RESUMO
BACKGROUND: Excretory-secretory products released by Echinococcus granulosus protoscoleces (EgPSC-ESPs) are well-known to regulate T cell responses. However, their direct influence on the differentiation of B cell subsets remains largely elusive. This study investigated the effects of EgPSC-ESPs on the differentiation of IL-10-producing B cells (B10), and explored the possible role of Toll-like receptor 2 (TLR-2) signaling in this process. RESULTS: In comparison to phosphate buffered saline (PBS), B cells exposed to the excretory-secretory products (ESPs) generated higher percentages of B10 cells, with higher expression of IL-10 mRNA, and larger amount of IL-10 production, which were in a dose dependent way. The mRNA and protein expression of TLR-2 in the ESPs-stimulated B cells were significantly higher than those in PBS, which was consistent to the results in B cells isolated from EgPSC infected mice. Moreover, TLR-2-/- B cells in response to ESPs stimulation expressed lower levels of IL-10 mRNA and produced undetectable IL-10 in comparison to those in normal B cells. In addition, Phosphatase and tensin homolog deleted on chromosome ten/AKT/Phosphatidylinositol-3 kinase (PTEN/AKT/PI3K) pathway was activated in ESPs-treated B cells, which was also dependent on TLR-2 signaling. Pam3CSK4, the agonist of TLR-2, could mock the effects of ESPs on the expression of PTEN, AKT and PI3K. CONCLUSION: Overall, this study revealed that TLR-2 signaling was required for B10 induction mediated by EgPSC-ESPs, which might be an immunomodulatory target against the parasite infection.
Assuntos
Antígenos de Helmintos/imunologia , Subpopulações de Linfócitos B/imunologia , Equinococose/imunologia , Echinococcus granulosus/imunologia , Interleucina-10/metabolismo , Receptor 2 Toll-Like/metabolismo , Animais , Interleucina-10/genética , Camundongos Endogâmicos C57BL , PTEN Fosfo-Hidrolase/metabolismo , Fosfatidilinositol 3-Quinase/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptor 2 Toll-Like/genéticaRESUMO
Objective: To investigate the phenotype and phagocytosis changes of the peritoneal macrophages (Mφ) in mice infected with the larval-stage Echinococcus granulosus, and explore the role of Mφ in the responses to parasite infection. Methods: Twenty-four female BALB/c mice (age of 6-8 weeks) were randomly assigned into control group and infection group (n=12 in each group). The mice in the infection group were intraperitoneally injected with 2 000 protoscoleces, while the control mice were injected with equal volume of PBS. Five months after infection, the peritoneal mononuclear cells were collected, and the percentage of Mφ and the expression of surface markers CD40, CD80, CD86, and major histocompatibility complex â ¡ (MHCâ ¡) were determined by flow cytometry. The absorbanceï¼A490 valueï¼ of Mφ at different concentrationsï¼1×106, 5×105, 1×105ï¼ was determined by the neutral red assay to evaluate the phagocytic ability of Mφ. Results: The Mφ constitutedï¼30.40±3.15ï¼% andï¼20.75±5.91ï¼% in mononuclear cells in the infection and the control groups, respectively. The percentages of Mφ expressing CD40, CD80, CD86, and MHC â ¡ wereï¼45.33±5.51ï¼%, ï¼61.00±10.61ï¼%, ï¼56.88±10.66ï¼% and ï¼27.00±3.82ï¼% in the infection group, which were all significantly higher than those in the control ï¼»ï¼41.43±6.19ï¼%, ï¼59.23±8.65ï¼%, ï¼10.91±1.82ï¼% and ï¼13.67±3.01%ï¼ï¼½ ï¼P<0.05ï¼. The A490 values of Mφ at 1×106, 5×105, 1×105 were 0.41±0.03ï¼ 0.24±0.05 and 0.16±0.01 in the infection group, which were significantly lower than those in the control ï¼0.61±0.15, 0.47±0.07 and 0.18±0.01ï¼ï¼P<0.01ï¼. Conclusion: The phagocytic ability of peritoneal Mφ is dramatically weakened after infection, but the expression of activation-associated surface markers is significantly up-regulated after infection.
Assuntos
Echinococcus granulosus , Macrófagos Peritoneais , Animais , Feminino , Citometria de Fluxo , Larva , Macrófagos , Camundongos , Camundongos Endogâmicos BALB C , Fagocitose , FenótipoRESUMO
Energy metabolism is the foundation of survival for all organisms, and mitochondria are the most important energy-supplying organelles in eukaryotic cells. However, the mitochondrial and energy/metabolism-related properties of cancer stem cells (CSCs), the stem cell-like subpopulation in tumor masses, remain unknown. In our study, we compared the masses of mitochondria and mitochondrial DNA (mtDNA), the mitochondrial membrane potential (Δψm), oxygen/glucose consumption, and the concentration of reactive oxygen species (ROS) and ATP between lung CSCs (LCSCs) and non-LCSCs. In addition, the change in features during differentiation was examined. Some mitochondrial and energy metabolism-related properties, such as perinuclear mitochondrial distribution, a lower quantity of mtDNA, higher Δψm, lower oxygen/glucose consumption, and lower intracellular concentrations of ROS and ATP, can be used as indicators of LCSCs.
Assuntos
Metabolismo Energético , Neoplasias Pulmonares/diagnóstico , Potencial da Membrana Mitocondrial , Mitocôndrias/metabolismo , Células-Tronco Neoplásicas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Trifosfato de Adenosina/metabolismo , Apoptose , Diferenciação Celular , DNA Mitocondrial/genética , Glucose/metabolismo , Humanos , Técnicas Imunoenzimáticas , Neoplasias Pulmonares/metabolismo , Oxigênio/metabolismo , Células Tumorais CultivadasRESUMO
This study aimed to investigate whether the classic hepatoprotective drug polyene phosphatidylcholine (PPC) regulates macrophage polarization and explores the potential role of TLR-2 in this process. In RAW264.7 macrophages and murine bone marrow-derived macrophages (BMDMs) stimulated by lipopolysaccharide (LPS), PPC significantly inhibited the production of IL-6, TNF-α, and the mRNA expression of M1-type macrophage markers. Consistently, PPC reduced the mRNA expression of several key enzymes in the pathways of glycolysis and lipid synthesis while increasing the expression of key enzymes associated with lipid oxidation. Moreover, blocking the glycolytic pathway using 2-deoxy-D-glucose (2-DG) significantly enhanced the anti-inflammatory effect of PPC. However, inhibition of lipid oxidation using GW9662 (an inhibitor of PPAR-γ) and GW6471 (an inhibitor of PPAR-α) abolished the anti-inflammatory effect of PPC. Interestingly, TLR-2 expression in macrophages was significantly downregulated after exposure to PPC. Moreover, pre-activation of TLR-2 hampered the anti-inflammatory effect of PPC. In addition, PPC did not inhibit the secretion of IL-6 and TNF-α in TLR-2-/- BMDMs that were activated by LPS. This was consistent with the increased expression of M1 markers and glycolytic and lipid synthesis enzymes but decreased lipid oxidation-related enzymes. These results showed that PPC inhibits the differentiation of M1-type macrophages, which was most likely related to TLR-2-mediated metabolic reprogramming.
Assuntos
Anti-Inflamatórios/farmacologia , Macrófagos/fisiologia , Fosfatidilcolinas/farmacologia , Receptor 2 Toll-Like/metabolismo , Animais , Diferenciação Celular , Reprogramação Celular , Feminino , Interleucina-6/metabolismo , Peroxidação de Lipídeos , Lipopolissacarídeos/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Células RAW 264.7 , Transdução de Sinais , Células Th1/imunologia , Receptor 2 Toll-Like/genética , Fator de Necrose Tumoral alfa/metabolismoRESUMO
Disordered glucose and lipid metabolism contributes to the progression of several liver diseases, while the upregulation of phosphatase and tensin homology deleted on chromosome ten (PTEN), a well-known tumour suppressor gene, can improve the condition through metabolic programming. This study first characterized the metabolic profiles and the involvement of PTEN in the hepatic fibrosis induced by Schistosoma japonicum (S. japonicum) to provide a novel clue for metabolism-targeted treatment. Compared with control mice, infected mice showed infiltrated immune cells in their livers, increased levels of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) and decreased glucose levels in their sera. The expression of key enzymes in the glycolytic pathway was significantly increased, and the expression of gluconeogenic genes was distinctly decreased. Moreover, the infection upregulated the hepatic expression of enzymes involved in fatty acid oxidation, which was consistent with the decreased number of lipid droplets in livers and the lowered levels of triglyceride in sera. Consistently, PTEN and its downstream signalling were significantly inhibited. In vitro, soluble egg antigen (SEA) downregulated the expression of PTEN in both the macrophage RAW264.7 cell line and the murine hepatocellular carcinoma HEP1-6 cell line, and induced a metabolic phenotype similar to the in vivo results. Overall, this study showed that S. japonicum infection induced the reprogramming of glucose and lipid metabolism in mice during the period of liver fibrosis and that SEA could act as a modulator to trigger such a metabolic switch in macrophages and hepatocytes. PTEN might play an essential role in mediating these metabolic reprogramming events.
Assuntos
Metabolismo dos Lipídeos/fisiologia , Cirrose Hepática/metabolismo , Metaboloma/fisiologia , Schistosoma japonicum/metabolismo , Esquistossomose Japônica/metabolismo , Animais , Linhagem Celular Tumoral , Feminino , Cirrose Hepática/microbiologia , Camundongos , Camundongos Endogâmicos BALB C , PTEN Fosfo-Hidrolase/metabolismo , Células RAW 264.7RESUMO
Parasitic infection improves metabolic homeostasis in "western diet"-induced obesity through the regulation of adipogenesis. However, the underlying mechanism is not yet fully understood. Using microarray analysis, this study investigated the long non-coding RNA (lncRNA) and messenger RNA (mRNA) profiles of subcutaneous adipose tissues from mice infected with Echinococcus granulosus protoscoleces. A total of 1052 mRNA (541 upregulated, 511 downregulated) and 220 lncRNA (126 upregulated, 94 downregulated) transcripts were differentially expressed (fold change ≥2, P < 0.05) in the infected subcutaneous adipose tissues. When compared with the control group, the infected mice showed a decrease in adipose tissue mass and a reduction in adipocyte size. Indirect calorimetry revealed the change in the energy metabolism after infection, characterized by a lower CO2 production and O2 consumption, a sharp decline in carbohydrate oxidation, and a slight increase in fat oxidation. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway analyses showed that the parasitic infection reprogrammed a complex metabolic network. Notably, "lipoxygenase" and "arginine and proline metabolism" pathways were significantly upregulated while "glycolysis," "tricarboxylic acid cycle," "de novo lipogenesis," and "lipid droplet" pathways were dramatically downregulated. In addition, several key lncRNAs were associated with insulin resistance and adipocyte differentiation. Overall, the present study suggested that E. granulosus infection could enhance lipolysis. Thus, our findings provide novel insights into parasite-mediated metabolic homeostasis, and into the mechanism of hypertrophic adipocytes in obesity.
RESUMO
This study sought to investigate the anti-inflammatory effect of Polyene Phosphatidylcholine (PPC), a clinical drug that is used to treat hepatopathy, on lipopolysaccharide (LPS)-stimulated macrophages and on bovine collagen II-induced arthritis (CIA) rats. In stimulated primary and Raw264.7 macrophages by LPS, PPC significantly down-regulated the relative expression of mRNA such as IL-6, TNF-α, TLR-2, TLR-4, MyD88, and NF-κB while up-regulated IL-10 and TGF-ß expression. Moreover, the concentration of IL-6, TNF-α, IL-10, and TGF-ß in the cultured supernatants showed the similar tendency with their mRNA alterations. In addition, PPC could significantly inhibit the LPS-induced expression of MyD88 and NF-κB p65 in both mRNA and protein levels. These results suggest that PPC could down-regulate the LPS-stimulated inflammation in macrophages through TLR-2/TLR-4/MyD88/NF-κB pathway in vitro. Furthermore, to explore its effects in vivo, PPC was administrated to CIA rats. In comparison to CIA group, PPC-treated rats showed decreased arthritis score and osteopenia. Besides, PPC exhibited its ability to alleviate the degree of synovial hyperplasia, inflammatory cell infiltration, and destruction of cartilage and bone, thus remarkably improving the condition of CIA rats. In short, this study demonstrated that PPC had the potential to be an anti-inflammatory drug to treat inflammatory disorders such as rheumatoid arthritis.
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The aim of the present study was to predict and analyze the secondary structure, and B and T cell epitopes of Echinococcus granulosus antigen 5 (Ag5) using online software in order to investigate its immunogenicity and preliminarily evaluate its potential as an effective antigen peptide vaccine for cystic echinococcosis. The PortParam program was used to analyze molecular weight, the theoretical isoelectric point, instability index and other physicochemical properties. The secondary structure of the Ag5 protein was predicted using Self-Optimized Prediction method With Alignment and the tertiary structure of the Ag5 protein was predicted using 3DLigandSite together with Center for Biological Sequence Analysis Prediction Servers. Furthermore, the Immune Epitope Database software was used to predict B cell epitopes, and T cell epitopes were predicted with the BioInformatics and Molecular Analysis Section and SYFPEITHI programs. The results demonstrated that α-helixes, ß-turns, random coils and extended strands account for 23.35, 10.95, 41.32, and 24.38% of the secondary structure of the Ag5 protein, respectively. Ten potential B cell epitopes of Ag5 were identified as the amino acids sequences 27-39, 70-80, 117-130, 146-168, 250-262, 284-293, 339-349, 359-371, 403-412 and 454-462, and seven potential T cell epitopes were identified as the amino acid sequences 52-60, 57-65, 182-190, 231-239, 273-281, 318-326 and 467-475. Thus, ten B cell epitopes and seven T cell epitopes were identified on Ag5, suggesting the strong immunogenicity of this protein, which could be applied to design antigen peptide vaccines for echinococcosis.
RESUMO
BACKGROUND: Excretory-secretory products (ESPs) released by helminths are well-known to regulate T cell responses in the host. However, their direct influence in the differentiation of naïve T cells, and especially B cells, remains largely unknown. This study investigated the effects of Echinococcus granulosus protoscoleces ESPs (EgPSC-ESPs) on the differentiation of IL-10-producing B cells (B10), IL-17A-producing B cells (B17) and Th17 cells. METHODS: BALB/c mice injected with EgPSC were used to evaluate the in vivo profiles of B10, B17 and Th17 cells. In vitro purified CD19+ B and naïve CD4+ T cells were cultured in the presence of native, heat-inactivated or periodate-treated EgPSC-ESPs, and the differentiation of these cell subsets were compared. RESULTS: In contrast to the control group, infected mice showed higher frequencies of B10, B17 and Th17 cells, and higher levels of IL-10 and IL-17A in the sera. Interestingly, B17 cells were first identified to express CD19+CD1dhigh. In vitro, B cells cultured with native ESPs exhibited a higher percentage of B10 cells but lower percentage of B17 and Th17 cells compared to the PBS group. Moreover, the relative expression of IL-10 and IL-17A mRNA were consistent with the altered frequencies. However, ESPs subjected to heat-inactivation or periodate treatment exhibited an inverse effect on the induction of these cell subsets. CONCLUSIONS: Our findings indicate that ESPs released by EgPSC can directly regulate the differentiation of B10, B17 and Th17 cells, which appear to be heat-labile and carbohydrate-dependent.