous RNases. Herein, we developed a nanoparticle delivery system separately combining deacetylated poly-N-acetyl glucosamine (DEAC-pGlcNAc) polymers with miRNA-126-3p and miRNA-126-5p and testing these combinations in vitro and in vivo. Our results demonstrate that DEAC-pGlcNAc polymers have an appropriate size and zeta potential for cellular uptake and when complexed, DEAC-pGlcNAc protects miRNA from RNase A degradation. Further, DEAC-pGlcNAc efficiently encapsulates miRNAs as evidenced by preventing their migration in an agarose gel. The DEAC-pGlcNAc-miRNA complexes were taken up by multiple cell types and the delivered miRNAs had biological effects on their targets in vitro including pERK and DLK-1. In addition, we found that delivery of DEAC-pGlcNAc alone or DEAC-pGlcNAc:miRNA-126-5p nanoparticles to septic animals significantly improved survival, preserved vascular integrity, and modulated cytokine production. These composite studies support the concept that DEAC-pGlcNAc nanoparticles are an effective platform for delivering miRNAs and that they may provide therapeutic benefit in sepsis.

Leukocyte Immunoglobulin-Like Receptors A2 and A6 are Expressed in Avian Macrophages and Modulate Cytokine Production by Activating Multiple Signaling Pathways.

The activating leukocyte immunoglobulin-like receptors (LILRAs) play an important role in innate immunity. However, most of the LILRA members have not been characterized in avian species including chickens. The present study is the first attempt at cloning, structural analysis and functional characterization of two LILRAs (LILRA2 and LILRA6) in chickens. Multiple sequence alignments and construction of a phylogenetic tree of chicken LILRA2 and LILRA6 with mammalian proteins revealed high conservation between chicken LILRA2 and LILRA6 and a close relationship between the chicken and mammalian proteins. The mRNA expression of LILRA2 and LILRA6 was high in chicken HD11 macrophages and the small intestine compared to that in several other tissues and cells tested. To examine the function of LILRA2 and LILRA6 in chicken immunity, LILRA2 and LILRA6 were transfected into HD11 cells. Our findings indicated that LILRA2 and LILRA6 are associated with the phosphorylation of Src kinases and SHP2, which play a regulatory role in immune functions. Moreover, LILRA6 associated with and activated MHC class I, β2-microglobulin and induced the expression of transporters associated with antigen processing but LILRA2 did not. Furthermore, both LILRA2 and LILRA6 activated JAK-STAT, NF-κB, PI3K/AKT and ERK1/2 MAPK signaling pathways and induced Th1-, Th2- and Th17-type cytokines and Toll-like receptors. Collectively, this study indicates that LILRA2 and LILRA6 are essential for macrophage-mediated immune responses and they have the potential to complement the innate and adaptive immune system against pathogens.

Virucidal, antiviral and immunomodulatory activities of β-escin and Aesculus hippocastanum extract.

β-Escin, one of the constituents of Aesculus hippocastanum L. (Hippocastanaceae) seed extract (AH), inhibits NF-κB activation, which plays an important role in HSV-1 replication. The aim was to examine the antiherpetic activity of β-escin and AH, as well as their effect on the activation of NF-κB and AP-1 and cytokine secretion in epithelial cells and macrophages. Cell viability was evaluated using MTT assay, and antiviral and virucidal activity was determined by plaque assay. The effect on NF-κB and AP-1 signalling pathways activation was determined by a luciferase reporter assay, and cytokine production was measured by ELISA. β-Escin and AH had virucidal and anti-HSV-1 activities, and the antiviral activity was discovered for other enveloped viruses (VSV and Dengue). Moreover, β-escin and AH significantly reduced NF-κB and AP-1 activation and cytokine production in macrophages stimulated with HSV-1 and TLRs ligands. However, an enhanced activation of these pathways and an increase in the levels of pro-inflammatory cytokines in β-escin and AH-treated HSV-1-infected epithelial cells were found. This study demonstrates virucidal and broad-spectrum antiviral activities for β escin and AH. Besides, β-escin and AH modulate cytokine production depending on the stimuli (viral or non-viral) and the cell type under study.

Cytokine Production Is Differentially Modulated in Malignant and Non-malignant Tissues in ST2-Receptor Deficient Mice.

IL-33/ST2 axis has been shown to exert both pro- and anti- effects in wound healing and tumor development. To further understand the role of this cytokine complex, we characterized comparatively the inflammatory component of a malignant tissue and non-malignant tissue in mice lacking ST2 receptor (ST2-KO). KO mice and their wild-type (WT) counterparts were either implanted subcutaneously with polyether-polyurethane sponge discs to induce non-malignant fibrovascular tissue growth or inoculated with 4T1 cells to induce mammary tumor. Loss of ST2 receptor in mice resulted in enhanced mammary tumor and fibrovascular tissue relative to the WT animals. The inflammatory parameters (MPO and NAG activities, levels of the cytokines CXCL1/KC, CCL2, TNF-α, TGF-β1, and mast cell number) were differentially modulated in both tissues. In tumors, these parameters were, overall, lower compared with those in tumors of WT mice. In KO implants, CXCL1/KC and TNF-α levels increased; MPO, NAG, and CCL2 levels decreased relative to the WT implants. In addition, deletion of ST2 receptor inhibited mast cell recruitment but had no effect on TGF-β1 levels in implants. Our study has shown antitumorigenic effect of ST2 in mammary tumor and this may be mediated by downregulation of pro-inflammatory cytokines (CXCL1/KC, CCL2, TNF-α, and TGF-β1). Conversely, in the fibrovascular tissue, lack of ST2 receptor resulted in differential modulation of cytokine production. Differential signaling mechanisms may be activated by IL-33/ST2 axis to modulate cytokine production in malignant and non-malignant proliferative processes.