Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 338
Filter
1.
Mucosal Immunol ; 10(3): 635-649, 2017 05.
Article in English | MEDLINE | ID: mdl-27579860

ABSTRACT

Celiac disease is caused by inflammatory T-cell responses against the insoluble dietary protein gliadin. We have shown that, in humanized mice, oral tolerance to deamidated chymotrypsin-digested gliadin (CT-TG2-gliadin) is driven by tolerogenic interferon (IFN)-γ- and interleukin (IL)-10-secreting type 1 regulatory T-like cells (Tr1-like cells) generated in the spleen but not in the mesenteric lymph nodes. We aimed to uncover the mechanisms underlying gliadin-specific Tr1-like-cell differentiation and hypothesized that proteolytic gliadin degradation by splenic macrophages is a decisive step in this process. In vivo depletion of macrophages caused reduced differentiation of splenic IFN-γ- and IL-10-producing Tr1-like cells after CT-TG2-gliadin but not gliadin peptide feed. Splenic macrophages, rather than dendritic cells, constitutively expressed increased mRNA levels of the endopeptidase Cathepsin D; macrophage depletion significantly reduced splenic Cathepsin D expression in vivo and Cathepsin D efficiently degraded recombinant γ-gliadin in vitro. In response to CT-TG2-gliadin uptake, macrophages enhanced the expression of Il27p28, a cytokine that favored differentiation of gliadin-specific Tr1-like cells in vitro, and was previously reported to increase Cathepsin D activity. Conversely, IL-27 neutralization in vivo inhibited splenic IFN-γ- and IL-10-secreting Tr1-like-cell differentiation after CT-TG2-gliadin feed. Our data infer that endopeptidase mediated gliadin degradation by macrophages and concomitant IL-27 production drive differentiation of splenic gliadin-specific Tr1-like cells.


Subject(s)
Celiac Disease/immunology , Gliadin/metabolism , Interleukin-27/metabolism , Macrophages/immunology , T-Lymphocytes, Regulatory/immunology , Animals , Antibodies, Neutralizing/metabolism , Cathepsin E/metabolism , Cell Differentiation , Cells, Cultured , Disease Models, Animal , Glutens/immunology , HLA-DQ Antigens/genetics , Humans , Immune Tolerance , Interferon-gamma/metabolism , Interleukin-10/metabolism , Mice , Mice, Inbred C57BL , Mice, Inbred DBA , Mice, SCID , Proteolysis , Receptors, Antigen, T-Cell/genetics , Th1 Cells/immunology
2.
J Clin Invest ; 125(12): 4429-46, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26571395

ABSTRACT

Thrombosis is a common, life-threatening consequence of systemic infection; however, the underlying mechanisms that drive the formation of infection-associated thrombi are poorly understood. Here, using a mouse model of systemic Salmonella Typhimurium infection, we determined that inflammation in tissues triggers thrombosis within vessels via ligation of C-type lectin-like receptor-2 (CLEC-2) on platelets by podoplanin exposed to the vasculature following breaching of the vessel wall. During infection, mice developed thrombi that persisted for weeks within the liver. Bacteria triggered but did not maintain this process, as thrombosis peaked at times when bacteremia was absent and bacteria in tissues were reduced by more than 90% from their peak levels. Thrombus development was triggered by an innate, TLR4-dependent inflammatory cascade that was independent of classical glycoprotein VI-mediated (GPVI-mediated) platelet activation. After infection, IFN-γ release enhanced the number of podoplanin-expressing monocytes and Kupffer cells in the hepatic parenchyma and perivascular sites and absence of TLR4, IFN-γ, or depletion of monocytic-lineage cells or CLEC-2 on platelets markedly inhibited the process. Together, our data indicate that infection-driven thrombosis follows local inflammation and upregulation of podoplanin and platelet activation. The identification of this pathway offers potential therapeutic opportunities to control the devastating consequences of infection-driven thrombosis without increasing the risk of bleeding.


Subject(s)
Blood Platelets/metabolism , Lectins, C-Type/metabolism , Salmonella Infections/metabolism , Salmonella typhimurium/metabolism , Thrombosis/metabolism , Animals , Blood Platelets/pathology , Interferon-gamma/genetics , Interferon-gamma/metabolism , Kupffer Cells/metabolism , Kupffer Cells/pathology , Lectins, C-Type/genetics , Mice , Mice, Inbred BALB C , Mice, Knockout , Platelet Membrane Glycoproteins/genetics , Platelet Membrane Glycoproteins/metabolism , Salmonella Infections/complications , Salmonella Infections/genetics , Salmonella Infections/pathology , Thrombosis/etiology , Thrombosis/genetics , Thrombosis/pathology , Toll-Like Receptor 4/genetics , Toll-Like Receptor 4/metabolism
3.
J Thromb Haemost ; 13(5): 821-6, 2015 May.
Article in English | MEDLINE | ID: mdl-25690668

ABSTRACT

BACKGROUND: Enhanced von Willebrand factor (VWF) clearance is important in the etiology of type 1 and type 2 von Willebrand disease (VWD). More than 20 different VWF point mutations have already been reported in patients with enhanced clearance. These include the VWD-Vicenza variant, which is characterized by an Arg1205His substitution in the VWF D3 domain. Critically, however, the molecular mechanisms through which single amino acid substitutions in VWF result in enhanced clearance of this complex multimeric glycoprotein have not been defined. OBJECTIVES: In this study, we have investigated the biological basis underlying the enhanced clearance of the VWF-R1205H variant. METHODS: Using VWF(-/-) mice, in vivo clearance rates were determined for a series of full-length and truncated recombinant VWF variants. In addition, the role of macrophages in modulating enhanced VWD-Vicenza clearance was investigated using clodronate liposome administration. RESULTS: Our findings demonstrate that substitutions of R1205 with histidine, cysteine or serine all result in markedly reduced survival of full-length recombinant VWF. Importantly, D'A3 fragments containing these same R1205 substitutions also demonstrated significantly enhanced clearance. In contrast to the reduced in vivo survival observed with R1205H, clearance of R1204H was not enhanced. Recent studies have demonstrated that hepatic and splenic macrophages play key roles in regulating VWF clearance. Importantly, macrophage-depletion also served to markedly attenuate the enhanced clearance phenotypes associated with VWF-R1205H, VWF-R1205S and VWF-R1205C. CONCLUSIONS: Collectively, these novel findings demonstrate a specific and critical role for the R1205 residue in modulating macrophage-mediated clearance of VWF in vivo.


Subject(s)
Arginine/chemistry , Macrophages/physiology , von Willebrand Factor/physiology , Animals , Mice , Mice, Knockout , von Willebrand Factor/chemistry
4.
Curr Mol Med ; 14(5): 690-702, 2014.
Article in English | MEDLINE | ID: mdl-24894172

ABSTRACT

Frequent outbreaks caused by influenza viruses pose considerable public health threats worldwide. Virus-inflicted alveolar damage represents a major contributor of acute lung injury in influenza. We have previously demonstrated that hepatocyte growth factor (HGF) produced by macrophages enhances alveolar epithelial proliferation during influenza infection. Here, we investigated the therapeutic efficacy of recombinant human HGF (rhHGF) and an antiviral agent (oseltamivir) alone or in combination to treat influenza viral pneumonia in macrophage-depleted BALB/c mice. Combination therapy of infected mice significantly reduced lung pathology and mortality compared to other animal groups that received either treatment alone. Combination treatment with rhHGF induced alveolar type II (AT2) epithelial hyperplasia more prominently in the distal airways, evident by increased cells with double-positive staining for surfactant protein-C and proliferating cell nuclear antigen within the alveolar epithelial lining. Similarly, rhHGF supplementation also induced stem cell antigen-1 (SCA-1) transcriptional expression at 5 days post-infection (dpi), but mRNA levels of both SCA-1 and its receptor c-KIT were decreased by 10 dpi. Microarray and pathway analyses indicated that rhHGF administration may act by accelerating tissue repair and suppressing inflammatory processes to minimize damage by infection and to restore lung function by earlier repair. These results reveal that transient administration of rhHGF may confer synergistic effects in enhancing pulmonary repair by promoting AT2 cell proliferation. Thus, the combination of rhHGF and oseltamivir may represent a promising therapeutic option against influenza pneumonia to improve existing antiviral treatment regimens.


Subject(s)
Antiviral Agents/therapeutic use , Hepatocyte Growth Factor/therapeutic use , Influenza, Human/drug therapy , Oseltamivir/therapeutic use , Pneumonia, Viral/drug therapy , Animals , Drug Therapy, Combination , Female , Humans , Mice , Mice, Inbred BALB C
5.
Oncogene ; 33(29): 3784-93, 2014 Jul 17.
Article in English | MEDLINE | ID: mdl-24013225

ABSTRACT

Increased expression of HBEGF in estrogen receptor-negative breast tumors is correlated with enhanced metastasis to distant organ sites and more rapid disease recurrence upon removal of the primary tumor. Our previous work has demonstrated a paracrine loop between breast cancer cells and macrophages in which the tumor cells are capable of stimulating macrophages through the secretion of colony-stimulating factor-1 while the tumor-associated macrophages (TAMs), in turn, aid in tumor cell invasion by secreting epidermal growth factor. To determine how the autocrine expression of epidermal growth factor receptor (EGFR) ligands by carcinoma cells would affect this paracrine loop mechanism, and in particular whether tumor cell invasion depends on spatial ligand gradients generated by TAMs, we generated cell lines with increased HBEGF expression. We found that autocrine HBEGF expression enhanced in vivo intravasation and metastasis and resulted in a novel phenomenon in which macrophages were no longer required for in vivo invasion of breast cancer cells. In vitro studies revealed that expression of HBEGF enhanced invadopodium formation, thus providing a mechanism for cell autonomous invasion. The increased invadopodium formation was directly dependent on EGFR signaling, as demonstrated by a rapid decrease in invadopodia upon inhibition of autocrine HBEGF/EGFR signaling as well as inhibition of signaling downstream of EGFR activation. HBEGF expression also resulted in enhanced invadopodium function via upregulation of matrix metalloprotease 2 (MMP2) and MMP9 expression levels. We conclude that high levels of HBEGF expression can short-circuit the tumor cell/macrophage paracrine invasion loop, resulting in enhanced tumor invasion that is independent of macrophage signaling.


Subject(s)
Autocrine Communication/genetics , Breast Neoplasms/genetics , Breast Neoplasms/pathology , Gene Expression Regulation, Neoplastic , Intercellular Signaling Peptides and Proteins/genetics , Animals , Breast Neoplasms/immunology , Breast Neoplasms/metabolism , Cell Line, Tumor , Cell Movement/genetics , ErbB Receptors/metabolism , Female , Heparin-binding EGF-like Growth Factor , Humans , Intercellular Signaling Peptides and Proteins/metabolism , Macrophages/immunology , Matrix Metalloproteinase 2/genetics , Matrix Metalloproteinase 2/metabolism , Matrix Metalloproteinase 9/genetics , Matrix Metalloproteinase 9/metabolism , Mice , Neoplasm Invasiveness , Neoplasm Metastasis , Tumor Burden
6.
Pancreatology ; 13(5): 508-16, 2013.
Article in English | MEDLINE | ID: mdl-24075516

ABSTRACT

INTRODUCTION: More effective therapies are required to improve survival of pancreatic cancer. Possible immunologic targets include tumour associated macrophages (TAMs), generally consisting of M1- and M2-macrophages. We have analysed the impact of TAMS on pancreatic cancer in a syngeneic orthotopic murine model. METHODS: 6606PDA murine pancreatic cancer cells were orthotopically injected into C57BL6 mice. Tumour growth was monitored using MRI. Macrophages were depleted by clodronate liposomes. Tumours including microvessel density were evaluated using immunohistochemistry, immunofluorescence and/or cytometric beads assays. Naïve macrophages were generated employing peritoneal macrophages. In vitro experiments included culturing of macrophages in tumour supernatants as well as tumour cells cultured in macrophage supernatants using arginase as well as Griess assays. RESULTS: Clodronate treatment depleted macrophages by 80% in livers (p = 0.0051) and by 60% in pancreatic tumours (p = 0.0169). MRI revealed tumour growth inhibition from 221.8 mm(3) to 92.3 mm(3) (p = 0.0216). Micro vessel densities were decreased by 44% (p = 0.0315). Yet, MCP-1-, IL-4- and IL-10-levels within pancreatic tumours were unchanged. 6606PDA culture supernatants led to a shift from naïve macrophages towards an M2-phenotype after a 36 h treatment (p < 0.0001), reducing M1-macrophages at the same time (p < 0.037). In vivo, M2-macrophages represented 85% of all TAMs (p < 0.0001). Finally, culture supernatants of M2-macrophages induced tumour growth in vitro by 63.2% (p = 0.0034). CONCLUSIONS: This quid pro quo of tumour cells and M2-macrophages could serve as a new target for future immunotherapies that interrupt tumour promoting activities of TAMs and change the iNOS-arginase balance towards their tumoricidal capacities.


Subject(s)
Macrophages/immunology , Pancreatic Neoplasms/immunology , Animals , Cell Differentiation , Cell Line, Tumor , Clodronic Acid/administration & dosage , Culture Media/pharmacology , Macrophages/drug effects , Macrophages/pathology , Male , Mice , Mice, Inbred C57BL , Neoplasm Transplantation , Pancreatic Neoplasms/pathology
7.
Int J Colorectal Dis ; 28(10): 1337-49, 2013 Oct.
Article in English | MEDLINE | ID: mdl-23657400

ABSTRACT

PURPOSE: Tumour-associated macrophages have been shown to promote proliferation, angiogenesis and metastasis in several carcinomas. The effect on colon cancer has not yet been clarified. Furthermore, Kupffer cells in the liver might initiate the formation of metastases by directly binding tumour cells. METHODS: An orthotopic syngeneic mouse model of colon cancer as well as a liver metastases model has been studied, using murine CT-26 colon cancer cells in Balb/c-mice. Macrophages were depleted in both models by clodronate liposomes. Tumour sizes and metastases were determined using 7-Tesla MRI. The macrophage and vascular density in the orthotopic tumours as well as the Kupffer cell density in the livers were evaluated using immunohistochemistry. RESULTS: Animals in the macrophage-depleted group displayed significantly smaller primary tumours (37 ± 20 mm(3)) compared to the control group (683 ± 389 mm(3), p = 0.0072). None of the mice in the depleted group showed liver or peritoneal metastases, whereas four of six control mice displayed liver and five out of six mice peritoneal metastases. The vascular density was significantly lower in the macrophage-depleted group (p = 0.0043). In the liver metastases model, animals of the Kupffer cell-depleted group (14.3 ± 7.7) showed significantly less liver metastases than mice of the two control groups (PBS liposomes, 118.5 ± 28.2, p = 0.0117; NaCl, 81.7 ± 23.2, p = 0.0266). The number of liver metastases correlated directly with the Kupffer cell density (p = 0.0221). CONCLUSION: Macrophages promote tumour growth, angiogenesis and metastases in this orthotopic syngeneic mouse model. Kupffer cells enhance the formation of metastases in the liver.


Subject(s)
Colonic Neoplasms/pathology , Liver Neoplasms/secondary , Macrophages/pathology , Neoplasm Transplantation , Animals , Cell Count , Cell Death , Cell Line, Tumor , Cell Proliferation , Colonic Neoplasms/blood supply , Disease Models, Animal , Kupffer Cells/pathology , Liver Neoplasms/pathology , Magnetic Resonance Imaging , Male , Mice , Mice, Inbred BALB C
8.
Mucosal Immunol ; 6(1): 45-55, 2013 Jan.
Article in English | MEDLINE | ID: mdl-22692455

ABSTRACT

Herpes simplex virus type 1 (HSV-1) is the leading cause of corneal blindness in the developed world due to reactivation of infectious virus and the subsequent immune response. The innate response that facilitates viral control in the cornea is currently unknown. In the present study using a mouse chimera model, we found that a bone marrow component is crucial in inhibiting viral replication and identified inflammatory monocytes (F4/80(+) Gr1(+)) as the responsible cell. CCL2 was critical for recruiting inflammatory monocytes, and a loss of this chemokine in CCL2(-/-) mice resulted in a loss of viral containment and inflammatory monocyte recruitment. To confirm these results, clodronate depletion of inflammatory monocytes resulted in elevated viral titers. Furthermore, siRNA targeting the innate sensor p204/IFI-16 resulted in a loss of CCL2 production. In conclusion, CCL2 expression driven by IFI-16 recognition of HSV-1 facilitates the recruitment of inflammatory monocytes into the cornea proper to control viral replication.


Subject(s)
Chemokine CCL2/biosynthesis , Inflammation/immunology , Inflammation/metabolism , Interferon-alpha/metabolism , Animals , Cornea/immunology , Cornea/metabolism , Cornea/virology , Female , Herpesvirus 1, Human/immunology , Inflammation/genetics , Leukemia Inhibitory Factor Receptor alpha Subunit/genetics , Leukemia Inhibitory Factor Receptor alpha Subunit/immunology , Leukemia Inhibitory Factor Receptor alpha Subunit/metabolism , Male , Mice , Mice, Knockout , Models, Immunological , Monocytes/immunology , Monocytes/metabolism , Nitric Oxide/biosynthesis , Virus Replication
9.
Hum Gene Ther ; 23(9): 960-79, 2012 Sep.
Article in English | MEDLINE | ID: mdl-22708837

ABSTRACT

Achieving high-efficiency tumor targeting after systemic delivery is a considerable challenge facing oncolytic gene therapists. Efficient retargeting should be combined with efforts to improve in vivo safety, reduce hepatotoxicity, minimize off-target interactions, and improve antitumoral potency and efficacy. We previously described the successful retargeting of adenovirus serotype 5 (Ad5) to α(v)ß(6), an integrin that is highly overexpressed in numerous human carcinomas. In this study, we have further modified this construct by introducing mutations that ablate coxsackievirus-adenovirus receptor (CAR) binding and putative interactions with factor IX (FIX)/C4b-binding protein (C4BP). We have found that the resulting vector, Ad5-477dlTAYT(A20), displays a desirable in vivo safety profile. This vector does not agglutinate human erythrocytes, fails to cause thrombocytopenia after intravenous delivery, has limited induction of proinflammatory cytokines, and results in low-level toxicity (aspartate aminotransferase/alanine aminotransferase) when compared with Ad5-EGFP(WT). Furthermore, it has reduced accumulation in Kupffer cells (1 hr) and limited hepatocyte transduction at later time points (24 and 96 hr). The parental vector, Ad5-EGFP(A20), also displayed many of these desirable properties. As a result of the improved safety profile of both A20-modified vectors, we escalated the dose from 2×10(10) to 4×10(10) viral particles in an antitumoral efficacy study. We observed improvements in reducing percent tumor growth at early time points (96 hr) when compared with Ad5-EGFP(WT), although increasing the dose did not affect the therapeutic outcome beneficially. On completion of the experiment, we detected increased E1A staining in the tumors of all A20-treated groups and we determined that E1A expression was localized largely within α(v)ß(6)(+) tumor cells. However, in spite of apparently efficient tumor transduction, this did not result in enhanced antitumoral efficacy as the virus failed to disseminate effectively throughout the tumor mass, presumably due to physical intratumoral restrictions. This highlights a remaining challenge that needs to be overcome before such vectors can be developed for future cancer gene therapy applications.


Subject(s)
Adenoviridae , Antigens, Neoplasm/metabolism , Coxsackie and Adenovirus Receptor-Like Membrane Protein/metabolism , Integrins/metabolism , Neoplasms/therapy , Oncolytic Virotherapy/methods , Oncolytic Viruses , Viral Tropism , Adenovirus E1A Proteins/biosynthesis , Animals , Antigens, Neoplasm/genetics , Binding Sites , CHO Cells , Coxsackie and Adenovirus Receptor-Like Membrane Protein/genetics , Cricetinae , Cricetulus , Female , Gene Expression Regulation, Viral/genetics , Hepatocytes/metabolism , Hepatocytes/virology , Humans , Integrins/genetics , Kupffer Cells/metabolism , Kupffer Cells/virology , Male , Mice , Mice, Inbred BALB C , Neoplasms/genetics , Neoplasms/metabolism , Neoplasms/virology , Transduction, Genetic
10.
Clin Exp Immunol ; 168(1): 153-63, 2012 Apr.
Article in English | MEDLINE | ID: mdl-22385250

ABSTRACT

Tolerance to lipopolysaccharide (LPS) constitutes a stress adaptation, in which a primary contact with LPS results in a minimal response when a second exposure with the same stimulus occurs. However, active important defence mechanisms are mounted during the tolerant state. Our aim was to assess the contribution of polymorphonuclear neutrophils (PMN) in the clearance of bacterial infection in a mouse model of tolerance to LPS. After tolerance was developed, we investigated in vivo different mechanisms of bacterial clearance. The elimination of a locally induced polymicrobial challenge was more efficient in tolerant mice both in the presence or absence of local macrophages. This was related to a higher number of PMN migrating to the infectious site as a result of an increased number of PMN from the marginal pool with higher chemotactic capacity, not because of differences in their phagocytic activity or reactive species production. In vivo, neutrophils extracellular trap (NET) destruction by nuclease treatment abolished the observed increased clearance in tolerant but not in control mice. In line with this finding, in vitro NETs formation was higher in PMN from tolerant animals. These results indicate that the higher chemotactic response from an increased PMN marginal pool and the NETs enhanced forming capacity are the main mechanisms mediating bacterial clearance in tolerant mice. To sum up, far from being a lack of response, tolerance to LPS causes PMN priming effects which favour distant and local anti-infectious responses.


Subject(s)
Bacterial Infections/immunology , Enterococcus/immunology , Immune Tolerance , Lipopolysaccharides/immunology , Neutrophils/immunology , Streptococcus/immunology , Animals , Bacterial Infections/microbiology , Chemotaxis, Leukocyte , Enterococcus/pathogenicity , Macrophages, Peritoneal/immunology , Macrophages, Peritoneal/microbiology , Male , Mice , Mice, Inbred BALB C , Neutrophils/physiology , Phagocytosis , Reactive Nitrogen Species/metabolism , Reactive Oxygen Species/metabolism , Streptococcus/pathogenicity
11.
Antiviral Res ; 92(2): 262-70, 2011 Nov.
Article in English | MEDLINE | ID: mdl-21878353

ABSTRACT

Foot and Mouth Disease (FMD) is an acute disease of cloven-hoofed species. We studied the protection and early immune response induced in the murine model by vaccines formulated with inactivated virus and two different adjuvants. The presence of IMS12802PR or ISA206VG adjuvants yielded protection against viral challenge at early times post vaccination and induced FMDV-specific, but non neutralizing, antibody titers. In vivo macrophage depletion in vaccinated mice severely decreased the protection levels after virus challenge, indicating a central role of this cell population in the response elicited by the vaccines. Accordingly, opsonophagocytosis of FITC-labelled virus was augmented in 802-FMDVi and 206-FMDVi vaccinated mice. These results demonstrate the ability of the studied adjuvants to enhance the protective responses of these inactivated vaccines without the increase in seroneutralizing antibodies and the main role of opsonization and phagocytosis in the early protective immune responses against FMD infection in the murine model.


Subject(s)
Foot-and-Mouth Disease/immunology , Foot-and-Mouth Disease/prevention & control , Macrophages/immunology , Viral Vaccines/administration & dosage , Viral Vaccines/immunology , Adjuvants, Immunologic/administration & dosage , Animals , Antibodies, Neutralizing/blood , Antibodies, Viral/blood , Leukocyte Reduction Procedures , Male , Mice , Mice, Inbred BALB C , Mice, Nude , Opsonin Proteins/immunology , Phagocytosis/immunology , Vaccines, Inactivated/administration & dosage , Vaccines, Inactivated/immunology
12.
Brain Behav Immun ; 25(4): 624-8, 2011 May.
Article in English | MEDLINE | ID: mdl-21324352

ABSTRACT

Glioma cells release soluble factors, which induce the expression of membrane type 1 matrix metalloprotease (MT1-MMP) in tumor associated microglia and then exploit MT1-MMP mediated matrix degradation for invasion. Here, we show that minocycline blocked the increase in MT1-MMP expression and activity in cultivated microglia stimulated with glioma conditioned medium. Glioma growth within an organotypic brain slice preparation was reduced by minocycline and this reduction depended on the presence of microglia. Glioma growth in an experimental mouse model was strongly reduced by the addition of minocycline to drinking water, compared to untreated controls. Coherently, we observed in our orthotopic glioma implantation model, that MT1-MMP was abundantly expressed in glioma associated microglia in controls, but was strongly attenuated in tumors of minocycline treated animals. Overall, our study indicates that the clinically approved antibiotic minocycline is a promising new candidate for adjuvant therapy against malignant gliomas.


Subject(s)
Antibiotics, Antineoplastic/pharmacology , Brain Neoplasms/drug therapy , Glioma/drug therapy , Matrix Metalloproteinase 14/metabolism , Microglia/drug effects , Minocycline/pharmacology , Animals , Brain Neoplasms/enzymology , Cells, Cultured , Chemotherapy, Adjuvant , Culture Media, Conditioned , Glioma/enzymology , Mice , Microglia/cytology , Microglia/enzymology , Neoplasm Invasiveness/prevention & control , Neoplasms, Experimental , Organ Culture Techniques
13.
Shock ; 35(2): 134-40, 2011 Feb.
Article in English | MEDLINE | ID: mdl-20577145

ABSTRACT

Hemorrhage and hemorrhagic shock instigate intestinal damage and inflammation. Multiple components of the innate immune response, including complement and neutrophil infiltration, are implicated in this pathology. To investigate the interaction of complement activation and other components of the innate immune response during hemorrhage, we treated mice after hemorrhage with CR2-fH, a targeted inhibitor of the alternative complement pathway and assessed intestinal damage and inflammation 2 h after hemorrhage. In wild-type mice, CR2-fH attenuated hemorrhage-induced, midjejunal damage and inflammation as determined by decreased mucosal damage, macrophage infiltration, leukotriene B4, IL-12p40, and TNF-[alpha] production. The critical nature of intestinal macrophage infiltration and activation in the response to hemorrhage was further determined using mice pretreated with clodronate-containing liposomes. The absence of either macrophages or IL-12p70 attenuated intestinal damage. These data suggest that complement activation and macrophage infiltration with IL-12p70 production are critical to hemorrhage-induced midjejunal damage and inflammation.


Subject(s)
Complement System Proteins/metabolism , Interleukin-12/biosynthesis , Intestinal Diseases/metabolism , Intestinal Mucosa/metabolism , Macrophages/metabolism , Shock, Hemorrhagic/metabolism , Animals , Bone Density Conservation Agents/pharmacology , Clodronic Acid/pharmacology , Complement Activation/drug effects , Complement Activation/genetics , Complement Activation/immunology , Complement Inactivating Agents/pharmacology , Complement System Proteins/genetics , Complement System Proteins/immunology , Immunity, Innate/drug effects , Immunity, Innate/genetics , Immunity, Innate/immunology , Interleukin-12/genetics , Interleukin-12/immunology , Intestinal Diseases/etiology , Intestinal Diseases/genetics , Intestinal Diseases/immunology , Intestines/immunology , Leukotriene B4/biosynthesis , Leukotriene B4/genetics , Leukotriene B4/immunology , Macrophage Activation/drug effects , Macrophage Activation/genetics , Macrophage Activation/immunology , Macrophages/immunology , Macrophages/pathology , Mice , Mice, Knockout , Neutrophil Infiltration/drug effects , Neutrophil Infiltration/genetics , Neutrophil Infiltration/immunology , Neutrophils/immunology , Neutrophils/metabolism , Shock, Hemorrhagic/complications , Shock, Hemorrhagic/drug therapy , Shock, Hemorrhagic/genetics , Shock, Hemorrhagic/immunology , Time Factors , Tumor Necrosis Factor-alpha/biosynthesis , Tumor Necrosis Factor-alpha/genetics , Tumor Necrosis Factor-alpha/immunology
14.
Brain Behav Immun ; 24(4): 564-8, 2010 May.
Article in English | MEDLINE | ID: mdl-20051263

ABSTRACT

Fatigue associated with recovery from muscle damage has recently been linked to increases in brain and muscle proinflammatory cytokines. However, little is known regarding the origin of these cytokines. Since macrophage-like cells in the brain are a primary source of cytokines, we used a brain specific macrophage depletion technique involving liposome encapsulated clodronate (CLD) to examine the role of macrophages on brain IL-1beta and fatigue following eccentric exercise-induced muscle damage. Mice were assigned to six groups: Downhill saline (DWNSAL), downhill clodronate (DWNCLD), uphill saline (UPSAL), uphill clodronate (UPCLD), non-running saline (CONSAL) or non-running clodronate (CONCLD). Mice were given intracerebroventricular (ICV) (10 microL) injections of clodronate-filled liposomes (CLD) to deplete macrophages, or saline-filled liposomes (SAL) and run on a treadmill at 22m/min and -14% (DWN) or 14% (UP) grade for 150 min. A subset of uphill and downhill running mice (n=40) was then run to fatigue on a treadmill at 36m/min, 8% grade at 24h after the uphill and downhill runs. A second subset of uphill, downhill, and control mice (n=30) was sacrificed 24h after the run for analysis of brain IL-1beta concentration. Histological examination confirmed previous reports that CLD administration reduced perivascular and meningeal macrophage subsets in the brain. CLD reduced IL-1beta concentration in the cortex of DWN mice (P<0.05), which was associated with enhanced treadmill performance 24h after both uphill and downhill runs (P<0.05) although the magnitude was greater following the downhill run. These results suggest that brain macrophages can contribute to the increase in brain IL-1beta and fatigue that are associated with recovery from exercise-induced muscle damage.


Subject(s)
Brain/metabolism , Interleukin-1beta/metabolism , Macrophages/metabolism , Muscle Fatigue , Muscle, Skeletal/injuries , Running , Animals , Bone Density Conservation Agents/administration & dosage , Bone Density Conservation Agents/pharmacology , Brain/cytology , Brain/drug effects , Cerebral Cortex/metabolism , Clodronic Acid/administration & dosage , Clodronic Acid/pharmacology , Enzyme-Linked Immunosorbent Assay , Injections, Intraventricular , Liposomes , Macrophages/drug effects , Male , Meninges/metabolism , Mice , Mice, Inbred C57BL , Muscle, Skeletal/physiopathology , Physical Conditioning, Animal/methods , Recovery of Function , Time Factors , Treatment Outcome
15.
Proc Natl Acad Sci U S A ; 106(30): 12530-5, 2009 Jul 28.
Article in English | MEDLINE | ID: mdl-19617536

ABSTRACT

Diffuse infiltration of glioma cells into normal brain tissue is considered to be a main reason for the unfavorable outcomes of patients with malignant gliomas. Invasion of glioma cells into the brain parenchyma is facilitated by metalloprotease-mediated degradation of the extracellular matrix. Metalloproteases are released as inactive pro-forms and get activated upon cleavage by membrane bound metalloproteases. Here, we show that membrane type 1 metalloprotease (MT1-MMP) is up-regulated in glioma-associated microglia, but not in the glioma cells. Overexpression of MT1-MMP is even lethal for glioma cells. Glioma-released factors trigger the expression and activity of MT1-MMP via microglial toll-like receptors and the p38 MAPK pathway, as deletion of the toll-like receptor adapter protein MyD88 or p38 inhibition prevented MT1-MMP expression and activity in cultured microglial cells. Microglial MT1-MMP in turn activates glioma-derived pro-MMP-2 and promotes glioma expansion, as shown in an ex vivo model using MT1-MMP-deficient brain tissue and a microglia depletion paradigm. Finally, MyD88 deficiency or microglia depletion largely attenuated glioma expansion in 2 independent in vivo models.


Subject(s)
Glioma/pathology , Matrix Metalloproteinase 14/metabolism , Microglia/pathology , Animals , Blotting, Western , Brain Neoplasms/genetics , Brain Neoplasms/metabolism , Brain Neoplasms/pathology , Cell Line, Tumor , Enzyme Precursors/metabolism , Female , Gelatinases/metabolism , Gene Expression Regulation, Neoplastic , Glioma/genetics , Glioma/metabolism , Green Fluorescent Proteins/genetics , Green Fluorescent Proteins/metabolism , Humans , Immunohistochemistry , Male , Matrix Metalloproteinase 14/genetics , Mice , Mice, Inbred C57BL , Mice, Knockout , Microglia/metabolism , Myeloid Differentiation Factor 88/genetics , Myeloid Differentiation Factor 88/metabolism , Reverse Transcriptase Polymerase Chain Reaction , Signal Transduction , Toll-Like Receptors/metabolism , Tumor Burden , p38 Mitogen-Activated Protein Kinases/metabolism
16.
Br J Cancer ; 100(1): 113-7, 2009 Jan 13.
Article in English | MEDLINE | ID: mdl-19066610

ABSTRACT

SGN-40 is a therapeutic antibody targeting CD40, which induces potent anti-lymphoma activities via direct apoptotic signalling cells and by cell-mediated cytotoxicity. Here we show antibody-dependent cellular phagocytosis (ADCP) by macrophages to contribute significantly to the therapeutic activities and that the antitumour effects of SGN-40 depend on Fc interactions.


Subject(s)
Antibodies, Monoclonal/pharmacology , Antineoplastic Agents/pharmacology , CD40 Antigens/immunology , Lymphoma/drug therapy , Macrophages/immunology , Receptors, Fc/physiology , Animals , Cell Line, Tumor , Humans , Mice , Mice, SCID , Phagocytosis
17.
Ann Rheum Dis ; 68(3): 420-6, 2009 Mar.
Article in English | MEDLINE | ID: mdl-18397959

ABSTRACT

OBJECTIVES: In the salivary glands of patients with primary Sjögren Syndrome (pSjS) an accumulation of dendritic cells (DCs) is seen, which is thought to play a role in stimulating local inflammation. Aberrancies in subsets of monocytes, generally considered the blood precursors for DCs, may play a role in this accumulation of DCs. This study is aimed at determining the level of mature CD14lowCD16+ monocytes in pSjS and their contribution to the accumulation of DCs in pSjS. METHODS: Levels of mature and immature monocytes in patients with pSjS (n = 19) and controls (n = 15) were analysed by flow cytometry. The reverse transmigration system was used for generation of DCs generated from monocyte subsets. The phenotype of DCs in pSjS salivary glands was analysed using immunohistochemistry. In vivo tracking of monocyte subsets was performed in a mouse model. RESULTS: Increased levels of mature CD14lowCD16+ monocytes were found in patients with pSjS (mean (SD) 14.5 (5.5)% vs 11.4 (3.4)%). These cells showed normal expression of chemokine receptor and adhesion molecules. Mature monocytes partly developed into DC-lysosome-associated membrane glycoprotein (LAMP)+ (19.6 (7.5)%) and CD83+ (16 (9)%) DCs, markers also expressed by DCs in pSjS salivary glands. Monocyte tracking in the non-obese diabetic (NOD) mouse showed that the homologue population of mature mouse monocytes migrated to the salivary glands, and preferentially developed into CD11c+ DCs in vivo. CONCLUSIONS: Mature monocytes are increased in pSjS and patient and mouse data support a model where this mature monocyte subset migrates to the salivary glands and develops into DCs.


Subject(s)
Dendritic Cells/immunology , Monocytes/immunology , Receptors, IgG/blood , Salivary Glands/immunology , Sjogren's Syndrome/immunology , Adult , Aged , Animals , Antigens, CD/blood , Cell Differentiation/immunology , Cells, Cultured , Cytokines/blood , GPI-Linked Proteins , Humans , Immunoglobulins/blood , Immunophenotyping , Lysosomal Membrane Proteins/blood , Membrane Glycoproteins/blood , Mice , Mice, Inbred NOD , Middle Aged , CD83 Antigen
18.
Br J Ophthalmol ; 92(11): 1528-33, 2008 Nov.
Article in English | MEDLINE | ID: mdl-18812385

ABSTRACT

AIM: To evaluate the role of macrophages in the development of posterior capsule opacification (PCO). METHODS: For this purpose, an extracapsular lens extraction was performed in 18 consecutive Sprague-Dawley rats. Animals were treated with liposomal clodronate (Cl(2)MDP-lip-treated group, n = 10) or phosphate-buffered saline (PBS) (control group, n = 8) 1 day preoperatively and on the first day postoperatively, and sacrificed 3 days postoperatively. Masked clinical, light microscopy and immunohistochemistry studies were conducted. The Fisher exact test and randomisation test were used to assess statistically differences between groups. RESULTS: A statistically significant reduction in the number of macrophages (ED1+, ED7+, ED8+) was found in the Cl(2)MDP-lip-treated group compared with the PBS-lip-treated group (p = 0.048, p = 0.004, p = 0.027, respectively). There were no statistically significant differences with regards to the presence/absence of central opacification (p = 0.29) and capsular wrinkling (p = 0.21) as detected clinically between groups. Similarly, a qualitative evaluation of the degree of PCO with regards to lens epithelial cell (LEC) proliferation, capsular wrinkling and Soemmerring ring formation showed no statistically significance between groups (p = 0.27, p = 0.061, p = 1.0, respectively). However, a statistically significant reduction in the number of lens epithelial cells (LEC) counted in the centre of the posterior capsule was found in the Cl(2)MDP-lip-treated group (p = 0.009). CONCLUSION: Depletion of macrophages was accompanied by a reduction in LEC in the centre of the posterior capsule in rodents.


Subject(s)
Cataract/pathology , Clodronic Acid/pharmacology , Epithelial Cells/pathology , Lens Capsule, Crystalline/pathology , Macrophages/pathology , Animals , Cataract/etiology , Disease Models, Animal , Epithelial Cells/drug effects , Lens Capsule, Crystalline/drug effects , Liposomes , Macrophages/drug effects , Male , Phacoemulsification , Rats , Rats, Sprague-Dawley , Sodium Chloride/pharmacology
19.
Am J Physiol Lung Cell Mol Physiol ; 295(2): L314-25, 2008 Aug.
Article in English | MEDLINE | ID: mdl-18556802

ABSTRACT

Activation of the Fas/Fas ligand (FasL) system in the lungs results in a form of injury characterized by alveolar epithelial apoptosis and neutrophilic inflammation. Studies in vitro show that Fas activation induces apoptosis in alveolar epithelial cells and cytokine production in alveolar macrophages. The main goal of this study was to determine the contribution of alveolar macrophages to Fas-induced lung inflammation in mice, by depleting alveolar macrophages using clodronate-containing liposomes. Liposomes containing clodronate or PBS were instilled by intratracheal instillation. After 24 h, the mice received intratracheal instillations of the Fas-activating monoclonal antibody Jo2 or an isotype control antibody and were studied 18 h later. The Jo2 MAb induced increases in bronchoalveolar lavage fluid (BALF) total neutrophils, lung caspase-3 activity, and BALF total protein and worsened histological lung injury in the macrophage-depleted mice. Studies in vitro showed that Fas activation induced the release of the cytokine KC in a mouse lung epithelial cell line, MLE-12. These results suggest that the lung inflammatory response to Fas activation is not primarily dependent on resident alveolar macrophages and may instead depend on cytokine release by alveolar epithelial cells.


Subject(s)
Apoptosis , Fas Ligand Protein/metabolism , Macrophages, Alveolar/metabolism , Respiratory Distress Syndrome/metabolism , Respiratory Mucosa/metabolism , fas Receptor/metabolism , Animals , Antibodies, Monoclonal/toxicity , Apoptosis/drug effects , Apoptosis/immunology , Bone Density Conservation Agents/pharmacology , Bronchoalveolar Lavage Fluid/immunology , Cell Line , Chemokine CXCL1/biosynthesis , Chemokine CXCL1/immunology , Clodronic Acid/pharmacology , Fas Ligand Protein/immunology , Inflammation/chemically induced , Inflammation/immunology , Inflammation/metabolism , Macrophages, Alveolar/immunology , Macrophages, Alveolar/pathology , Male , Mice , Respiratory Distress Syndrome/chemically induced , Respiratory Distress Syndrome/immunology , Respiratory Mucosa/immunology , Respiratory Mucosa/pathology , Time Factors , fas Receptor/immunology
20.
J Pathol ; 215(2): 108-17, 2008 Jun.
Article in English | MEDLINE | ID: mdl-18381617

ABSTRACT

Testicular inflammation with compromised fertility can occur despite the fact that the testis is considered an immunoprivileged organ. Testicular macrophages have been described as cells with an immunosuppressor profile, thus contributing to the immunoprivilege of the testis. Experimental autoimmune orchitis (EAO) is a model of organ-specific autoimmunity and testicular inflammation. EAO is characterized by an interstitial inflammatory mononuclear cell infiltration, damage of the seminiferous tubules and germ cell apoptosis. Here we studied the phenotype and functions of testicular macrophages during the development of EAO. By stereological analysis, we detected an increased number of resident (ED2+) and non-resident (ED1+) macrophages in the testicular interstitium of rats with orchitis. We showed that this increase was mainly due to monocyte recruitment. The in vivo administration of liposomes containing clodronate in rats undergoing EAO led to a reduction in the number of testicular macrophages, which correlated with a decreased incidence and severity of the testicular damage and suggests a pathogenic role of macrophages in EAO. By immunohistochemistry and flow cytometry we detected an increased number of testicular macrophages expressing MHC class II, CD80 and CD86 costimulatory molecules in rats with orchitis. Also, testicular macrophages from rats with EAO showed a higher production of IFNgamma (ELISA). We conclude that testicular macrophages participate in EAO development, and the ED1+ macrophage subset is the main pathogenic subpopulation. They stimulate the immune response through the production of pro-inflammatory cytokines and antigen presentation and thus activation of T cells in the target organ.


Subject(s)
Autoimmune Diseases/immunology , Macrophages/immunology , Orchitis/immunology , Testis/immunology , Animals , Apoptosis , Autoimmune Diseases/blood , Autoimmune Diseases/pathology , B7-1 Antigen/analysis , B7-2 Antigen/analysis , Cell Count , Clodronic Acid , Cytokines/blood , Flow Cytometry , Follicle Stimulating Hormone/blood , Immunoenzyme Techniques , Luteinizing Hormone/blood , Lymphocyte Activation , Male , Models, Animal , Orchitis/blood , Orchitis/pathology , Rats , Rats, Sprague-Dawley , Spermatozoa/pathology , T-Lymphocytes/immunology , Testosterone/blood
SELECTION OF CITATIONS
SEARCH DETAIL
...