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1.
Infect Immun ; 88(2)2020 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-31611280

RESUMO

The pulmonary immune response protects healthy individuals against Pneumocystis pneumonia (PcP). However, the immune response also drives immunopathogenesis in patients who develop severe PcP, and it is generally accepted that optimal treatment requires combination strategies that promote fungal killing and also provide effective immunomodulation. The anti-inflammatory drug sulfasalazine programs macrophages for enhanced Pneumocystis phagocytosis and also suppresses PcP-related immunopathogenesis. Anti-Pneumocystis antibody opsonizes Pneumocystis organisms for greater phagocytosis and may also mask antigens that drive immunopathogenesis. Thus, we hypothesized that combining antibody and sulfasalazine would have the dual benefit of enhancing fungal clearance while dampening immunopathogenesis and allow the rescue of severe PcP. To model a clinically relevant treatment scenario in mice, therapeutic interventions were withheld until clear symptoms of pneumonia were evident. When administered individually, both passive antibody and sulfasalazine improved pulmonary function and enhanced Pneumocystis clearance to similar degrees. However, combination treatment with antibody and sulfasalazine produced a more rapid improvement, with recovery of body weight, a dramatic improvement in pulmonary function, reduced lung inflammation, and the rapid clearance of the Pneumocystis organisms. Accelerated fungal clearance in the combination treatment group was associated with a significant increase in macrophage phagocytosis of Pneumocystis Both passive antibody and sulfasalazine resulted in the suppression of Th1 cytokines and a marked increase in lung macrophages displaying an alternatively activated phenotype, which were enhanced by combination treatment. Our data support the concept that passive antibody and sulfasalazine could be an effective and specific adjunctive therapy for PcP, with the potential to accelerate fungal clearance while attenuating PcP-associated immunopathogenesis.


Assuntos
Anticorpos/imunologia , Fungos/efeitos dos fármacos , Fungos/imunologia , Pneumonia por Pneumocystis/tratamento farmacológico , Pneumonia por Pneumocystis/imunologia , Sulfassalazina/farmacologia , Animais , Anti-Inflamatórios/farmacologia , Citocinas/imunologia , Feminino , Fatores Imunológicos/imunologia , Imunomodulação/efeitos dos fármacos , Imunomodulação/imunologia , Imunoterapia/métodos , Inflamação/imunologia , Pulmão/efeitos dos fármacos , Pulmão/imunologia , Ativação de Macrófagos/efeitos dos fármacos , Ativação de Macrófagos/imunologia , Macrófagos Alveolares/efeitos dos fármacos , Macrófagos Alveolares/imunologia , Camundongos , Camundongos SCID , Fagocitose/efeitos dos fármacos , Fagocitose/imunologia
2.
Semin Oncol ; 46(4-5): 385-392, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31739997

RESUMO

There is no doubt that immunotherapy lies in the spotlight of current cancer research and clinical trials. However, there are still limitations in the treatment response in certain types of tumors largely due to the presence of the complex network of immunomodulatory and immunosuppressive pathways. These limitations are not likely to be overcome by current immunotherapeutic options, which often target isolated steps in immune pathways preferentially involved in adaptive immunity. Recently, we have developed an innovative anti-cancer immunotherapeutic strategy that initially elicits a strong innate immune response with subsequent activation of adaptive immunity in mouse models. Robust primary innate immune response against tumor cells is induced by toll-like receptor ligands and anti-CD40 agonistic antibodies combined with the phagocytosis-stimulating ligand mannan, anchored to a tumor cell membrane by biocompatible anchor for membrane. This immunotherapeutic approach results in a dramatic therapeutic response in large established murine subcutaneous tumors including melanoma, sarcoma, pancreatic adenocarcinoma, and pheochromocytoma. Additionally, eradication of metastases and/or long-lasting resistance to subsequent re-challenge with tumor cells was also accomplished. Current and future advantages of this immunotherapeutic approach and its possible combinations with other available therapies are discussed in this review.


Assuntos
Imunoterapia , Neoplasias/terapia , Imunidade Adaptativa , Animais , Antineoplásicos Imunológicos/farmacologia , Antineoplásicos Imunológicos/uso terapêutico , Terapia Combinada , Humanos , Sistema Imunitário/imunologia , Sistema Imunitário/metabolismo , Imunidade Inata , Imunomodulação , Imunoterapia/métodos , Ligantes , Neoplasias/etiologia , Neoplasias/metabolismo , Neoplasias/patologia , Fagocitose/efeitos dos fármacos , Fagocitose/imunologia , Receptores Toll-Like/metabolismo , Resultado do Tratamento , Microambiente Tumoral/efeitos dos fármacos , Microambiente Tumoral/genética , Microambiente Tumoral/imunologia
4.
Int J Mol Sci ; 20(19)2019 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-31597355

RESUMO

Macrophages are highly plastic and dynamic cells that exert much of their function through phagocytosis. Phagocytosis depends on a coordinated, finely tuned, and compartmentalized regulation of calcium concentrations. We examined the role of mitochondrial calcium uptake and mitochondrial calcium uniporter (MCU) in macrophage polarization and function. In primary cultures of human monocyte-derived macrophages, calcium uptake in mitochondria was instrumental for alternative (M2) macrophage polarization. Mitochondrial calcium uniporter inhibition with KB-R7943 or MCU knockdown, which prevented mitochondrial calcium uptake, reduced M2 polarization, while not affecting classical (M1) polarization. Challenging macrophages with E. coli fragments induced spikes of mitochondrial calcium concentrations, which were prevented by MCU inhibition or silencing. In addition, mitochondria remodelled in M2 macrophages during phagocytosis, especially close to sites of E. coli internalization. Remarkably, inhibition or knockdown of MCU significantly reduced the phagocytic capacity of M2 macrophages. KB-R7943, which also inhibits the membrane sodium/calcium exchanger and Complex I, reduced mitochondria energization and cellular ATP levels, but such effects were not observed with MCU silencing. Therefore, phagocytosis inhibition by MCU knockdown depended on the impaired mitochondrial calcium buffering rather than changes in mitochondrial and cellular energy status. These data uncover a new role for MCU in alternative macrophage polarization and phagocytic activity.


Assuntos
Cálcio/metabolismo , Ativação de Macrófagos/imunologia , Macrófagos/imunologia , Macrófagos/metabolismo , Mitocôndrias/metabolismo , Fagocitose/imunologia , Adolescente , Adulto , Sinalização do Cálcio , Inativação Gênica , Humanos , Imunidade Inata , Masculino , Adulto Jovem
5.
Nat Cell Biol ; 21(11): 1357-1369, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31659275

RESUMO

αMß2 integrin (complement receptor 3) is a major receptor for phagocytosis in macrophages. In other contexts, integrins' activities and functions are mechanically linked to actin dynamics through focal adhesions. We asked whether mechanical coupling of αMß2 integrin to the actin cytoskeleton mediates phagocytosis. We found that particle internalization was driven by formation of Arp2/3 and formin-dependent actin protrusions that wrapped around the particle. Focal complex-like adhesions formed in the phagocytic cup that contained ß2 integrins, focal adhesion proteins and tyrosine kinases. Perturbation of talin and Syk demonstrated that a talin-dependent link between integrin and actin and Syk-mediated recruitment of vinculin enable force transmission to target particles and promote phagocytosis. Altering target mechanical properties demonstrated more efficient phagocytosis of stiffer targets. Thus, macrophages use tyrosine kinase signalling to build a mechanosensitive, talin- and vinculin-mediated, focal adhesion-like molecular clutch, which couples integrins to cytoskeletal forces to drive particle engulfment.


Assuntos
Macrófagos/imunologia , Mecanotransdução Celular , Fagocitose/imunologia , Quinase Syk/genética , Talina/genética , Vinculina/genética , Citoesqueleto de Actina/imunologia , Citoesqueleto de Actina/ultraestrutura , Complexo 2-3 de Proteínas Relacionadas à Actina/genética , Complexo 2-3 de Proteínas Relacionadas à Actina/imunologia , Actinas/genética , Actinas/imunologia , Animais , Matriz Extracelular/imunologia , Matriz Extracelular/metabolismo , Adesões Focais/imunologia , Adesões Focais/ultraestrutura , /imunologia , Regulação da Expressão Gênica , Humanos , Antígeno de Macrófago 1/genética , Antígeno de Macrófago 1/imunologia , Macrófagos/citologia , Camundongos , Camundongos Endogâmicos C57BL , Microesferas , Fagossomos/imunologia , Fagossomos/ultraestrutura , Poliestirenos , Cultura Primária de Células , Células RAW 264.7 , Quinase Syk/imunologia , Células THP-1 , Talina/imunologia , Vinculina/imunologia
6.
Infect Immun ; 87(12)2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31548327

RESUMO

Upon microbial infection, host immune cells recognize bacterial cell envelope components through cognate receptors. Although bacterial cell envelope components function as innate immune molecules, the role of the physical state of the bacterial cell envelope (i.e., particulate versus soluble) in host immune activation has not been clearly defined. Here, using two different forms of the staphylococcal cell envelope of Staphylococcus aureus RN4220 and USA300 LAC strains, we provide biochemical and immunological evidence that the particulate state is required for the effective activation of host innate immune responses. In a murine model of peritoneal infection, the particulate form of the staphylococcal cell envelope (PCE) induced the production of chemokine (C-X-C motif) ligand 1 (CXCL1) and CC chemokine ligand 2 (CCL2), the chemotactic cytokines for neutrophils and monocytes, respectively, resulting in a strong influx of the phagocytes into the peritoneal cavity. In contrast, compared with PCE, the soluble form of cell envelope (SCE), which was derived from PCE by treatment with cell wall-hydrolyzing enzymes, showed minimal activity. PCE also induced the secretion of calprotectin (myeloid-related protein 8/14 [MRP8/14] complex), a phagocyte-derived antimicrobial protein, into the peritoneal cavity at a much higher level than did SCE. The injected PCE particles were phagocytosed by the infiltrated neutrophils and monocytes and then delivered to mediastinal draining lymph nodes. More importantly, intraperitoneally (i.p.) injected PCE efficiently protected mice from S. aureus infection, which was abolished by the depletion of either monocytes/macrophages or neutrophils. This study demonstrated that the physical state of bacterial cells is a critical factor for efficient host immune activation and the protection of hosts from staphylococcal infections.


Assuntos
Parede Celular/imunologia , Monócitos/imunologia , Neutrófilos/imunologia , Infecções Estafilocócicas/imunologia , Staphylococcus aureus/imunologia , Animais , Quimiocina CCL2/metabolismo , Quimiocina CXCL1/metabolismo , Feminino , Imunidade Inata/imunologia , Complexo Antígeno L1 Leucocitário/metabolismo , Macrófagos/imunologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fagocitose/imunologia , Infecções Estafilocócicas/microbiologia
7.
PLoS Negl Trop Dis ; 13(9): e0007674, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31536488

RESUMO

Here, we have investigated the possible effect of B-1 cells on the activity of peritoneal macrophages in E. cuniculi infection. In the presence of B-1 cells, peritoneal macrophages had an M1 profile with showed increased phagocytic capacity and index, associated with the intense microbicidal activity and a higher percentage of apoptotic death. The absence of B-1 cells was associated with a predominance of the M2 macrophages, reduced phagocytic capacity and index and microbicidal activity, increased pro-inflammatory and anti-inflammatory cytokines production, and higher percentual of necrosis death. In addition, in the M2 macrophages, spore of phagocytic E. cuniculi with polar tubular extrusion was observed, which is an important mechanism of evasion of the immune response. The results showed the importance of B-1 cells in the modulation of macrophage function against E. cuniculi infection, increasing microbicidal activity, and reducing the fungal mechanisms involved in the evasion of the immune response.


Assuntos
Subpopulações de Linfócitos B , Encephalitozoon cuniculi/imunologia , Encefalitozoonose/imunologia , Encefalitozoonose/patologia , Macrófagos Peritoneais/imunologia , Animais , Apoptose , Células Cultivadas , Feminino , Macrófagos Peritoneais/microbiologia , Camundongos Endogâmicos BALB C , Fagocitose/imunologia , Esporos Fúngicos/crescimento & desenvolvimento , Esporos Fúngicos/imunologia , Doenças por Imunodeficiência Combinada Ligada ao Cromossomo X/genética
8.
Infect Immun ; 87(12)2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31527124

RESUMO

Pseudomonas aeruginosa is an opportunistic pathogenic bacterium whose type III secretion system (T3SS) plays a critical role in acute infections. Translocation of the T3SS effectors into host cells induces cytotoxicity. In addition, the T3SS promotes the intracellular growth of P. aeruginosa during host infections. The T3SS regulon genes are regulated by an AraC-type regulator, ExsA. In this study, we found that an extracellular metalloprotease encoded by impA (PA0572) is under the regulation of ExsA. An ExsA consensus binding sequence was identified upstream of the impA gene, and direct binding of the site by ExsA was demonstrated via an electrophoretic mobility shift assay. We further demonstrate that secreted ImpA cleaves the macrophage surface protein CD44, which inhibits the phagocytosis of the bacterial cells by macrophages. Combined, our results reveal a novel ExsA-regulated virulence factor that cooperatively inhibits the functions of macrophages with the T3SS.


Assuntos
Proteínas de Bactérias/metabolismo , Macrófagos/imunologia , Metaloproteases/metabolismo , Fagocitose/imunologia , Pseudomonas aeruginosa/imunologia , Serina Endopeptidases/metabolismo , Transativadores/metabolismo , Animais , Proteínas de Bactérias/genética , Linhagem Celular Tumoral , Ensaio de Desvio de Mobilidade Eletroforética , Feminino , Regulação Bacteriana da Expressão Gênica/genética , Células HeLa , Humanos , Receptores de Hialuronatos/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Ligação Proteica , Pseudomonas aeruginosa/genética , Transativadores/genética , Sistemas de Secreção Tipo III/genética , Sistemas de Secreção Tipo III/metabolismo
9.
Int J Mol Sci ; 20(18)2019 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-31491977

RESUMO

In this experiment, the effects of a sudden drop of salinity on the immune response mechanisms of the ark shell Anadara kagoshimensis were examined by simulating the sudden drop of salinity that occurs in seawater after a rainstorm. Additionally, the differentially expressed genes (DEGs) were identified using transcriptome sequencing. When the salinity dropped from 30‱ (S30) to 14‱ (S14), the phagocytic activity of blood lymphocytes, the O2- levels produced from respiratory burst, the content of reactive oxygen species, and the activities of lysozymes and acid phosphatases increased significantly, whereas the total count of blood lymphocytes did not increase. Total count of blood lymphocytes in 22‱ salinity (S22) was significantly higher than that in any other group. The raw data obtained from sequencing were processed with Trimmomatic (Version 0.36). The expression levels of unigenes were calculated using transcripts per million (TPM) based on the effects of sequencing depth, gene length, and sample on reads. Differential expression analysis was performed using DESeq (Version 1.12.4). Transcriptome sequencing revealed 269 (101 up-regulated, 168 down-regulated), 326 (246 up-regulated, 80 down-regulated), and 185 (132 up-regulated, 53 down-regulated) significant DEGs from comparison of the S14 vs. S22, S22 vs. S30, and S14 vs. S30 groups, respectively. Gene Ontology enrichment analysis of the DEGs in these salinity comparison groups revealed that the cellular amino acid metabolic process, the regulation of protein processing, the regulation of response to stress, and other terms were significantly enriched. Kyoto Encyclopedia of Genes and Genomes enrichment analysis showed that nucleotide-binding, oligomerization domain (NOD)-like receptor signaling pathway (ko04621), apoptosis-multiple species (ko04215), Toll and Imd signaling pathway (ko04624), NF-κB signaling pathway (ko04064), apoptosis (ko04210), and focal adhesion (ko04510) were significantly enriched in all salinity comparison groups. qRT-PCR verification of 12 DEGs in the above six pathways was conducted, and the results were consistent with the transcriptome sequencing results in terms of up-regulation and down-regulation, which illustrates that the transcriptome sequencing data are credible. These results were used to preliminarily explore the effects of a sudden drop of salinity on blood physiological and biochemical indexes and immunoregulatory mechanisms of A. kagoshimensis. They also provide a theoretical basis for the selection of bottom areas optimal for release and proliferation of A. kagoshimensis required to restore the declining populations of this species.


Assuntos
Arcidae/fisiologia , Imunidade , Salinidade , Animais , Biomarcadores , Biologia Computacional/métodos , Meio Ambiente , Perfilação da Expressão Gênica , Imunidade/genética , Contagem de Linfócitos , Linfócitos/imunologia , Linfócitos/metabolismo , Anotação de Sequência Molecular , Oxigênio/metabolismo , Fagocitose/genética , Fagocitose/imunologia , Espécies Reativas de Oxigênio , Explosão Respiratória , Transdução de Sinais , Transcriptoma
10.
Cell Host Microbe ; 26(4): 551-563.e6, 2019 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-31540829

RESUMO

During infection, Legionella pneumophila translocates over 300 effector proteins into the host cytosol, allowing the pathogen to establish an endoplasmic reticulum (ER)-like Legionella-containing vacuole (LCV) that supports bacterial replication. Here, we perform a genome-wide CRISPR-Cas9 screen and secondary targeted screens in U937 human monocyte/macrophage-like cells to systematically identify host factors that regulate killing by L. pneumophila. The screens reveal known host factors hijacked by L. pneumophila, as well as genes spanning diverse trafficking and signaling pathways previously not linked to L. pneumophila pathogenesis. We further characterize C1orf43 and KIAA1109 as regulators of phagocytosis and show that RAB10 and its chaperone RABIF are required for optimal L. pneumophila replication and ER recruitment to the LCV. Finally, we show that Rab10 protein is recruited to the LCV and ubiquitinated by the effectors SidC/SdcA. Collectively, our results provide a wealth of previously undescribed insights into L. pneumophila pathogenesis and mammalian cell function.


Assuntos
Legionella pneumophila/patogenicidade , Doença dos Legionários/patologia , Fagocitose/imunologia , Proteínas/genética , Vacúolos/microbiologia , Animais , Proteínas de Bactérias/metabolismo , Linhagem Celular , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas/genética , Retículo Endoplasmático/metabolismo , Fatores de Troca do Nucleotídeo Guanina/genética , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Células HEK293 , Células HeLa , Humanos , Legionella pneumophila/genética , Macrófagos/metabolismo , Macrófagos/microbiologia , Camundongos , Células RAW 264.7 , Células U937 , Fatores de Virulência/genética , Proteínas rab de Ligação ao GTP/genética , Proteínas rab de Ligação ao GTP/metabolismo
11.
Fish Shellfish Immunol ; 93: 567-574, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31394161

RESUMO

HMGB2, a member of the high mobility group box family, plays an important role in host immune responses. However, the mechanism of action of HMGB2 is not well understood. Herein, a homologue from yellow catfish (Pelteobagrus fulvidraco) was cloned and named PfHMGB2. The deduced amino acid sequence of PfHMGB2 possessed a typical tripartite structure (two DNA binding boxes and an acid tail) and shared 90% identity with the predicted HMGB2 from I. punctatus. The mRNA of PfHMGB2 was widely distributed in all 11 tested tissues in healthy fish bodies and was significantly induced in the liver and head kidney when yellow catfish were injected with inactivated Aeromonas hydrophila. Consistently, PfHMGB2 mRNA could also be induced in yellow catfish peripheral blood leucocytes (PBL) by lipopolysaccharide. The recombinant PfHMGB2 protein was purified from E. coli BL21 (DE3):pET-28a/PfHMGB2 and showed DNA-binding affinity. Moreover, rPfHMGB2 improved the phagocytosis and proliferation activity and upregulated the mRNA expression of the pro-inflammatory cytokine TNFα in yellow catfish PBL. These results indicated that PfHMGB2 could protect yellow catfish from pathogen infection by activating PBL.


Assuntos
Peixes-Gato/genética , Peixes-Gato/imunologia , Doenças dos Peixes/imunologia , Regulação da Expressão Gênica/imunologia , Proteína HMGB2/genética , Proteína HMGB2/imunologia , Imunidade Inata/genética , Aeromonas hydrophila/fisiologia , Sequência de Aminoácidos , Animais , Proteínas de Peixes/química , Proteínas de Peixes/genética , Proteínas de Peixes/imunologia , Perfilação da Expressão Gênica/veterinária , Infecções por Bactérias Gram-Negativas/imunologia , Infecções por Bactérias Gram-Negativas/veterinária , Proteína HMGB2/química , Leucócitos/imunologia , Fagocitose/imunologia , Filogenia , Alinhamento de Sequência/veterinária
12.
Int J Mol Sci ; 20(16)2019 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-31398943

RESUMO

The immune response is essential to protect organisms from infection and an altered self. An organism's overall metabolic status is now recognized as an important and long-overlooked mediator of immunity and has spurred new explorations of immune-related metabolic abnormalities. Peroxisomes are essential metabolic organelles with a central role in the synthesis and turnover of complex lipids and reactive species. Peroxisomes have recently been identified as pivotal regulators of immune functions and inflammation in the development and during infection, defining a new branch of immunometabolism. This review summarizes the current evidence that has helped to identify peroxisomes as central regulators of immunity and highlights the peroxisomal proteins and metabolites that have acquired relevance in human pathologies for their link to the development of inflammation, neuropathies, aging and cancer. This review then describes how peroxisomes govern immune signaling strategies such as phagocytosis and cytokine production and their relevance in fighting bacterial and viral infections. The mechanisms by which peroxisomes either control the activation of the immune response or trigger cellular metabolic changes that activate and resolve immune responses are also described.


Assuntos
Suscetibilidade a Doenças , Imunidade , Inflamação/etiologia , Inflamação/metabolismo , Peroxissomos/metabolismo , Envelhecimento/genética , Envelhecimento/imunologia , Envelhecimento/metabolismo , Animais , Biomarcadores , Metabolismo Energético , Interações Hospedeiro-Patógeno/imunologia , Humanos , Imunidade/genética , Imunomodulação , Fagocitose/genética , Fagocitose/imunologia , Transdução de Sinais
13.
Biol Cell ; 111(10): 262-270, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31400233

RESUMO

BACKGROUND INFORMATION: After macrophage recognises and phagocytoses the microorganism, their phagosome undergoes a maturation process, which creates a hostile environment for the bacterium. The lumen is acidified, and proteolysis occurs to kill and degrade pathogen for further antigen presentation. It is important to understand the association between the macrophage intracellular activities and the outcome of infection. Different methods have been developed to measure the phagosome dynamics of macrophages, but there are still limitations. RESULTS: We used Mycobacterium tuberculosis (Mtb) antigens, the causative agent of tuberculosis (TB), as a model of infectious disease. Adopting a fluorescent bead-based assay, we developed beads coated with trehalose 6,6'dimycolate (TDM) from Mtb cell wall and ß-glucan from yeast cell wall to measure the macrophage phagosomal activities using a microplate reader. We examined the consistency of the assay using J774 cells and validated it using human monocyte-derived macrophages (hMDM) from healthy volunteers and TB patients. There was a decreased pH and increased proteolysis in the lumen of J774 cells after phagocytosing the ligand-coated beads. J774 macrophage showed no difference in the acidification and proteolysis in response to control IgG beads, TDM and ß-glucan beads. hMDM from healthy volunteers or TB patients showed heterogeneity in the intracellular activities when treated with ligand-coated beads. CONCLUSIONS AND SIGNIFICANCE: The beads coated with specific ligands from Mtb worked well in both macrophage cell line and human primary macrophages, which can be exploited to further study the phagosomal function of macrophage in TB. Our bead model can be applied to different ligands from other pathogens, which could extend the understanding of the associations between macrophage antimicrobial functions and outcomes of infectious diseases and the possible cellular mechanisms involved.


Assuntos
Antígenos de Bactérias/imunologia , Macrófagos/imunologia , Fagocitose/imunologia , Fagossomos/imunologia , Animais , Linhagem Celular , Humanos , Modelos Biológicos , Nanopartículas/química , beta-Glucanas/química
14.
Immunobiology ; 224(5): 605-613, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31402149

RESUMO

PURPOSE: The delayed rejection caused by strong cell-mediated innate and adaptive xenogeneic immune responses continues to be a major obstacle. Therefore, suppressing macrophage function could be effective in avoiding this type of rejection. In this study, the suppression of T-cell immunoglobulin and ITIM domain (TIGIT) function against macrophage-mediated xenogeneic rejection was investigated. MATERIAL AND METHODS: Naïve porcine aortic endothelial cell (PAEC) and PAEC transfectant with TIGIT (PAEC/TIGIT) were co-cultured with M1 macrophages, and the degree of cytotoxicity was determined by a counting beads assay. The anti/pro-inflammatory gene expression was determined by RT-PCR and the phosphorylated SHP-1 in the macrophages after co-culturing with PAEC or PAEC/TIGIT was evaluated by western blotting. RESULTS: CD155 was expressed at essentially equal levels on both M1 and M2 macrophages, whereas TIGIT was highly expressed on M2 macrophages but not in M1 macrophages. TIGIT on PAEC significantly reduced the cytotoxicity of M1 macrophages but no significant suppression of phagocytosis was detected. TIGIT also caused a decrease in the expression of pro-inflammatory cytokines, namely TNFα, IL-1ß and IL-12 in M1 macrophages. Furthermore, PAEC/TIGIT caused a significant increase in phosphorylated SHP-1 in M1 macrophages compared to PAEC. CONCLUSION: The findings of this study indicate that TIGIT suppresses xenogeneic M1 macrophage-induced cytotoxicity, probably at least in part, via the phosphorylation of SHP-1. In addition, the reduced expression of some pro-inflammatory cytokines, namely TNFα, IL-1ß and IL-12, was observed in M1 macrophages that had been cultured with PAEC/TIGIT.


Assuntos
Aorta/metabolismo , Citotoxicidade Imunológica , Células Endoteliais/metabolismo , Macrófagos/imunologia , Macrófagos/metabolismo , Receptores Imunológicos/genética , Imunidade Adaptativa , Animais , Aorta/imunologia , Células Cultivadas , Citocinas/metabolismo , Citotoxicidade Imunológica/genética , Células Endoteliais/imunologia , Expressão Gênica , Rejeição de Enxerto/genética , Rejeição de Enxerto/imunologia , Xenoenxertos , Humanos , Imunidade Inata , Mediadores da Inflamação/metabolismo , Modelos Biológicos , Fagocitose/genética , Fagocitose/imunologia , Proteína Tirosina Fosfatase não Receptora Tipo 6/metabolismo , Receptores Imunológicos/metabolismo , Receptores Virais/genética , Receptores Virais/metabolismo , Transdução de Sinais , Suínos , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo
15.
Int J Mol Sci ; 20(14)2019 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-31295956

RESUMO

CpG-DNA activates the host immune system to resist bacterial infections. In this study, we examined the protective effect of CpG-DNA in mice against Escherichia coli (E. coli) K1 infection. Administration of CpG-DNA increased the survival of mice after E. coli K1 infection, which reduces the numbers of bacteria in the organs. Pre-injection of mice with CpG-DNA before E. coli K1 infection increased the levels of the complement C3 but not C3a and C3b. The survival of the mice after E. coli K1 infection was significantly decreased when the mice were pre-injected with the cobra venom factor (CVF) removing the complement compared to the non-CVF-treated mice group. It suggests that the complement has protective roles against E. coli K1 infection. In addition, the survival of complement-depleted mice was increased by CpG-DNA pre-administration before E. coli K1 infection. Therefore, we suggest that CpG-DNA enhances the anti-bacterial activity of the immune system by augmenting the levels of complement systems after E. coli K1 infection and triggering other factors as well. Further studies are required to investigate the functional roles of the CpG-DNA-induced complement regulation and other factors against urgent bacterial infection.


Assuntos
Antibacterianos/farmacologia , Proteínas do Sistema Complemento/efeitos dos fármacos , Proteínas do Sistema Complemento/imunologia , Fatores Imunológicos/farmacologia , Oligodesoxirribonucleotídeos/farmacologia , Animais , Antibacterianos/administração & dosagem , Antibacterianos/química , Ativação do Complemento/efeitos dos fármacos , Ativação do Complemento/imunologia , Escherichia coli/efeitos dos fármacos , Escherichia coli/imunologia , Infecções por Escherichia coli/tratamento farmacológico , Infecções por Escherichia coli/imunologia , Infecções por Escherichia coli/microbiologia , Fatores Imunológicos/administração & dosagem , Fatores Imunológicos/química , Infusões Parenterais , Camundongos , Oligodesoxirribonucleotídeos/administração & dosagem , Oligodesoxirribonucleotídeos/química , Fagocitose/efeitos dos fármacos , Fagocitose/imunologia
16.
J Immunol Res ; 2019: 1629258, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31275997

RESUMO

The interferon- (IFN-) γ expression is elicited in response to microbial infections and activates immune surveillance by antimicrobial immune elements to induce microbial killing. Patients with adult-onset immunodeficiency who suffer from recurrent infections with microbes, particularly nontuberculous mycobacteria (NTM), commonly display genetic defects in IFN-γ signaling as well as the generation of anti-IFN-γ autoantibodies (autoAbs). Because IFN-γ is an activator of macrophage differentiation and a proinflammatory activator of innate immunity, the blockade effects of the autoAbs present in NTM patient serum on IFN-γ are hypothesized to regulate the antimicrobial function of macrophages. In the presence of patient serum, IFN-γ-induced type 1 macrophage (M1) differentiation was inhibited in PMA-stimulated human monocytic THP-1 cells. Treatment with patient serum significantly blocked the production of proinflammatory factors, including cytokines/chemokines and reactive oxygen/nitrogen species, by M1 macrophages. Importantly, IFN-γ-facilitated phagocytosis and degradation of heat-killed mycobacterium were decreased by cotreatment with patient serum. These results show the blockade activity of anti-IFN-γ autoAbs on IFN-γ-mediated antimicrobial immunity in macrophages.


Assuntos
Anticorpos Bloqueadores/imunologia , Autoanticorpos/imunologia , Interações Hospedeiro-Patógeno/imunologia , Imunomodulação , Interferon gama/imunologia , Anticorpos Bloqueadores/metabolismo , Anticorpos Bloqueadores/farmacologia , Autoanticorpos/farmacologia , Biomarcadores , Estudos de Casos e Controles , Citocinas/metabolismo , Interações Hospedeiro-Patógeno/efeitos dos fármacos , Humanos , Imunidade Inata , Interferon gama/antagonistas & inibidores , Ativação de Macrófagos , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Macrófagos/metabolismo , Monócitos/efeitos dos fármacos , Monócitos/imunologia , Monócitos/metabolismo , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Fagocitose/imunologia , Espécies Reativas de Oxigênio/metabolismo , Células THP-1
17.
Fish Shellfish Immunol ; 93: 191-199, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31326589

RESUMO

Interleukin-6 (IL-6) is one of the most pleiotropic cytokines because of its wide range of effects on cells of the immune and non-immune systems in the body. However, the role of IL-6 in fish monocytes/macrophages (MO/MФ) is poorly understood. In this study, we cloned the cDNA sequence of the IL-6 gene from ayu (Plecoglossus altivelis) and demonstrated using a tissue distribution assay that ayu interleukin-6 (PaIL-6) mRNA is expressed in all tested tissues. Changes in expression were observed in immune tissues as well as in MO/MФ after a Vibrio anguillarum infection; subsequently, PaIL-6 was expressed and purified to prepare anti-PaIL-6 antibodies. Recombinant PaIL-6 protein (rPaIL-6) treatment enhanced pro-inflammatory cytokine expression. Ayu interleukin-6 receptor ß (PaIL-6Rß) knockdown resulted in decreased pro-inflammatory cytokine expression in MO/MФ treated with rPaIL-6, whereas no significant changes were observed after ayu interleukin-6 receptor α (PaIL-6Rα) knockdown in MO/MФ. PaIL-6 and PaIL-6Rß knockdown in MO/MФ inhibited the phosphorylation of signal transducer and activator of transcription 1. Moreover, PaIL-6Rß knockdown inhibited the phagocytic and bactericidal ability of ayu MO/MФ treated with rPaIL-6. These data indicate that PaIL-6 may be able to regulate the function of ayu MO/MФ.


Assuntos
Receptor gp130 de Citocina/genética , Doenças dos Peixes/imunologia , Regulação da Expressão Gênica/imunologia , Imunidade Inata/genética , Interleucina-6/genética , Osmeriformes/genética , Osmeriformes/imunologia , Sequência de Aminoácidos , Animais , Receptor gp130 de Citocina/imunologia , Proteínas de Peixes/química , Proteínas de Peixes/genética , Proteínas de Peixes/imunologia , Perfilação da Expressão Gênica/veterinária , Técnicas de Silenciamento de Genes/veterinária , Interleucina-6/química , Interleucina-6/imunologia , Macrófagos/imunologia , Monócitos/imunologia , Fagocitose/genética , Fagocitose/imunologia , Fosforilação , Filogenia , Fator de Transcrição STAT1/metabolismo , Alinhamento de Sequência/veterinária , Vibrio/fisiologia , Vibrioses/imunologia , Vibrioses/veterinária
18.
Fish Shellfish Immunol ; 93: 559-566, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31330256

RESUMO

Shrimps like other arthropods rely on innate immune system, and may have some form of adaptive immunity in defending against pathogens. Phagocytosis is one of the oldest cellular processes, serving as a development process, a feeding mechanism and especially as a key defense reaction in innate immunity of all multicellular organisms. It is confirmed that crustacean hyperglycemic hormone (CHH) is one of the most important neuropeptides produced by Neuro-endocrine Immune (NEI) regulatory network, which undertakes important roles in various biological processes, especially in immune function and stress response. In this study, the recombinant Litopenaeus vannamei CHH (rLvCHH) was obtained from a bacterial expression system and the intracellular signaling pathways involved in the mechanism of phagocytosis after rLvCHH injection was investigated. The results showed that the contents of adenylyl cyclase (AC), phospholipase C (PLC) and calmodulin (CaM) in hemocytes were increased significantly after rLvCHH injection. Furthermore, the mRNA expression levels of NF-kB family members (relish and dorsal) and phagocytosis-related proteins in hemocytes were basically overexpressed after rLvCHH stimulation, while the expression level of NF-kB repressing factor (NKRF) gene was down-regulated significantly. Eventually, the total hemocyte count and phagocytic activity of hemocyte were dramatically enhanced within 3 h. Collectively, these results indicate that shrimps L. vannamei could carry out a simple but 'smart' NEI regulation through the action of neuroendocrine factors, which could couple with their receptors and trigger the downstream signaling pathways during the phagocytic responses of hemocytes.


Assuntos
Proteínas de Artrópodes/imunologia , Hemócitos/imunologia , Imunidade Inata/genética , Hormônios de Invertebrado/imunologia , Proteínas do Tecido Nervoso/imunologia , Penaeidae/genética , Penaeidae/imunologia , Fagocitose/imunologia , Animais , Proteínas de Artrópodes/genética , Relação Dose-Resposta a Droga , Hormônios de Invertebrado/genética , Proteínas do Tecido Nervoso/genética , Distribuição Aleatória , Transdução de Sinais/imunologia
19.
Redox Biol ; 26: 101279, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31349119

RESUMO

The phagocyte NADPH oxidase (the NOX2 complex) generates superoxide, the precursor to reactive oxygen species (ROS). ROS possess both antimicrobial and immunoregulatory function. Inactivating mutations in alleles of the NOX2 complex cause chronic granulomatous disease (CGD), characterized by an enhanced susceptibility to infections and autoimmune diseases such as Systemic lupus erythematosus (SLE). The latter is characterized by insufficient removal of dead cells, resulting in an autoimmune response against components of the cell's nucleus when non-cleared apoptotic cells lose their membrane integrity and present autoantigenic molecules in an inflammatory context. Here we aimed to shed light on the role of the NOX2 complex in handling of secondary necrotic cells (SNECs) and associated consequences for inflammation and autoimmunity during lupus. We show that individuals with SLE and CGD display accumulation of SNECs in blood monocytes and neutrophils. In a CGD phenotypic mouse strain (Ncf1** mice) build-up of SNECs in Ly6CHI blood monocytes was connected with a delayed degradation of the phagosomal cargo and accompanied by production of inflammatory mediators. Treatment with H2O2 or activators of ROS-formation reconstituted phagosomal abundance of SNECs to normal levels. Induction of experimental lupus further induced increased antibody-dependent uptake of SNECs into neutrophils. Lupus-primed Ncf1** neutrophils took up more SNECs than wild type neutrophils, whereas SNEC-accumulation in regulatory Ly6C-/LO monocytes was lower in Ncf1**mice. We deduce that the inflammatory rerouting of immune-stimulatory necrotic material into inflammatory phagocyte subsets contributes to the connection between low ROS production by the NOX2 complex and SLE.


Assuntos
NADPH Oxidase 2/metabolismo , Fagócitos/metabolismo , Animais , Autoanticorpos/imunologia , Citocinas/metabolismo , Concentração de Íons de Hidrogênio , Mediadores da Inflamação/metabolismo , Camundongos , Monócitos/imunologia , Monócitos/metabolismo , NADPH Oxidase 2/genética , Necrose/genética , Necrose/metabolismo , Neutrófilos/imunologia , Neutrófilos/metabolismo , Fagócitos/imunologia , Fagocitose/genética , Fagocitose/imunologia , Fagossomos/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Receptores de IgG/metabolismo
20.
Mol Immunol ; 114: 139-148, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31352230

RESUMO

AIM: To study the role of complement receptor 1 (CR1) for binding of Escherichia coli (E. coli) to erythrocytes, for leukocyte phagocytosis, oxidative burst and complement activation in human whole blood from a CR1 deficient (CR1D) patient and healthy controls with low, medium and high CR1 numbers. METHODS: Alexa-labelled bacteria were used to quantify erythrocyte-bound bacteria, free bacteria in plasma and phagocytosis using flow cytometry. Complement activation in plasma was measured by enzyme-linked immunosorbent assay. The CR1 numbers as well as C3bc and C4bc deposition on erythrocytes were measured by flow cytometry. Cytokines were measured using multiplex technology, and bacterial growth was measured by colony forming units. CR1 was blocked using the anti-CR1 blocking mAb 3D9. RESULTS: Approximately 85% of E. coli bound to erythrocytes after 15 min incubation in donor blood with high and medium CR1 numbers, 50% in the person with low CR1 numbers and virtually no detectable binding in the CR1D (r2 = 0.87, P < 0.0007). The number of free bacteria in plasma was inversely related to erythrocyte CR1 numbers (r2 = 0.98, P < 0.0001). E. coli-induced phagocytosis and oxidative burst were significantly enhanced by the anti-CR1 mAb 3D9 and in the CR1D and the donor with low CR1 numbers. E. coli-induced complement activation in plasma, C3bc and C4bc deposition on erythrocytes, and bacterial growth were similar in all four cases. CONCLUSIONS: CR1D and low CR1 numbers prevented E. coli binding to erythrocytes, increased free bacteria in plasma, phagocytosis and oxidative burst, but did not affect plasma or surface complement activation and bacterial growth.


Assuntos
Eritrócitos/imunologia , Escherichia coli/imunologia , Leucócitos/imunologia , Fagocitose/imunologia , Receptores de Complemento 3b/imunologia , Complexo Antígeno-Anticorpo/imunologia , Ativação do Complemento/imunologia , Eritrócitos/microbiologia , Humanos , Leucócitos/microbiologia , Explosão Respiratória/imunologia
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