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1.
J Med Microbiol ; 68(11): 1649-1654, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31609198

RESUMO

Myeloid C-type lectin receptors (CLRs) are innate immune recognition molecules that bind to microorganisms via their carbohydrate recognition domains. In this study, we utilized a library of CLRs that recognize fungal mannans. We used this library to screen against Pneumocystis carinii (Pc) homogenates or purified Pc major surface glycoprotein (Msg) present on Pneumocystis. The results demonstrated that all of the mammalian CLR hFc-fusions tested displayed significant interaction/binding with Pc organisms, and furthermore to isolated Msg. Highest Pc organism and Msg binding activities were with CLR members Mincle, Dectin-2, DC-SIGN and MCL. An immunofluorescence assay with the respective CLR hFc-fusions against whole Pc life forms corroborated these findings. Although some of these CLRs have been implicated previously as important for Pneumocystis pathogenesis (Dectin-1/Dectin-2/Mincle), this is the first analysis of head-to-head comparison of known fungal mannan binding CLR-hFc fusions with Pc. Lastly, heat treatment resulted in reducted CLR binding.


Assuntos
Proteínas Fúngicas/metabolismo , Lectinas Tipo C/metabolismo , Mananas/metabolismo , Glicoproteínas de Membrana/metabolismo , Infecções por Pneumocystis/metabolismo , Pneumocystis carinii/metabolismo , Humanos , Lectinas Tipo C/genética , Infecções por Pneumocystis/genética , Infecções por Pneumocystis/microbiologia , Pneumocystis carinii/genética , Ligação Proteica
2.
Chemistry ; 25(61): 13945-13955, 2019 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-31404475

RESUMO

The human macrophage galactose-type lectin (MGL), expressed on macrophages and dendritic cells (DCs), modulates distinct immune cell responses by recognizing N-acetylgalactosamine (GalNAc) containing structures present on pathogens, self-glycoproteins, and tumor cells. Herein, NMR spectroscopy and molecular dynamics (MD) simulations were used to investigate the structural preferences of MGL against different GalNAc-containing structures derived from the blood group A antigen, the Forssman antigen, and the GM2 glycolipid. NMR spectroscopic analysis of the MGL carbohydrate recognition domain (MGL-CRD, C181-H316) in the absence and presence of methyl α-GalNAc (α-MeGalNAc), a simple monosaccharide, shows that the MGL-CRD is highly dynamic and its structure is strongly altered upon ligand binding. This plasticity of the MGL-CRD structure explains the ability of MGL to accommodate different GalNAc-containing molecules. However, key differences are observed in the recognition process depending on whether the GalNAc is part of the blood group A antigen, the Forssman antigen, or GM2-derived structures. These results are in accordance with molecular dynamics simulations that suggest the existence of a distinct MGL binding mechanism depending on the context of GalNAc moiety presentation. These results afford new perspectives for the rational design of GalNAc modifications that fine tune MGL immune responses in distinct biological contexts, especially in malignancy.


Assuntos
Acetilgalactosamina/química , Lectinas Tipo C/metabolismo , Antígenos de Grupos Sanguíneos/química , Antígenos de Grupos Sanguíneos/metabolismo , Mapeamento de Epitopos , Humanos , Lectinas Tipo C/química , Lectinas Tipo C/genética , Ligantes , Simulação de Dinâmica Molecular , Ressonância Magnética Nuclear Biomolecular , Ligação Proteica , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/química , Proteínas Recombinantes/isolamento & purificação
3.
Arch Virol ; 164(11): 2793-2797, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31440811

RESUMO

The DC-SIGN glycoprotein is responsible for the initial adhesion of dengue virus (DENV) to immune cells by the carbohydrate recognition domain (CRD). There are thirteen soluble and membrane-bound DC-SIGN isoforms, but the role of soluble isoforms in the DENV internalization process is not known. Five isoforms with an altered or absent CRD were identified, and three different soluble isoforms were used to confirm the interactions with mannose residues. The results show the loss of binding ability of one soluble isoform and binding ability of two of them. All of them will be used to verify their role in the DENV internalization process.


Assuntos
Moléculas de Adesão Celular/genética , Moléculas de Adesão Celular/metabolismo , Vírus da Dengue/metabolismo , Lectinas Tipo C/genética , Lectinas Tipo C/metabolismo , Manose/metabolismo , Receptores de Superfície Celular/genética , Receptores de Superfície Celular/metabolismo , Ligação Viral , Internalização do Vírus , Sequência de Aminoácidos , Sequência de Bases , Dengue/virologia , Vírus da Dengue/genética , Ligantes , Ligação Proteica/genética , Isoformas de Proteínas/genética
4.
Cancer Immunol Immunother ; 68(9): 1455-1465, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31444606

RESUMO

Macrophages have been shown to infiltrate a wide range of malignancies and are often considered to promote tumour survival, growth and spread. However, the source and behaviour of discrete tumour-associated macrophage populations are still poorly understood. Here we show a novel method for the rational development of bone marrow-derived monocytes appropriate for the study of processes which involve the contribution of circulating inflammatory monocytes. We have shown that in response to tumour-conditioned medium, these cells upregulate CD206 and CD115, markers traditionally associated with M2-type macrophages. Treated cells show reduced capacity for cytokine secretion but significantly impact CD4+ and CD8+ T-cell proliferation and polarization. Coculture with conditioned bone marrow-derived monocytes significantly reduced CD4+ T-cell proliferation but increased CD8+ T-cell proliferation and granzyme B expression with significant induction of IFNγ secretion by both CD4+ and CD8+ T cells, indicating that these cells may have a role in promoting anti-cancer immunity.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Macrófagos/imunologia , Melanoma/imunologia , Monócitos/imunologia , Neoplasias Cutâneas/imunologia , Animais , Células da Medula Óssea/citologia , Diferenciação Celular , Técnicas de Cocultura , Meios de Cultivo Condicionados/metabolismo , Citocinas/metabolismo , Citotoxicidade Imunológica , Lectinas Tipo C/metabolismo , Ativação Linfocitária , Lectinas de Ligação a Manose/metabolismo , Melanoma Experimental , Camundongos , Camundongos Endogâmicos C57BL , Neoplasias Experimentais , Receptor de Fator Estimulador de Colônias de Macrófagos/metabolismo , Receptores de Superfície Celular/metabolismo , Células Th2/imunologia
5.
Nat Immunol ; 20(8): 1012-1022, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31263276

RESUMO

The plasma membrane tetraspan molecule MS4A4A is selectively expressed by macrophage-lineage cells, but its function is unknown. Here we report that MS4A4A was restricted to murine and human mononuclear phagocytes and was induced during monocyte-to-macrophage differentiation in the presence of interleukin 4 or dexamethasone. Human MS4A4A was co-expressed with M2/M2-like molecules in subsets of normal tissue-resident macrophages, infiltrating macrophages from inflamed synovium and tumor-associated macrophages. MS4A4A interacted and colocalized with the ß-glucan receptor dectin-1 in lipid rafts. In response to dectin-1 ligands, Ms4a4a-deficient macrophages showed defective signaling and defective production of effector molecules. In experimental models of tumor progression and metastasis, Ms4a4a deficiency in macrophages had no impact on primary tumor growth, but was essential for dectin-1-mediated activation of macrophages and natural killer (NK) cell-mediated metastasis control. Thus, MS4A4A is a tetraspan molecule selectively expressed in macrophages during differentiation and polarization, essential for dectin-1-dependent activation of NK cell-mediated resistance to metastasis.


Assuntos
Células Matadoras Naturais/imunologia , Lectinas Tipo C/metabolismo , Macrófagos/imunologia , Proteínas de Membrana/metabolismo , Metástase Neoplásica/imunologia , Neoplasias/imunologia , Animais , Diferenciação Celular/imunologia , Linhagem da Célula , Dexametasona/farmacologia , Humanos , Interleucina-4/metabolismo , Ativação Linfocitária/imunologia , Ativação de Macrófagos/imunologia , Macrófagos/citologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD , Metástase Neoplásica/prevenção & controle , Neoplasias/patologia
6.
Curr Top Microbiol Immunol ; 422: 1-30, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31278515

RESUMO

Melanins are a class of pigments that are ubiquitous throughout biology. They play incredibly diverse and important roles ranging from radiation protection to immune defense, camouflage, and virulence. Fungi have evolved to use melanin to be able to persist in the environment and within organisms. Fungal melanins are often located within the cell well and are able to neutralize reactive oxygen species and other radicals, defend against UV radiation, bind and sequester non-specific peptides and compounds, and produce a physical barrier that defends the cell. For this reason, melanized fungi are often well-suited to be human pathogens-melanin allows fungi to neutralize the microbicidal oxidative bursts of our innate immune system, bind and inactivate to antimicrobial peptides and enzymes, sequester antifungal pharmaceuticals, and create a shield to block immune recognition of the fungus. Due to the importance and pervasiveness of melanin in fungal virulence, mammalian immune systems have evolved antifungal strategies that involve directly detecting and binding to fungal melanins. Such strategies include the use of melanin-specific antibody responses and C-type lectins like the newly discovered melanin-specific MelLec receptor.


Assuntos
Fungos/metabolismo , Fungos/patogenicidade , Melaninas/metabolismo , Animais , Fungos/imunologia , Interações Hospedeiro-Patógeno/imunologia , Interações Hospedeiro-Patógeno/fisiologia , Humanos , Lectinas Tipo C/metabolismo , Melaninas/imunologia , Virulência
7.
Afr Health Sci ; 19(1): 1460-1466, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31148973

RESUMO

Background: Persistent antigenic stimulation due to repeated exposure to nickel may lead to chronic inflammation resulting in allergic contact dermatitis (ACD). Objectives: This study was performed to assess nickel induced immune activation among patients sensitized against nickel. Patients and Methods: A total of 35 patients (29 females and 6 males; mean age 36±9 years) with nickel contact dermatitis and 20 patch test negative healthy individuals (14 females and 6 males; mean age 29±7 years) were included in this study. Peripheral blood of patients and controls was incubated with nickel sulfate for 24 hours. Immune activation was assessed by CD69 up-regulation on T lymphocyte sub-sets by flow cytometry. Results: Base line expression of CD69 on CD8+ lymphocytes was higher among patients compared to controls (4.1±1.3%vs2.8±1.1%;p<0.009). There was no difference in proportions of CD±CD69+ cells between patients and controls (3.2±0.9%vs2.3±0.8%). Exposure to nickel induced expression of CD69 on a significantly higher proportion of CD4+ lymphocytes (22.1±6.2%) of the ACD patients compared to controls (2.8±2.5%;p<0.0001). Similarly nickel induced CD69 expression on a higher proportion of CD8+ lymphocytes (18.2±5.3%) from ACD patients compared to the controls (1.9±1.8%;p<0.0006). Conclusion: CD69 molecule appears to be an important regulator of immune response in nickel contact dermatitis.


Assuntos
Antígenos CD/metabolismo , Antígenos de Diferenciação de Linfócitos T/metabolismo , Linfócitos T CD4-Positivos/imunologia , Dermatite Alérgica de Contato/imunologia , Lectinas Tipo C/metabolismo , Níquel/efeitos adversos , Níquel/imunologia , Adulto , Alérgenos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/imunologia , Estudos de Casos e Controles , Dermatite Alérgica de Contato/diagnóstico , Feminino , Citometria de Fluxo , Humanos , Masculino , Pessoa de Meia-Idade , Níquel/farmacologia , Testes do Emplastro , Regulação para Cima , Adulto Jovem
8.
Cancer Immunol Immunother ; 68(8): 1223-1233, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31201473

RESUMO

Plasmacytoid dendritic cells (pDCs) are present in various primary and metastatic human neoplasms; however, their clinical significance in hepatocellular carcinoma (HCC) is unclear. In this study, we investigated the distribution, prognostic value, and potential function of pDCs in HCC patients undergoing curative resection. We performed immunohistochemical analyses of whole tumor sections from 224 patients to assess the expression of BDCA2, CD3, CD4, CD8, Foxp3, granzyme B, IL-17, and CD34. The findings were validated using tissue microarrays from another two independent cohorts totaling 841 HCC patients undergoing curative resection. Our results demonstrated that high numbers of BDCA2+ pDCs within tumors correlated with high alpha-fetoprotein levels, greater vascular invasion, advanced tumor-node-metastasis stage, shorter overall survival, and a higher recurrence rate. However, patient outcomes were not associated with pDCs in peritumoral stromal or nontumor tissues. Furthermore, an increase in intratumoral pDCs was associated with increased intratumoral infiltration of Foxp3+ regulatory T cells and IL-17-producing cells and correlated with tumor vascular density. Univariate and multivariate analyses revealed that the presence of intratumoral pDCs alone or in combination with regulatory T and/or IL-17-producing cells was an independent predictor of time to recurrence and overall survival. In conclusion, our study demonstrated that intratumoral infiltration by pDCs is a novel indicator for poor prognosis in patients with HCC, possibly through the induction of an immune tolerogenic and inflammatory tumor microenvironment comprising regulatory T and IL-17-producing cells. An assessment of the combination of these cells represents a superior predictor of patient outcome.


Assuntos
Carcinoma Hepatocelular/diagnóstico , Células Dendríticas/imunologia , Interleucina-17/metabolismo , Neoplasias Hepáticas/diagnóstico , Linfócitos T Reguladores/imunologia , Adulto , Idoso , Carcinoma Hepatocelular/imunologia , Carcinoma Hepatocelular/mortalidade , Progressão da Doença , Feminino , Seguimentos , Fatores de Transcrição Forkhead/metabolismo , Hepatectomia , Humanos , Lectinas Tipo C/metabolismo , Neoplasias Hepáticas/imunologia , Neoplasias Hepáticas/mortalidade , Masculino , Glicoproteínas de Membrana/metabolismo , Pessoa de Meia-Idade , Metástase Neoplásica , Prognóstico , Receptores Imunológicos/metabolismo , Análise de Sobrevida , alfa-Fetoproteínas/metabolismo
9.
Int J Nanomedicine ; 14: 3203-3220, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31118632

RESUMO

Background: Tumor-associated macrophages (TAMs) are critical in tumor progression and metastasis. Selective targeting of TAMs holds great potential to ameliorate the immunosuppressive tumor microenvironment and enhance the efficacy of antitumor therapy. Various liposomes have been developed to target TAMs via cell-specific surface receptors either to deplete or re-educate TAMs. Since immuno-stimulation often initiates with the interaction of nanocarriers with the innate immunity cells such as macrophages, the intrinsic impact of drug-free liposomes on macrophage activation and polarization via cell interaction is one of the most critical issues in nanomedicine for promoting effective immunotherapy. Methods: In this study, conventional bare liposomes, PEGylated liposomes, and mannosylated liposomes were developed and the cytotoxicity, cellular internalization, immunostimulatory activity, targeting efficiency, antitumor efficacy, and mechanism were evaluated in vitro and in vivo. Results: All liposomes displayed an ideal particle size, good biocompatibility, and controlled release behavior. Mannosylated liposomes exhibited superior in vitro cellular internalization and tumor spheroid penetration with the aid of the mannose receptor-mediated TAMs-targeting effects. In particular, mannosylated liposomes promoted the polarization of both M0 and M2 to the M1 phenotype by enhancing the expression ratio of CD86/CD206 in vitro. Of note, mannosylated liposomes could inhibit G422 glioma tumor growth, which may be attributed to the polarization of TAMs, as evidenced by the reduction in expression level of the TAMs surface marker. Conclusion: These results indicate the potential value of mannosylated liposomes in the design of a rational delivery system to enhance the antitumor immune efficacy of immunomodulators by inducing a shift from the M2 to the M1 phenotype.


Assuntos
Polaridade Celular , Lectinas Tipo C/metabolismo , Macrófagos/metabolismo , Macrófagos/patologia , Lectinas de Ligação a Manose/metabolismo , Neoplasias/patologia , Receptores de Superfície Celular/metabolismo , Adjuvantes Imunológicos/farmacologia , Animais , Morte Celular , Linhagem Celular Tumoral , Proliferação de Células , Cumarínicos/química , Liberação Controlada de Fármacos , Endocitose , Feminino , Humanos , Lipossomos , Macrófagos/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos ICR , Fosfatidiletanolaminas/química , Polietilenoglicóis/química , Células RAW 264.7 , Esferoides Celulares/metabolismo , Esferoides Celulares/patologia , Tiazóis/química , Distribuição Tecidual , Microambiente Tumoral
10.
Ann Otol Rhinol Laryngol ; 128(6_suppl): 45S-51S, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31092026

RESUMO

OBJECTIVES: The aim of this study was to investigate the effect of regulatory T cells (Tregs) on B-cell immune responses against outer membrane protein (OMP) from nontypeable Haemophilus influenzae (NTHi) in vitro, to clarify its exact mechanism from an immunologic standpoint. METHODS: Mice were vaccinated intranasally with OMP to induce OMP-specific immune responses in the nasal mucosa. Mononuclear cells (MNCs) were collected from the nasal mucosa, and Tregs and helper T (Th) cells were isolated separately from the spleens of those mice. Three different cell culture groups were allocated: MNCs cocultured with Tregs, MNCs cocultured with Th cells, and MNCs cultured alone. At 24 and 72 hours after cell culture, the concentrations of various cytokines and antibodies in culture supernatants were measured to assess the effects of Tregs and Th cells on B-cell responses. Cytokine levels and specific anti-OMP antibody levels in culture media were determined using enzyme-linked immunosorbent assay. CD69 or CD80 expression on B220-positive cells was detected using flow cytometric analysis. RESULTS: Th1 and Th2 cytokine concentrations were significantly elevated in the 3 groups incubated with OMP from 24 to 72 hours. Additionally, interleukin-10 levels were significantly higher in the Treg and Th groups than in the control group. Levels of OMP-specific immunoglobulin A did not differ significantly among the groups. The ratios of CD69+B220+ B2 cells were nearly the same in the 3 groups; however, the ratio of CD80+B220+ B2 cells was higher in the control group than in the Treg and Th groups during incubation. CONCLUSIONS: Tregs and Th cells did not affect OMP-specific immunoglobulin A production in this study. However, these cells may partially inhibit B-cell functions, such as T-cell activation. These inhibitory effects may be related to interleukin-10.


Assuntos
Linfócitos B/fisiologia , Haemophilus influenzae/imunologia , Linfócitos T Reguladores/fisiologia , Animais , Antígenos CD/metabolismo , Antígenos de Diferenciação de Linfócitos T/metabolismo , Antígeno B7-1/metabolismo , Proteínas da Membrana Bacteriana Externa , Técnicas de Cultura de Células , Citocinas/metabolismo , Imunidade nas Mucosas , Lectinas Tipo C/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Mucosa Nasal
11.
Vet Res Commun ; 43(2): 115-122, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30989431

RESUMO

Dendritic cells (DC) are important antigen-presenting cells and are among the least characterized immune cells in the chicken. In order to obtain chicken DC, current protocols require isolation of bone marrow myeloid progenitor cells and induction of DC differentiation with supplemental cytokines or negative selection of splenic cell preparations. Chicken peritoneal exudate cells (PEC) have traditionally been a source of various immune cells for ex vivo studies, primarily to investigate heterophils and macrophages. In this study, we observe the presence of CD205+ PEC populations, a marker of DC, as an additional resource to isolate and study chicken primary DCs. A panel of monoclonal antibodies was developed against the chicken CD205 DC marker and used to isolate CD205+ DC from the PEC population using magnetic bead cell sorting. This study reports the development of new anti-CD205 monoclonal antibodies as a reagent for chicken DC research, as well as PEC as a potential source of CD205+ DC for ex vivo studies in the chicken.


Assuntos
Antígenos CD/metabolismo , Separação Celular/veterinária , Galinhas/imunologia , Células Dendríticas/citologia , Lectinas Tipo C/metabolismo , Antígenos de Histocompatibilidade Menor/metabolismo , Receptores de Superfície Celular/metabolismo , Animais , Anticorpos Monoclonais/metabolismo , Células Dendríticas/imunologia , Sefarose/imunologia
12.
Cell Physiol Biochem ; 52(5): 1003-1016, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30977985

RESUMO

BACKGROUND/AIMS: The composition of the extracellular matrix (ECM) in the central nervous system (CNS) has several features that make it unique. For instance, it is remarkable for the presence of proteoglycans such as versican, brevican, and neurocan, some of which have been identified as substrates of different members of the ADAMTS family of secreted metalloproteases. Previous studies have associated ADAMTSs with the repair of the CNS, including recovery following degradation of glial scar tissue and the stimulation of axonal growth after brain injury. However, the involvement of ADAMTSs in diseases of the CNS is complex and not understood fully, and a current challenge is unraveling the precise roles of these metalloproteases in the brain. METHODS: ADAMTS12 and neurocan gene expression was examined by quantitative PCR. Western blot analysis was employed to detect ADAMTS12 and neurocan protein expression in cell lines, and immunostaining techniques were used to detect neurocan in mouse brain tissues. Neurocan cleavage using recombinant ADAMTS1, ADAMTS4, ADAMTS5, and ADAMTS12 metalloproteases was evaluated by western blotting. Cell adhesion and migration were assessed using uncoated culture dishes or dishes coated with Matrigel or ECM components. RESULTS: We identified neurocan as a novel component of brain ECM that can be cleaved by ADAMTS12. In addition, we showed that neurocan cleavage by ADAMTS12 altered the adhesive properties of the human neuroglioma H4 cell line. Moreover, immunohistochemical analysis of Adamts12-deficient mice revealed the significant accumulation of neurocan in the brain of neonatal mice. CONCLUSION: Overall, our results suggest that ADAMTS12 could be involved in the repair of the CNS through its ability to degrade neurocan. Moreover, it can be inferred that alterations in neurocan degradation processes could be associated with the pathogenesis of neurological disorders.


Assuntos
Proteínas ADAMTS/biossíntese , Proteínas ADAMTS/metabolismo , Proteoglicanas de Sulfatos de Condroitina/metabolismo , Doenças dos Nervos Cranianos/metabolismo , Lectinas Tipo C/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Proteoglicanas/metabolismo , Proteólise , Proteínas ADAMTS/genética , Animais , Adesão Celular , Linhagem Celular Tumoral , Movimento Celular , Proteoglicanas de Sulfatos de Condroitina/genética , Doenças dos Nervos Cranianos/genética , Doenças dos Nervos Cranianos/patologia , Regulação da Expressão Gênica , Humanos , Lectinas Tipo C/genética , Camundongos , Proteínas do Tecido Nervoso/genética , Proteoglicanas/genética
13.
Science ; 364(6438)2019 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-31023895

RESUMO

Metabolic health depends on the capacity of adipose tissue progenitor cells to undergo de novo adipogenesis. The cellular hierarchy and mechanisms governing adipocyte progenitor differentiation are incompletely understood. Through single-cell RNA sequence analyses, we show that the lineage hierarchy of adipocyte progenitors consists of distinct mesenchymal cell types that are present in both mouse and human adipose tissues. Cells marked by dipeptidyl peptidase-4 (DPP4)/CD26 expression are highly proliferative, multipotent progenitors. During the development of subcutaneous adipose tissue in mice, these progenitor cells give rise to intercellular adhesion molecule-1 (ICAM1)/CD54-expressing (CD54+) committed preadipocytes and a related adipogenic cell population marked by Clec11a and F3/CD142 expression. Transforming growth factor-ß maintains DPP4+ cell identity and inhibits adipogenic commitment of DPP4+ and CD142+ cells. Notably, DPP4+ progenitors reside in the reticular interstitium, a recently appreciated fluid-filled space within and between tissues, including adipose depots.


Assuntos
Adipócitos/citologia , Adipogenia , Tecido Adiposo/citologia , Células-Tronco Mesenquimais/citologia , Adipócitos/enzimologia , Animais , Dipeptidil Peptidase 4/metabolismo , Fatores de Crescimento de Células Hematopoéticas/metabolismo , Humanos , Molécula 1 de Adesão Intercelular/metabolismo , Lectinas Tipo C/metabolismo , Células-Tronco Mesenquimais/enzimologia , Camundongos , Análise de Sequência de RNA , Análise de Célula Única , Tromboplastina/metabolismo , Fator de Crescimento Transformador beta/metabolismo
14.
Mediators Inflamm ; 2019: 1919538, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31007601

RESUMO

Macrophages are key immune system cells involved in inflammatory processes. Classically activated (M1) macrophages are characterized by strong antimicrobicidal properties, whereas alternatively activated (M2) macrophages are involved in wound healing. Severe inflammation can induce postoperative complications during the perioperative period. Invasive surgical procedures induce polarization to M1 macrophages and associated complications. As perioperative management, it is an important strategy to regulate polarization and functions of macrophages during inflammatory processes. Although propofol has been found to exhibit anti-inflammatory activities in monocytes and macrophages, it is unclear whether propofol regulates the functions of M1 and M2 macrophages during inflammatory processes. This study therefore investigated the effects of propofol on human macrophage polarization. During M1 polarization, propofol suppressed the production of IL-6 and IL-1ß but did not affect TNF-α production. In contrast, propofol did not affect the gene expression of M2 markers, such as IL-10, TGF-ß, and CD206, during M2 polarization. Propofol was similar to the GABAA agonist muscimol in inducing nuclear translocation of nuclear factor-E2-related factor 2 (Nrf2) and inhibiting IL-6 and IL-1ß, but not TNF-α, production. Knockdown of Nrf2 using siRNA significantly reduced the effect of propofol on IL-6 and IL-1ß production. These results suggest that propofol prevents inflammatory responses during polarization of human M1 macrophages by suppressing the expression of IL-6 and IL-1ß through the GABAA receptor and the Nrf2-mediated signal transduction pathway.


Assuntos
Citocinas/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Células Cultivadas , Humanos , Interleucina-10/metabolismo , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Lectinas Tipo C/metabolismo , Lectinas de Ligação a Manose/metabolismo , Muscimol/farmacologia , Fator 2 Relacionado a NF-E2/genética , Propofol/farmacologia , Receptores de Superfície Celular/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
15.
PLoS Pathog ; 15(3): e1007633, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30875408

RESUMO

Memory CD8+ T cells in the circulation rapidly infiltrate non-lymphoid tissues following infection and provide protective immunity in an antigen-specific manner. However, the subsequent fate of memory CD8+ T cells after entering non-lymphoid tissues such as the skin during a secondary infection is largely unknown. Furthermore, because expression of CD62L is often used to identify the central memory (TCM) CD8+ T cell subset, uncoupling the physical requirement for CD62L-mediated lymph node homing versus other functional attributes of TCM CD8+ T cells remains unresolved. Here, we show that in contrast to naïve CD8+ T cells, memory CD8+ T cells traffic into the skin independent of CD62L-mediated lymph node re-activation and provide robust protective immunity against Vaccinia virus (VacV) infection. TCM, but not effector memory (TEM), CD8+ T cells differentiated into functional CD69+/CD103- tissue residents following viral clearance, which was also dependent on local recognition of antigen in the skin microenvironment. Finally, we found that memory CD8+ T cells expressed granzyme B after trafficking into the skin and utilized cytolysis to provide protective immunity against VacV infection. Collectively, these findings demonstrate that TCM CD8+ T cells become cytolytic following rapid infiltration of the skin to protect against viral infection and subsequently differentiate into functional CD69+ tissue-residents.


Assuntos
Linfócitos T CD8-Positivos/metabolismo , Memória Imunológica/fisiologia , Pele/imunologia , Animais , Antígenos CD/metabolismo , Antígenos CD/fisiologia , Antígenos de Diferenciação de Linfócitos T/metabolismo , Antígenos de Diferenciação de Linfócitos T/fisiologia , Linfócitos T CD8-Positivos/virologia , Feminino , Selectina L/metabolismo , Lectinas Tipo C/metabolismo , Lectinas Tipo C/fisiologia , Linfonodos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pele/virologia , Subpopulações de Linfócitos T/metabolismo , Subpopulações de Linfócitos T/fisiologia , Vírus Vaccinia/imunologia , Vírus Vaccinia/patogenicidade
16.
J Immunol Res ; 2019: 1529189, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30882002

RESUMO

Paracoccidioidomycosis (PCM), a systemic mycosis endemic in Latin America, occurs after inhalation of mycelial components of Paracoccidioides spp. When the fungus reaches the lungs and interacts with the alveolar macrophages and other cells, phagocytic cells such as neutrophils and monocytes are immediately recruited to the injured site. The interaction between surface molecules of pathogens and homologous receptors, present on the surface membrane of phagocytes, modulates the innate immune cell activation. Studies have shown the importance of fungal recognition by the Dectin-1 receptor, which can induce a series of cellular protective responses against fungi. The objective of the present study was to evaluate Dectin-1 receptor expression and the effector mechanisms of human monocytes and neutrophils activated or not with different cytokines, such as IFN-γ, TNF-α, and GM-CSF, followed by the challenge with Paracoccidioides brasiliensis (P. brasiliensis or Pb265). Therefore, analysis of Dectin-1 receptor expression was done by flow cytometry whereas the effector mechanisms were evaluated by fungal recovery by colony-forming unit (CFU) counting and hydrogen peroxide (H2O2) production. Our results showed that, after treatment with IFN-γ, TNF-α, and GM-CSF and challenge with Pb265, cells, especially monocytes, demonstrated an increase in Dectin-1 expression. Both types of cells treated with the cytokines exhibited a decreased fungal recovery and, conversely, an increased production of H2O2. However, when cultures were treated with an anti-Dectin-1 monoclonal antibody, to block the P. brasiliensis binding, a decrease in H2O2 production and an increase in fungal recovery were detected. This effect was observed in all cultures treated with the specific monoclonal antibody. These results show the involvement of the Dectin-1 receptor in fungal recognition and its consequent participation in the induction of the killing mechanisms against P. brasiliensis.


Assuntos
Citocinas/farmacologia , Lectinas Tipo C/metabolismo , Paracoccidioidomicose/imunologia , Fagócitos/imunologia , Contagem de Colônia Microbiana , Feminino , Fator Estimulador de Colônias de Granulócitos e Macrófagos/farmacologia , Humanos , Peróxido de Hidrogênio/análise , Interferon gama/farmacologia , Lectinas Tipo C/genética , Masculino , Monócitos/efeitos dos fármacos , Monócitos/imunologia , Neutrófilos/efeitos dos fármacos , Neutrófilos/imunologia , Paracoccidioides , Fagócitos/efeitos dos fármacos
17.
Nat Commun ; 10(1): 1424, 2019 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-30926808

RESUMO

The drivers and the specification of CD4+ T cell differentiation in the tumor microenvironment and their contributions to tumor immunity or tolerance are incompletely understood. Using models of pancreatic ductal adenocarcinoma (PDA), we show that a distinct subset of tumor-infiltrating dendritic cells (DC) promotes PDA growth by directing a unique TH-program. Specifically, CD11b+CD103- DC predominate in PDA, express high IL-23 and TGF-ß, and induce FoxP3neg tumor-promoting IL-10+IL-17+IFNγ+ regulatory CD4+ T cells. The balance between this distinctive TH program and canonical FoxP3+ TREGS is unaffected by pattern recognition receptor ligation and is modulated by DC expression of retinoic acid. This TH-signature is mimicked in human PDA where it is associated with immune-tolerance and diminished patient survival. Our data suggest that CD11b+CD103- DC promote CD4+ T cell tolerance in PDA which may underscore its resistance to immunotherapy.


Assuntos
Células Dendríticas/imunologia , Interleucina-10/metabolismo , Interleucina-17/metabolismo , Neoplasias Pancreáticas/imunologia , Linfócitos T Reguladores/imunologia , Adenocarcinoma/genética , Adenocarcinoma/imunologia , Adenocarcinoma/patologia , Animais , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/imunologia , Carcinoma Ductal Pancreático/patologia , Diferenciação Celular , Progressão da Doença , Fatores de Transcrição Forkhead , Regulação Neoplásica da Expressão Gênica , Humanos , Lectinas Tipo C/metabolismo , Camundongos Endogâmicos C57BL , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Fenótipo , Transdução de Sinais , Células Th17/imunologia , Receptor 2 Toll-Like/metabolismo , Tretinoína/metabolismo
18.
Mar Drugs ; 17(4)2019 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-30925723

RESUMO

Natural marine polysaccharides have demonstrated immune stimulatory effects in both mice and humans. Our previous study compared the ability of ascophyllan and fucoidan to activate human and mouse dendritic cells (DCs). In this study, we further examined the effect of ascophyllan on the activation of mouse natural killer (NK) cells in vivo and in vitro and compared it to that of fucoidan, a well-studied natural marine polysaccharide. Specifically, administration of ascophyllan to C57BL/6 mice increased the number of NK cells in the spleen when compared to the number in PBS-treated mice. Moreover, the number of IFN-γ-producing NK cells and expression of CD69 were markedly upregulated by ascophyllan treatment. Ascophyllan treatment also induced IFN-γ production and CD69 upregulation in isolated NK cells, but did not promote cell proliferation. Finally, ascophyllan treatment increased the cytotoxicity of NK cells against Yac-1 cells. The effects of ascophyllan on NK cell activation were considerably stronger than those of fucoidan. These data demonstrated that ascophyllan promotes NK cell activation both in mice and in vitro, and its stimulatory effect on NK cells is stronger than that of fucoidan.


Assuntos
Adjuvantes Imunológicos/farmacologia , Células Matadoras Naturais/efeitos dos fármacos , Células Matadoras Naturais/imunologia , Polissacarídeos/farmacologia , Animais , Antígenos CD/metabolismo , Antígenos de Diferenciação de Linfócitos T/metabolismo , Ascophyllum/química , Proliferação de Células/efeitos dos fármacos , Testes Imunológicos de Citotoxicidade , Interferon gama/metabolismo , Células Matadoras Naturais/citologia , Lectinas Tipo C/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Baço/citologia , Baço/efeitos dos fármacos , Células Tumorais Cultivadas
19.
Fish Shellfish Immunol ; 88: 266-271, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30849499

RESUMO

The normal microbiota plays a key role in the health of host, but little is known of how the fish immune system recognizes and responds to indigenous bacteria/probiotics. Our previous studies have showed that heat-inactivated indigenous Bacillus pumilus SE5 activate the TLR2 signaling pathways and modulate the intestinal microbiota in grouper (Epinephelus coioides), suggesting microbial-associated molecular patterns (MAMPs) involved. In this study, whole cell wall (CW) and two possible MAMPs, peptidoglycan (PG) and lipoteichoic acid (LTA) have been extracted from B. pumilus SE5 and their effects on intestinal immune related genes expression and microbiota were evaluated in a 60 days feeding trial. Significantly elevated expression of TLR1, TLR2, TLR5 and MyD88 was observed in fish fed the CW, PG and LTA containing diets, and the highest expression was observed in groups PG and LTA. At the same time, significantly upregulated expression of antimicrobial effectors, such as antimicrobial peptides (epinecidin-1, hepcidin-1 and ß-defensin), C-type Lectin and IgM was observed in fish fed PG and LTA containing diets. This induced activation of intestinal immunity was consistent with the microbiota data showing that CW, PG and LTA originated from SE5 modulated the overall structure of intestinal microbiota, and the relative abundance of potentially pathogenic Vibrio decreased significantly while beneficial Lactobacillus increased significantly in fish fed PG and LTA. In conclusion, both the PG and LTA originated from B. pumilus SE5 could activate TLRs/MyD88 signaling and expression of wide-ranging antibacterial effectors, and therefore shape the intestinal microbiota in grouper.


Assuntos
Bacillus pumilus/química , Bass/imunologia , Bass/microbiologia , Microbioma Gastrointestinal , Animais , Peptídeos Catiônicos Antimicrobianos/genética , Peptídeos Catiônicos Antimicrobianos/metabolismo , Bass/genética , Bass/metabolismo , Parede Celular , Expressão Gênica , Imunoglobulina M/genética , Imunoglobulina M/metabolismo , Intestinos/efeitos dos fármacos , Intestinos/imunologia , Intestinos/microbiologia , Lactobacillus , Lectinas Tipo C/genética , Lectinas Tipo C/metabolismo , Lipopolissacarídeos/farmacologia , Peptidoglicano/farmacologia , Ácidos Teicoicos/farmacologia , Vibrio
20.
Cell Prolif ; 52(3): e12584, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30834619

RESUMO

OBJECTIVES: Glioblastoma is the most common malignant glioma of all brain tumours. It is difficult to treat because of its poor response to chemotherapy and radiotherapy and high recurrence rate after treatment. The aetiology of glioblastoma is a result of disorders of multiple factors. Depending on cell signal transduction, these glioblastoma-associated factors lead to cell proliferation, differentiation and apoptosis. Therefore, investigation of the potential factors which involved in the development of glioblastoma could provide a new target for the treatment of glioblastoma. MATERIALS AND METHODS: We analysed the transcript expression of CLEC5A in glioblastoma by accessing The Cancer Genome Atlas (TCGA). qRT-PCR was performed to detect the RNA expression of genes in cells and tissues, and Western blot was used to measure the protein levels (Cyclin D1, Bcl-2, BAX, PCNA, MMP2, MMP9, Akt and Akt phosphorylation) in tissues and cells. Cell proliferation, migration, invasion, cycle and apoptosis were measured by CCK-8, transwell and flow cytometry assays, respectively. Ki67 level and lung metastasis were determined by immunochemistry and H&E staining. RESULTS: In this study, we found that CLEC5A was highly upregulated in glioblastoma compared to normal brain tissues, which had an opposite relation with the overall patient survival. Downregulation of CLEC5A could inhibit cell proliferation, migration and invasion via promoting apoptosis and G1 arrest. In contrast, overexpression of CLEC5A stimulated cell proliferation, migration and invasion. In addition, we found that CLEC5A level was positively correlated with Akt phosphorylation level. Akt inhibitor or agonist could reverse the modulation effects of CLEC5A in glioblastoma. Moreover, In vivo results suggested that inhibition of CLEC5A significantly reduced tumour size, weight, cell proliferation ability and lung metastasis via inhibition of phosphorylation Akt. CONCLUSION: Both in vitro and in vivo evidences supported that CLEC5A was involved in glioblastoma pathogenesis via regulation of PI3K/Akt pathway. Thus, CLEC5A might serve as a potential therapeutic target in the treatment of glioblastoma in the future.


Assuntos
Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Glioblastoma/genética , Glioblastoma/metabolismo , Lectinas Tipo C/genética , Lectinas Tipo C/metabolismo , Receptores de Superfície Celular/genética , Receptores de Superfície Celular/metabolismo , Animais , Apoptose , Neoplasias Encefálicas/patologia , Ciclo Celular , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Técnicas de Silenciamento de Genes , Glioblastoma/patologia , Xenoenxertos , Humanos , Lectinas Tipo C/antagonistas & inibidores , Masculino , Camundongos , Camundongos Nus , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/agonistas , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores de Superfície Celular/antagonistas & inibidores , Transdução de Sinais , Regulação para Cima
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