Lower Levels Of Proinflammatory Cytokines Research Articles

Obesity as a contributor to immunopathology in pregnant and non-pregnant adults with COVID-19.

The ongoing coronavirus disease 2019 (COVID‐19) pandemic has led to a global public health emergency with the need to identify vulnerable populations who may benefit from increased screening and healthcare resources. Initial data suggest that overall, pregnancy is not a significant risk factor for severe coronavirus disease 2019 (COVID‐19). However, case series have suggested that maternal obesity is one of the most important comorbidities associated with more severe disease. In obese individuals, suppressors of cytokine signaling are upregulated and type I and III interferon responses are delayed and blunted leading to ineffective viral clearance. Obesity is also associated with changes in systemic immunity involving a wide range of immune cells and mechanisms that lead to low‐grade chronic inflammation, which can compromise antiviral immunity. Macrophage activation in adipose tissue can produce low levels of pro‐inflammatory cytokines (TNF‐α, IL‐1β, IL‐6). Further, adipocyte secretion of leptin is pro‐inflammatory and high circulating levels of leptin have been associated with mortality in patients with acute respiratory distress syndrome. The synergistic effects of obesity‐associated delays in immune control of COVID‐19 with mechanical stress of increased adipose tissue may contribute to a greater risk of pulmonary compromise in obese pregnant women. In this review, we bring together data regarding obesity as a key co‐morbidity for COVID‐19 in pregnancy with known changes in the antiviral immune response associated with obesity. We also describe how the global burden of obesity among reproductive age women has serious public health implications for COVID‐19.

Possible mechanisms involved in improved beta cell function in pregnant women with type 1 diabetes

Pregnancy is known to be associated with an increased demand for insulin that is normally compensated by an increased beta cell mass and insulin secretion. Recent studies have suggested enhanced beta cell function during pregnancy in women with type 1 diabetes (T1D). To explore the possible mechanisms behind enhanced beta cell function during pregnancy in women with T1D we investigated the impact of circulating factors in serum from nine women from each group of pregnant women with and without T1D, after pregnancy and non-diabetic non-pregnant women on rat islet cell proliferation and apoptosis, and on T-lymphocyte activation. In addition, circulating levels of pancreatic hormones and selected cytokines and adipokines were measured. Rat islet cell proliferation was higher in serum from pregnant women with T1D (p < 0.05) compared to T1D women after pregnancy. Apoptosis in INS-1E cell was lower (p < 0.05) in serum from pregnant women with T1D compared to T1D women after pregnancy. T-lymphocyte cell (Jurkat) proliferation was reduced by serum from pregnant women without T1D only (p < 0.05). Higher C-peptide levels and lower levels of ghrelin, IL-6, MCP-1, IL-8 and adipsin were observed in pregnant women with T1D compared to T1D women after pregnancy. In conclusion, the improved beta cell function in women with T1D during pregnancy may be due to lower levels of proinflammatory cytokines and/or higher levels of pregnancy-associated growth factors.

Anthocyanins isolated from Hibiscus syriacus L. attenuate lipopolysaccharide-induced inflammation and endotoxic shock by inhibiting the TLR4/MD2-mediated NF-κB signaling pathway

BackgroundHibiscus syriacus L. has been used as a medicinal plant in many Asian countries. However, anti-inflammatory activity of H. syriacus L. remains unknown. PurposeThis study was aimed to investigating the anti-inflammatory effect of anthocyanin fractions from the H. syriacus L. variety Pulsae (PS) on the lipopolysaccharide (LPS)-induced inflammation and endotoxic shock. Study design and methodsMTT assay and flow cytometry analysis were performed to determine cytotoxicity of PS. RT-PCR, western blotting, and ELISA were conducted to evaluate the expression of proinflammatory mediators and cytokines. Molecular docking study predicted the binding scores and sites of PS to TLR4/MD2 complex. Immunohistochemical assay was conducted to evaluate the binding capability of PS to TLR4/MD2 and nuclear translocation of NF-κB p65. A zebrafish endotoxic shock model was used to evaluate anti-inflammatory activity of PS in vivo. ResultsPS suppressed LPS-induced nitric oxide and prostaglandin E2 secretion concomitant with the downregulation of inducible nitric oxide synthase and cyclooxygenase-2 expression. Furthermore, PS inhibited the production of proinflammatory cytokines such as TNF-α, IL-6, and IL-12 in LPS-stimulated RAW 264.7 macrophages. Additionally, molecular docking data showed that PS mostly fit into the hydrophobic pocket of MD2 and bound to TLR4. In particular, apigenin-7-O-glucoside powerfully bound to MD2 and TLR4 via hydrogen bonding. Additionally, immunohistochemistry assay revealed that PS inhibited LPS-induced TLR4 dimerization or expression on the cell surface, which consequently decreased MyD88 recruitment and IRAK4 phosphorylation, resulting in the inhibition of NF-κB activity. PS also attenuated LPS-mediated mortality and abnormality in zebrafish larvae and diminished the recruitment of neutrophils and macrophages at the inflammatory site accompanied by the low levels of proinflammatory mediators and cytokines. ConclusionPS might be a novel immunomodulator for the effective treatment of LPS-mediated inflammatory diseases.

Psychological stress creates an immune-suppressive environment that increases the susceptibility of aged mice to Mycobacterium tuberculosis infection

Abstract Age is a risk factor for chronic infections, including tuberculosis (TB). A second compounding factor of TB susceptibility is psychological stress, which is particularly acute in older individuals. While the influence of psychological stress in TB is well documented, the mechanisms by which stress influences M.tb susceptibility in the elderly are almost completely unknown. To study the effects of chronic psychological stress on M.tb infection in old mice, we employed a mouse social stressor model (called social disruption stress or SDR) which involves repeated social defeat in subordinate mice. Young (3 month) and old (18 month) C57BL/6 mice were subjected to SDR and bronchial fluid (BF) and alveolar macrophages (AMs) were isolated by lung lavage. Our studies showed that SDR created an immune-suppressive lung environment in old mice, based on lower levels of pro-inflammatory cytokines and chemokines in bronchial fluid (BF) or their mRNA expression by AMs. AMs from old SDR mice compared to non-stressed mice were also deficient in their ability to mount an inflammatory cytokine response or induce MHC class II mRNA expression. To determine the effect of SDR on M.tb growth, young and old mice were subjected to SDR and infected with M.tb. At 30 days, SDR in both young and old mice reduced M.tb burden. However, this was transient as at 60 days M.tb burden was higher in old mice compared to young mice and SDR further significantly increased M.tb burden in old mice. Also we found that SDR at 60 days in old mice induced significantly higher levels of IL-10 and IL-17 mRNA in the lung, which favors growth of M.tb. In conclusion, our studies suggest that psychological stress during the initial stage of Mtb infection has long-term impact on the control of the infection.

Macrophage M2 polarization induced by exosomes from adipose-derived stem cells contributes to the exosomal proangiogenic effect on mouse ischemic hindlimb

BackgroundM2 macrophages and exosomes from adipose-derived stem cells (ASCs) are both reported to promote angiogenesis. However, the possible synergistic effects between exogenous exosomes and endogenous M2 macrophages are poorly understood.MethodsExosomes were isolated from conditioned medium of normoxic and hypoxic ASCs using the combined techniques of ultrafiltration and size-exclusion chromatography and were identified with nanoparticle tracking analysis and immunoblotting for exosomal markers. Macrophages were collected from the mouse peritoneal cavity. M1 and M2 macrophages were detected by immunoblotting for the intracellular markers inducible nitric oxide synthase (iNOS) and arginase-1 (Arg-1) and by flow cytometry for the surface markers F4/80, CD86, and CD206. Murine models of Matrigel plug and hindlimb ischemia were employed as in vivo angiogenic assays.ResultsWhen M1 macrophages were treated with exosomes from normoxic ASCs (Nor/Exo), and particularly from hypoxic ASCs (Hyp/Exo), the expression of the M1 marker iNOS decreased, and the M2 marker Arg-1 increased in a time- and dose-dependent manner. Additionally, a decrease in the M1 surface marker CD86 and an increase in the M2 surface marker CD206 were observed, which suggested that M1 macrophages were polarized to an M2-like phenotype. Conditioned medium from these M2-like macrophages presented lower levels of proinflammatory cytokines and higher levels of proangiogenic factors and promoted endothelial cell proliferation, migration, and tube formation. Furthermore, M2 polarization and angiogenesis were induced upon the administration of exosomes in mouse Matrigel plug and hindlimb ischemia (HLI) models. Interestingly, these exosomal effects were attenuated by using a colony stimulating factor 1 receptor (CSF-1R) inhibitor, BLZ945, in vitro and in vivo. Downregulation of microRNA-21 (miR-21) in hypoxic ASCs reduced the exosomal effects on M2 polarization, Akt phosphorylation, and CSF-1 secretion. A similar reduction in exosomal activity was also observed when exosomes were administered along with BLZ945.ConclusionOur findings provide evidence that exosomes from ASCs polarize macrophages toward an M2-like phenotype, which further enhances the exosomal proangiogenic effects. Exosomal delivery of miR-21 and positive feedback of secreted CSF-1 may be involved in macrophage polarization.

ALKS 4230: a novel engineered IL-2 fusion protein with an improved cellular selectivity profile for cancer immunotherapy

BackgroundInterleukin-2 (IL-2) plays a pivotal role in immune homeostasis due to its ability to stimulate numerous lymphocyte subsets including natural killer (NK) cells, effector CD4+ and CD8+ T cells, and...

M-CSF- and L929-derived macrophages present distinct metabolic profiles with similar inflammatory outcomes.

Macrophages are essential components of the immune system. Macrophages can be derived from the bone marrow of mice with either recombinant M-CSF or L929 supernatant. Recent literature considers recombinant M-CSF- and L929-derived macrophages as equals, even though L929-derived macrophages are exposed to other substances secreted in the L929 supernatant, and not only M-CSF. Thus, we decided to perform a comparative analysis of both inflammatory and metabolic profiles of macrophages differentiated under the aforementioned conditions, which is relevant for standardization and interpretation of in vitro studies. We observed that, when treated with LPS, L929macs secrete lower levels of proinflammatory cytokines (TNF-α, IL-6, IL12) and present higher glycolysis and oxygen consumption when compared with M-CSFmacs. L929macs also have increased mitochondrial mass, with higher percentage of dysfunctional mitochondria. This sort of information can help direct further studies towards a more specific approach for macrophage generation.

Riluzole improves functional recovery after acute spinal cord injury in rats and may be associated with changes in spinal microglia/macrophages polarization

Spinal cord injury (SCI) triggers pronounced inflammatory responses that are accompanied by neuronal disruption and functional deficits. SCI treatment remains an unmet clinical need. Emerging evidence suggests that riluzole may exert a neuroprotective effect due to its anti-inflammatory properties. However, details of the underlying mechanisms remain poorly defined. The polarization of microglial/macrophages has an important role in neuroinflammation. Here, we examined whether riluzole can exert a neuroprotective effect after acute SCI, and whether this effect is associated with changes in microglia/macrophages polarization. Riluzole (4 mg/kg) or vehicle were injected intraperitoneally (i.p.) in female rats immediately following SCI and repeated for 7 consecutive days (b.i.d.). Compared with vehicle treatment, riluzole-treated SCI rats showed significant higher locomotor scores (Basso, Beattie, and Bresnahan score, Inclined Plane test score, n = 18/group). Riluzole-treated rats also developed smaller spinal cavities, showed higher levels of myelin basic protein (MBP) and neurofilament (NF)200 immunoreactivities, and lower levels of proinflammatory cytokines in the spinal cord at 7 days post-SCI. Immunofluorescence study revealed more CD206+ cells and less iNOS+ cells in the injured spinal cord of riluzole-treated SCI rats, as compared to vehicle control. Using real-time PCR, we found that riluzole upregulated the mRNA levels of M2 markers, but downregulated that of M1 markers, as compared to the vehicle treatment. Current findings suggest that systemic administration of riluzole after acute SCI facilitated motor function recovery and inhibited inflammatory responses, which may be associated with polarization of M2 microglia/macrophages.

Methylomic Changes of Autophagy-Related Genes by Legionella Effector Lpg2936 in Infected Macrophages.

Legionella pneumophila (L. pneumophila) is a Gram-negative bacterium that infects the human respiratory tract causing Legionnaires’ disease, a severe form of pneumonia. Recently, rising evidence indicated the ability of Legionella to regulate host defense via its type 4 secretion system including hundreds of effectors that promote intracellular bacterial replication. The host defense against such invaders includes autophagic machinery that is responsible for degradation events of invading pathogens and recycling of cell components. The interplay between host autophagy and Legionella infection has been reported, indicating the role of bacterial effectors in the regulation of autophagy during intracellular replication. Here, we investigated the potential impact of Legionella effector Lpg2936 in the regulation of host autophagy and its role in bacterial replication using mice-derived macrophages and human lung epithelial cells (A549 cells). First, monitoring of autophagic flux following infection revealed a marked reduction of Atg7 and LC3B expression profile and low accumulation levels of autophagy-related LC3-I, LC3-II, and the Atg12–Atg5 protein complex. A novel methyladenine alteration was observed due to irreversible changes of GATC motif to G(6 mA) TC in the promoter region of Atg7 and LC3B indicated by cleaved genomic-DNA using the N6 methyladenine-sensitive restriction enzyme DpnI. Interestingly, RNA interference (RNAi) of Lpg2936 in infected macrophages showed dramatic inhibition of bacterial replication by restoring the expression of autophagy-related proteins. This is accompanied by low production levels of bacterial-associated pro-inflammatory cytokines. Furthermore, a constructed Lpg2936 segment in the GFP expression vector was translocated in the host nucleus and successfully induced methyladenine changes in Atg7 and LC3B promoter region and subsequently regulated autophagy in A549 cells independent of infection. Finally, treatment with methylation inhibitors 5-AZA and (2)-Epigallocatechin-3-gallate (EGCG) was able to restore autophagy-related gene expression and to disrupt bacterial replication in infected macrophages. This cumulative evidence indicates the methylation effect of Legionella effector Lpg2936 on the host autophagy-related molecules Atg7 and LC3B and subsequent reduction in the expression levels of autophagy effectors during intracellular replication of L. pneumophila.

Daphnetin Ameliorates Experimental Autoimmune Encephalomyelitis Through Regulating Heme Oxygenase-1.

To assess the potential role of daphnetin, a clinically used anti-inflammatory agent, on the development of the inflammatory and neurodegenerative disease, we investigated its immune regulatory function in a murine model of experimental autoimmune encephalomyelitis (EAE). Significantly, lower levels of pro-inflammatory cytokines including interleukin (IL)-17, interferon-γ, Il6, Il12a, and Il23a were observed in brains of daphnetin-treated EAE mice, compared with those in control littermates. We also confirmed that daphnetin suppressed the production of IL-1β, IL-6, and tumor necrosis factor-α in lipopolysaccharide-stimulated mouse BV2 microglial cells. Mechanistically, heme oxygenase-1 (HO-1), a canonical anti-oxidant and anti-inflammatory factor, was found to be substantially induced by daphnetin treatment in BV2 cells. Also, a significantly higher level of HO-1, accompanied by a decreased level of malondialdehyde, was observed in daphnetin-treated EAE mice. More importantly, the deletion of HO-1 in BV2 microglia largely abrogated daphnetin-mediated inhibition of the inflammatory response. Together, our data demonstrate that daphnetin has an anti-inflammatory and neuroprotective role during the pathogenesis of EAE, which is partially at least, dependent on its regulation of HO-1.

Immobilized Macrophage Colony-Stimulating Factor (M-CSF) Regulates the Foreign Body Response to Implanted Materials.

The functionality and durability of implanted biomaterials are often compromised by an exaggerated foreign body reaction (FBR). M1/M2 polarization of macrophages is a critical regulator of scaffold-induced FBR. Macrophage colony-stimulating factor (M-CSF), a hematopoietic growth factor, induces macrophages into an M2-like polarized state, leading to immunoregulation and promoting tissue repair. In the present study, we explored the immunomodulatory effects of surface bound M-CSF on poly-l-lactic acid (PLLA)-induced FBR. M-CSF was immobilized on the surface of PLLA via plasma immersion ion implantation (PIII). M-CSF functionalized PLLA, PLLA-only, and PLLA+PIII were assessed in an IL-1β luciferase reporter mouse to detect real-time levels of IL-1β expression, reflecting acute inflammation in vivo. Additionally, these different treated scaffolds were implanted subcutaneously into wild-type mice to explore the effect of M-CSF in polarization of M2-like macrophages (CD68+/CD206+), related cytokines (pro-inflammatory: IL-1β, TNF and MCP-1; anti-inflammatory: IL-10 and TGF-β), and angiogenesis (CD31) by immunofluorescent staining. Our data demonstrated that IL-1β activity in M-CSF functionalized scaffolds was ∼50% reduced compared to PLLA-only at day 1 (p < 0.01) and day 2 (p < 0.05) post-implantation. There were >2.6-fold more CD206+ macrophages in M-CSF functionalized PLLA compared to PLLA-only at day 7 (p < 0.001), along with higher levels of IL-10 at both day 7 (p < 0.05) and day 14 (p < 0.01), and TGF-β at day 3 (p < 0.05), day 7 (p < 0.05), and day 14 (p < 0.001). Lower levels of pro-inflammatory cytokines were also detected in M-CSF functionalized PLLA in the early phase of the immune response compared to PLLA-only: a ∼58% decrease at day 3 in IL-1β; a ∼91% decrease at day 3 and a ∼66% decrease at day 7 in TNF; and a ∼60% decrease at day 7 in MCP-1. Moreover, enhanced angiogenesis inside and on/near the scaffold was observed in M-CSF functionalized PLLA compared to PLLA-only at day 3 (p < 0.05) and day 7 (p < 0.05), respectively. Overall, M-CSF functionalized PLLA enhanced CD206+ macrophage polarization and angiogenesis, consistent with lower levels of pro-inflammatory cytokines and higher levels of anti-inflammatory cytokines in early stages of the host response, indicating potential immunoregulatory functions on the local environment.

Associations of viral ribonucleic acid (RNA) shedding patterns with clinical illness and immune responses in Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection.

ObjectivesA wide range of duration of viral RNA shedding in patients infected with Severe Acute Respiratory Syndrome Coronavirus 2 (SARS‐CoV‐2) has been observed. We aimed to investigate factors associated with prolonged and intermittent viral RNA shedding in a retrospective cohort of symptomatic COVID‐19 patients.MethodsDemographic, clinical and laboratory data from hospitalised COVID‐19 patients from a single centre with two consecutive negative respiratory reverse transcription‐polymerase chain reaction (RT‐PCR) results were extracted from electronic medical records. Kaplan–Meier survival curve analysis was used to assess the effect of clinical characteristics on the duration and pattern of shedding. Plasma levels of immune mediators were measured using Luminex multiplex microbead‐based immunoassay.ResultsThere were 201 symptomatic patients included. Median age was 49 years (interquartile range 16–61), and 52.2% were male. Median RNA shedding was 14 days (IQR 9–18). Intermittent shedding was observed in 77 (38.3%). We did not identify any factor associated with prolonged or intermittent viral RNA shedding. Duration of shedding was inversely correlated with plasma levels of T‐cell cytokines IL‐1β and IL‐17A at the initial phase of infection, and patients had lower levels of pro‐inflammatory cytokines during intermittent shedding.ConclusionsLess active T‐cell responses at the initial phase of infection were associated with prolonged viral RNA shedding, suggesting that early immune responses are beneficial to control viral load and prevent viral RNA shedding. Intermittent shedding is common and may explain re‐detection of viral RNA in recovered patients.

TRIM21 controls Toll-like receptor 2 responses in bone-marrow-derived macrophages.

SummaryTRIM21 is an interferon‐stimulated E3 ligase that controls the activity of pattern‐recognition signaling via ubiquitination of interferon regulatory factors and DDX41. Previous studies on the role of TRIM21 in innate immune responses have yielded contradictory results, suggesting that the role of TRIM21 is cell specific. Here, we report that bone‐marrow‐derived macrophages (BMDMs) generated from Trim21 −/− mice have reduced expression of mature macrophage markers. Reflecting their reduced differentiation in response to macrophage colony‐stimulating factor (M‐CSF), Trim21 −/− BMDMs had decreased expression of M‐CSF signature genes. Although Trim21 −/− BMDMs responded normally to Toll‐like receptor 9 (TLR9) activation, they produced lower levels of pro‐inflammatory cytokines in response to the TLR2 agonist PAM3CSK4. In line with this, the response to infection with the Bacillus Calmette–Guérin strain of Mycobacterium bovis was also diminished in Trim21 −/− BMDMs. Our results indicate that TRIM21 controls responses to TLR2 agonists.

The effect of zinc supplementation on pro-inflammatory cytokines (TNF-α, IL-1 AND IL-6) in mice with Escherichia coli LPS-induced diarrhea

Inflammation in the intestine causes diarrhea due to an increased release of pro-inflammatory cytokines such as TNF-α, IL-1, and IL-6. These are triggered by the exposure of E. coli-LPS to epithelial cells of the intestinal mucosa as well as low concentration of zinc in plasma such as in infants or children who are experiencing diarrhea. This paper aims to determine the effects of zinc supplementation on pro-inflammatory cytokines (TNF-α, IL-1 and IL-6) in mice with E. coli-LPS-induced diarrhea. This study used a controlled trial experimental design in the laboratory. A sample size of 20 mice were randomly divided into 4 groups: 1) Control group was given standard foods, 2) Trial group was given E. coli-LPS 2.5 mg/kg/oral once on day1, 3) Prevention group was given E. coli-LPS + 30 mg/kg/oral of zinc once daily for 12 days, 4) Therapeutic group was given E. coli-LPS, and were then given 30 mg/kg/oral of zinc once daily for 12 days if diarrhea occurred. Blood samples of mice were taken through the orbital sinus on the 0, 5th, 10th hour, and on the 4th, 8th and 12th days. Positive effects of zinc supplementation on levels of pro-inflammatory cytokines were observed, in which the higher levels of zinc were present, the lower levels of pro-inflammatory cytokines, especially TNF-α were observed. However, there was an increase of IL-1 and IL-6 levels on the 8th day in the prevention and therapeutic groups. Oral zinc supplementation had a significant positive effect on the levels of pro-inflammatory cytokines. Where there were higher levels of zinc, lower levels of pro-inflammatory cytokines TNF-α were present.

A TLR7 agonist strengthens T and NK cell function during BRAF-targeted therapy in a preclinical melanoma model.

Therapeutic success of targeted therapy with BRAF inhibitors (BRAFi) for melanoma is limited by resistance development. Observations from preclinical mouse models and recent insights into the immunological effects caused by BRAFi give promise for future development of combination therapy for human melanoma. In our study, we used the transplantable D4M melanoma mouse model with the BRAFV600E mutation and concomitant PTEN loss in order to characterize alterations in tumor‐infiltrating effector immune cells when tumors become resistant to BRAFi. We found that BRAFi‐sensitive tumors displayed a pronounced inflammatory milieu characterized by high levels of cytokines and chemokines accompanied by an infiltration of T and NK cells. The tumor‐infiltrating effector cells were activated and produced high levels of IFN‐γ, TNF‐α and granzyme B. When tumors became resistant and progressively grew, they reverted to a low immunogenic state similar to untreated tumors as reflected by low mRNA levels of proinflammatory cytokines and chemokines and fewer tumor‐infiltrating T and NK cells. Moreover, these T and NK cells were functionally impaired in comparison to their counterparts in BRAFi‐sensitive tumors. Their effector cell function could be restored by additional peritumoral treatment with the TLR7 agonist imiquimod, a clinically approved agent for nonmelanoma skin cancer. Indeed, resistance to BRAFi therapy was delayed and accompanied by high numbers of activated T and NK cells in tumors. Thus, combining BRAFi with an immune stimulating agent such as a TLR ligand could be a promising alternative approach for the treatment of melanoma.

Unmethylated CpG motif-containing genomic DNA fragment of Bacillus calmette-guerin promotes macrophage functions through TLR9-mediated activation of NF-κB and MAPKs signaling pathways.

The potency of synthetic CpG-oligo-deoxynucleotides (CpG-ODNs) adjuvants in modulating the immune cell functions through the TLR pathway has been tested and reported previously. However, the cellular signaling involved in the stimulation of macrophages by natural, CpG motif-containing adjuvant and the effector functions modulated by such stimulation has not been well studied. Here, we used in vitro and ex vivo murine macrophage assay systems, and mouse model of in vivo stimulation to explore the signaling pathway and the effector functions mediated by BC01. Results show that BC01 can induce the production of TNF-α and MCP-1 in macrophages by up-regulating the activation of NF-κB and MAPKs signaling pathway, and elevated the expression of MHC-II, CD40, CD80, and CD86. Upon stimulation with BC01, the peritoneal macrophages isolated from TLR9−/− mice produced significantly low levels of pro-inflammatory cytokines, attenuated the activation of NF-κB and MAPKs signaling pathways, and showed reduced phagocytosis. Following in vivo stimulation with BC01, the TLR9−/− mice produced significantly lower levels of pro-inflammatory cytokines in the serum and lymph nodes showed reduced cell proliferation. These results indicate that BC01 is an efficient agonist of TLR9 that can significantly enhance the host-protective immune functions of macrophages.

Fiber and phenolic compounds contribution to the hepatoprotective effects of mango diets in rats fed high cholesterol/sodium cholate.

The present study evaluated the contribution of mango fiber (MF) and mango phenolic compounds (MP) to the hepatoprotective effect of freeze-dried mango pulp (FDM) cultivar (cv.) "Ataulfo" diets in high cholesterol/sodium cholate (HCC)-fed rats. Male Wistar rats were fed with a HCC diet for 12 weeks, either untreated, or supplemented with MF, MP, FDM, or a control diet (no HCC; n = 6/group). All mango treatments significantly decreased hepatic cholesterol deposition and altered its fatty acid profile, whereas MF and MP mitigated adipose tissue hypertrophy. MF caused a lower level of proinflammatory cytokines (IL-1α/β, IFN-γ, TNF-α) whereas FDM increased the anti-inflammatory ones (IL-4, 6, 10). Mango treatments increased catalase (CAT) activity and its mRNA expression; superoxide dismutase (SOD) activity was normalized by MF and FDM, but its activity was unrelated to its hepatic mRNA expression. Changes in CAT and SOD mRNA expression were unrelated to altered Nrf2 mRNA expression. Higher hepatic PPARα and LXRα mRNA levels were found in MP and MF. We concluded that MF and MP are highly bioactive, according to the documented hepatoprotection in HCC-fed rats; their mechanism of action appears to be related to modulating cholesterol and fatty acid metabolism as well as to stimulating the endogenous antioxidant system.

Pemphigus foliaceus patients (Fogo Selvagem) treated with kinesiotherapy presented lower levels of proinflammatory cytokines.

Fogo Selvagem (FS) is a rare autoimmune disease characterized by acantholysis and inflammation of the epidermis. It was evidenced in this disease the increase of proinflammatory cytokines levels which can be influenced by physical activities. Kinesiotherapy, as physiotherapeutic interventions, was associated improvement levels of the quality of live, mainly the pain. Understanding the impact of such methodology in immunology of the FS, may constitute an alternative and effective approach. We compare the levels of serum cytokines and chemokines between nine patients with FS submitted to kinesiotherapy for 12 weeks and ten patients not submitted to kinesiotherapy. The kinesiotherapy was composed by self-stretching followed by a resistance training for upper and lower limbs. The protocol was carried out in three sections of eight to ten repetitions with 70% of the maximum load measured by test maximum of ten repetitions. After strengthening period patients performed a passive stretching. The training sessions lasted 50 min and were performed 3 times a week at least 12 weeks. Cytokines and chemokines were assessed in plasma using enzyme-linked immunosorbent assay and/or cytometric bead array. Patients with FS were being kinesiotherapy presented minors levels of interferon-γ, interleukin (IL)-17, IL-22, and IL-15 when compared to those not submitted to kinesiotherapy. No differences were observed for the detection of the chemokines chemokine ligand (CCL)-2, CCL-3, CCL-5, CCL-11, C-X-C motif chemokine 8 (CXCL-8), and CXCL-10. These results suggest that kinesiotherapy had a positive impact on inflammatory markers that are associated with disease worsening in FS.

Exposure to antibiotics affects saponin immersion induced immune stimulation and shift in microbial composition in zebrafish larvae

In the last decades, pollution of the environment by large scale use of antibiotics in agriculture and human medicine have led to increased antimicrobial resistance in both the environment and the host animal microbiome. Disturbances in the host microbiome can result in impaired immunity and reduced resilience of aquaculture species. Here, we investigated whether environmentally measured levels of the commonly used antibiotics ciprofloxacin and oxytetracycline influences the host microbiome and susceptibility toward saponin-induced immune stimulation in larval zebrafish. Firstly, neutrophil and macrophage reporter zebrafish larvae were exposed to different concentrations of soy saponin by immersion. A dose-dependent increase in neutrophil presence in the intestinal area was observed together with increased expression of immune genes il1b, tnfa, il22 and mmp9. To investigate the effect of antibiotics, larval zebrafish were immersed in ciprofloxacin or oxytetracycline in the presence or absence of a low dose of saponin. In vivo imaging revealed that antibiotic treatment did not reduce the number of neutrophils that were recruited to the intestinal area upon saponin exposure, although it did tend to lower pro-inflammatory cytokine levels. Microbial sequencing of whole larvae revealed that exposure to a low dose of saponin already shifted the microbial composition. The combination of oxytetracycline and saponin significantly increased α-diversity compared to the controls. In conclusion, the current study provides evidence that the combination of low levels of antibiotics with low levels of anti-nutritional factors (saponin) can induce inflammatory phenotypes and can modify the microbiota, which might lead to altered disease susceptibility.

Biodegradable Nanoparticles Containing Antigen and Vitamin D3 Efficiently Induce Antigen-specific Immune Suppression

Abstract Biodegradable poly(D,L-lactide-co-glycolide) (PLGA) nanoparticles (NPs) encapsulated with antigens can efficiently deliver the antigens to antigen-presenting cells such as dendritic cells (DCs). Active form of vitamin D, 1α,25-dihydroxyvitamin D3 (VD3), is known to have various immunosuppressive effects. Encapsulation of VD3 within NPs would enhance the delivery of VD3 to APCs, while preventing the potential systemic side effects of VD3. In this study, we examined the effects of PLGA NPs encapsulated with ovalbumin (OVA) and VD3. PLGA NPs containing OVA and VD3 (NP[OVA+VD3]) were prepared by W1/O/W2 double emulsion solvent evaporation method. Bone marrow-derived DCs treated with NP[OVA+VD3] were decreased in the expression of co-stimulatory molecules, and produced higher levels of immunosuppressive cytokines, while producing lower levels of pro-inflammatory cytokines, compared with DCs treated with NP[OVA]. Addition of NP[OVA+VD3] to allogeneic MLR reduced the proliferation of allogenic T cells. In addition, NP[OVA+VD3]-treated DCs efficiently generated CD4+CD25+Foxp3+Treg cells from CD4+CD25− T cells. Furthermore, mice injected i.v. with NP[OVA+VD3] were suppressed in inducing OVA-specific cytotoxic T cells. These results show that phagocytic delivery of antigen and VD3 to APCs using biodegradable NPs efficiently suppresses antigen-specific immune responses.