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1

PDT-apoptotic tumor cells induce macrophage immune response  

NASA Astrophysics Data System (ADS)

Photodynamic therapy (PDT) functions as a cancer therapy through two major cell death mechanisms: apoptosis and necrosis. Immunological responses induced by PDT has been mainly associated with necrosis while apoptosis associated immune responses have not fully investigated. Heat shock proteins (HSPs) play an important role in regulating immune responses. In present study, we studied whether apoptotic tumor cells could induce immune response and how the HSP70 regulates immune response. The endocytosis of tumor cells by the activated macrophages was observed at single cell level by LSM. The TNF-? release of macrophages induced by co-incubated with PDT-apoptotic tumor cells was detected by ELISA. We found that apoptotic tumor cells treated by PDT could activate the macrophages, and the immune effect decreased evidently when HSP70 was blocked. These findings not only show that apoptosis can induce immunological responses, but also show HSP70 may serves as a danger signal for immune cells and induce immune responses to regulate the efficacy of PDT.

Zhou, Fei-fan; Xing, Da; Chen, Wei R.

2008-02-01

2

B cell maintenance subcapsular sinus macrophages protects against fatal viral infection independent adaptive immunity B cell maintenance subcapsular sinus macrophages protects against fatal viral infection independent adaptive immunity ASHLEY MOSEMAN Matteo Iannocare  

EPA Pesticide Factsheets

Search instead for B cell maintenance subcapsular sinus macrophages protects against fatal viral infection independent adaptive immunity B cell maintenance subcapsular sinus macrophages protects against fatal viral infection independent adaptive immunity ASHLEY MOSEMAN Matteo Iannocare ?

3

Analogous Functions of Macrophages and Langerhans Cells in the Initiation of the Immune Response  

Microsoft Academic Search

Langerhans cells constitute a minor cell population within the mammalian epidermis. This paper defines these cells immunologically and functionally and supports the concept that Langerhans cells are closely related to cells from the monocyte-macrophage-histiocyte series. Both cell types bear surface receptors for Fc-IgG and C3 and express surface glycoproteins, termed Ia antigens, encoded for by immune-response genes (Ir genes) of

Georg Stingl; Stephen I. Katz; Ethan M. Shevach; Alan S. Rosenthal; Ira Green

1978-01-01

4

Granulocyte macrophage colony-stimulating factor and the intestinal innate immune cell homeostasis in Crohn's disease.  

PubMed

Current literature consolidates the view of Crohn's disease (CD) as a form of immunodeficiency highlighting dysregulation of intestinal innate immunity in the pathogenesis of CD. Intestinal macrophages derived from blood monocytes play a key role in sustaining the innate immune homeostasis in the intestine, suggesting that the monocyte/macrophage compartment might be an attractive therapeutic target for the management of CD. Granulocyte macrophage colony-stimulating factor (GM-CSF) is a hematopoietic growth factor that also promotes myeloid cell activation, proliferation, and differentiation. GM-CSF has a protective effect in human CD and mouse models of colitis. However, the role of GM-CSF in immune and inflammatory reactions in the intestine is not well defined. Beneficial effects exerted by GM-CSF during intestinal inflammation could relate to modulation of the mucosal barrier function in the intestine, including epithelial cell proliferation, survival, restitution, and immunomodulatory actions. The aim of this review is to summarize potential mechanistic roles of GM-CSF in intestinal innate immune cell homeostasis and to highlight its central role in maintenance of the intestinal immune barrier in the context of immunodeficiency in CD. PMID:24503766

Däbritz, Jan

2014-03-01

5

Macrophage- and neutrophil-derived TNF-? instructs skin langerhans cells to prime antiviral immune responses.  

PubMed

Dendritic cells are major APCs that can efficiently prime immune responses. However, the roles of skin-resident Langerhans cells (LCs) in eliciting immune responses have not been fully understood. In this study, we demonstrate for the first time, to our knowledge, that LCs in cynomolgus macaque skin are capable of inducing antiviral-specific immune responses in vivo. Targeting HIV-Gag or influenza hemagglutinin Ags to skin LCs using recombinant fusion proteins of anti-Langerin Ab and Ags resulted in the induction of the viral Ag-specific responses. We further demonstrated that such Ag-specific immune responses elicited by skin LCs were greatly enhanced by TLR ligands, polyriboinosinic polyribocytidylic acid, and R848. These enhancements were not due to the direct actions of TLR ligands on LCs, but mainly dependent on TNF-? secreted from macrophages and neutrophils recruited to local tissues. Skin LC activation and migration out of the epidermis are associated with macrophage and neutrophil infiltration into the tissues. More importantly, blocking TNF-? abrogated the activation and migration of skin LCs. This study highlights that the cross-talk between innate immune cells in local tissues is an important component for the establishment of adaptive immunity. Understanding the importance of local immune networks will help us to design new and effective vaccines against microbial pathogens. PMID:25057007

Epaulard, Olivier; Adam, Lucille; Poux, Candice; Zurawski, Gerard; Salabert, Nina; Rosenbaum, Pierre; Dereuddre-Bosquet, Nathalie; Zurawski, Sandra; Flamar, Anne-Laure; Oh, Sangkon; Romain, Gabrielle; Chapon, Catherine; Banchereau, Jacques; Lévy, Yves; Le Grand, Roger; Martinon, Frédéric

2014-09-01

6

Intestinal antigen-presenting cells in mucosal immune homeostasis: crosstalk between dendritic cells, macrophages and B-cells.  

PubMed

The intestinal immune system maintains a delicate balance between immunogenicity against invading pathogens and tolerance of the commensal microbiota. Inflammatory bowel disease (IBD) involves a breakdown in tolerance towards the microbiota. Dendritic cells (DC), macrophages (M?) and B-cells are known as professional antigen-presenting cells (APC) due to their specialization in presenting processed antigen to T-cells, and in turn shaping types of T-cell responses generated. Intestinal DC are migratory cells, unique in their ability to generate primary T-cell responses in mesenteric lymph nodes or Peyer's patches, whilst M? and B-cells contribute to polarization and differentiation of secondary T-cell responses in the gut lamina propria. The antigen-sampling function of gut DC and M? enables them to sample bacterial antigens from the gut lumen to determine types of T-cell responses generated. The primary function of intestinal B-cells involves their secretion of large amounts of immunoglobulin A, which in turn contributes to epithelial barrier function and limits immune responses towards to microbiota. Here, we review the role of all three types of APC in intestinal immunity, both in the steady state and in inflammation, and how these cells interact with one another, as well as with the intestinal microenvironment, to shape mucosal immune responses. We describe mechanisms of maintaining intestinal immune tolerance in the steady state but also inappropriate responses of APC to components of the gut microbiota that contribute to pathology in IBD. PMID:25110405

Mann, Elizabeth R; Li, Xuhang

2014-08-01

7

Intestinal antigen-presenting cells in mucosal immune homeostasis: Crosstalk between dendritic cells, macrophages and B-cells  

PubMed Central

The intestinal immune system maintains a delicate balance between immunogenicity against invading pathogens and tolerance of the commensal microbiota. Inflammatory bowel disease (IBD) involves a breakdown in tolerance towards the microbiota. Dendritic cells (DC), macrophages (M?) and B-cells are known as professional antigen-presenting cells (APC) due to their specialization in presenting processed antigen to T-cells, and in turn shaping types of T-cell responses generated. Intestinal DC are migratory cells, unique in their ability to generate primary T-cell responses in mesenteric lymph nodes or Peyer’s patches, whilst M? and B-cells contribute to polarization and differentiation of secondary T-cell responses in the gut lamina propria. The antigen-sampling function of gut DC and M? enables them to sample bacterial antigens from the gut lumen to determine types of T-cell responses generated. The primary function of intestinal B-cells involves their secretion of large amounts of immunoglobulin A, which in turn contributes to epithelial barrier function and limits immune responses towards to microbiota. Here, we review the role of all three types of APC in intestinal immunity, both in the steady state and in inflammation, and how these cells interact with one another, as well as with the intestinal microenvironment, to shape mucosal immune responses. We describe mechanisms of maintaining intestinal immune tolerance in the steady state but also inappropriate responses of APC to components of the gut microbiota that contribute to pathology in IBD. PMID:25110405

Mann, Elizabeth R; Li, Xuhang

2014-01-01

8

Macrophages as IL-25/IL-33-Responsive Cells Play an Important Role in the Induction of Type 2 Immunity  

PubMed Central

Type 2 immunity is essential for host protection against nematode infection but is detrimental in allergic inflammation or asthma. There is a major research focus on the effector molecules and specific cell types involved in the initiation of type 2 immunity. Recent work has implicated an important role of epithelial-derived cytokines, IL-25 and IL-33, acting on innate immune cells that are believed to be the initial sources of type 2 cytokines IL-4/IL-5/IL-13. The identities of the cell types that mediate the effects of IL-25/IL-33, however, remain to be fully elucidated. In the present study, we demonstrate that macrophages as IL-25/IL-33-responsive cells play an important role in inducing type 2 immunity using both in vitro and in vivo approaches. Macrophages produced type 2 cytokines IL-5 and IL-13 in response to the stimulation of IL-25/IL-33 in vitro, or were the IL-13-producing cells in mice administrated with exogenous IL-33 or infected with Heligmosomoides bakeri. In addition, IL-33 induced alternative activation of macrophages primarily through autocrine IL-13 activating the IL-4R?-STAT6 pathway. Moreover, depletion of macrophages attenuated the IL-25/IL-33-induced type 2 immunity in mice, while adoptive transfer of IL-33-activated macrophages into mice with a chronic Heligmosomoides bakeri infection induced worm expulsion accompanied by a potent type 2 protective immune response. Thus, macrophages represent a unique population of the innate immune cells pivotal to type 2 immunity and a potential therapeutic target in controlling type 2 immunity-mediated inflammatory pathologies. PMID:23536877

Yang, Zhonghan; Grinchuk, Viktoriya; Urban, Joseph F.; Bohl, Jennifer; Sun, Rex; Notari, Luigi; Yan, Shu; Ramalingam, Thirumalai; Keegan, Achsah D.; Wynn, Thomas A.; Shea-Donohue, Terez; Zhao, Aiping

2013-01-01

9

Macrophages enhance the radiosensitizing activity of lipid A: A novel role for immune cells in tumor cell radioresponse  

SciTech Connect

Purpose: This study examines whether activated macrophages may radiosensitize tumor cells through the release of proinflammatory mediators. Methods and materials: RAW 264.7 macrophages were activated by lipid A, and the conditioned medium (CM) was analyzed for the secretion of cytokines and the production of nitric oxide (NO) through inducible nitric oxide synthase (iNOS). EMT-6 tumor cells were exposed to CM and analyzed for hypoxic cell radiosensitivity. The role of nuclear factor (NF)-{kappa}B in the transcriptional activation of iNOS was examined by luciferase reporter gene assay. Results: Clinical immunomodulator lipid A, at a plasma-relevant concentration of 3 {mu}g/mL, stimulated RAW 264.7 macrophages to release NO, tumor necrosis factor (TNF)-{alpha}, and other cytokines. This in turn activated iNOS-mediated NO production in EMT-6 tumor cells and drastically enhanced their radiosensitivity. Radiosensitization was abrogated by the iNOS inhibitor aminoguanidine but not by a neutralizing anti-TNF-{alpha} antibody. The mechanism of iNOS induction was linked to NF-{kappa}B but not to JAK/STAT signaling. Interferon-{gamma} further increased the NO production by macrophages to a level that caused radiosensitization of EMT-6 cells through the bystanding effect of diffused NO. Conclusions: We demonstrate for the first time that activated macrophages may radiosensitize tumor cells through the induction of NO synthesis, which occurs in both tumor and immune cells.

Ridder, Mark de [Academic Hospital, Free University Brussels (A.Z.-V.U.B.), Oncology Center, Cancer Research Unit, Brussels (Belgium)]. E-mail: Mark.De.Ridder@vub.ac.be; Verovski, Valeri N. [Academic Hospital, Free University Brussels (A.Z.-V.U.B.), Oncology Center, Cancer Research Unit, Brussels (Belgium); Darville, Martine I. [Laboratory of Experimental Medicine, Universite Libre de Bruxelles (ULB), Brussels (Belgium); Berge, Dirk L. van den [Academic Hospital, Free University Brussels (A.Z.-V.U.B.), Oncology Center, Cancer Research Unit, Brussels (Belgium); Monsaert, Christinne [Academic Hospital, Free University Brussels (A.Z.-V.U.B.), Oncology Center, Cancer Research Unit, Brussels (Belgium); Eizirik, Decio L. [Academic Hospital, Free University Brussels (A.Z.-V.U.B.), Oncology Center, Cancer Research Unit, Brussels (Belgium); Storme, Guy A. [Academic Hospital, Free University Brussels (A.Z.-V.U.B.), Oncology Center, Cancer Research Unit, Brussels (Belgium)

2004-10-01

10

MANGANESE CHLORIDE ENHANCES NATURAL CELL-MEDIATED IMMUNE EFFECTOR CELL FUNCTION: EFFECTS ON MACROPHAGES  

EPA Science Inventory

A single intramuscular injection of MnCl2 in mice caused an increase in macrophage functional activity. Spleen cell antibody-dependent cellmediated cytotoxicity (ADCC) against both chicken erythrocytes and P815 tumor cell targets was enhanced 24 hours following a single injection...

11

Innate immune discrimination of apoptotic cells: repression of proinflammatory macrophage transcription is coupled directly to specific recognition.  

PubMed

Physiological cell death is a process the purpose of which is the elimination of functionally inappropriate cells in a manner that does not elicit an inflammatory response. We have shown previously that the ability of apoptotic corpses to be recognized by macrophages and to modulate the proinflammatory responses of those cells represents paradoxically a gain-of-function acquired during the physiological cell death process. Cells that die pathologically (that is, necrotic vs apoptotic corpses) also are recognized by macrophages but do not down-regulate macrophage inflammatory responses; the recognition of these two classes of native dying cells occurs via distinct and noncompeting mechanisms. We have examined the apoptotic modulation of proinflammatory cytokine gene transcription in macrophages (by real-time RT-PCR analysis) and the corresponding modulation of transcriptional activators (by transcriptional reporter analyses). Our data demonstrate that apoptotic cells target the proinflammatory transcriptional machinery of macrophages with which they interact, without apparent effect on proximal steps of Toll-like receptor signaling. The modulatory activity of the corpse is manifest as an immediate-early inhibition of proinflammatory cytokine gene transcription, and is exerted directly upon binding to the macrophage, independent of subsequent engulfment and soluble factor involvement. Recognition and inflammatory modulation represent key elements of an innate immune response that discriminates live from effete cells, and without regard to self. PMID:14707059

Cvetanovic, Marija; Ucker, David S

2004-01-15

12

Distinct Innate Immune Responses in Human Macrophages and Endothelial Cells Infected with Shrew-borne Hantaviruses  

PubMed Central

Although hantaviruses have been previously considered as rodent-borne pathogens, recent studies demonstrate genetically distinct hantaviruses in evolutionarily distant non-rodent reservoirs, including shrews, moles and bats. The immunological responses to these newfound hantaviruses in humans are unknown. We compared the innate immune responses to Imjin virus (MJNV) and Thottapalayam virus (TPMV), two shrew-borne hantaviruses, with that toward two rodent-borne hantaviruses, pathogenic Hantann virus (HTNV) and nonpathogenic Prospect Hill virus (PHV). Infection of human macrophages and endothelial cells with either HTNV or MJNV triggered productive viral replication and up-regulation of anti-viral responsive gene expression from day 1 to day 3 postinfection, compared with PHV and TPMV. Furthermore, HTNV, MJNV and TPMV infection led to prolonged increased production of pro-inflammatory cytokines from days 3 to 7 postinfection. By contrast, PHV infection failed to induce pro-inflammatory responses. Distinct patterns of innate immune activation caused by MJNV suggest that it might be pathogenic to humans. PMID:22944108

Shin, Ok Sarah; Yanagihara, Richard; Song, Jin-Won

2013-01-01

13

Macrophages in homeostatic immune function.  

PubMed

Macrophages are not only involved in inflammatory and anti-infective processes, but also play an important role in maintaining tissue homeostasis. In this review, we summarize recent evidence investigating the role of macrophages in controlling angiogenesis, metabolism as well as salt and water balance. Particularly, we summarize the importance of macrophage tonicity enhancer binding protein (TonEBP, also termed nuclear factor of activated T-cells 5 [NFAT5]) expression in the regulation of salt and water homeostasis. Further understanding of homeostatic macrophage function may lead to new therapeutic approaches to treat ischemia, hypertension and metabolic disorders. PMID:24847274

Jantsch, Jonathan; Binger, Katrina J; Müller, Dominik N; Titze, Jens

2014-01-01

14

B cell maintenance of subcapsular sinus macrophages protects against a fatal viral infection independent of adaptive immunity.  

PubMed

Neutralizing antibodies have been thought to be required for protection against acutely cytopathic viruses, such as the neurotropic vesicular stomatitis virus (VSV). Utilizing mice that possess B cells but lack antibodies, we show here that survival upon subcutaneous (s.c.) VSV challenge was independent of neutralizing antibody production or cell-mediated adaptive immunity. However, B cells were absolutely required to provide lymphotoxin (LT) ?1?2, which maintained a protective subcapsular sinus (SCS) macrophage phenotype within virus draining lymph nodes (LNs). Macrophages within the SCS of B cell-deficient LNs, or of mice that lack LT?1?2 selectively in B cells, displayed an aberrant phenotype, failed to replicate VSV, and therefore did not produce type I interferons, which were required to prevent fatal VSV invasion of intranodal nerves. Thus, although B cells are essential for survival during VSV infection, their contribution involves the provision of innate differentiation and maintenance signals to macrophages, rather than adaptive immune mechanisms. PMID:22386268

Moseman, E Ashley; Iannacone, Matteo; Bosurgi, Lidia; Tonti, Elena; Chevrier, Nicolas; Tumanov, Alexei; Fu, Yang-Xin; Hacohen, Nir; von Andrian, Ulrich H

2012-03-23

15

B Cell Maintenance of Subcapsular Sinus Macrophages Protects against a Fatal Viral Infection Independent of Adaptive Immunity  

PubMed Central

SUMMARY Neutralizing antibodies have been thought to be required for protection against acutely cytopathic viruses, such as the neurotropic vesicular stomatitis virus (VSV). Utilizing mice that possess B cells but lack antibodies, we show here that survival upon subcutaneous (s.c.) VSV challenge was independent of neutralizing antibody production or cell-mediated adaptive immunity. However, B cells were absolutely required to provide lymphotoxin (LT) ?1?2, which maintained a protective subcapsular sinus (SCS) macrophage phenotype within virus draining lymph nodes (LNs). Macrophages within the SCS of B cell-deficient LNs, or of mice that lack LT?1?2 selectively in B cells, displayed an aberrant phenotype, failed to replicate VSV, and therefore did not produce type I interferons, which were required to prevent fatal VSV invasion of intranodal nerves. Thus, although B cells are essential for survival during VSV infection, their contribution involves the provision of innate differentiation and maintenance signals to macrophages, rather than adaptive immune mechanisms. PMID:22386268

Moseman, E. Ashley; Iannacone, Matteo; Bosurgi, Lidia; Tonti, Elena; Chevrier, Nicolas; Tumanov, Alexei; Fu, Yang-Xin; Hacohen, Nir; von Andrian, Ulrich H.

2012-01-01

16

Avian Macrophages: Regulators of Local and Systemic Immune Responses  

Microsoft Academic Search

Macrophages are key regulatory cells of the immune system involved in initiating and directing the innate and specific immune responses, the systemic acute phase response, tissue repair, and tissue remodel- ing. In the early stages of a challenge from invading microorganisms or from tissue injury, macrophages defend local and systemic homeostasis by initiating a complex series of cellular, biochemical, and

KIRK C. KLASING

1998-01-01

17

The role of indoleamine 2,3-dioxygenase (IDO) in immune tolerance: focus on macrophage polarization of THP-1 cells.  

PubMed

Macrophages can be divided into two groups as M1 and M2 phenotype. Our results and other groups revealed that IFN-? can up-regulate the IDO expression and differentiate THP-1 cells to M1 phenotype. Therefore we hypothesized that IDO may play potential roles in macrophage differentiation. Interesting, our results indicated that the ectopic IDO increases the expression of M2 markers such as IL-10 and CXCR4 while decreases the M1 markers such as CCR7 and IL-12p35. In contrast, the knockdown of IDO expression in THP-1 cells resulted in increased M1 markers and lower M2 markers. Our results suggested that the expression intensity of IDO modulates macrophages differentiation. These finding support the counter-regulatory role for IDO with regarding to the polarization of macrophages to restrain excessive or inappropriate immune activation in inflammatory or tumor microenvironment. It throws new light on the mechanisms about the immunosuppressive effect of IDO in tumor or inflammatory diseases. PMID:24721110

Wang, Xian-Feng; Wang, Hong-Sheng; Wang, Hao; Zhang, Fan; Wang, Ke-Fang; Guo, Qiang; Zhang, Ge; Cai, Shao-Hui; Du, Jun

2014-01-01

18

Vaccination with Irradiated Autologous Melanoma Cells Engineered to Secrete Human Granulocyte--Macrophage Colony-Stimulating Factor Generates Potent Antitumor Immunity in Patients with Metastatic Melanoma  

NASA Astrophysics Data System (ADS)

We conducted a Phase I clinical trial investigating the biologic activity of vaccination with irradiated autologous melanoma cells engineered to secrete human granulocyte--macrophage colony-stimulating factor in patients with metastatic melanoma. Immunization sites were intensely infiltrated with T lymphocytes, dendritic cells, macrophages, and eosinophils in all 21 evaluable patients. Although metastatic lesions resected before vaccination were minimally infiltrated with cells of the immune system in all patients, metastatic lesions resected after vaccination were densely infiltrated with T lymphocytes and plasma cells and showed extensive tumor destruction (at least 80%), fibrosis, and edema in 11 of 16 patients examined. Antimelanoma cytotoxic T cell and antibody responses were associated with tumor destruction. These results demonstrate that vaccination with irradiated autologous melanoma cells engineered to secrete granulocyte--macrophage colony-stimulating factor stimulates potent antitumor immunity in humans with metastatic melanoma.

Soiffer, Robert; Lynch, Thomas; Mihm, Martin; Jung, Ken; Rhuda, Catherine; Schmollinger, Jan C.; Hodi, F. Stephen; Liebster, Laura; Lam, Prudence; Mentzer, Steven; Singer, Samuel; Tanabe, Kenneth K.; Benedict Cosimi, A.; Duda, Rosemary; Sober, Arthur; Bhan, Atul; Daley, John; Neuberg, Donna; Parry, Gordon; Rokovich, Joseph; Richards, Laurie; Drayer, Jan; Berns, Anton; Clift, Shirley; Cohen, Lawrence K.; Mulligan, Richard C.; Dranoff, Glenn

1998-10-01

19

Macrophages are involved in hexachlorobenzene-induced adverse immune effects  

SciTech Connect

Hexachlorobenzene (HCB) is a persistent environmental pollutant that causes adverse immune effects in man and rat. The Brown Norway (BN) rat is very susceptible to HCB-induced immunopathology and oral exposure causes inflammatory skin and lung lesions, splenomegaly, lymph node (LN) enlargement, and increased serum levels of IgE and anti-ssDNA IgM. T cells play an important role but do not account for all adverse effects induced by HCB. Macrophages are probably also important and the relationship between macrophages and T cells was further investigated. To eliminate macrophages clodronate-liposomes were used. Furthermore, a kinetic study was performed to obtain insight in the early phase of the HCB-induced immune response. Also, experiments were performed to detect specific memory T cells. Therefore, an adoptive transfer study was performed. Our results indicate that macrophages are indeed involved in HCB-induced skin lesions, lung eosinophilia, and elevation of IgM against ssDNA. Kinetics showed that both skin and lung lesions appeared early after exposure. Moreover, immune effects could not be adaptively transferred. Thus, both macrophages and T cells are involved in HCB-induced immune effects but HCB exposure does not lead to specific T cell sensitization. Presumably, HCB exposure induces macrophage activation, thereby generating adjuvant signals that polyclonally stimulate T cells. Together, these events may lead to the observed immunopathology in BN rats.

Ezendam, Janine [National Institute for Public Health and the Environment, Laboratory for Toxicology, Pathology and Genetics, Bilthoven, PO Box 1 3720 BA (Netherlands)]. E-mail: Janine.Ezendam@rivm.nl; Kosterman, Kevin [Institute for Risk Assessment Sciences (IRAS), Immunotoxicology, Utrecht University, PO Box 80.176, 3508 TD Utrecht (Netherlands); Spijkerboer, Henneke [Institute for Risk Assessment Sciences (IRAS), Immunotoxicology, Utrecht University, PO Box 80.176, 3508 TD Utrecht (Netherlands); Bleumink, Rob [Institute for Risk Assessment Sciences (IRAS), Immunotoxicology, Utrecht University, PO Box 80.176, 3508 TD Utrecht (Netherlands); Hassing, Ine [Institute for Risk Assessment Sciences (IRAS), Immunotoxicology, Utrecht University, PO Box 80.176, 3508 TD Utrecht (Netherlands); Rooijen, Nico van [Faculty of Medicine, Department of Molecular Cell Biology, Free University, PO Box 7057, 1007 MB Amsterdam (Netherlands); Vos, Joseph G. [National Institute for Public Health and the Environment, Laboratory for Toxicology, Pathology and Genetics, Bilthoven, PO Box 1 3720 BA (Netherlands); Faculty of Veterinary Medicine, Department of Pathobiology, Utrecht University, PO Box 80.150, 3508 TD Utrecht (Netherlands); Pieters, Raymond [Institute for Risk Assessment Sciences (IRAS), Immunotoxicology, Utrecht University, PO Box 80.176, 3508 TD Utrecht (Netherlands)

2005-11-15

20

Macrophage migration inhibitory factor: a regulator of innate immunity  

Microsoft Academic Search

For more than a quarter of a century, macrophage migration inhibitory factor (MIF) has been a mysterious cytokine. In recent years, MIF has assumed an important role as a pivotal regulator of innate immunity. MIF is an integral component of the host antimicrobial alarm system and stress response that promotes the pro-inflammatory functions of immune cells. A rapidly increasing amount

Thierry Roger; Thierry Calandra

2003-01-01

21

Macrophage Cytokines: Involvement in Immunity and Infectious Diseases  

PubMed Central

The evolution of macrophages has made them primordial for both development and immunity. Their functions range from the shaping of body plans to the ingestion and elimination of apoptotic cells and pathogens. Cytokines are small soluble proteins that confer instructions and mediate communication among immune and non-immune cells. A portfolio of cytokines is central to the role of macrophages as sentries of the innate immune system that mediate the transition from innate to adaptive immunity. In concert with other mediators, cytokines bias the fate of macrophages into a spectrum of inflammation-promoting “classically activated,” to anti-inflammatory or “alternatively activated” macrophages. Deregulated cytokine secretion is implicated in several disease states ranging from chronic inflammation to allergy. Macrophages release cytokines via a series of beautifully orchestrated pathways that are spatiotemporally regulated. At the molecular level, these exocytic cytokine secretion pathways are coordinated by multi-protein complexes that guide cytokines from their point of synthesis to their ports of exit into the extracellular milieu. These trafficking proteins, many of which were discovered in yeast and commemorated in the 2013 Nobel Prize in Physiology or Medicine, coordinate the organelle fusion steps that are responsible for cytokine release. This review discusses the functions of cytokines secreted by macrophages, and summarizes what is known about their release mechanisms. This information will be used to delve into how selected pathogens subvert cytokine release for their own survival. PMID:25339958

Arango Duque, Guillermo; Descoteaux, Albert

2014-01-01

22

GPC3 expression in mouse ovarian cancer induces GPC3?specific T cell-mediated immune response through M1 macrophages and suppresses tumor growth.  

PubMed

Glypican-3 (GPC3) is specifically expressed in ovarian clear cell carcinoma (OCCC), hepatocellular carci-noma (HCC), and melanoma and lung cancer. GPC3 is being explored as a potential candidate for OCCC and HCC immunotherapy. As a tumor-associated antigen, induction of immune response of GPC3 in ovarian cancer remains elusive. We established a GPC3 transgenic mouse ovarian cancer cell line, OV2944-HM-1 (HM-1), and used the intraperitoneal ovarian cancer mouse model to investigate immune response in GPC3-expressing tumor. We found that GPC3 expression in the tumor increased F4/80+CD86+ macrophage (M1) proportion and caused GPC3-specific CD8+ T cell immune responses, and prolonged mouse survival. Our results demonstrated that GPC3 expression induced T cell-mediated immune response in this mouse ovarian cancer model and also provided supportive evidence that GPC3 is an ideal target for ovarian cancer immunotherapy. PMID:24992906

Luo, Chenhong; Shibata, Kiyosumi; Suzuki, Shiro; Kajiyama, Hiroaki; Senga, Takeshi; Koya, Yoshihiro; Daimon, Mina; Yamashita, Mamoru; Kikkawa, Fumitaka

2014-09-01

23

GPC3 expression in mouse ovarian cancer induces GPC3-specific T cell-mediated immune response through M1 macrophages and suppresses tumor growth  

PubMed Central

Glypican-3 (GPC3) is specifically expressed in ovarian clear cell carcinoma (OCCC), hepatocellular carcinoma (HCC), and melanoma and lung cancer. GPC3 is being explored as a potential candidate for OCCC and HCC immunotherapy. As a tumor-associated antigen, induction of immune response of GPC3 in ovarian cancer remains elusive. We established a GPC3 transgenic mouse ovarian cancer cell line, OV2944-HM-1 (HM-1), and used the intraperitoneal ovarian cancer mouse model to investigate immune response in GPC3-expressing tumor. We found that GPC3 expression in the tumor increased F4/80+CD86+ macrophage (M1) proportion and caused GPC3-specific CD8+ T cell immune responses, and prolonged mouse survival. Our results demonstrated that GPC3 expression induced T cell-mediated immune response in this mouse ovarian cancer model and also provided supportive evidence that GPC3 is an ideal target for ovarian cancer immunotherapy. PMID:24992906

LUO, CHENHONG; SHIBATA, KIYOSUMI; SUZUKI, SHIRO; KAJIYAMA, HIROAKI; SENGA, TAKESHI; KOYA, YOSHIHIRO; DAIMON, MINA; YAMASHITA, MAMORU; KIKKAWA, FUMITAKA

2014-01-01

24

Living T9 glioma cells expressing membrane macrophage colony-stimulating factor produce immediate tumor destruction by polymorphonuclear leukocytes and macrophages via a "paraptosis"-induced pathway that promotes systemic immunity against intracranial T9 gliomas.  

PubMed

Cloned T9-C2 glioma cells transfected with membrane macrophage colony-stimulating factor (mM-CSF) never formed subcutaneous tumors when implanted into Fischer rats, whereas control T9 cells did. The T9-C2 cells were completely killed within 1 day through a mechanism that resembled paraptosis. Vacuolization of the T9-C2 cell's mitochondria and endoplasmic reticulum started within 4 hours after implantation. By 24 hours, the dead tumor cells were swollen and terminal deoxynucleotide transferase-mediated dUTP nick-end labeling (TUNEL)-positive. Bcl2-transduced T9-C2 cells failed to form tumors in rats. Both T9 and T9-C2 cells produced cytokine-induced neutrophil chemoattractant that recruited the granulocytes into the tumor injection sites, where they interacted with the tumor cells. Freshly isolated macrophages killed the T9-C2 cells in vitro by a mechanism independent of phagocytosis. Nude athymic rats treated with antiasialo GM1 antibody formed T9-C2 tumors, whereas rats treated with a natural killer cell (NK)-specific antibody failed to form tumors. When treated with antipolymorphonuclear leukocyte (anti-PMN) and antimacrophage antibodies, 80% of nude rats formed tumors, whereas only 40% of the rats developed a tumor when a single antibody was used. This suggests that both PMNs and macrophages are involved in the killing of T9-C2 tumor cells. Immunocompetent rats that rejected the living T9-C2 cells were immune to the intracranial rechallenge with T9 cells. No vaccinating effect occurred if the T9-C2 cells were freeze-thawed, x-irradiated, or treated with mitomycin-C prior to injection. Optimal tumor immunization using mM-CSF-transduced T9 cells requires viable tumor cells. In this study optimal tumor immunization occurred when a strong inflammatory response at the injection of the tumor cells was induced. PMID:12149220

Chen, Yijun; Douglass, Thomas; Jeffes, Edward W B; Xu, Qingcheng; Williams, Christopher C; Arpajirakul, Neary; Delgado, Christina; Kleinman, Michael; Sanchez, Ramon; Dan, Qinghong; Kim, Ronald C; Wepsic, H Terry; Jadus, Martin R

2002-08-15

25

Alcoholism Causes Alveolar Macrophage Zinc Deficiency and Immune Dysfunction  

PubMed Central

Rationale: Alcohol use disorders cause oxidative stress in the lower airways and increase susceptibility to pneumonia and lung injury. Currently, no therapeutic options exist to mitigate the pulmonary consequences of alcoholism. Objectives: We recently determined in an animal model that alcohol ingestion impairs pulmonary zinc metabolism and causes alveolar macrophage immune dysfunction. The objective of this research is to determine the effects of alcoholism on zinc bioavailability and alveolar macrophage function in human subjects. Methods: We recruited otherwise healthy alcoholics (n = 17) and matched control subjects (n = 17) who underwent bronchoscopy for isolation of alveolar macrophages, which were analyzed for intracellular zinc, phagocytic function, and surface expression of granulocyte-macrophage colony–stimulating factor receptor; all three of these indices are decreased in experimental models. Measurements and Main Results: Alcoholic subjects had normal serum zinc, but significantly decreased alveolar macrophage intracellular zinc levels (adjusted means [SE], 718 [41] vs. 948 [25] RFU/cell; P < 0.0001); bacterial phagocytosis (adjusted means [SE], 1,027 [48] vs. 1,509 [76] RFU/cell; P < 0.0001); and expression of granulocyte-macrophage colony–stimulating factor receptor ? subunit (adjusted means [SE], 1,471 [42] vs. 2,114 [35] RFU/cell; P < 0.0001]. Treating alveolar macrophages with zinc acetate and glutathione in vitro increased intracellular zinc levels and improved their phagocytic function. Conclusions: These novel clinical findings provide evidence that alcohol abuse is associated with significant zinc deficiency and immune dysfunction within the alveolar space and suggest that dietary supplementation with zinc and glutathione precursors could enhance airway innate immunity and decrease the risk for pneumonia or lung injury in these vulnerable individuals. PMID:23805851

Yeligar, Samantha M.; Elon, Lisa; Brown, Lou Ann; Guidot, David M.

2013-01-01

26

Vaccination with Irradiated Tumor Cells Engineered to Secrete Murine Granulocyte-Macrophage Colony-Stimulating Factor Stimulates Potent, Specific, and Long-Lasting Anti-Tumor Immunity  

NASA Astrophysics Data System (ADS)

To compare the ability of different cytokines and other molecules to enhance the immunogenicity of tumor cells, we generated 10 retroviruses encoding potential immunomodulators and studied the vaccination properties of murine tumor cells transduced by the viruses. Using a B16 melanoma model, in which irradiated tumor cells alone do not stimulate significant anti-tumor immunity, we found that irradiated tumor cells expressing murine granulocyte-macrophage colony-stimulating factor (GM-CSF) stimulated potent, long-lasting, and specific anti-tumor immunity, requiring both CD4^+ and CD8^+ cells. Irradiated cells expressing interleukins 4 and 6 also stimulated detectable, but weaker, activity. In contrast to the B16 system, we found that in a number of other tumor models, the levels of anti-tumor immunity reported previously in cytokine gene transfer studies involving live, transduced cells could be achieved through the use of irradiated cells alone. Nevertheless, manipulation of the vaccine or challenge doses made it possible to demonstrate the activity of murine GM-CSF in those systems as well. Overall, our results have important implications for the clinical use of genetically modified tumor cells as therapeutic cancer vaccines.

Dranoff, Glenn; Jaffee, Elizabeth; Lazenby, Audrey; Golumbek, Paul; Levitsky, Hyam; Brose, Katja; Jackson, Valerie; Hamada, Hirofumi; Pardoll, Drew; Mulligan, Richard C.

1993-04-01

27

Innate immunity and monocyte-macrophage activation in atherosclerosis  

PubMed Central

Innate inflammation is a hallmark of both experimental and human atherosclerosis. The predominant innate immune cell in the atherosclerotic plaque is the monocyte-macrophage. The behaviour of this cell type within the plaque is heterogeneous and depends on the recruitment of diverse monocyte subsets. Furthermore, the plaque microenvironment offers polarisation and activation signals which impact on phenotype. Microenvironmental signals are sensed through pattern recognition receptors, including toll-like and NOD-like receptors - the latter of which are components of the inflammasome - thus dictating macrophage behaviour and outcome in atherosclerosis. Recently cholesterol crystals and modified lipoproteins have been recognised as able to directly engage these pattern recognition receptors. The convergent role of such pathways in terms of macrophage activation is discussed in this review. PMID:21526997

2011-01-01

28

Tumor-associated macrophages in clear cell renal cell carcinoma express both gastrin-releasing peptide and its receptor: a possible modulatory role of immune effectors cells  

PubMed Central

Purpose Renal cell carcinomas (RCC) frequently express the gastrin-releasing peptide receptor (GRP-R). Gastrin-releasing peptide (GRP) stimulates tumor cell proliferation and neoangiogenesis. Tumor-associated macrophages (TAM) comprise an important cellular component of these tumors. We analyzed the GRP/GRP-R network in clear cell RCC (ccRCC) and non-clear cell RCC (non-ccRCC) with special regard to its expression by macrophages, tumor cells and microvessels. Methods Gastrin-releasing peptide and GRP-R expression in 17 ccRCC and 9 non-ccRCC were analyzed by RT-PCR, immunohistochemistry and double immunofluorescence staining. Results Tumor-associated macrophages expressed GRP and GRP receptor in ccRCC. Tumor cells and microvessels showed low to intermediate GRP-R expression in nearly all cases. In 12 ccRCC tumor epithelia also expressed low levels of GRP. Microvascular GRP expression was found in nine cases of ccRCC. For non-RCC, the expression of GRP and GRP receptor expression pattern was similar. Conclusions Tumor-associated macrophages are the main source of GRP in RCC. GRP receptor on TAM, tumor epithelia and microvessels might be a molecular base of a GRP/GRP receptor network, potentially acting as a paracrine/autocrine modulator of TAM recruitment, tumor growth and neoangiogenesis. PMID:20012906

Bedke, Jens; Hemmerlein, Bernhard; Perske, Christina; Gross, Andreas

2009-01-01

29

Osteopetrotic ( op\\/ op) Mice Deficient in Macrophages Have the Ability to Mount a Normal T-Cell-Dependent Immune Response  

Microsoft Academic Search

The osteopetrotic (op\\/op) mouse possesses an inactivating mutation in the CSF-1 gene that is associated with a lack of certain mononuclear phagocyte populations. To examine the effects of these deficiencies on T-cell-dependent immune functions, the responses of op\\/ op and normal mice to a T-cell-dependent antigen, ovalbumin, and to a foreign histocompatibility antigen were compared. The ability of op\\/op mice

Ming-Der Y. Chang; E. Richard Stanley; Houman Khalili; Orin Chisholm; Jeffrey W. Pollard

1995-01-01

30

Maternal immune activation leads to activated inflammatory macrophages in offspring.  

PubMed

Several epidemiological studies have shown an association between infection or inflammation during pregnancy and increased risk of autism in the child. In addition, animal models have illustrated that maternal inflammation during gestation can cause autism-relevant behaviors in the offspring; so called maternal immune activation (MIA) models. More recently, permanent changes in T cell cytokine responses were reported in children with autism and in offspring of MIA mice; however, the cytokine responses of other immune cell populations have not been thoroughly investigated in these MIA models. Similar to changes in T cell function, we hypothesized that following MIA, offspring will have long-term changes in macrophage function. To test this theory, we utilized the poly (I:C) MIA mouse model in C57BL/6J mice and examined macrophage cytokine production in adult offspring. Pregnant dams were given either a single injection of 20mg/kg polyinosinic-polycytidylic acid, poly (I:C), or saline delivered intraperitoneally on gestational day 12.5. When offspring of poly (I:C) treated dams reached 10weeks of age, femurs were collected and bone marrow-derived macrophages were generated. Cytokine production was measured in bone marrow-derived macrophages incubated for 24h in either growth media alone, LPS, IL-4/LPS, or IFN-?/LPS. Following stimulation with LPS alone, or the combination of IFN-?/LPS, macrophages from offspring of poly (I:C) treated dams produced higher levels of IL-12(p40) (p<0.04) suggesting an increased M1 polarization. In addition, even without the presence of a polarizing cytokine or LPS stimulus, macrophages from offspring of poly (I:C) treated dams exhibited a higher production of CCL3 (p=0.05). Moreover, CCL3 levels were further increased when stimulated with LPS, or polarized with either IL-4/LPS or IFN-?/LPS (p<0.05) suggesting a general increase in production of this chemokine. Collectively, these data suggest that MIA can produce lasting changes in macrophage function that are sustained into adulthood. PMID:24566386

Onore, Charity E; Schwartzer, Jared J; Careaga, Milo; Berman, Robert F; Ashwood, Paul

2014-05-01

31

Crude extract of Polygonum cuspidatum stimulates immune responses in normal mice by increasing the percentage of Mac?3?positive cells and enhancing macrophage phagocytic activity and natural killer cell cytotoxicity.  

PubMed

Polygonum cuspidatum is a natural plant that is used in traditional Chinese herbal medicine. The crude extract of Polygonum cuspidatum (CEPC) has numerous biological effects; however, there is a lack of studies on the effects of CEPC on immune responses in normal mice. The aim of the present study was to determine the in vivo effects of CEPC on immune responses in normal mice. CEPC (0, 50, 100, 150 and 200 mg/kg) was orally administered to BALB/c mice for three weeks, following which blood, liver, and spleen samples were collected. CEPC did not significantly affect the total body weight, or tissue weights of the liver or spleen, as compared with the control mice. CEPC increased the percentages of CD3 (T?cell marker), 11b (monocytes) and Mac?3 (macrophages) positive?cells, and reduced the percentage of CD19?positive cells (B?cell marker), as compared with the control mice. CEPC (100 mg/kg) stimulated macrophage phagocytosis of blood samples but did not affect macrophage phagocytosis in the peritoneum. Activity of the splenic natural killer cells was increased in response to CEPC (50 mg/kg) treatment. Furthermore, CEPC inhibited T? and B?cell proliferation when the cells were stimulated with concanavalin A and lipopolysaccharide, respectively. PMID:25338846

Chueh, Fu-Shin; Lin, Jen-Jyh; Lin, Ju-Hwa; Weng, Shu-Wen; Huang, Yi-Ping; Chung, Jing-Gung

2015-01-01

32

Crude extract of Polygonum cuspidatum stimulates immune responses in normal mice by increasing the percentage of Mac-3-positive cells and enhancing macrophage phagocytic activity and natural killer cell cytotoxicity  

PubMed Central

Polygonum cuspidatum is a natural plant that is used in traditional Chinese herbal medicine. The crude extract of Polygonum cuspidatum (CEPC) has numerous biological effects; however, there is a lack of studies on the effects of CEPC on immune responses in normal mice. The aim of the present study was to determine the in vivo effects of CEPC on immune responses in normal mice. CEPC (0, 50, 100, 150 and 200 mg/kg) was orally administered to BALB/c mice for three weeks, following which blood, liver, and spleen samples were collected. CEPC did not significantly affect the total body weight, or tissue weights of the liver or spleen, as compared with the control mice. CEPC increased the percentages of CD3 (T-cell marker), 11b (monocytes) and Mac-3 (macrophages) positive-cells, and reduced the percentage of CD19-positive cells (B-cell marker), as compared with the control mice. CEPC (100 mg/kg) stimulated macrophage phagocytosis of blood samples but did not affect macrophage phagocytosis in the peritoneum. Activity of the splenic natural killer cells was increased in response to CEPC (50 mg/kg) treatment. Furthermore, CEPC inhibited T- and B-cell proliferation when the cells were stimulated with concanavalin A and lipopolysaccharide, respectively. PMID:25338846

CHUEH, FU-SHIN; LIN, JEN-JYH; LIN, JU-HWA; WENG, SHU-WEN; HUANG, YI-PING; CHUNG, JING-GUNG

2015-01-01

33

Macrophage Migration Inhibitory Factor is a Critical Mediator of the Activation of Immune Cells by Exotoxins of Gram-Positive Bacteria  

Microsoft Academic Search

Discovered in the early 1960s as a T cell cytokine, the protein mediator known as macrophage migration inhibitory factor (MIF) has been found recently to be a pituitary peptide released during the physiological stress response, a proinflammatory macrophage cytokine secreted after LPS stimulation, and a T cell product expressed as part of the antigen-dependent activation response. We report herein that

Thierry Calandra; Lori A. Spiegel; Christine N. Metz; Richard Bucala

1998-01-01

34

Cell–Cell Contacts with Epithelial Cells Modulate the Phenotype of Human Macrophages  

Microsoft Academic Search

Interactions of macrophages with epithelium represent one of the pathways involved in regulating local immune mechanisms. We studied the effect of cell–cell contact with an epithelial monolayer on the phenotype of macrophages. Human monocytes and THP-1 macrophages were co-cultured with monolayers of human bronchial epithelial cells (HBECs), the alveolar type II-like cell line A549, renal adenocarcinoma epithelial cells (RA), and

I. St?íž; A. Slav?ev; J. Kalanin; M. Jarešová; S. I. Rennard

2001-01-01

35

Epigenetic programming of monocyte-to-macrophage differentiation and trained innate immunity.  

PubMed

Monocyte differentiation into macrophages represents a cornerstone process for host defense. Concomitantly, immunological imprinting of either tolerance or trained immunity determines the functional fate of macrophages and susceptibility to secondary infections. We characterized the transcriptomes and epigenomes in four primary cell types: monocytes and in vitro-differentiated naïve, tolerized, and trained macrophages. Inflammatory and metabolic pathways were modulated in macrophages, including decreased inflammasome activation, and we identified pathways functionally implicated in trained immunity. ?-glucan training elicits an exclusive epigenetic signature, revealing a complex network of enhancers and promoters. Analysis of transcription factor motifs in deoxyribonuclease I hypersensitive sites at cell-type-specific epigenetic loci unveiled differentiation and treatment-specific repertoires. Altogether, we provide a resource to understand the epigenetic changes that underlie innate immunity in humans. PMID:25258085

Saeed, Sadia; Quintin, Jessica; Kerstens, Hindrik H D; Rao, Nagesha A; Aghajanirefah, Ali; Matarese, Filomena; Cheng, Shih-Chin; Ratter, Jacqueline; Berentsen, Kim; van der Ent, Martijn A; Sharifi, Nilofar; Janssen-Megens, Eva M; Ter Huurne, Menno; Mandoli, Amit; van Schaik, Tom; Ng, Aylwin; Burden, Frances; Downes, Kate; Frontini, Mattia; Kumar, Vinod; Giamarellos-Bourboulis, Evangelos J; Ouwehand, Willem H; van der Meer, Jos W M; Joosten, Leo A B; Wijmenga, Cisca; Martens, Joost H A; Xavier, Ramnik J; Logie, Colin; Netea, Mihai G; Stunnenberg, Hendrik G

2014-09-26

36

B Cell Maintenance of Subcapsular Sinus Macrophages Protects against a Fatal Viral Infection  

E-print Network

Immunity Article B Cell Maintenance of Subcapsular Sinus Macrophages Protects against a Fatal Viral Infection Independent of Adaptive Immunity E. Ashley Moseman,1,8 Matteo Iannacone,1,2,8,* Lidia Bosurgi,1 a protective subcapsular sinus (SCS) macrophage phenotype within virus draining lymph nodes (LNs). Macrophages

37

Regulation of the immune response by macrophage migration inhibitory factor: biological and structural features  

Microsoft Academic Search

The classical T cell cytokine macrophage migration inhibitory factor (MIF) has reemerged recently as a critical mediator\\u000a of the host immune and stress response. MIF has been found to be a mediator of several diseases including gram-negative septic\\u000a shock and delayed-type hypersensitivity reactions. Its immunological functions include the modulation of the host macrophage\\u000a and T and B cell response. In

Jürgen Bernhagen; Thierry Calandra; Richard Bucala

1998-01-01

38

A TNF-Regulated Recombinatorial Macrophage Immune Receptor Implicated in Granuloma Formation in Tuberculosis  

PubMed Central

Macrophages play a central role in host defense against mycobacterial infection and anti- TNF therapy is associated with granuloma disorganization and reactivation of tuberculosis in humans. Here, we provide evidence for the presence of a T cell receptor (TCR) ?? based recombinatorial immune receptor in subpopulations of human and mouse monocytes and macrophages. In vitro, we find that the macrophage-TCR?? induces the release of CCL2 and modulates phagocytosis. TNF blockade suppresses macrophage-TCR?? expression. Infection of macrophages from healthy individuals with mycobacteria triggers formation of clusters that express restricted TCR V? repertoires. In vivo, TCR?? bearing macrophages abundantly accumulate at the inner host-pathogen contact zone of caseous granulomas from patients with lung tuberculosis. In chimeric mouse models, deletion of the variable macrophage-TCR?? or TNF is associated with structurally compromised granulomas of pulmonary tuberculosis even in the presence of intact T cells. These results uncover a TNF-regulated recombinatorial immune receptor in monocytes/macrophages and demonstrate its implication in granuloma formation in tuberculosis. PMID:22114556

Streich, Roswita; Breysach, Caroline; Raddatz, Dirk; Oniga, Septimia; Peccerella, Teresa; Findeisen, Peter; Kzhyshkowska, Julia; Gratchev, Alexei; Schweyer, Stefan; Saunders, Bernadette; Wessels, Johannes T.; Mobius, Wiebke; Keane, Joseph; Becker, Heinz; Ganser, Arnold; Neumaier, Michael; Kaminski, Wolfgang E.

2011-01-01

39

Unique proteomic signatures distinguish macrophages and dendritic cells.  

PubMed

Monocytes differentiate into heterogeneous populations of tissue macrophages and dendritic cells (DCs) that regulate inflammation and immunity. Identifying specific populations of myeloid cells in vivo is problematic, however, because only a limited number of proteins have been used to assign cellular phenotype. Using mass spectrometry and bone marrow-derived cells, we provided a global view of the proteomes of M-CSF-derived macrophages, classically and alternatively activated macrophages, and GM-CSF-derived DCs. Remarkably, the expression levels of half the plasma membrane proteins differed significantly in the various populations of cells derived in vitro. Moreover, the membrane proteomes of macrophages and DCs were more distinct than those of classically and alternatively activated macrophages. Hierarchical cluster and dual statistical analyses demonstrated that each cell type exhibited a robust proteomic signature that was unique. To interrogate the phenotype of myeloid cells in vivo, we subjected elicited peritoneal macrophages harvested from wild-type and GM-CSF-deficient mice to mass spectrometric and functional analysis. Unexpectedly, we found that peritoneal macrophages exhibited many features of the DCs generated in vitro. These findings demonstrate that global analysis of the membrane proteome can help define immune cell phenotypes in vivo. PMID:22428014

Becker, Lev; Liu, Ning-Chun; Averill, Michelle M; Yuan, Wei; Pamir, Nathalie; Peng, Yufeng; Irwin, Angela D; Fu, Xiaoyun; Bornfeldt, Karin E; Heinecke, Jay W

2012-01-01

40

Unique Proteomic Signatures Distinguish Macrophages and Dendritic Cells  

PubMed Central

Monocytes differentiate into heterogeneous populations of tissue macrophages and dendritic cells (DCs) that regulate inflammation and immunity. Identifying specific populations of myeloid cells in vivo is problematic, however, because only a limited number of proteins have been used to assign cellular phenotype. Using mass spectrometry and bone marrow-derived cells, we provided a global view of the proteomes of M-CSF-derived macrophages, classically and alternatively activated macrophages, and GM-CSF-derived DCs. Remarkably, the expression levels of half the plasma membrane proteins differed significantly in the various populations of cells derived in vitro. Moreover, the membrane proteomes of macrophages and DCs were more distinct than those of classically and alternatively activated macrophages. Hierarchical cluster and dual statistical analyses demonstrated that each cell type exhibited a robust proteomic signature that was unique. To interrogate the phenotype of myeloid cells in vivo, we subjected elicited peritoneal macrophages harvested from wild-type and GM-CSF-deficient mice to mass spectrometric and functional analysis. Unexpectedly, we found that peritoneal macrophages exhibited many features of the DCs generated in vitro. These findings demonstrate that global analysis of the membrane proteome can help define immune cell phenotypes in vivo. PMID:22428014

Becker, Lev; Liu, Ning-Chun; Averill, Michelle M.; Yuan, Wei; Pamir, Nathalie; Peng, Yufeng; Irwin, Angela D.; Fu, Xiaoyun; Bornfeldt, Karin E.; Heinecke, Jay W.

2012-01-01

41

Networked T Cell Death following Macrophage Infection by Mycobacterium tuberculosis  

PubMed Central

Background Depletion of T cells following infection by Mycobacterium tuberculosis (Mtb) impairs disease resolution, and interferes with clinical test performance that relies on cell-mediated immunity. A number of mechanisms contribute to this T cell suppression, such as activation-induced death and trafficking of T cells out of the peripheral circulation and into the diseased lungs. The extent to which Mtb infection of human macrophages affects T cell viability however, is not well characterised. Methodology/Principal Findings We found that lymphopenia (<1.5×109 cells/l) was prevalent among culture-positive tuberculosis patients, and lymphocyte counts significantly improved post-therapy. We previously reported that Mtb-infected human macrophages resulted in death of infected and uninfected bystander macrophages. In the current study, we sought to examine the influence of infected human alveolar macrophages on T cells. We infected primary human alveolar macrophages (the primary host cell for Mtb) or PMA-differentiated THP-1 cells with Mtb H37Ra, then prepared cell-free supernatants. The supernatants of Mtb-infected macrophages caused dose-dependent, caspase-dependent, T cell apoptosis. This toxic effect of infected macrophage secreted factors did not require TNF-? or Fas. The supernatant cytotoxic signal(s) were heat-labile and greater than 50 kDa in molecular size. Although ESAT-6 was toxic to T cells, other Mtb-secreted factors tested did not influence T cell viability; nor did macrophage-free Mtb bacilli or broth from Mtb cultures. Furthermore, supernatants from Mycobacterium bovis Bacille de Calmette et Guerin (BCG)- infected macrophages also elicited T cell death suggesting that ESAT-6 itself, although cytotoxic, was not the principal mediator of T cell death in our system. Conclusions Mtb-Infected macrophages secrete heat-labile factors that are toxic to T cells, and may contribute to the immunosuppression seen in tuberculosis as well as interfere with microbial eradication in the granuloma. PMID:22675566

Macdonald, Stephen H.-F.; Woodward, Elliott; Coleman, Michelle M.; Dorris, Emma R.; Nadarajan, Parthiban; Chew, Wui-Mei; McLaughlin, Anne-Marie; Keane, Joseph

2012-01-01

42

Biofilm-derived Legionella pneumophila evades the innate immune response in macrophages  

PubMed Central

Legionella pneumophila, the causative agent of Legionnaire's disease, replicates in human alveolar macrophages to establish infection. There is no human-to-human transmission and the main source of infection is L. pneumophila biofilms established in air conditioners, water fountains, and hospital equipments. The biofilm structure provides protection to the organism from disinfectants and antibacterial agents. L. pneumophila infection in humans is characterized by a subtle initial immune response, giving time for the organism to establish infection before the patient succumbs to pneumonia. Planktonic L. pneumophila elicits a strong immune response in murine, but not in human macrophages enabling control of the infection. Interactions between planktonic L. pneumophila and murine or human macrophages have been studied for years, yet the interface between biofilm-derived L. pneumophila and macrophages has not been explored. Here, we demonstrate that biofilm-derived L. pneumophila replicates significantly more in murine macrophages than planktonic bacteria. In contrast to planktonic L. pneumophila, biofilm-derived L. pneumophila lacks flagellin expression, do not activate caspase-1 or -7 and trigger less cell death. In addition, while planktonic L. pneumophila is promptly delivered to lysosomes for degradation, most biofilm-derived bacteria were enclosed in a vacuole that did not fuse with lysosomes in murine macrophages. This study advances our understanding of the innate immune response to biofilm-derived L. pneumophila and closely reproduces the natural mode of infection in human. PMID:23750338

Abu Khweek, Arwa; Fernandez Davila, Natalia S.; Caution, Kyle; Akhter, Anwari; Abdulrahman, Basant A.; Tazi, Mia; Hassan, Hoda; Novotny, Laura A.; Bakaletz, Lauren O.; Amer, Amal O.

2013-01-01

43

Vaccination with Irradiated Tumor Cells Engineered to Secrete Murine Granulocyte-Macrophage Colony-Stimulating Factor Stimulates Potent, Specific, and Long-Lasting AntiTumor Immunity  

Microsoft Academic Search

To compare the ability of different cytokines and other molecules to enhance the immunogenicity of tumor cells, we generated 10 retroviruses encoding potential immunomodulators and studied the vaccination properties of murine tumor cells transduced by the viruses. Using a B16 melanoma model, in which irradiated tumor cells alone do not stimulate significant anti-tumor immunity, we found that irradiated tumor cells

Glenn Dranoff; Elizabeth Jaffee; Audrey Lazenby; Paul Golumbek; Hyam Levitsky; Katja Brose; Valerie Jackson; Hirofumi Hamada; Drew Pardoll; Richard C. Mulligan

1993-01-01

44

The role of human glioma-infiltrating microglia/macrophages in mediating antitumor immune responses1  

PubMed Central

Little is known about the immune performance and interactions of CNS microglia/macrophages in glioma patients. We found that microglia/macrophages were the predominant immune cell infiltrating gliomas (~1% of total cells); others identified were myeloid dendritic cells (DCs), plasmacytoid DCs, and T cells. We isolated and analyzed the immune functions of CD11b/c+CD45+ glioma-infiltrating microglia/macrophages (GIMs) from postoperative tissue specimens of glioma patients. Although GIMs expressed substantial levels of Toll-like receptors (TLRs), they did not appear stimulated to produce pro-inflammatory cytokines (tumor necrosis factor ?, interleukin 1, or interleukin 6), and in vitro, lipopolysaccharides could bind TLR-4 but could not induce GIM-mediated T-cell proliferation. Despite surface major histocompatibility complex class II expression, they lacked expression of the costimulatory molecules CD86, CD80, and CD40 critical for T-cell activation. Ex vivo, we demonstrate a corresponding lack of effector/activated T cells, as glioma-infiltrating CD8+ T cells were phenotypically CD8+CD25?. By contrast, there was a prominent population of regulatory CD4 T cells (CD4+CD25+FOXP3+) infiltrating the tumor. We conclude that while GIMs may have a few intact innate immune functions, their capacity to be stimulated via TLRs, secrete cytokines, upregulate costimulatory molecules, and in turn activate antitumor effector T cells is not sufficient to initiate immune responses. Furthermore, the presence of regulatory T cells may also contribute to the lack of effective immune activation against malignant human gliomas. PMID:16775224

Hussain, S. Farzana; Yang, David; Suki, Dima; Aldape, Kenneth; Grimm, Elizabeth; Heimberger, Amy B.

2006-01-01

45

Suppression of macrophage infiltration into the conjunctiva by clodronate liposomes in experimental immune-mediated blepharoconjunctivitis.  

PubMed

Macrophages infiltrate the conjunctiva in severe cases of allergic conjunctivitis (AC) such as atopic keratoconjunctivitis (AKC). We established experimental immune-mediated blepharoconjunctivitis (EC) in Brown Norway (BN) rats as a model for severe types of AC. We investigated whether macrophage infiltration in the conjunctiva in this EC model is inhibited by clodronate liposomes (CL2MDP-lip). The numbers of ED1-positive but not ED2-positive macrophages in the conjunctivas were increased by the induction of EC. Subconjunctival injection of CL2MDP-lip decreased the number of ED2-positive but not ED1-positive macrophages in the conjunctivas of naive rats. CL2MDP-lip did not affect macrophages in the spleen. Subconjunctival injection of CL2MDP-lip into EC-developing BN rats decreased the number of ED2-positive macrophages at all the time points. ED1-positive cell infiltration was inhibited when treatment was administered just prior to OVA challenge. Intravenous injection of CL2MDP-lip decreased the number of ED2-positive cells in the conjunctiva. Thus, we conclude that CL2MDP-lip inhibits infiltration of macrophages into the conjunctiva within 24 h of antigen challenge. PMID:15893479

Fukushima, Atsuki; Ozaki, Akemi; Ishida, Waka; van Rooijen, Nico; Fukata, Kazuyo; Ueno, Hisayuki

2005-04-01

46

Of macrophages and red blood cells; a complex love story.  

PubMed

Macrophages tightly control the production and clearance of red blood cells (RBC). During steady state hematopoiesis, approximately 10(10) RBC are produced per hour within erythroblastic islands in humans. In these erythroblastic islands, resident bone marrow macrophages provide erythroblasts with interactions that are essential for erythroid development. New evidence suggests that not only under homeostasis but also under stress conditions, macrophages play an important role in promoting erythropoiesis. Once RBC have matured, these cells remain in circulation for about 120 days. At the end of their life span, RBC are cleared by macrophages residing in the spleen and the liver. Current theories about the removal of senescent RBC and the essential role of macrophages will be discussed as well as the role of macrophages in facilitating the removal of damaged cellular content from the RBC. In this review we will provide an overview on the role of macrophages in the regulation of RBC production, maintenance and clearance. In addition, we will discuss the interactions between these two cell types during transfer of immune complexes and pathogens from RBC to macrophages. PMID:24523696

de Back, Djuna Z; Kostova, Elena B; van Kraaij, Marian; van den Berg, Timo K; van Bruggen, Robin

2014-01-01

47

Of macrophages and red blood cells; a complex love story  

PubMed Central

Macrophages tightly control the production and clearance of red blood cells (RBC). During steady state hematopoiesis, approximately 1010 RBC are produced per hour within erythroblastic islands in humans. In these erythroblastic islands, resident bone marrow macrophages provide erythroblasts with interactions that are essential for erythroid development. New evidence suggests that not only under homeostasis but also under stress conditions, macrophages play an important role in promoting erythropoiesis. Once RBC have matured, these cells remain in circulation for about 120 days. At the end of their life span, RBC are cleared by macrophages residing in the spleen and the liver. Current theories about the removal of senescent RBC and the essential role of macrophages will be discussed as well as the role of macrophages in facilitating the removal of damaged cellular content from the RBC. In this review we will provide an overview on the role of macrophages in the regulation of RBC production, maintenance and clearance. In addition, we will discuss the interactions between these two cell types during transfer of immune complexes and pathogens from RBC to macrophages. PMID:24523696

de Back, Djuna Z.; Kostova, Elena B.; van Kraaij, Marian; van den Berg, Timo K.; van Bruggen, Robin

2013-01-01

48

Chemoattractant Signaling between Tumor Cells and Macrophages Regulates Cancer Cell Migration, Metastasis and Neovascularization  

Microsoft Academic Search

Tumor-associated macrophages are known to influence cancer progression by modulation of immune function, angiogenesis, and cell metastasis, however, little is known about the chemokine signaling networks that regulate this process. Utilizing CT26 colon cancer cells and RAW 264.7 macrophages as a model cellular system, we demonstrate that treatment of CT26 cells with RAW 264.7 conditioned medium induces cell migration, invasion

Chad E. Green; Tiffany Liu; Valerie Montel; Gene Hsiao; Robin D. Lester; Shankar Subramaniam; Steven L. Gonias; Richard L. Klemke

2009-01-01

49

Immune Evasion, Stress Resistance, and Efficient Nutrient Acquisition Are Crucial for Intracellular Survival of Candida glabrata within Macrophages  

PubMed Central

Candida glabrata is both a human fungal commensal and an opportunistic pathogen which can withstand activities of the immune system. For example, C. glabrata can survive phagocytosis and replicates within macrophages. However, the mechanisms underlying intracellular survival remain unclear. In this work, we used a functional genomic approach to identify C. glabrata determinants necessary for survival within human monocyte-derived macrophages by screening a set of 433 deletion mutants. We identified 23 genes which are required to resist killing by macrophages. Based on homologies to Saccharomyces cerevisiae orthologs, these genes are putatively involved in cell wall biosynthesis, calcium homeostasis, nutritional and stress response, protein glycosylation, or iron homeostasis. Mutants were further characterized using a series of in vitro assays to elucidate the genes' functions in survival. We investigated different parameters of C. glabrata-phagocyte interactions: uptake by macrophages, replication within macrophages, phagosomal pH, and recognition of mutant cells by macrophages as indicated by production of reactive oxygen species and tumor necrosis factor alpha (TNF-?). We further studied the cell surface integrity of mutant cells, their ability to grow under nutrient-limited conditions, and their susceptibility to stress conditions mirroring the harsh environment inside a phagosome. Additionally, resistance to killing by neutrophils was analyzed. Our data support the view that immune evasion is a key aspect of C. glabrata virulence and that increased immune recognition causes increased antifungal activities by macrophages. Furthermore, stress resistance and efficient nutrient acquisition, in particular, iron uptake, are crucial for intraphagosomal survival of C. glabrata. PMID:24363366

Seider, Katja; Gerwien, Franziska; Kasper, Lydia; Allert, Stefanie; Brunke, Sascha; Jablonowski, Nadja; Schwarzmüller, Tobias; Barz, Dagmar; Rupp, Steffen; Kuchler, Karl

2014-01-01

50

Neonatal macrophages express elevated levels of interleukin-27 that oppose immune responses  

PubMed Central

Microbial infections are a major cause of infant mortality worldwide because of impaired immune defences in this population. The nature of this work was to further understand the mechanistic limitations of the neonatal and infant immune response. Interleukin-27 (IL-27) is a heterodimeric cytokine of the IL-12 family that is produced primarily by antigen-presenting cells and is immunosuppressive toward a variety of immune cell types. We show that IL-27 gene expression is elevated in cord blood-derived macrophages relative to macrophages originating from healthy adults. We also evaluated the duration over which elevated IL-27 gene expression may impact immune responses in mice. Age-dependent analysis of IL-27 gene expression indicated that levels of IL-27 remained significantly elevated throughout infancy and then declined in adult mice. Flow cytometric analysis of intracellular cytokine-stained splenocytes further confirmed these results. Interleukin-27 may be induced during pregnancy to contribute to the immunosuppressive environment at the fetal–maternal interface because we demonstrate dose-responsive gene expression to progesterone in macrophages. Neutralization of IL-27 in neonatal macrophages improved the ability of these cells to limit bacterial replication. Moreover, neutralization of IL-27 during incubation with the Mycobacterium bovis bacillus Calmette–Guérin vaccine augmented the level of interferon-? elicited from allogeneic CD4+ T lymphocytes. This suggests that blocking IL-27 during vaccination and infection may improve immune responses in newborn and infant populations. Furthermore, mice will be a suitable model system to further address these possibilities. PMID:23464355

Kraft, Jennifer D; Horzempa, Joseph; Davis, Celestia; Jung, Joo-Yong; Pena, Maria Marjorette O; Robinson, Cory M

2013-01-01

51

GM-CSF Regulates Alveolar Macrophage Differentiation and Innate Immunity in the Lung through PU.1  

Microsoft Academic Search

GM-CSF gene targeted (GM?\\/?) mice are susceptible to respiratory infections and develop alveolar proteinosis due to defects in innate immune function and surfactant catabolism in alveolar macrophages (AMs), respectively. Reduced cell adhesion, phagocytosis, pathogen killing, mannose- and Toll-like receptor expression, and LPS- or peptidoglycan-stimulated TNF? release were observed in AMs from GM?\\/? mice. The transcription factor PU.1 was markedly reduced

Yoko Shibata; Pierre-Yves Berclaz; Zissis C Chroneos; Mitsuhiro Yoshida; Jeffrey A Whitsett; Bruce C Trapnell

2001-01-01

52

Non-immunogenic Murine Hepatocellular Carcinoma Hepa1-6 Cells Expressing the Membrane Form of Macrophage Colony Stimulating Factor Are Rejected in Vivo and Lead to CD8+ T-Cell Immunity Against the Parental Tumor  

Microsoft Academic Search

Hepatocellular carcinoma is a lethal disease and methods that develop effective cellular-based immunotherapy are needed. We retrovirally transduced non-immunogenic mouse Hepa1-6 hepatoma cells with the gene encoding the membrane form of macrophage colony stimulating factor (mM-CSF). Excess recombinant M-CSF and phagocytosis-inhibiting chemicals blocked macrophage-mediated killing of cloned mM-CSF transfected Hepa1-6 hepatoma cells. Macrophages derived from Hck-\\/-Fgr-\\/- and Lyn-\\/- triple knockout

Qinghong Dan; Ramon Sanchez; Christina Delgado; H. Terry Wepsic; Kengathevy Morgan; Yijun Chen; Edward W. B. Jeffes; Clifford A. Lowell; Timothy R. Morgan; Martin R. Jadus

2001-01-01

53

Immune cells in term and preterm labor  

PubMed Central

Labor resembles an inflammatory response that includes secretion of cytokines/chemokines by resident and infiltrating immune cells into reproductive tissues and the maternal/fetal interface. Untimely activation of these inflammatory pathways leads to preterm labor, which can result in preterm birth. Preterm birth is a major determinant of neonatal mortality and morbidity; therefore, the elucidation of the process of labor at a cellular and molecular level is essential for understanding the pathophysiology of preterm labor. Here, we summarize the role of innate and adaptive immune cells in the physiological or pathological activation of labor. We review published literature regarding the role of innate and adaptive immune cells in the cervix, myometrium, fetal membranes, decidua and the fetus in late pregnancy and labor at term and preterm. Accumulating evidence suggests that innate immune cells (neutrophils, macrophages and mast cells) mediate the process of labor by releasing pro-inflammatory factors such as cytokines, chemokines and matrix metalloproteinases. Adaptive immune cells (T-cell subsets and B cells) participate in the maintenance of fetomaternal tolerance during pregnancy, and an alteration in their function or abundance may lead to labor at term or preterm. Also, immune cells that bridge the innate and adaptive immune systems (natural killer T (NKT) cells and dendritic cells (DCs)) seem to participate in the pathophysiology of preterm labor. In conclusion, a balance between innate and adaptive immune cells is required in order to sustain pregnancy; an alteration of this balance will lead to labor at term or preterm. PMID:24954221

Gomez-Lopez, Nardhy; StLouis, Derek; Lehr, Marcus A; Sanchez-Rodriguez, Elly N; Arenas-Hernandez, Marcia

2014-01-01

54

Immune regulation of 1alpha-hydroxylase in murine peritoneal macrophages: unravelling the IFNgamma pathway.  

PubMed

The activated form of vitamin D(3), 1,25-dihydroxyvitamin D(3) (1,25(OH)(2)D(3)), plays an important role in the immune system. Indeed, receptors for 1,25(OH)(2)D(3) are found on most immune cells, and 1alpha-hydroxylase, the enzyme responsible for final activation of vitamin D(3), is expressed by monocytes/macrophages, resulting in secretion of 1,25(OH)(2)D(3) after immune stimulation. We have previously shown that in murine peritoneal macrophages 1alpha-hydroxylase is highly regulated by immune signals such as IFNgamma and LPS. In the present study we made use of two different knock-out mouse models with disruptions in two key transcription factors in the IFNgamma-signalling cascade (STAT1alpha and IRF1), to evaluate their role in the regulation of 1alpha-hydroxylase. This was performed by culturing peritoneal macrophages from these knock-out mice in the presence of IFNgamma and LPS, and evaluating the impact of the absence of the respective transcription factors on 1alpha-hydroxylase mRNA expression by real-time RT-PCR. In addition also the mRNA expression profiles of the essential transcription factors STAT1alpha, IRF1 and C/EBPbeta were investigated. The data confirm a crucial role for STAT1alpha as well as for C/EBPbeta in the regulation of 1alpha-hydroxylase in monocytes. PMID:17267208

Stoffels, K; Overbergh, L; Bouillon, R; Mathieu, C

2007-03-01

55

Detection of Mutant-specific Responses by Macrophage Migration Inhibition Reactions Induced by Wild-type and Mutant Polyoma Viruses and Polyoma Virus-infected Cells1  

Microsoft Academic Search

Macrophage migration inhibition responses of mice immunized with mutant polyoma viruses or with cells transformed and\\/or infected by them have been studied. The macrophage migration inhibition reaction revealed individual differences. In several cases, mice immunized with a mutant virus responded prefer entially or exclusively to extracts of cells transformed or infected with the corresponding mutant. Moreover, in the macrophage migration

Robert Szigeti; Tina Dalianis; Yoshiaki Ito; George Klein

1984-01-01

56

An influx of macrophages is the predominant local immune response in ovine pulmonary adenocarcinoma.  

PubMed

Infection with a retrovirus, Jaagsiekte sheep retrovirus (JSRV), causes ovine pulmonary adenocarcinoma (OPA). The excess production of surfactant proteins by alveolar tumour cells results in increased production of pulmonary fluid, which is characteristically expelled through the nostrils of affected sheep. The immune response to JSRV and the tumour is poorly understood: no JSRV-specific circulating antibodies or T cells have been detected to date. The aim of the present study was to obtain phenotypic evidence for a local immune response in OPA lungs. Specific-pathogen free lambs were infected intratracheally with JSRV. When clinical signs of OPA were apparent, the lungs were removed at necropsy and immunohistochemistry (IHC) was performed on lung sections using a panel of mouse anti-sheep mAbs. No influx of dendritic cells, B cells, CD4, CD8 or gammadelta T cells was seen in the neoplastic nodules or in their periphery. MHC Class II-positive cells were found intratumourally, peritumourally and in the surrounding alveolar lumina. In the tumours, many of these cells were shown to be fibroblasts and the remainder were likely to be mature macrophages. In the alveolar lumen, the MHC Class II-positive cells were CD14-positive and expressed high levels of IFN-gamma. They appeared to be immature monocytes or macrophages which then differentiated to become CD14-negative as they reached the periphery of the tumours. A high level of MHC Class I expression was detected on a range of cells in the OPA lungs but the tumour nodules themselves contained no MHC Class I-positive cells. On the basis of these findings, it is proposed that the lack of an effective immune response in OPA could result from a mechanism of peripheral tolerance in which the activity of the invading macrophages is suppressed by the local environment, possibly as a consequence of the inhibitory properties of the surfactant proteins. PMID:15878202

Summers, C; Norval, M; De Las Heras, M; Gonzalez, L; Sharp, J M; Woods, G M

2005-07-15

57

Cross-protective immune responses induced in rhesus macaques by immunization with attenuated macrophage-tropic simian immunodeficiency virus.  

PubMed Central

The simian immunodeficiency virus (SIV) macaque model of AIDS has provided a valuable system with which to investigate vaccine approaches for protection against human immunodeficiency virus type 1 (HIV-1) infection. In particular, the ability of macaques persistently infected with attenuated infectious molecular clones of SIV to resist challenge with the pathogenic parental swarm has conclusively demonstrated that protective immunity can be achieved by immunization prior to exposure. The breadth of these protective responses and the immunological correlates of protection, however, have not been identified. In addition, vaccine studies have mainly employed lymphocyte-tropic strains of HIV-1 and SIV. Recent studies have implicated macrophage-tropic strains in the transmission of HIV-1 and have suggested that these virus strains should be examined in vaccine strategies. Macrophage-tropic viruses may confer additional advantages in the induction of protective immunity by replication in antigen-presenting cells. In this study, the immune response of rhesus macaques inoculated with an attenuated macrophage-tropic recombinant of SIVmac239 (SIV/17E-Cl) was evaluated with respect to protective immunity by heterologous challenge at various times after infection. Vigorous type-specific neutralizing-antibody responses restricted to SIV/17E-Cl were evident by 2 weeks postinfection. By 7 months, however, cross-reactive neutralizing antibodies emerged which neutralized not only SIV/17E-Cl but also the heterologous primary isolate SIV/DeltaB670. Challenge of SIV/17E-Cl-infected monkeys with SIV/DeltaB670 at various times postinfection demonstrated that protective responses were associated with the appearance of cross-reactive neutralizing antibodies. Furthermore, passive transfer of sera from SIV/17E-Cl-infected animals passively protected two of four naive recipients. PMID:7707496

Clements, J E; Montelaro, R C; Zink, M C; Amedee, A M; Miller, S; Trichel, A M; Jagerski, B; Hauer, D; Martin, L N; Bohm, R P

1995-01-01

58

Diverse influences of androgen-disrupting chemicals on immune responses mounted by macrophages.  

PubMed

Androgen-disrupting chemicals (ADCs) can alter male sexual development. Although the effects of ADCs on hormone disruption have been studied, their influence on the immune response is not fully understood. To investigate the effects of ADCs on innate immunity, we tested eight candidate ADCs for their influence on macrophages by measuring nitric oxide (NO) production and cell viability. Our results showed that treatment with a mixture of lipopolysaccharide and hexachlorobenzene increased NO production in RAW 264.7 cells, a murine macrophage cell line. In contrast, compared to exposure to a negative control, exposure to di-2-ethylhexyl adipate (DEHA), benzylbutyl phthalate (BBP), testosterone (TTT), or permethrin decreased NO production. DEHA, BBP, and TTT inhibited NO production in an inducible nitric oxide synthase-dependent manner. Treatment with bisphenol A (BPA), nonylphenol (NNP), or tributyltin chloride (TBTC) reduced NO production and induced cell death. While BPA induced RAW 264.7 cell death through apoptosis, NNP and TBTC caused cell death through necrosis. These results offer insights into the influences of ADCs on the innate immune system. PMID:24287822

Kim, Kyong Hoon; Yeon, Seung-min; Kim, Hyun Gyung; Choi, Hyun Suk; Kang, Hyojeung; Park, Hee-Deung; Park, Tae Won; Pack, Seung Pil; Lee, Eun Hee; Byun, Youngjoo; Choi, Sang-Eun; Lee, Kenneth Sung; Ha, Un-Hwan; Jung, Yong Woo

2014-06-01

59

Macrophages: supportive cells for tissue repair and regeneration.  

PubMed

Macrophages, and more broadly inflammation, have been considered for a long time as bad markers of tissue homeostasis. However, if it is indisputable that macrophages are associated with many diseases in a deleterious way, new roles have emerged, showing beneficial properties of macrophages during tissue repair and regeneration. This discrepancy is likely due to the high plasticity of macrophages, which may exhibit a wide range of phenotypes and functions depending on their environment. Therefore, regardless of their role in immunity, macrophages play a myriad of roles in the maintenance and recovery of tissue homeostasis. They take a major part in the resolution of inflammation. They also exert various effects of parenchymal cells, including stem and progenitor cell, of which they regulate the fate. In the present review, few examples from various tissues are presented to illustrate that, beyond their specific properties in a given tissue, common features have been described that sustain a role of macrophages in the recovery and maintenance of tissue homeostasis. PMID:24080029

Chazaud, Bénédicte

2014-03-01

60

T Cell-Macrophage Interactions and Granuloma Formation in Vasculitis  

PubMed Central

Granuloma formation, bringing into close proximity highly activated macrophages and T cells, is a typical event in inflammatory blood vessel diseases, and is noted in the name of several of the vasculitides. It is not known whether specific properties of the microenvironment in the blood vessel wall or the immediate surroundings of blood vessels contribute to granuloma formation and, in some cases, generation of multinucleated giant cells. Granulomas provide a specialized niche to optimize macrophage–T cell interactions, strongly activating both cell types. This is mirrored by the intensity of the systemic inflammation encountered in patients with vasculitis, often presenting with malaise, weight loss, fever, and strongly upregulated acute phase responses. As a sophisticated and highly organized structure, granulomas can serve as an ideal site to induce differentiation and maturation of T cells. The granulomas possibly seed aberrant Th1 and Th17 cells into the circulation, which are known to be the main pathogenic cells in vasculitis. Through the induction of memory T cells, aberrant innate immune responses can imprint the host immune system for decades to come and promote chronicity of the disease process. Improved understanding of T cell–macrophage interactions will redefine pathogenic models in the vasculitides and provide new avenues for immunomodulatory therapy. PMID:25309534

Hilhorst, Marc; Shirai, Tsuyoshi; Berry, Gerald; Goronzy, Jorg J.; Weyand, Cornelia M.

2014-01-01

61

To Study the Effect of Paclitaxel on the Cytoplasmic Viscosity of Murine Macrophage Immune Cell RAW 264.7 Using Self-Developed Optical Tweezers System  

NASA Astrophysics Data System (ADS)

In recent years, optical tweezers have become one of the tools to measure the mechanical properties of living cells. In this study, we first constructed an optical tweezers to investigate the cytoplasmic viscosity of immune cells. In addition to measuring viscosity of cells in a normal condition, we also treated cells with anti-cancer drug, Paclitaxel, and in order to study its effect on the cytoplasmic viscosity. The results showed that the viscosity decreased dramatically during the first 3 h. After 3 h, the change started to slow down and it remained nearly flat by the end of the experiment. In addition, we used the confocal laser scanning microscope to observe the cytoskeleton of the cell after drug treatment for 3 and 5 h, respectively, and found that actin filaments were disrupted and that the nucleus had disintegrated in some drug-treated cells, similar to the process of apoptosis. This study presents a new way for measuring the changes in cytoplasmic viscosity, and to determine if a cell is going into apoptosis as a result of a drug treatment.

Chen, Ying-chun; Wu, Chien-ming

2012-12-01

62

Interleukin-4-induced ?-catenin regulates the conversion of macrophages to multinucleated giant cells  

PubMed Central

The cytokine interleukin-4 (IL-4) exerts pleiotropic effects on macrophages as it plays a key role in the immune response to infectious agents, allergens, and vaccines. Macrophages exposed to IL-4 drastically change their gene expression and metabolic state to adjust to new functional requirements. IL-4 also induces macrophages to fuse together and form multinucleated giant cells (MGCs). MGC formation is associated with chronic inflammation resulting from persistence of pathogenic microorganisms or foreign materials in tissues. Very little is known, however, about the mechanisms regulating IL-4-induced macrophage-to-MGC conversion. We observed a dramatic increase in ?-catenin protein but not mRNA amount in mouse macrophages following exposure to IL-4. To investigate the role of ?-catenin in macrophages, we generated mice with a myeloid cell-specific deletion of the ?-catenin gene. Ablation of ?-catenin expression did not affect the viability of macrophages or impair expression of known IL-4-inducible genes. Intriguingly, ?-catenin-deficient macrophages incubated with IL-4 formed MGCs with markedly greater efficiency than wild-type macrophages. Similar increases in multinucleated cell formation were detected in the peritoneal cavity of myeloid cell-specific ?-catenin knockout mice injected with chitin, which is known to induce endogenous IL-4 production. Our findings reveal ?-catenin as a novel regulator of macrophage responses to IL-4, and suggest that therapeutic modulation of its expression or function may help enhance the effectiveness or ameliorate the pathology of IL-4-driven immune responses. PMID:23287596

Binder, Flora; Hayakawa, Morisada; Choo, Min-Kyung; Sano, Yasuyo; Park, Jin Mo

2012-01-01

63

Kinase AKT controls innate immune cell development and function  

PubMed Central

The critical roles of kinase AKT in tumour cell proliferation, apoptosis and protein synthesis have been widely recognized. But AKT also plays an important role in immune modulation. Recent studies have confirmed that kinase AKT can regulate the development and functions of innate immune cells (neutrophil, macrophage and dendritic cell). Studies have shown that different isoforms of kinase AKT have different effects in regulating immunity-related diseases, mainly through the mammalian target of rapamycin-dependent or -independent pathways. The purpose of this review is to illustrate the immune modulating effects of kinase AKT on innate immune cell development, survival and function. PMID:23692658

Zhang, Yan; Wang, Xiao; Yang, Hui; Liu, Huanrong; Lu, Yun; Han, Limei; Liu, Guangwei

2013-01-01

64

Immune cells tracing using quantum dots  

NASA Astrophysics Data System (ADS)

Fluorescent nanoparticles, such as nanocrystal quantum dots (QDs), have potential to be applied to molecular biology and bioimaging, since some nanocrystals emit higher and longer lasting fluorescence than conventional organic probes do. Here we report an example of labeling immune cells by QDs. We collected splenic CD4 + T-lymphocyte and peritoneal macrophages from mice. Then cells were labeled with QDs. QDs are incorporated into the T-lymphocyte and macrophages immediately after addition and located in the cytoplasm via endocytosis pathway. The fluorescence of QDs held in the endosomes was easily detected for more than a week. In addition, T-lymphocytes labeled with QDs were stable and cell proliferation or cytokine production including IL-2 and IFN-? was not affected. When QD-labeled T-lymphocytes were adoptively transferred intravenously to mice, they remained in the peripheral blood and spleen up to a week. Using QD-labeled peritoneal macrophages, we studied cell traffic during inflammation on viscera in peritoneum cavity. QD-labeled macrophages were transplanted into the peritoneum of the mouse, and colitis was induced by intracolonic injection of a hapten, trinitrobenzensulfonic acid. With the aid of stong signals of QDs, we found that macrophage accumuled on the inflammation site of the colon. These results suggested that fluorescent probes of QDs might be useful as bioimaging tools for tracing target cells in vivo.

Hoshino, Akiyoshi; Fujioka, Kouki; Kawamura, Yuki I.; Toyama-Sorimachi, Noriko; Yasuhara, Masato; Dohi, Taeko; Yamamoto, Kenji

2006-02-01

65

Cell-cell contacts with epithelial cells modulate the phenotype of human macrophages.  

PubMed

Interactions of macrophages with epithelium represent one of the pathways involved in regulating local immune mechanisms. We studied the effect of cell-cell contact with an epithelial monolayer on the phenotype of macrophages. Human monocytes and THP-1 macrophages were co-cultured with monolayers of human bronchial epithelial cells (HBECs), the alveolar type II-like cell line A549, renal adenocarcinoma epithelial cells (RA), and the lung fibroblast strain HFL-1. The expression of CD11b, CD14, CD54, and HLA-DR was measured by immunocytochemistry and flow cytometry and showed epithelial cell induction of CD54 and HLA-DR in monocytes and of all antigens in THP-1 cells. Co-culture with fibroblasts did not change the phenotype of macrophages. Separation by a filter insert inhibited most of the effects. Culture supernatants did not induce prominent phenotypic changes. Cell-cell contacts with epithelium appear to be of importance in regulating the phenotype of macrophages. PMID:11580100

Striz, I; Slavcev, A; Kalanin, J; Jaresová, M; Rennard, S I

2001-08-01

66

Innate Immune Cells in Liver Inflammation  

PubMed Central

Innate immune system is the first line of defence against invading pathogens that is critical for the overall survival of the host. Human liver is characterised by a dual blood supply, with 80% of blood entering through the portal vein carrying nutrients and bacterial endotoxin from the gastrointestinal tract. The liver is thus constantly exposed to antigenic loads. Therefore, pathogenic microorganism must be efficiently eliminated whilst harmless antigens derived from the gastrointestinal tract need to be tolerized in the liver. In order to achieve this, the liver innate immune system is equipped with multiple cellular components; monocytes, macrophages, granulocytes, natural killer cells, and dendritic cells which coordinate to exert tolerogenic environment at the same time detect, respond, and eliminate invading pathogens, infected or transformed self to mount immunity. This paper will discuss the innate immune cells that take part in human liver inflammation, and their roles in both resolution of inflammation and tissue repair. PMID:22933833

Liaskou, Evaggelia; Wilson, Daisy V.; Oo, Ye H.

2012-01-01

67

Sterols and oxysterols in immune cell function.  

PubMed

Intermediates in the cholesterol-biosynthetic pathway and oxysterol derivatives of cholesterol regulate diverse cellular processes. Recent studies have expanded the appreciation of their roles in controlling the functions of cells of the innate and adaptive immune systems. Here we review recent literature reporting on the biological functions of sterol intermediates and oxysterols, acting through transcription factors such as the liver X receptors (LXRs), sterol regulatory element-binding proteins (SREBPs) and the G protein-coupled receptor EBI2, in regulating the differentiation and population expansion of cells of the innate and adaptive immune systems, their responses to inflammatory mediators, their effects on the phagocytic functions of macrophages and their effects on antiviral activities and the migration of immune cells. Such findings have raised many new questions about the production of endogenous bioactive sterols and oxysterols and their mechanisms of action in the immune system. PMID:23959186

Spann, Nathanael J; Glass, Christopher K

2013-09-01

68

20S-dihydroprotopanaxadiol, a ginsenoside derivative, boosts innate immune responses of monocytes and macrophages  

PubMed Central

20S-dihydroprotopanaxadiol (2H-PPD) is a derivative of protopanaxadiol, a glycone of ginsenosides prepared from Panax ginseng. Although ginsenosides and acidic polysaccharides are known to be major active ingredients in ginseng, the immunopharmacological activities of their metabolites and derivatives have not been fully explored. In this study, we aimed to elucidate the regulatory action of 2H-PPD on the function of monocytes and macrophages in innate immune responses. 2H-PPD was able to boost the phagocytic uptake of fluorescein isothiocyanate-dextran in macrophages and enhance the generation of radicals (reactive oxygen species) in sodium nitroprusside-treated RAW264.7 cells. The surface levels of the costimulatory molecules such as CD80 and CD86 were also increased during 2H-PPD treatment. In addition, this compound boosted U937 cellcell aggregation induced by CD29 and CD43 antibodies, but not by cell-extracellular matrix (fibronectin) adhesion. Similarly, the surface levels of CD29 and CD43 were increased by 2H-PPD exposure. Therefore, our results strongly suggest that 2H-PPD has the pharmacological capability to upregulate the functional role of macrophages/monocytes in innate immunity. PMID:24198654

Kim, Mi-Yeon; Cho, Jae Youl

2013-01-01

69

Induction of Rapid T Cell Death and Phagocytic Activity by Fas-Deficient lpr Macrophages  

PubMed Central

Peripheral T cells are maintained by the apoptosis of activated T cells through the Fas–Fas ligand system. Although it is well known that normal T cells fail to survive in the Fas-deficient immune condition, the molecular mechanism for the phenomenon has yet to be elucidated. In this study, we demonstrate that rapid cell death and clearance of normal T cells were induced by Fas-deficient lpr macrophages. Transfer of normal T cells into lpr mice revealed that Fas expression on donor T cells was promptly enhanced through the IFN-?/IFN-?R. In addition, Fas ligand expression and phagocytic activity of lpr macrophages were promoted through increased NF-?B activation. Controlling Fas expression on macrophages plays an essential role in maintaining T cell homeostasis in the peripheral immune system. Our data suggest a critical implication to the therapeutic strategies such as transplantation and immunotherapy for immune disorder or autoimmunity related to abnormal Fas expression. PMID:23255359

Oura, Ritsuko; Arakaki, Rieko; Yamada, Akiko; Kudo, Yasusei; Tanaka, Eiji; Hayashi, Yoshio

2013-01-01

70

Receptor signaling in immune cell development and function  

PubMed Central

Immune cell development and function must be tightly regulated through cell surface receptors to ensure proper responses to pathogen and tolerance to self. In T cells, the signal from the T-cell receptor is essential for T-cell maturation, homeostasis, and activation. In mast cells, the high-affinity receptor for IgE transduces signal that promotes mast cell survival and induces mast cell activation. In dendritic cells and macrophages, the toll-like receptors recognize microbial pathogens and play critical roles for both innate and adaptive immunity against pathogens. Our research explores how signaling from these receptors is transduced and regulated to better understand these immune cells. Our recent studies have revealed diacylglycerol kinases and TSC1/2-mTOR as critical signaling molecules/regulators in T cells, mast cells, dendritic cells, and macrophages. PMID:21128010

Shin, Jinwook; Gorentla, Balachandra K.; O'Brien, Tommy; Srivatsan, Sruti; Xu, Li; Chen, Yong; Xie, Danli; Pan, Hongjie

2011-01-01

71

Nanogel-based immunologically stealth vaccine targets macrophages in the medulla of lymph node and induces potent antitumor immunity.  

PubMed

Because existing therapeutic cancer vaccines provide only a limited clinical benefit, a different vaccination strategy is necessary to improve vaccine efficacy. We developed a nanoparticulate cancer vaccine by encapsulating a synthetic long peptide antigen within an immunologically inert nanoparticulate hydrogel (nanogel) of cholesteryl pullulan (CHP). After subcutaneous injection to mice, the nanogel-based vaccine was efficiently transported to the draining lymph node, and was preferentially engulfed by medullary macrophages but was not sensed by other macrophages and dendritic cells (so-called "immunologically stealth mode"). Although the function of medullary macrophages in T cell immunity has been unexplored so far, these macrophages effectively cross-primed the vaccine-specific CD8(+) T cells in the presence of a Toll-like receptor (TLR) agonist as an adjuvant. The nanogel-based vaccine significantly inhibited in vivo tumor growth in the prophylactic and therapeutic settings, compared to another vaccine formulation using a conventional delivery system, incomplete Freund's adjuvant. We also revealed that lymph node macrophages were highly responsive to TLR stimulation, which may underlie the potency of the macrophage-oriented, nanogel-based vaccine. These results indicate that targeting medullary macrophages using the immunologically stealth nanoparticulate delivery system is an effective vaccine strategy. PMID:25180962

Muraoka, Daisuke; Harada, Naozumi; Hayashi, Tae; Tahara, Yoshiro; Momose, Fumiyasu; Sawada, Shin-ichi; Mukai, Sada-atsu; Akiyoshi, Kazunari; Shiku, Hiroshi

2014-09-23

72

NOD macrophages produce high levels of inflammatory cytokines upon encounter of apoptotic or necrotic cells.  

PubMed

During the development of type 1 diabetes, pancreatic beta-cells are subject to an immune attack, leading to their apoptotic or necrotic cell death. Apoptotic beta-cells are also present during periods of tissue remodeling, such as in early life. Macrophages should clear apoptotic cells silently without production of pro-inflammatory cytokines. The aim of the present study was to investigate the cytokine pattern of NOD macrophages exposed to apoptotic or necrotic cells in vitro. In contrast to the limited response of macrophages from C57BL/6 or NOR mice, NOD macrophages reacted aberrantly to both necrotic and apoptotic cells, with secretion of inappropriately high amounts of IL1beta and TNFalpha. Further exploration of the macrophage behavior showed an excessive response of NOD macrophages when exposed to LPS (high iNOS and IL12p40 levels), accompanied by hyper-activation of NF-kappaB(p65). In contrast, NOD macrophages failed to up-regulate IL1beta and IL12p40 in response to IFNgamma. This failure correlated with low protein levels and a low phosphorylation state of STAT1alpha. We conclude that NOD macrophages have severely aberrant cytokine expression patterns that could contribute to the initiation or continuation of an immune attack towards the pancreatic beta-cells and thus onset and progression of type 1 diabetes. PMID:15236748

Stoffels, K; Overbergh, L; Giulietti, A; Kasran, A; Bouillon, R; Gysemans, C; Mathieu, C

2004-08-01

73

Control of growth and inflammatory response of macrophages and foam cells with nanotopography  

PubMed Central

Macrophages play an important role in modulating the immune function of the human body, while foam cells differentiated from macrophages with subsequent fatty streak formation play a key role in atherosclerosis. We hypothesized that nanotopography modulates the behavior and function of macrophages and foam cells without bioactive agent. In the present study, nanodot arrays ranging from 10? to 200?nm were used to evaluate the growth and function of macrophages and foam cells. In the quantitative analysis, the cell adhesion area in macrophages increased with 10- to 50-nm nanodot arrays compared to the flat surface, while it decreased with 100- and 200-nm nanodot arrays. A similar trend of adhesion was observed in foam cells. Immunostaining, specific to vinculin and actin filaments, indicated that a 50-nm surface promoted cell adhesion and cytoskeleton organization. On the contrary, 200-nm surfaces hindered cell adhesion and cytoskeleton organization. Further, based on quantitative real-time polymerase chain reaction data, expression of inflammatory genes was upregulated for the 100- and 200-nm surfaces in macrophages and foam cells. This suggests that nanodots of 100??and 200?nm triggered immune inflammatory stress response. In summary, nanotopography controls cell morphology, adhesions, and proliferation. By adjusting the nanodot diameter, we could modulate the growth and expression of function-related genes in the macrophages and foam cell system. The nanotopography-mediated control of cell growth and morphology provides potential insight for designing cardiovascular implants. PMID:22799434

2012-01-01

74

Human IL23-producing type 1 macrophages promote but IL10-producing type 2 macrophages subvert immunity to (myco)bacteria  

Microsoft Academic Search

Macrophages (Mphi) play a central role as effector cells in immunity to intracellular pathogens such as Mycobacterium. Paradoxically, they also provide a habitat for intracellular bacterial survival. This paradoxical role of Mphi remains poorly understood. Here we report that this dual role may emanate from the functional plasticity of Mphi: Whereas Mphi-1 polarized in the presence of granulocyte-Mphi colony-stimulating factor

F. A. W. Verreck; T. de Boer; D. M. Langenberg; M. A. Hoeve; M. Kramer; E. Vaisberg; R. Kastelein; A. Kolk; R. M. W. de Waal; T. H. M. Ottenhoff

2004-01-01

75

Phenotypic Skewing of Macrophages In Vitro by Secreted Factors from Colorectal Cancer Cells  

PubMed Central

Macrophages are cells with many important functions in both innate and adaptive immune responses and have been shown to play a complex role in tumor progression since they harbour both tumor preventing (M1 macrophages) and tumor promoting (M2 macrophages) activities. In many human cancers, infiltrating macrophages have been associated with a poor patient prognosis, and therefore suggested to be mainly of an M2 phenotype. However, we and others have previously shown that increased macrophage density in colorectal cancer (CRC) instead is correlated with an improved prognosis. It is an intriguing question if the different roles played by macrophages in various cancers could be explained by variations in the balance between M1 and M2 macrophage attributes, driven by tumor- or organ-specific factors in the tumor microenvironment of individual cancers. Here, we utilized an in vitro cell culture system of macrophage differentiation to compare differences and similarities in the phenotype (morphology, antigen-presentation, migration, endocytosis, and expression of cytokine and chemokine genes) between M1/M2 and tumor activated macrophages (TAMs), that could explain the positive role of macrophages in CRC. We found that secreted factors from CRC cells induced TAMs of a “mixed” M1/M2 phenotype, which in turn could contribute to a “good inflammatory response”. This suggests that re-education of macrophages might allow for important therapeutic advances in the treatment of human cancer. PMID:24058644

Edin, Sofia; Wikberg, Maria L.; Rutegard, Jorgen; Oldenborg, Per-Arne; Palmqvist, Richard

2013-01-01

76

?? T Cell and Other Immune Cells Crosstalk in Cellular Immunity  

PubMed Central

?? T cells have been recognized as effectors with immunomodulatory functions in cellular immunity. These abilities enable them to interact with other immune cells, thus having the potential for treatment of various immune-mediated diseases with adoptive cell therapy. So far, the interactions between ?? T cell and other immune cells have not been well defined. Here we will discuss the interactivities among them and the perspective on ?? T cells for their use in immunotherapy could be imagined. The understanding of the crosstalk among the immune cells in immunopathology might be beneficial for the clinical application of ?? T cell. PMID:24741636

He, Ying; Wu, Kangni; Hu, Yongxian; Sheng, Lixia; Tie, Ruxiu; Wang, Binsheng; Huang, He

2014-01-01

77

Cytotoxicity of lambda-cyhalothrin on the macrophage cell line RAW 264.7  

Microsoft Academic Search

The wide use and wide-spectrum toxicity of synthetic pyrethroids (SPs) insecticides make them an emerging ecotoxicological concern. Some previous studies showed that SPs possessed cytotoxicity in some immune cells such as human lymphocytes and rat bone marrow. However, the cytotoxicity of SPs to macrophages, which are crucial to innate immunity, has not been explored. In the present report, we investigated

Quan Zhang; Cui Wang; Liwei Sun; Ling Li; Meirong Zhao

2010-01-01

78

Redirecting In vivo Elicited Tumor Infiltrating Macrophages and Dendritic Cells towards Tumor Rejection  

Microsoft Academic Search

A hostile tumor microenvironment interferes with the development and function of the adaptive immune response. Here we report the mechanisms by which large numbers of tumor-infiltrating macrophages and dendritic cells (DC) can be redirected to become potent effectors and activators of the innate and adaptive immunity, respectively. We use adenovi- ral delivery of the CCL16 chemokine to promote accumulation of

Cristiana Guiducci; Alain P. Vicari; Sabina Sangaletti; Giorgio Trinchieri; Mario P. Colombo

79

Cyclooxygenase-2 inhibition attenuates hypoxic cancer cells induced m2-polarization of macrophages.  

PubMed

Tumor associated macrophages (TAMs), represent a major subpopulation of tumor infiltrating immune cells. These alternatively activated M2—polarized macrophages are well known for their pro—tumor functions. Owing to their established role in potentiating tumor—neovasculogenesis and metastasis, TAMs have emerged as promising target for anti—cancer immunotherapy. One of the key TAMs related phenomenon that is amenable to therapeutic intervention is their phenotype switching into alternatively activated M2—polarized macrophages. Hindering macrophage polarization towards a pro—tumor M2 phenotype, or better still reprogramming the M2 like TAMs towards M1 subtype is being considered a beneficial anti—cancer strategy. Hypoxic tumor milieu has been proposed as one of the most plausible factor governing M2—polarization of macrophages. We recently demonstrated that hypoxic tumor cells imparted a pro—angiogenic M2 skewed phenotype to macrophages. Furthermore, sizeable body of data indicates for participation of cyclooxygenase—2 (COX—2) in macrophage polarization. Concordantly, inhibition of COX—2 is associated with impaired macrophage polarization. Prompted by this in the current study we decided to explore if inhibition of COX—2 activity via chemical inhibitors may prevent hypoxic cancer cell induced M2—polarization of macrophages. We observed that treatment with Flunixin meglumine, an established preferential inhibitor of COX—2 activity markedly inhibited hypoxic cancer cell induced of M2—polarization of macrophages thereby indicating for usage of COX—2 inhibition as possible anti—cancer treatment modality. PMID:25210855

Dubey, P; Shrivastava, R; Tripathi, C; Jain, N K; Tewari, B N; Lone, M-U-D; Baghel, K S; Kumar, V; Misra, S; Bhadauria, S; Bhatt, M L B

2014-01-01

80

Direct Effects of Activin A on the Activation of Mouse Macrophage RAW264.7 Cells  

PubMed Central

Macrophages play critical roles in innate immune and acquired immune via secreting pro-inflammatory mediators, phagocytosing microorganisms and presenting antigens. Activin A, a member of transforming growth factor ? (TGF-?) superfamily, is produced by macrophages and microglia cells. In this study, we reported a direct effect of activin A as a pro-inflammatory factor on mouse macrophage cell line RAW264.7 cells. Our data revealed that activin A could not only increase IL-1? and IL-6 production from RAW264.7 cells, but also promote pinocytic and phagocytic activities of RAW264.7 cells. In addition, activin A obviously up-regulated MHC II expression on the surface of RAW264.7 cells, whereas did not influence MHC I expression. Activin A also enhanced CD80 expression, which is a marker of activated macrophages, but did not influence RAW264.7 cell proliferation. These data suggest that activin A may regulate primary macrophage-mediated innate and acquired immune response via promoting the activation of rest macrophages. PMID:19403063

Ge, Jingyan; Wang, Yinan; Feng, Ye; Liu, Haiyan; Cui, Xueling; Chen, Fangfang; Tai, Guixiang; Liu, Zhonghui

2009-01-01

81

Effects of T-2 Toxin on Cytokine Production by Mice Peritoneal Macrophages and Lymph Node T-Cells  

Microsoft Academic Search

Background: T-2 toxin is a mycotoxin of type A trichothecenes produced by several fungal genera such as Fusarium species. Mycotoxins can affect both cell mediated and humoral immune compartments. Objective: The purpose of this study was to investi- gate the effect of T-2 toxin on cytokine production by mouse peritoneal macrophages and lymph node T cells. Methods: Mouse peritoneal macrophages

Kazem Ahmadi; Majid Riazipour

82

The endosomal proteome of macrophage and dendritic cells.  

PubMed

The essential roles of the endovacuolar system in health and disease call for the development of new tools allowing a better understanding of the complex molecular machinery involved in endocytic processes. We took advantage of the floating properties of small latex beads (sLB) on a discontinuous sucrose gradient to isolate highly purified endosomes following internalization of small latex beads in J774 macrophages and bone marrow-derived dendritic cells (DC). We particularly focused on the isolation of macrophages early endosomes and late endosomes/lysosomes (LE/LYS) as well as the isolation of LE/LYS from immature and lipopolysaccharide-activated (mature) DC. We subsequently performed a comparative analysis of their respective protein contents by MS. As expected, proteins already known to localize to the early endosomes were enriched in the earliest fraction of J774 endosomes, while proteins known to accumulate later in the process, such as hydrolases, were significantly enriched in the LE/LYS preparations. We next compared the LE/LYS protein contents of immature DC and mature DC, which are known to undergo massive reorganization leading to potent immune activation. The differences between the protein contents of endocytic organelles from macrophages and DC were underlined by focusing on previously poorly characterized biochemical pathways, which could have an unexpected but important role in the endosomal functions of these highly relevant immune cell types. PMID:21280226

Duclos, Sophie; Clavarino, Giovanna; Rousserie, Gilles; Goyette, Guillaume; Boulais, Jonathan; Camossetto, Voahirana; Gatti, Evelina; LaBoissière, Sylvie; Pierre, Philippe; Desjardins, Michel

2011-03-01

83

Human Uveal Melanoma Cells Produce Macrophage Migration-Inhibitory Factor to Prevent Lysis by NK Cells1  

Microsoft Academic Search

Human uveal melanoma arises in an immune privileged ocular environment in which both adaptive and innate immune effector mechanisms are suppressed. Uveal melanoma is the most common intraocular tumor in adults and is derived from tissues in the eye that produce macrophage migration-inhibitory factor (MIF), a cytokine that has recently been demonstrated to produce immediate inhibition of NK cell-mediated lytic

Amanda C. Repp; Elizabeth S. Mayhew; Sherine Apte; Jerry Y. Niederkorn

84

THE INTERACTION OF PARTICULATE HORSERADISH PEROXIDASE (HRP)-ANTI HRP IMMUNE COMPLEXES WITH MOUSE PERITONEAL MACROPHAGES IN VITRO  

PubMed Central

The uptake, distribution, and fate of particulate horseradish peroxidase (HRP)-anti HRP aggregates has been studied in homogeneous monolayers of mouse macrophages in vitro. Macrophages rapidly interiorize the immune complexes after binding to the cell surface. The rate of interiorization is maximal for complexes formed in a broad zone of 4-fold antibody excess to equivalence and corresponds to a rate of 10% of the administered load/106 cells per hour. This rate is 4000-fold greater than the uptake of soluble HRP. The binding and endocytosis of HRP-anti HRP by macrophages is mediated by the trypsin insensitive Fc receptor. Cytochemically, intracellular HRP is localized within membrane bound vacuoles. After uptake of HRP, the enzymatic activity is degraded exponentially with a half-life of 14–18 hr until enzyme is no longer detectable. This half-life is twice as long as that previously observed for soluble uncomplexed HRP and is related to the combination of HRP with anti-HRP rather than the absolute amounts of enzyme or antibody ingested. The half-life of HRP-125I was 30 hr. Exocytosis of cell associated enzyme or TCA precipitable counts was not detected, nor were persistent surface complexes demonstrable. The extensive capacity of macrophages to interiorize and destroy large amounts of antigen after the formation of antibody illustrates a role of this cell in the efferent limb of the immune response. PMID:4656704

Steinman, Ralph M.; Cohn, Zanvil A.

1972-01-01

85

Fractional factorial design to investigate stromal cell regulation of macrophage plasticity.  

PubMed

Understanding the regulatory networks which control specific macrophage phenotypes is essential in identifying novel targets to correct macrophage mediated clinical disorders, often accompanied by inflammatory events. Since mesenchymal stromal cells (MSCs) have been shown to play key roles in regulating immune functions predominantly via a large number of secreted products, we used a fractional factorial approach to streamline experimental evaluation of MSC mediated inflammatory macrophage regulation. Our macrophage reprogramming metrics, human bone marrow MSC attenuation of macrophage pro-inflammatory M1 TNF? secretion and simultaneous enhanced expression of the M2 macrophage marker, CD206, were used as analysis endpoints. Objective evaluation of a panel of MSC secreted mediators indicated that PGE2 alone was sufficient in facilitating macrophage reprogramming, while IL4 only provided partial reprogramming. Inhibiting stromal cell PGE2 secretion with Indomethacin, reversed the macrophage reprogramming effect. PGE2 reprogramming was mediated through the EP4 receptor and indirectly through the CREB signaling pathway as GSK3 specific inhibitors induced M1 macrophages to express CD206. This reprogramming pathway functioned independently from the M1 suppression pathway, as neither CREB nor GSK3 inhibition reversed PGE2 TNF-? secretion attenuation. In conclusion, fractional factorial experimental design identified stromal derived PGE2 as the factor most important in facilitating macrophage reprogramming, albeit via two unique pathways. Biotechnol. Bioeng. 2014;111: 2239-2251. © 2014 Wiley Periodicals, Inc. PMID:24891120

Barminko, Jeffrey A; Nativ, Nir I; Schloss, Rene; Yarmush, Martin L

2014-11-01

86

Brugia malayi Microfilariae Induce a Regulatory Monocyte/Macrophage Phenotype That Suppresses Innate and Adaptive Immune Responses  

PubMed Central

Background Monocytes and macrophages contribute to the dysfunction of immune responses in human filariasis. During patent infection monocytes encounter microfilariae in the blood, an event that occurs in asymptomatically infected filariasis patients that are immunologically hyporeactive. Aim To determine whether blood microfilariae directly act on blood monocytes and in vitro generated macrophages to induce a regulatory phenotype that interferes with innate and adaptive responses. Methodology and principal findings Monocytes and in vitro generated macrophages from filaria non-endemic normal donors were stimulated in vitro with Brugia malayi microfilarial (Mf) lysate. We could show that monocytes stimulated with Mf lysate develop a defined regulatory phenotype, characterised by expression of the immunoregulatory markers IL-10 and PD-L1. Significantly, this regulatory phenotype was recapitulated in monocytes from Wuchereria bancrofti asymptomatically infected patients but not patients with pathology or endemic normals. Monocytes from non-endemic donors stimulated with Mf lysate directly inhibited CD4+ T cell proliferation and cytokine production (IFN-?, IL-13 and IL-10). IFN-? responses were restored by neutralising IL-10 or PD-1. Furthermore, macrophages stimulated with Mf lysate expressed high levels of IL-10 and had suppressed phagocytic abilities. Finally Mf lysate applied during the differentiation of macrophages in vitro interfered with macrophage abilities to respond to subsequent LPS stimulation in a selective manner. Conclusions and significance Conclusively, our study demonstrates that Mf lysate stimulation of monocytes from healthy donors in vitro induces a regulatory phenotype, characterized by expression of PD-L1 and IL-10. This phenotype is directly reflected in monocytes from filarial patients with asymptomatic infection but not patients with pathology or endemic normals. We suggest that suppression of T cell functions typically seen in lymphatic filariasis is caused by microfilaria-modulated monocytes in an IL-10-dependent manner. Together with suppression of macrophage innate responses, this may contribute to the overall down-regulation of immune responses observed in asymptomatically infected patients. PMID:25275395

Venugopal, Gopinath; Rao, Gopala B.; Lucius, Richard; Srikantam, Aparna; Hartmann, Susanne

2014-01-01

87

Macrophage Cell Lines Use CD81 in Cell Growth Regulation  

PubMed Central

CD81 is an integral membrane protein belonging to the tetraspanin superfamily. It has two extracellular domains that interact with cell surface proteins and two intracellular tails that contribute to cellular processes. Although there are considerable data about how CD81 affects T- and B-cell function, not much is known about how it impacts macrophages. To address this, we established four cell lines from mouse bone marrow in the presence of macrophage colony stimulating factor and transfection with SV40 large T antigen. Two were CD81?/? (ASD1 and ASD2) and two were CD81+/? (2ASD1.10 and 2BSD1.10). Cells were Mac-2-, PU.1-, and c-fms-positive and all the cell lines were phagocytic indicating that they were macrophage-like. In mixtures of the two cell types in tissue culture, CD81?/? cells out competed CD81+/? cells with CD81-bearing cells being undetectable after 50 cell culture passages. Although cell divisions during log-phase growth were not significantly different between CD81+/? macrophage cells and CD81?/? macrophage cells, we found that CD81?/? macrophage cells reached a higher density at confluency than CD81+/? macrophage cells. CD81 transcript levels increased as cultures became confluent, but transcript levels of other tetraspanin-related molecules remained relatively constant. Transfection of CD81 into ASD1 (CD81?/?) cells reduced the density of confluent cultures of transformants compared to cells transfected with vector alone. These data suggest that CD81 potentially plays a role in macrophage cell line growth regulation. PMID:19184252

Mordica, Whitney J.; Woods, Keith M.; Clem, Rollie J.; Passarelli, A. Lorena; Chapes, Stephen K.

2013-01-01

88

Helical Carbon Nanotubes Enhance the Early Immune Response and Inhibit Macrophage-Mediated Phagocytosis of Pseudomonas aeruginosa  

PubMed Central

Aerosolized or aspirated manufactured carbon nanotubes have been shown to be cytotoxic, cause pulmonary lesions, and demonstrate immunomodulatory properties. CD-1 mice were used to assess pulmonary toxicity of helical carbon nanotubes (HCNTs) and alterations of the immune response to subsequent infection by Pseudomonas aeruginosa in mice. HCNTs provoked a mild inflammatory response following either a single exposure or 2X/week for three weeks (multiple exposures) but were not significantly toxic. Administering HCNTs 2X/week for three weeks resulted in pulmonary lesions including granulomas and goblet cell hyperplasia. Mice exposed to HCNTs and subsequently infected by P. aeruginosa demonstrated an enhanced inflammatory response to P. aeruginosa and phagocytosis by alveolar macrophages was inhibited. However, clearance of P. aeruginosa was not affected. HCNT exposed mice depleted of neutrophils were more effective in clearing P. aeruginosa compared to neutrophil-depleted control mice, accompanied by an influx of macrophages. Depletion of systemic macrophages resulted in slightly inhibited bacterial clearance by HCNT treated mice. Our data indicate that pulmonary exposure to HCNTs results in lesions similar to those caused by other nanotubes and pre-exposure to HCNTs inhibit alveolar macrophage phagocytosis of P. aeruginosa. However, clearance was not affected as exposure to HCNTs primed the immune system for an enhanced inflammatory response to pulmonary infection consisting of an influx of neutrophils and macrophages. PMID:24324555

Walling, Brent E.; Kuang, Zhizhou; Hao, Yonghua; Estrada, David; Wood, Joshua D.; Lian, Feifei; Miller, Lou Ann; Shah, Amish B.; Jeffries, Jayme L.; Haasch, Richard T.; Lyding, Joseph W.; Pop, Eric; Lau, Gee W.

2013-01-01

89

Effect of long-term continuous consumption of fermented milk containing probiotic bacteria on mucosal immunity and the activity of peritoneal macrophages  

Microsoft Academic Search

The effect of the long-term administration of commercial fermented milk containing probiotic bacteria in the mucosal immune response and peritoneal macrophages was analyzed. BALB\\/c mice were fed with fermented milk for 98 consecutive days. Small and large intestines were removed for histology; IgA, CD4, CD8 cells and cytokines-producing cells were counted. The influence on the immune cells associated with bronchus

A. de Moreno de LeBlanc; S. Chaves; E. Carmuega; R. Weill; J. Antóine; Gabriela Perdigón

2008-01-01

90

Interactions between neutrophils and macrophages promote macrophage killing of rat muscle cells in vitro  

NASA Technical Reports Server (NTRS)

Current evidence indicates that the physiological functions of inflammatory cells are highly sensitive to their microenvironment, which is partially determined by the inflammatory cells and their potential targets. In the present investigation, interactions between neutrophils, macrophages and muscle cells that may influence muscle cell death are examined. Findings show that in the absence of macrophages, neutrophils kill muscle cells in vitro by superoxide-dependent mechanisms, and that low concentrations of nitric oxide (NO) protect against neutrophil-mediated killing. In the absence of neutrophils, macrophages kill muscle cells through a NO-dependent mechanism, and the presence of target muscle cells causes a three-fold increase in NO production by macrophages, with no change in the concentration of inducible nitric oxide synthase. Muscle cells that are co-cultured with both neutrophils and macrophages in proportions that are observed in injured muscle show cytotoxicity through a NO-dependent, superoxide-independent mechanism. Furthermore, the concentration of myeloid cells that is necessary for muscle killing is greatly reduced in assays that use mixed myeloid cell populations, rather than uniform populations of neutrophils or macrophages. These findings collectively show that the magnitude and mechanism of muscle cell killing by myeloid cells are modified by interactions between muscle cells and neutrophils, between muscle cells and macrophages and between macrophages and neutrophils.

Nguyen, Hal X.; Tidball, James G.

2003-01-01

91

Two-Photon Intravital Imaging of Lungs during Anthrax Infection Reveals Long-Lasting Macrophage-Dendritic Cell Contacts  

E-print Network

to the draining lymph nodes and elicit the immune response in pulmonary anthrax. The intimate and long-last- ingTwo-Photon Intravital Imaging of Lungs during Anthrax Infection Reveals Long-Lasting Macrophage, the agent of anthrax. We show that after alveolar macrophages capture spores, CD11b-positive dendritic cells

Paris-Sud XI, Université de

92

Age-related alterations in innate immune receptor expression and ability of macrophages to respond to pathogen challenge in vitro  

PubMed Central

The impact of ageing in innate immunity is poorly understood. Studies in the mouse model have described altered innate immune functions in aged macrophages, although these were not generally linked to altered expression of receptors or regulatory molecules. Moreover, the influence of ageing in the expression of these molecules has not been systematically examined. We investigated age-dependent expression differences in selected Toll-like and other pattern-recognition receptors, receptors involved in inflammatory amplification, and in transmembrane and intracellular regulators of inflammatory signaling. Young and aged macrophages were examined under resting conditions or upon activation with Porphyromonas gingivalis, a major pathogen in periodontal disease, the prevalence and severity of which increase in old age. We detected a limited number of age-dependent alterations, involving both reduction and increase of immune activity. Interestingly, surface expression of receptors that amplify inflammation (C5a anaphylatoxin receptor and triggering receptor expressed on myeloid cells [TREM]-1) was elevated in aged macrophages. No significant age-dependent differences were observed regarding the phagocytosis and intracellular killing of P. gingivalis, consistent with lack of significant changes in phagocytic receptor expression and induction of antimicrobial molecules. Therefore, at least at the cellular level, certain aspects of innate immune function may not necessarily decline with age. PMID:19559723

Liang, Shuang; Domon, Hisanori; Hosur, Kavita B.; Wang, Min; Hajishengallis, George

2009-01-01

93

T Cell-Mediated Host Immune Defenses in the Lung  

PubMed Central

Evidence has increasingly shown that the lungs are a major site of immune regulation. A robust and highly regulated immune response in the lung protects the host from pathogen infection, whereas an inefficient or deleterious response can lead to various pulmonary diseases. Many cell types, such as epithelial cells, dendritic cells, macrophages, neutrophils, eosinophils, and B and T lymphocytes, contribute to lung immunity. This review focuses on the recent advances in understanding how T lymphocytes mediate pulmonary host defenses against bacterial, viral, and fungal pathogens. PMID:23516986

Chen, Kong; Kolls, Jay K.

2014-01-01

94

Denervated Schwann Cells Attract Macrophages by Secretion of Leukemia Inhibitory Factor (LIF) and Monocyte Chemoattractant Protein1 in a Process Regulated by Interleukin6 and LIF  

Microsoft Academic Search

Injury to peripheral nerves results in the infiltration of immune cells, which remove axonal- and myelin-derived material. Schwann cells could play a key role in this process by regulating macrophage infiltration. We show here that medium conditioned by primary denervated Schwann cells or the Schwannoma cell line RN22 produces chemotactic activity for macrophages. The pres- ence of blocking antibodies to

George K. Tofaris; Paul H. Patterson; Kristjan R. Jessen; Rhona Mirsky

2002-01-01

95

Teleost T and NK cell immunity.  

PubMed

The main function of the immune system is to maintain the organism's homeostasis when invaded by foreign material or organisms. Prior to successful elimination of the invader it is crucial to distinguish self from non-self. Most pathogens and altered cells can be recognized by immune cells through expressed pathogen- or danger-associated molecular patterns (PAMPS or DAMPS, respectively), through non-self (e.g. allogenic or xenogenic cells) or missing major histocompatibility (MHC) class I molecules (some virus-infected target cells), and by presenting foreign non-self peptides of intracellular (through MHC class I-e.g. virus-infected target cells) or extracellular (through MHC class II-e.g. from bacteria) origin. In order to eliminate invaders directly or by destroying their ability to replicate (e.g. virus-infected cells) specialized immune cells of the innate and adaptive responses appeared during evolution. The first line of defence is represented by the evolutionarily ancient macrophages and natural killer (NK) cells. These innate mechanisms are well developed in bony fish. Two types of NK cell homologues have been described in fish: non-specific cytotoxic cells and NK-like cells. Adaptive cell-mediated cytotoxicity (CMC) requires key molecules expressed on cytotoxic T lymphocytes (CTLs) and target cells. CTLs kill host cells harbouring intracellular pathogens by binding of their T cell receptor (TCR) and its co-receptor CD8 to a complex of MHC class I and bound peptide on the infected host cell. Alternatively, extracellular antigens are taken up by professional antigen presenting cells such as macrophages, dendritic cells and B cells to process those antigens and present the resulting peptides in association with MHC class II to CD4(+) T helper cells. During recent years, genes encoding MHC class I and II, TCR and its co-receptors CD8 and CD4 have been cloned in several fish species and antibodies have been developed to study protein expression in morphological and functional contexts. Functional assays for innate and adaptive lymphocyte responses have been developed in only a few fish species. This review summarizes and discusses recent results and developments in the field of T and NK cell responses with focus on economically important and experimental model fish species in the context of vaccination. PMID:23664867

Fischer, Uwe; Koppang, Erling Olaf; Nakanishi, Teruyuki

2013-08-01

96

The effects of ?-glucan on human immune and cancer cells  

PubMed Central

Non-prescriptional use of medicinal herbs among cancer patients is common around the world. The alleged anti-cancer effects of most herbal extracts are mainly based on studies derived from in vitro or in vivo animal experiments. The current information suggests that these herbal extracts exert their biological effect either through cytotoxic or immunomodulatory mechanisms. One of the active compounds responsible for the immune effects of herbal products is in the form of complex polysaccharides known as ?-glucans. ?-glucans are ubiquitously found in both bacterial or fungal cell walls and have been implicated in the initiation of anti-microbial immune response. Based on in vitro studies, ?-glucans act on several immune receptors including Dectin-1, complement receptor (CR3) and TLR-2/6 and trigger a group of immune cells including macrophages, neutrophils, monocytes, natural killer cells and dendritic cells. As a consequence, both innate and adaptive response can be modulated by ?-glucans and they can also enhance opsonic and non-opsonic phagocytosis. In animal studies, after oral administration, the specific backbone 1?3 linear ?-glycosidic chain of ?-glucans cannot be digested. Most ?-glucans enter the proximal small intestine and some are captured by the macrophages. They are internalized and fragmented within the cells, then transported by the macrophages to the marrow and endothelial reticular system. The small ?-glucans fragments are eventually released by the macrophages and taken up by other immune cells leading to various immune responses. However, ?-glucans of different sizes and branching patterns may have significantly variable immune potency. Careful selection of appropriate ?-glucans is essential if we wish to investigate the effects of ?-glucans clinically. So far, no good quality clinical trial data is available on assessing the effectiveness of purified ?-glucans among cancer patients. Future effort should direct at performing well-designed clinical trials to verify the actual clinical efficacy of ?-glucans or ?-glucans containing compounds. PMID:19515245

Chan, Godfrey Chi-Fung; Chan, Wing Keung; Sze, Daniel Man-Yuen

2009-01-01

97

Macrophages: supportive cells for tissue repair and regeneration Short title: Macrophages in tissue repair and regeneration  

E-print Network

1 Macrophages: supportive cells for tissue repair and regeneration Short title: Macrophages in tissue repair and regeneration Bénédicte Chazaud Institut Cochin, INSERM U1016, Paris, France; CNRS 8104 cells ­ Regeneration ­ Repair ­ Resolution of inflammation Abbreviations 2-acetylaminofluorene (2-AAF

Paris-Sud XI, Université de

98

Lymph node macrophages  

PubMed Central

Summary Lymph node (LN) macrophages have long been known for their efficient uptake of lymph-borne antigens. A convergence of studies on innate and adaptive immune responses has led to exciting recent advances in understanding their more specialized properties: presenting antigens to B cells, dendritic cells and T cells, producing trophic factors and cytokines, and, remarkably, being permissive for viral infection, a property critical for mounting anti-viral responses. LN macrophages have been traditionally divided into subsets based on their subcapsular sinus and medullary locations. Here we classify LN macrophages into three subsets: subcapsular sinus macrophages (SSMs), medullary sinus macrophages (MSMs) and medullary cord macrophages (MCMs). We review the literature regarding the roles of these cells in innate and adaptive immune responses and requirements for their development. We also discuss challenges associated with their purification as well as the existence of additional heterogeneity among LN macrophages. PMID:22488251

Gray, Elizabeth E.; Cyster, Jason G.

2013-01-01

99

New Lives Given by Cell Death: Macrophage Differentiation Following Their Encounter with Apoptotic Leukocytes during the Resolution of Inflammation  

PubMed Central

Monocytes that migrate into tissues during inflammatory episodes and differentiate to macrophages were previously classified as classically (M1) or alternatively (M2) activated macrophages, based on their exposure to different fate-determining mediators. These macrophage subsets display distinct molecular markers and differential functions. At the same time, studies from recent years found that the encounter of apoptotic leukocytes with macrophages leads to the clearance of this cellular “debris” by the macrophages, while concomitantly reprogramming/immune-silencing the macrophages. While some of the features of M2 differentiation, such as arginase-1 (murine) and 15-lipoxygenases (human and murine) expression, were also displayed by macrophages following the engulfment of apoptotic cells, it was not clear whether apoptotic cells can be regarded as an M2-like differentiating signal. In this manuscript we review the recent information regarding the impact of apoptotic cells on macrophage phenotype changes in molecular terms. We will focus on recent evidence for the in vivo existence of distinct pro-resolving macrophages and the role of apoptotic cells, specialized lipid mediators, and glucocorticoids in their generation. Consequently, we will suggest that these pro-resolving CD11blow macrophages have metamorphed from M2-like macrophages, and modulated their protein profile to accommodate the changes in their function. PMID:22566890

Ariel, Amiram; Serhan, Charles N.

2012-01-01

100

NLRX1 prevents mitochondrial induced apoptosis and enhances macrophage antiviral immunity by interacting with influenza virus PB1-F2 protein  

PubMed Central

To subvert host immunity, influenza A virus (IAV) induces early apoptosis in innate immune cells by disrupting mitochondria membrane potential via its polymerase basic protein 1-frame 2 (PB1-F2) accessory protein. Whether immune cells have mechanisms to counteract PB1-F2–mediated apoptosis is currently unknown. Herein, we define that the host mitochondrial protein nucleotide-binding oligomerization domain-like receptor (NLR)X1 binds to viral protein PB1-F2, preventing IAV-induced macrophage apoptosis and promoting both macrophage survival and type I IFN signaling. We initially observed that Nlrx1-deficient mice infected with IAV exhibited increased pulmonary viral replication, as well as enhanced inflammatory-associated pulmonary dysfunction and morbidity. Analysis of the lungs of IAV-infected mice revealed markedly enhanced leukocyte recruitment but impaired production of type I IFN in Nlrx1?/? mice. Impaired type I IFN production and enhanced viral replication was recapitulated in Nlrx1?/? macrophages and was associated with increased mitochondrial mediated apoptosis. Through gain- and loss-of-function strategies for protein interaction, we identified that NLRX1 directly bound PB1-F2 in the mitochondria of macrophages. Using a recombinant virus lacking PB1-F2, we confirmed that deletion of PB1-F2 abrogated NLRX1-dependent macrophage type I IFN production and apoptosis. Thus, our results demonstrate that NLRX1 acts as a mitochondrial sentinel protecting macrophages from PB1-F2–induced apoptosis and preserving their antiviral function. We further propose that NLRX1 is critical for macrophage immunity against IAV infection by sensing the extent of viral replication and maintaining a protective balance between antiviral immunity and excessive inflammation within the lungs. PMID:24799673

Jaworska, Joanna; Coulombe, François; Downey, Jeffrey; Tzelepis, Fanny; Shalaby, Karim; Tattoli, Ivan; Berube, Julie; Rousseau, Simon; Martin, James G.; Girardin, Stephen E.; McCullers, Jonathan A.; Divangahi, Maziar

2014-01-01

101

Decreased circulating macrophage migration inhibitory factor (MIF) protein and blood mononuclear cell MIF transcripts in children with Plasmodium falciparum malaria  

Microsoft Academic Search

Plasmodium falciparum malaria remains one of the most frequently lethal diseases affecting children in sub-Saharan Africa, yet the immune mediators that regulate pathogenesis are only partially defined. Since macrophage migration inhibitory factor (MIF) is important for regulating innate immunity in bacterial and parasitic infections, circulating MIF and peripheral blood mononuclear cell (PBMC) MIF transcripts were investigated in children with acute

Gordon A. Awandare; James B. Hittner; Peter G. Kremsner; Daniel O. Ochiel; Christopher C. Keller; J. Brice Weinberg; Ian A. Clark; Douglas J. Perkins

2006-01-01

102

The Macrophage Migration Inhibitory Factor-Glucocorticoid Dyad: Regulation of Inflammation and Immunity  

Microsoft Academic Search

The cytokine macrophage migration inhibitory factor (MIF) occupies a unique position in phys- iology by its ability to directly regulate the immu- nosuppressive actions of glucocorticoids. We re- view herein the interactions between MIF and glucocorticoids within the immune system and discuss the relevance of the MIF-glucocorticoid regulatory dyad in physiology and immunopa- thology. Therapeutic antagonism of MIF may be

Harry Flaster; Jurgen Bernhagen; Thierry Calandra; Richard Bucala

2007-01-01

103

Improved Method for Culturing Guinea-Pig Macrophage Cells  

NASA Technical Reports Server (NTRS)

Proper nutrients and periodic changes in culture medium maintain cell viability for a longer period. New method uses a thioglycolate solution, instead of mineral oil, to induce macrophage cells in guinea pigs and also uses an increased percent of fetal-calf bovine serum in cultivation medium. Macrophage cells play significant roles in the body's healing and defense systems.

Savage, J.

1982-01-01

104

A novel biofuel cell harvesting energy from activated human macrophages  

Microsoft Academic Search

Macrophage phagocytosis activates NADPH oxidase, an electron transport system in the plasma membrane. This study examined the feasibility of utilizing electrons transferred through the plasma membrane via NADPH oxidase to run a biofuel cell. THP-1 human monocytic cells were chemically stimulated to differentiate into macrophages. Further they were activated to induce a phagocytic response. During differentiation, cells became adherent to

Miho Sakai; Andreas Vonderheit; Xun Wei; Claudia Küttel; Andreas Stemmer

2009-01-01

105

NKT cells in mucosal immunity  

Microsoft Academic Search

The gastrointestinal tract allows the residence of an almost enumerable number of bacteria. To maintain homeostasis, the mucosal immune system must remain tolerant to the commensal microbiota and eradicate pathogenic bacteria. Aberrant interactions between the mucosal immune cells and the microbiota have been implicated in the pathogenesis of inflammatory disorders, such as inflammatory bowel disease (IBD). In this review, we

S Middendorp; E E S Nieuwenhuis; EES Nieuwenhuis

2009-01-01

106

Cell-Mediated Immunity in the Lungs of Rabbits Using Conjugated Proteins  

Microsoft Academic Search

A study using direct macrophage migration inhibition of cells from the lower respiratory tract of rabbits immunized with conjugated proteins, incorporated into a killed BCG-oil emulsion, revealed that the reaction was largely carrier specific. The only exception was when bronchoalveolar cells (BAC) from animals immunized with dinitrophenol coupled to ovalbumin (DNP-OA) were significantly immobilized with DNP coupled to bovine ?-globulin

V. L. Moore; L. L. Johnson; J. O. Stevens

1978-01-01

107

Modulators affecting the immune dialogue between human immune and colon cancer cells.  

PubMed

The link between chronic inflammation and colorectal cancer has been well established. The events proceeding along tumorigenesis are complicated and involve cells activated at the cancer microenvironment, tumor infiltrating polymorphonuclears, immune cells including lymphocyte subtypes and peripheral blood mononuclear cells (PBMC), as well as tumor-associated macrophages. The immune cells generate inflammatory cytokines, several of them playing a crucial role in tumorigenesis. Additional factors, such as gene expression regulated by cytokines, assembling of tumor growth- and transforming factors, accelerated angiogenesis, delayed apoptosis, contribute all to initiation, development and migration of tumor cells. Oxygen radical species originating from the inflammatory area promote cell mutation and cancer proliferation. Tumor cells may over-express pro-inflammatory mediators that in turn activate immune cells for inflammatory cytokines production. Consequently, an immune dialogue emerges between immune and cancer cells orchestrated through a number of activated molecular pathways. Cytokines, encompassing migration inhibitory factor, transforming growth factor beta 1, tumor necrosis factor-?, Interleukin (IL)-6, IL-10, IL-12, IL-17, IL-23 have been reported to be involved in human cancer development. Some cytokines, namely IL-5, IL-6, IL-10, IL-22 and growth factors promote tumor development and metastasis, and inhibit apoptosis via activation of signal transducer activator transcription-3 transcription factor. Colon cancer environment comprises mesenchymal, endothelial and immune cells. Assessment of the interaction between components in the tumor environment and malignant cells requires a reconsideration of a few topics elucidating the role of chronic inflammation in carcinogenesis, the function of the immune cells expressed by inflammatory cytokine production, the immunomodulation of cancer cells and the existence of a cross-talk between immune and malignant cells leading to a balance in cytokine production. It is conceivable that the prevalence of anti-inflammatory cytokine production by PBMC in the affected colonic mucosa will contribute to the delay, or even to halt down malignant expansion. Targeting the interplay between immune and cancer cells by mediators capable to alter cytokine secretion toward increased anti-inflammatory cytokine release by PBMC and tumor associated macrophages, may serve as an additional strategy for treatment of malignant diseases. This review will focus on the inflammatory events preceding tumorigenesis in general, and on a number of modulators capable to affect colon cancer cell-induced production of inflammatory cytokines by PBMC through alteration of the immune cross-talk between PBMC and cancer cells. PMID:24834143

Djaldetti, Meir; Bessler, Hanna

2014-05-15

108

Proportion of infiltrating IgG-binding immune cells predict for tumour hypoxia  

PubMed Central

Macrophages can account for up to 50% of tumour mass and secrete many angiogenic factors. Furthermore, tumour hypoxia is thought to play a major role in the activation of macrophages and the regulation of angiogenesis. In this paper, we demonstrate a strong correlation between hypoxia and the recruitment of immune cells binding to IgG in 8 experimental tumours. We provide evidence that IgG binding immune cells in 3 tumour lines are predominately composed of macrophages. Reduced oxygenation may act as a stimulus for recruitment of immune cells to the tumour mass, and the detection of either IgG-positive host cells or macrophages may offer an alternative method for monitoring tumour hypoxia. © 2001 Cancer Research Campaign http://www.bjcancer.com PMID:11237382

Collingridge, D R; Hill, S A; Chaplin, D J

2001-01-01

109

Genome-wide innate immune responses in HIV-1-infected macrophages are preserved despite attenuation of the NF-kappa B activation pathway.  

PubMed

Macrophages contribute to HIV-1 infection at many levels. They provide permissive cells at the site of inoculation, augment virus transfer to T cells, generate long-lived viral reservoirs, and cause bystander cell apoptosis. A body of evidence suggests that the role of macrophages in cellular host defense is also compromised by HIV-1 infection. In this respect, macrophages are potent cells of the innate immune system that initiate and regulate wide-ranging immunological responses. This study focuses on the effect of HIV-1 infection on innate immune responses by macrophages at the level of signal transduction, whole genome transcriptional profiling, and cytokine secretion. We show that in an ex vivo model, M-CSF-differentiated monocyte-derived macrophages uniformly infected with replicating CCR5-tropic HIV-1, without cytopathic effect, exhibit selective attenuation of the NF-kappaB activation pathway in response to TLR4 and TLR2 stimulation. However, functional annotation clustering analysis of genome-wide transcriptional responses to LPS stimulation suggests substantial preservation of gene expression changes at the systems level, with modest attenuation of a subset of up-regulated LPS-responsive genes, and no effect on a selection of inflammatory cytokine responses at the protein level. These results extend existing reports of inhibitory interactions between HIV-1 accessory proteins and NF-kappaB signaling pathways, and whole genome expression profiling provides comprehensive assessment of the consequent effects on immune response gene expression. Unexpectedly, our data suggest innate immune responses are broadly preserved with limited exceptions, and pave the way for further study of the complex relationship between HIV-1 and immunological pathways within macrophages. PMID:19109163

Noursadeghi, Mahdad; Tsang, Jhen; Miller, Robert F; Straschewski, Sarah; Kellam, Paul; Chain, Benjamin M; Katz, David R

2009-01-01

110

Antagonism by Ganoderma lucidum polysaccharides against the suppression by culture supernatants of B16F10 melanoma cells on macrophage.  

PubMed

It is well-documented that macrophages have the functions to regulate antitumor immune response. Antitumor response can be launched by a series of events, starting with inflammation mediated by monocyte/macrophages, which stimulates natural killer and dendritic cells and finally activates the cytotoxic lymphoid system. Monocytes/macrophages may be the first line of defense in tumors. However, specific and nonspecific immunotherapy for human cancer has shown no success or limited success in clinical trials. Part of the reasons attribute to tumor-derived soluble factors that suppress functions of immune cells or induce apoptosis of these cells, including macrophages. Therefore, antagonism of the suppression on the macrophages is an important goal for tumor immunotherapy. To achieve this purpose, Ganoderma lucidum polysaccharides (Gl-PS) with multiple bioactivities were used on mouse peritoneal macrophages incubating with culture supernatants of B16F10 melanoma cells (B16F10-CS). It was shown that the viability, phagocytic activity, NO production, TNF-? production and activity in peritoneal macrophages after activation by lipopolysaccharide were suppressed by B16F10-CS, while the suppressions were fully or partially antagonized by Gl-PS. In conclusion, B16F10-CS is suppressive to the viability, phagocytic activity, NO production, TNF-? production and activity in peritoneal macrophages while Gl-PS had the antagonistic effects against this suppression, suggesting this potential of Gl-PS to facilitate cancer immunotherapy. PMID:23519930

Lu, Jie; Sun, Li-Xin; Lin, Zhi-Bin; Duan, Xin-Suo; Ge, Zhi-Hua; Xing, En-Hong; Lan, Tian-Fei; Yang, Ning; Li, Xue-Jun; Li, Min; Li, Wei-Dong

2014-02-01

111

Marginal zone CD169+ macrophages coordinate apoptotic cell-driven cellular recruitment and tolerance  

PubMed Central

Tolerance to apoptotic cells is essential to prevent inflammatory pathology. Though innate responses are critical for immune suppression, our understanding of early innate immunity driven by apoptosis is lacking. Herein we report apoptotic cells induce expression of the chemokine CCL22 in splenic metallophillic macrophages, which is critical for tolerance. Systemic challenge with apoptotic cells induced rapid production of CCL22 in CD169+ (metallophillic) macrophages, resulting in accumulation and activation of FoxP3+ Tregs and CD11c+ dendritic cells, an effect that could be inhibited by antagonizing CCL22-driven chemotaxis. This mechanism was essential for suppression after apoptotic cell challenge, because neutralizing CCL22 or its receptor, reducing Treg numbers, or blocking effector mechanisms abrogated splenic TGF-? and IL-10 induction; this promoted a shift to proinflammatory cytokines associated with a failure to suppress T cells. Similarly, CCR4 inhibition blocked long-term, apoptotic cell-induced tolerance to allografts. Finally, CCR4 inhibition resulted in a systemic breakdown of tolerance to self after apoptotic cell injection with rapid increases in anti-dsDNA IgG and immune complex deposition. Thus, the data demonstrate CCL22-dependent chemotaxis is a key early innate response required for apoptotic cell-induced suppression, implicating a previously unknown mechanism of macrophage-dependent coordination of early events leading to stable tolerance. PMID:24591636

Ravishankar, Buvana; Shinde, Rahul; Liu, Haiyun; Chaudhary, Kapil; Bradley, Jillian; Lemos, Henrique P.; Chandler, Phillip; Tanaka, Masato; Munn, David H.; Mellor, Andrew L.; McGaha, Tracy L.

2014-01-01

112

TIM-4, expressed by medullary macrophages, regulates respiratory tolerance by mediating phagocytosis of antigen-specific T cells  

PubMed Central

Respiratory exposure to antigen induces T cell tolerance via several overlapping mechanisms that limit the immune response. While the mechanisms involved in the development of Treg cells have received much attention, those that result in T cell deletion are largely unknown. Herein, we show that F4/80+ lymph node medullary macrophages expressing TIM-4, a phosphatidylserine receptor, remove antigen-specific T cells during respiratory tolerance, thereby reducing secondary T cell responses. Blockade of TIM-4 inhibited the phagocytosis of antigen-specific T cells by TIM-4 expressing lymph node medullary macrophages, resulting in an increase in the number of antigen-specific T cells and the abrogation of respiratory tolerance. Moreover, specific depletion of medullary macrophages inhibited the induction of respiratory tolerance, highlighting the key role of TIM-4 and medullary macrophages in tolerance. Therefore, TIM-4-mediated clearance of antigen specific T cells represents an important previously unrecognized mechanism regulating respiratory tolerance. PMID:23149665

Albacker, Lee A; Yu, Sanhong; Bedoret, Denis; Lee, Wan-Ling; Umetsu, Sarah E; Monahan, Sheena; Freeman, Gordon J; Umetsu, Dale T; DeKruyff, Rosemarie H

2014-01-01

113

The innate and adaptive immune response induced by alveolar macrophages exposed to ambient particulate matter  

SciTech Connect

Emerging epidemiological evidence suggests that exposure to particulate matter (PM) air pollution increases the risk of cardiovascular events but the exact mechanism by which PM has adverse effects is still unclear. Alveolar macrophages (AM) play a major role in clearing and processing inhaled PM. This comprehensive review of research findings on immunological interactions between AM and PM provides potential pathophysiological pathways that interconnect PM exposure with adverse cardiovascular effects. Coarse particles (10 {mu}m or less, PM{sub 10}) induce innate immune responses via endotoxin-toll-like receptor (TLR) 4 pathway while fine (2.5 {mu}m or less, PM{sub 2.5}) and ultrafine particles (0.1 {mu}m or less, UFP) induce via reactive oxygen species generation by transition metals and/or polyaromatic hydrocarbons. The innate immune responses are characterized by activation of transcription factors [nuclear factor (NF)-{kappa}B and activator protein-1] and the downstream proinflammatory cytokine [interleukin (IL)-1{beta}, IL-6, and tumor necrosis factor-{alpha}] production. In addition to the conventional opsonin-dependent phagocytosis by AM, PM can also be endocytosed by an opsonin-independent pathway via scavenger receptors. Activation of scavenger receptors negatively regulates the TLR4-NF-{kappa}B pathway. Internalized particles are subsequently subjected to adaptive immunity involving major histocompatibility complex class II (MHC II) expression, recruitment of costimulatory molecules, and the modulation of the T helper (Th) responses. AM show atypical antigen presenting cell maturation in which phagocytic activity decreases while both MHC II and costimulatory molecules remain unaltered. PM drives AM towards a Th1 profile but secondary responses in a Th1- or Th-2 up-regulated milieu drive the response in favor of a Th2 profile.

Miyata, Ryohei; Eeden, Stephan F. van, E-mail: Stephan.vanEeden@hli.ubc.ca

2011-12-15

114

Sessile alveolar macrophages communicate with alveolar epithelium to modulate immunity.  

PubMed

The tissue-resident macrophages of barrier organs constitute the first line of defence against pathogens at the systemic interface with the ambient environment. In the lung, resident alveolar macrophages (AMs) provide a sentinel function against inhaled pathogens. Bacterial constituents ligate Toll-like receptors (TLRs) on AMs, causing AMs to secrete proinflammatory cytokines that activate alveolar epithelial receptors, leading to recruitment of neutrophils that engulf pathogens. Because the AM-induced response could itself cause tissue injury, it is unclear how AMs modulate the response to prevent injury. Here, using real-time alveolar imaging in situ, we show that a subset of AMs attached to the alveolar wall form connexin 43 (Cx43)-containing gap junction channels with the epithelium. During lipopolysaccharide-induced inflammation, the AMs remained sessile and attached to the alveoli, and they established intercommunication through synchronized Ca(2+) waves, using the epithelium as the conducting pathway. The intercommunication was immunosuppressive, involving Ca(2+)-dependent activation of Akt, because AM-specific knockout of Cx43 enhanced alveolar neutrophil recruitment and secretion of proinflammatory cytokines in the bronchoalveolar lavage. A picture emerges of a novel immunomodulatory process in which a subset of alveolus-attached AMs intercommunicates immunosuppressive signals to reduce endotoxin-induced lung inflammation. PMID:24463523

Westphalen, Kristin; Gusarova, Galina A; Islam, Mohammad N; Subramanian, Manikandan; Cohen, Taylor S; Prince, Alice S; Bhattacharya, Jahar

2014-02-27

115

Fc Gamma Receptor IIb on GM-CSF Macrophages Controls Immune Complex Mediated Inhibition of Inflammatory Signals  

PubMed Central

Background In rheumatoid arthritis (RA) macrophages play a major role in amplifying synovial inflammation. Important activating signals are those induced by Toll-like receptor (TLR) ligands and by activated T cells. The balance between activating and inhibitory Fc gamma receptors (Fc?Rs) on macrophages might be crucial in modulating these inflammatory responses. The purpose of this study was to determine Fc?R expression on pro- and anti-inflammatory macrophages (gmM? and mM?, respectively) and identify functional consequences on immune complex uptake and macrophage activation. Methods Human monocytes were isolated and differentiated into gmM? and mM?. A full Fc?R characterization of both macrophage subtypes was performed and uptake of fluorescent immune complexes (ICs) was determined. Fc?RIIb isoforms were determined by qPCR. Macrophages were stimulated via different TLRs or cytokine activated T cells in the presence or absence of ICs and cytokine production was determined. Blocking studies were performed to look into the pathways involved. Results mM? expressed high levels of the activating Fc?RIIa and Fc?RIII and low levels of the inhibitory Fc?RIIb, while the Fc?R balance on gmM? was shifted towards the inhibitory Fc?RIIb. This was accompanied by a clear increase in Fc?RIIb1 mRNA expression in gmM?. This resulted in higher IC uptake by mM? compared to gmM?. Furthermore, Fc?R-mediated stimulation of gmM? inhibited TLR2, 3, 4 and 7/8 mediated cytokine production via Fc?RIIb and PI3K signaling. In addition, gmM? but not mM? produced TNF? upon co-culture with cytokine activated T cells, which was reduced by IC binding to Fc?RIIb. The latter was dependent on PI3K signaling and COX2. Conclusions Fc?R expression patterns on gmM? and mM? are significantly different, which translates in clear functional differences further substantiating Fc?RIIb as an interesting target for inflammation control in RA and other autoimmune/inflammatory diseases. PMID:25340460

Santegoets, Kim C. M.; Wenink, Mark H.; van den Berg, Wim B.; Radstake, Timothy R. D. J.

2014-01-01

116

PRODUCTION OF MACROPHAGE MIGRATION INHIBITION FACTOR BY CONTINUOUS CELL LINES  

PubMed Central

Macrophage migration inhibitory factor (MIF) was found in media of human and mouse lymphocyte and fibroblast cell lines that were continuously growing. Its release was dependent on activation of the cells to enter the mitotic cycle, particularly on cells in S phase. The greatest quantity of MIF was detected in supernatants of lymphocytes collected during S phase after the cells were synchronized in G1 and in supernatants of growing fibroblasts. When the latter were contact inhibited little or no MIF was found in media. MIF was also released into media of cells proliferating in homologous serum in the absence of fetal calf serum and into media lacking any protein. The MIF produced by lymphocyte lines eluted from Sephadex G-100 in the same fashion as MIF produced by the interaction of sensitized guinea pig cells and antigen. The results indicated that MIF is not a specific mediator of delayed hypersensitivity and cellular immunity and that MIF released by sensitized lymphocytes incubated with antigen merely reflects that fraction of cells activated by antigen to enter the mitotic cycle. PMID:5060291

Tubergen, David G.; Feldman, Joseph D.; Pollock, E. M.; Lerner, Richard A.

1972-01-01

117

Enhancing effect of radioresistant spleen cells on the primary immune response against sheep RBC by mouse spleen cells in vitro.  

PubMed

Irradiated spleen cells cultured for 3 days, caused a stimulation of the primary in vitro immune response by normal spleen cells. These irradiated spleen cells were fractionated by velocity sedimentation and the fractions were tested for their stimulating activity. Only the macrophage enriched fractions were found to cause stimulation. The macrophages in these fractions were stuffed with erythrocytes and dead cells. The fractions enriched in thymus derived cells, had no effect on the immune response. Irradiated spleen cells cultured for 24 hours caused inhibition. It has not yet been determined whether this inhibition was due to some transient change in the macrophage population during incubation. The stimulating effect by the irradiated spleen cells from SPF mice was strongly reduced, which at least partly could be ascribed to the naturally occurring low number of macrophages in the spleens of these mice. PMID:1266673

Lubbe, F H; Zaalberg, O B

1976-01-01

118

Peritoneal catheter implantation elicits IL-10-producing immune-suppressor macrophages through a MyD88-dependent pathway.  

PubMed

Catheters are implanted into the peritoneal cavity during the process of peritoneal dialysis. Though these catheters may be effective and beneficial, the impact of catheters on the immune system is poorly understood. Catheters and other devices implanted in the peritoneal cavity elicit a foreign body reaction. However, the immunological consequences of this remain uncharacterized. To model this, catheters were implanted into the peritoneal cavity of healthy mice. Catheter implantation induced rapid cellular changes within the peritoneal cavity. Whereas B-cells and T-cells were reduced, catheter implantation was associated with the rapid expansion of F4/80-low-positive, CD11b-positive macrophages that elaborated IL-10, and suppressed T-cell division and Th1 skewing in co-culture assays. Peritoneal catheter elicited macrophages had increased Jmjd3 but reduced NF-?B activation, and their emergence was MyD88-dependent. Collectively, these studies indicate that foreign body implantation into the peritoneal cavity is associated with the expansion of suppressor macrophages. Whether peritoneal cavity catheter implantation may have systemic immunoregulatory roles remains to be explored. PMID:22341910

Min, So-Youn; Fu, Yuyang; Hutcheson, Jack; Wu, Tianfu; Khobahy, Elhaum; Zhu, Jiankun; Vanarsa, Kamala; Du, Yong; Park, Min-Jung; Park, Hyun-Sil; Saxena, Ramesh; Kim, Ho-Youn; Mohan, Chandra

2012-04-01

119

Macrophage cell lines use CD81 in cell growth regulation  

Microsoft Academic Search

CD81 is an integral membrane protein belonging to the tetraspanin superfamily. It has two extracellular domains that interact\\u000a with cell surface proteins and two intracellular tails that contribute to cellular processes. Although there are considerable\\u000a data about how CD81 affects T- and B-cell function, not much is known about how it impacts macrophages. To address this, we\\u000a established four cell

Whitney J. Mordica; Keith M. Woods; Rollie J. Clem; A. Lorena Passarelli; Stephen K. Chapes

2009-01-01

120

MMP28 promotes macrophage polarization toward M2 cells and augments pulmonary fibrosis.  

PubMed

Members of the MMP family function in various processes of innate immunity, particularly in controlling important steps in leukocyte trafficking and activation. MMP28 (epilysin) is a member of this family of proteinases, and we have found that MMP28 is expressed by macrophages and regulates their recruitment to the lung. We hypothesized that MMP28 regulates other key macrophage responses, such as macrophage polarization. Furthermore, we hypothesized that these MMP28-dependent changes in macrophage polarization would alter fibrotic responses in the lung. We examined the gene expression changes in WT and Mmp28-/- BMDMs, stimulated with LPS or IL-4/IL-13 to promote M1 and M2 cells, respectively. We also collected macrophages from the lungs of Pseudomonas aeruginosa-exposed WT and Mmp28-/- mice to evaluate changes in macrophage polarization. Lastly, we evaluated the macrophage polarization phenotypes during bleomycin-induced pulmonary fibrosis in WT and Mmp28-/- mice and assessed mice for differences in weight loss and total collagen levels. We found that MMP28 dampens proinflammatory macrophage function and promots M2 programming. In both in vivo models, we found deficits in M2 polarization in Mmp28-/- mice. In bleomycin-induced lung injury, these changes were associated with reduced fibrosis. MMP28 is an important regulator of macrophage polarization, promoting M2 function. Loss of MMP28 results in reduced M2 polarization and protection from bleomycin-induced fibrosis. These findings highlight a novel role for MMP28 in macrophage biology and pulmonary disease. PMID:23964118

Gharib, Sina A; Johnston, Laura K; Huizar, Isham; Birkland, Timothy P; Hanson, Josiah; Wang, Ying; Parks, William C; Manicone, Anne M

2014-01-01

121

Norcantharidin facilitates LPS-mediated immune responses by up-regulation of AKT/NF-?B signaling in macrophages.  

PubMed

Norcantharidin (NCTD), a demethylated analog of cantharidin, is a common used clinical drug to inhibit proliferation and metastasis of cancer cells. But the role of NCTD in modulating immune responses remains unknown. Here, we investigated the function and mechanism of NCTD in regulation of TLR4 associated immune response in macrophages. We evaluated the influence of NCTD on host defense against invaded pathogens by acute peritonitis mouse model, ELISA, Q-PCR, nitrite quantification, phagocytosis assay and gelatin zymography assay. Our data showed that the survival and the serum concentrations of IL-6 and TNF-? were all enhanced by NCTD significantly in peritonitis mouse model. Accordingly, LPS-induced cytokine, nitric oxide and MMP-9 production as well as the phagocytosis of bacteria were all up-regulated by NCTD in a dose dependent manner in both RAW264.7 cells and bone marrow-derived macrophages (BMMs). Then we further analyzed TLR4 associated signaling pathway by Western blot, Immunofluorescence and EMSA in the presence or absence of LPS. The phosphorylation of AKT and p65 at serine 536 but not serine 468 was enhanced obviously by NCTD in a dose dependent manner, whereas the degradation of I?B? was little effected. Consequently, the nuclear translocation and DNA binding ability of NF-?B was also increased by NCTD obviously in RAW264.7 cells. Our results demonstrated that NCTD could facilitate LPS-mediated immune response through promoting the phosphorylation of AKT/p65 and transcriptional activity of NF-?B, thus reprofiling the traditional anti-tumor drug NCTD as a novel immune regulator in promoting host defense against bacterial infection. PMID:22984593

Zhao, Qufei; Qian, Yu; Li, Ruimei; Tan, Binghe; Han, Honghui; Liu, Mingyao; Qian, Min; Du, Bing

2012-01-01

122

Norcantharidin Facilitates LPS-Mediated Immune Responses by Up-Regulation of AKT/NF-?B Signaling in Macrophages  

PubMed Central

Norcantharidin (NCTD), a demethylated analog of cantharidin, is a common used clinical drug to inhibit proliferation and metastasis of cancer cells. But the role of NCTD in modulating immune responses remains unknown. Here, we investigated the function and mechanism of NCTD in regulation of TLR4 associated immune response in macrophages. We evaluated the influence of NCTD on host defense against invaded pathogens by acute peritonitis mouse model, ELISA, Q-PCR, nitrite quantification, phagocytosis assay and gelatin zymography assay. Our data showed that the survival and the serum concentrations of IL-6 and TNF-? were all enhanced by NCTD significantly in peritonitis mouse model. Accordingly, LPS-induced cytokine, nitric oxide and MMP-9 production as well as the phagocytosis of bacteria were all up-regulated by NCTD in a dose dependent manner in both RAW264.7 cells and bone marrow-derived macrophages (BMMs). Then we further analyzed TLR4 associated signaling pathway by Western blot, Immunofluorescence and EMSA in the presence or absence of LPS. The phosphorylation of AKT and p65 at serine 536 but not serine 468 was enhanced obviously by NCTD in a dose dependent manner, whereas the degradation of I?B? was little effected. Consequently, the nuclear translocation and DNA binding ability of NF-?B was also increased by NCTD obviously in RAW264.7 cells. Our results demonstrated that NCTD could facilitate LPS-mediated immune response through promoting the phosphorylation of AKT/p65 and transcriptional activity of NF-?B, thus reprofiling the traditional anti-tumor drug NCTD as a novel immune regulator in promoting host defense against bacterial infection. PMID:22984593

Li, Ruimei; Tan, Binghe; Han, Honghui; Liu, Mingyao; Qian, Min; Du, Bing

2012-01-01

123

Pluripotent Stem Cells: Immune to the Immune system?  

PubMed Central

SUMMARY Embryonic stem cells (ESC) which were initially characterized as immune privileged subsequently have proven susceptible to immune recognition. Induced pluripotent stem cells (iPSCs) have been proposed as an autologous source of pluripotent cells; however, more recent data now suggest that even autologous iPSCs may be targets of immune rejection. With numerous clinical trials on the horizon, it is imperative that the immunology of pluripotent stem cells (PSCs) be definitively understood. PMID:23241742

Pearl, Jeremy I.; Kean, Leslie S.; Davis, Mark M.; Wu, Joseph C.

2013-01-01

124

Human Dermal CD14+ Cells Are a Transient Population of Monocyte-Derived Macrophages  

PubMed Central

Summary Dendritic cells (DCs), monocytes, and macrophages are leukocytes with critical roles in immunity and tolerance. The DC network is evolutionarily conserved; the homologs of human tissue CD141hiXCR1+CLEC9A+ DCs and CD1c+ DCs are murine CD103+ DCs and CD64?CD11b+ DCs. In addition, human tissues also contain CD14+ cells, currently designated as DCs, with an as-yet unknown murine counterpart. Here we have demonstrated that human dermal CD14+ cells are a tissue-resident population of monocyte-derived macrophages with a short half-life of <6 days. The decline and reconstitution kinetics of human blood CD14+ monocytes and dermal CD14+ cells in vivo supported their precursor-progeny relationship. The murine homologs of human dermal CD14+ cells are CD11b+CD64+ monocyte-derived macrophages. Human and mouse monocytes and macrophages were defined by highly conserved gene transcripts, which were distinct from DCs. The demonstration of monocyte-derived macrophages in the steady state in human tissue supports a conserved organization of human and mouse mononuclear phagocyte system. PMID:25200712

McGovern, Naomi; Schlitzer, Andreas; Gunawan, Merry; Jardine, Laura; Shin, Amanda; Poyner, Elizabeth; Green, Kile; Dickinson, Rachel; Wang, Xiao-nong; Low, Donovan; Best, Katie; Covins, Samuel; Milne, Paul; Pagan, Sarah; Aljefri, Khadija; Windebank, Martin; Saavedra, Diego Miranda; Larbi, Anis; Wasan, Pavandip Singh; Duan, Kaibo; Poidinger, Michael; Bigley, Venetia; Ginhoux, Florent; Collin, Matthew; Haniffa, Muzlifah

2014-01-01

125

Role of macrophages in early protective immune responses induced by two vaccines against foot and mouth disease.  

PubMed

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. PMID:21878353

Quattrocchi, V; Langellotti, C; Pappalardo, J S; Olivera, V; Di Giacomo, S; van Rooijen, N; Mongini, C; Waldner, C; Zamorano, P I

2011-11-01

126

Ginkgo biloba attenuates oxidative stress in macrophages and endothelial cells  

Microsoft Academic Search

The action of Ginkgo biloba extract (GBE) as an antioxidant was studied using various models of oxidative stress in macrophages and vascular endothelial cells. GBE was incubated with murine macrophages (J774) at 37°C and 5% CO2 for 1 h; oxidative burst was triggered by zymosan. The intensity of fluorescence was measured directly in 96-well plates using a computerized microplate fluorometer

Yongqi Rong; Zhaohui Geng; Benjamin H. S. Lau

1996-01-01

127

Macrophage migration inhibitory factor (MIF) plays a pivotal role in immunity against Salmonella typhimurium  

Microsoft Academic Search

The cytokine macrophage migration inhibitory factor (MIF) exerts a multitude of biological functions. Notably, it induces inflammation at the interface between the immune system and the hypothalamus-pituitary-adrenal stress axis. The role of MIF in infectious diseases is not understood completely. Here, we show that MIF-deficient (MIF\\/) knockout mice fail to control an infection with wild-type Salmonella typhimurium. Increased susceptibility was

Heidrun Koebernick; Leander Grode; John R. David; Wolfgang Rohde; Michael S. Rolph; Hans-Willi Mittrücker; Stefan H. E. Kaufmann

2002-01-01

128

Engagement of the Mannose Receptor by Tumoral Mucins Activates an Immune Suppressive Phenotype in Human Tumor-Associated Macrophages  

PubMed Central

Tumor-Associated Macrophages (TAMs) are abundantly present in the stroma of solid tumors and modulate several important biological processes, such as neoangiogenesis, cancer cell proliferation and invasion, and suppression of adaptive immune responses. Myeloid C-type lectin receptors (CLRs) constitute a large family of transmembrane carbohydrate-binding receptors that recognize pathogens as well as endogenous glycoproteins. Several lines of evidence demonstrate that some CLRs can inhibit the immune response. In this study we investigated TAM-associated molecules potentially involved in their immune suppressive activity. We found that TAMs isolated from human ovarian carcinoma samples predominantly express the CLRs Dectin-1, MDL-1, MGL, DCIR, and most abundantly the Mannose Receptor (MR). Components of carcinomatous ascites and purified tumoral mucins (CA125 and TAG-72) bound the MR and induced its internalization. MR engagement by tumoral mucins and by an agonist anti-MR antibody modulated cytokine production by TAM toward an immune-suppressive profile: increase of IL-10, absence of IL-12, and decrease of the Th1-attracting chemokine CCL3. This study highlights that tumoral mucin-mediated ligation of the MR on infiltrating TAM may contribute to their immune suppressive phenotype. PMID:21331365

Allavena, P.; Chieppa, M.; Bianchi, G.; Solinas, G.; Fabbri, M.; Laskarin, G.; Mantovani, A.

2010-01-01

129

Functional Proteomic Analysis for Regulatory T Cell Surveillance of the HIV-1-Infected Macrophage  

PubMed Central

Regulatory T cells (Treg) induce robust neuroprotection in murine models of neuroAIDS, in part, through eliciting anti-inflammatory responses for HIV-1-infected brain mononuclear phagocytes (MP; macrophage and microglia). Herein, using both murine and human primary cell cultures in proteomic and cell biologic tests, we report that Treg promotes such neuroprotection by an even broader range of mechanisms than previously seen including inhibition of virus release, killing infected MP, and inducing phenotypic cell switches. Changes in individual Treg-induced macrophage proteins were quantified by iTRAQ labeling followed by mass spectrometry identifications. Reduction in virus release paralleled the upregulation of interferon-stimulated gene 15, an ubiquitin-like protein involved in interferon-mediated antiviral immunity. Treg killed virus-infected macrophages through caspase-3 and granzyme and perforin pathways. Independently, Treg transformed virus-infected macrophages from an M1 to an M2 phenotype by down- and up- regulation of inducible nitric oxide synthase and arginase 1, respectively. Taken together, Treg affects a range of virus-infected MP functions. The observations made serve to challenge the dogma of solitary Treg immune suppressor functions and provides novel insights into how Treg affects adaptive immunosurveillance for control of end organ diseases, notably neurocognitive disorders associated with advanced viral infection. PMID:20954747

2010-01-01

130

The macrophage cell surface glyceraldehyde-3-phosphate dehydrogenase is a novel transferrin receptor.  

PubMed

The reticuloendothelial system plays a major role in iron metabolism. Despite this, the manner in which macrophages handle iron remains poorly understood. Mammalian cells utilize transferrin-dependent mechanisms to acquire iron via transferrin receptors 1 and 2 (TfR1 and TfR2) by receptor-mediated endocytosis. Here, we show for the first time that the glycolytic enzyme glyceraldehyde-3-phosphate dehydrogenase (GAPDH) is localized on human and murine macrophage cell surface. The expression of this surface GAPDH is regulated by the availability of iron in the medium. We further demonstrate that this GAPDH interacts with transferrin and the GAPDH-transferrin complex is subsequently internalized into the early endosomes. Our work sheds new light on the mechanisms involved in regulation of iron, vital for controlling numerous diseases and maintaining normal immune function. Thus, we propose an entirely new avenue for investigation with respect to transferrin uptake and regulation mechanisms in macrophages. PMID:17121833

Raje, Chaaya Iyengar; Kumar, Santosh; Harle, Arti; Nanda, Jagpreet Singh; Raje, Manoj

2007-02-01

131

Insulin Secretion is Regulated by the Glucose-Dependent Production of Islet beta Cell Macrophage Migration Inhibitory Factor  

Microsoft Academic Search

Macrophage migration inhibitory factor (MIF), originally identified as a cytokine secreted by T lymphocytes, was found recently to be both a pituitary hormone and a mediator released by immune cells in response to glucocorticoid stimulation. We report here that the insulin-secreting beta cell of the islets of Langerhans expresses MIF and that its production is regulated by glucose in a

Gerard Waeber; Thierry Calandra; Raphael Roduit; Jacques-Antoine Haefliger; Christophe Bonny; Nancy Thompson; Bernard Thorens; Evelyne Temler; Andreas Meinhardt; Michael Bacher; Christine N. Metz; Pascal Nicod; Richard Bucala

1997-01-01

132

CD14 influences host immune responses and alternative activation of macrophages during Schistosoma mansoni infection.  

PubMed

Antigen-presenting cell (APC) plasticity is critical for controlling inflammation in metabolic diseases and infections. The roles that pattern recognition receptors (PRRs) play in regulating APC phenotypes are just now being defined. We evaluated the expression of PRRs on APCs in mice infected with the helminth parasite Schistosoma mansoni and observed an upregulation of CD14 expression on macrophages. Schistosome-infected Cd14(-/-) mice showed significantly increased alternative activation of (M2) macrophages in the livers compared to infected wild-type (wt) mice. In addition, splenocytes from infected Cd14(-/-) mice exhibited increased production of CD4(+)-specific interleukin-4 (IL-4), IL-5, and IL-13 and CD4(+)Foxp3(+)IL-10(+) regulatory T cells compared to cells from infected wt mice. S. mansoni-infected Cd14(-/-) mice also presented with smaller liver egg granulomas associated with increased collagen deposition compared to granulomas in infected wt mice. The highest expression of CD14 was found on liver macrophages in infected mice. To determine if the Cd14(-/-) phenotype was in part due to increased M2 macrophages, we adoptively transferred wt macrophages into Cd14(-/-) mice and normalized the M2 and CD4(+) Th cell balance close to that observed in infected wt mice. Finally, we demonstrated that CD14 regulates STAT6 activation, as Cd14(-/-) mice had increased STAT6 activation in vivo, suggesting that lack of CD14 impacts the IL-4R?-STAT6 pathway, altering macrophage polarization during parasite infection. Collectively, these data identify a previously unrecognized role for CD14 in regulating macrophage plasticity and CD4(+) T cell biasing during helminth infection. PMID:24866794

Tundup, Smanla; Srivastava, Leena; Nagy, Tamas; Harn, Donald

2014-08-01

133

Lymphoid tissue and plasmacytoid dendritic cells and macrophages do not share a common macrophage-dendritic cell-restricted progenitor.  

PubMed

The relationship between dendritic cells (DCs) and macrophages is often debated. Here we ask whether steady-state, lymphoid-tissue-resident conventional DCs (cDCs), plasmacytoid DCs (pDCs), and macrophages share a common macrophage-DC-restricted precursor (MDP). Using new clonal culture assays combined with adoptive transfer, we found that MDP fractions isolated by previous strategies are dominated by precursors of macrophages and monocytes, include some multipotent precursors of other hematopoietic lineages, but contain few precursors of resident cDCs and pDCs and no detectable common precursors restricted to these DC types and macrophages. Overall we find no evidence for a common restricted MDP leading to both macrophages and FL-dependent, resident cDCs and pDCs. PMID:25035955

Sathe, Priyanka; Metcalf, Donald; Vremec, David; Naik, Shalin H; Langdon, Wallace Y; Huntington, Nicholas D; Wu, Li; Shortman, Ken

2014-07-17

134

Brevetoxin-2 induces an inflammatory response in an alveolar macrophage cell line.  

PubMed

Brevetoxins, the algal toxins produced by Karenia brevis during red tide blooms, adversely impact health following ingestion or inhalation. Inhalation of brevetoxins results in a variety of acute symptoms including coughing, wheezing, and shortness of breath. Analysis of manatee lungs following death by purported brevetoxicosis has identified brevetoxin accumulation within macrophages, with pathological manifestions of lung congestion, inflammation, and edema. The goals of this work were to specifically examine effects of brevetoxin-2 on alveolar macrophages, a key cell in responding to toxins in the lung, as well as to determine if brevetoxin-2 results in an inflammatory response and/or direct cytotoxicity. Exposure of an alveolar macrophage cell line (MH-S) to an environmentally and physiologically relevant dose of brevetoxin-2 (0.5microg/ml) did not significantly alter cellular growth over a 24h time period. However, exposure of MH-S cells to brevetoxin-2 for 6h increased phagocytosis of latex beads, increased secretion of interleukin (IL)-2, IL-4, and tumor necrosis factor-alpha, and decreased secretion of IL-5. Very few changes were seen in gene expression following 3 or 6h exposure to brevetoxin-2. These results show that brevetoxin-2 induced an immune response indicative of inflammation in an alveolar macrophage cell line, indicating that inhalation of brevetoxin-2 may lead to lung inflammation through an alveolar macrophage-initiated pathway. PMID:20655277

Sas, Kelli M; Baatz, John E

2010-09-01

135

Cell mechanics of alveolar epithelial cells (AECs) and macrophages (AMs).  

PubMed

Cell mechanics provides an integrated view of many biological phenomena which are intimately related to cell structure and function. Because breathing constitutes a sustained motion synonymous with life, pulmonary cells are normally designed to support permanent cyclic stretch without breaking, while receiving mechanical cues from their environment. The authors study the mechanical responses of alveolar cells, namely epithelial cells and macrophages, exposed to well-controlled mechanical stress in order to understand pulmonary cell response and function. They discuss the principle, advantages and limits of a cytoskeleton-specific micromanipulation technique, magnetic bead twisting cytometry, potentially applicable in vivo. They also compare the pertinence of various models (e.g., rheological; power law) used to extract cell mechanical properties and discuss cell stress/strain hardening properties and cell dynamic response in relation to the structural tensegrity model. Overall, alveolar cells provide a pertinent model to study the biological processes governing cellular response to controlled stress or strain. PMID:18565804

Féréol, Sophie; Fodil, Redouane; Pelle, Gabriel; Louis, Bruno; Isabey, Daniel

2008-11-30

136

Evolution of B Cell Immunity  

PubMed Central

Two types of adaptive immune strategies are known to have evolved in vertebrates: the VLR-based system, which is present in jawless organisms and is mediated by VLRA and VLRB lymphocytes, and the BCR/TCR-based system, which is present in jawed species and is provided by B and T cell receptors expressed on B and T cells, respectively. Here we summarize features of B cells and their predecessors in the different animal phyla, focusing the review on B cells from jawed vertebrates. We point out the critical role of nonclassical species and comparative immunology studies in the understanding of B cell immunity. Because nonclassical models include species relevant to veterinary medicine, basic science research performed in these animals contributes to the knowledge required for the development of more efficacious vaccines against emerging pathogens. PMID:25340015

Sunyer, J. Oriol

2013-01-01

137

Stimulatory Effects of Polysaccharide Fraction from Solanum nigrum on RAW 264.7 Murine Macrophage Cells  

PubMed Central

The polysaccharide fraction from Solanum nigrum Linne has been shown to have antitumor activity by enhancing the CD4+/CD8+ ratio of the T-lymphocyte subpopulation. In this study, we analyzed a polysaccharide extract of S. nigrum to determine its modulating effects on RAW 264.7 murine macrophage cells since macrophages play a key role in inducing both innate and adaptive immune responses. Crude polysaccharide was extracted from the stem of S. nigrum and subjected to ion-exchange chromatography to partially purify the extract. Five polysaccharide fractions were then subjected to a cytotoxicity assay and a nitric oxide production assay. To further analyze the ability of the fractionated polysaccharide extract to activate macrophages, the phagocytosis activity and cytokine production were also measured. The polysaccharide fractions were not cytotoxic, but all of the fractions induced nitric oxide in RAW 264.7 cells. Of the five fractions tested, SN-ppF3 was the least toxic and also induced the greatest amount of nitric oxide, which was comparable to the inducible nitric oxide synthase expression detected in the cell lysate. This fraction also significantly induced phagocytosis activity and stimulated the production of tumor necrosis factor-? and interleukin-6. Our study showed that fraction SN-ppF3 could classically activate macrophages. Macrophage induction may be the manner in which polysaccharides from S. nigrum are able to prevent tumor growth. PMID:25299340

Razali, Faizan Naeem; Ismail, Amirah; Abidin, Nurhayati Zainal; Shuib, Adawiyah Suriza

2014-01-01

138

Macrophages - Key Cells in the Response to Wear Debris from Joint Replacements  

PubMed Central

The generation of wear debris is an inevitable result of normal usage of joint replacements. Wear debris particles stimulate local and systemic biological reactions resulting in chronic inflammation, periprosthetic bone destruction, and eventually, implant loosening and revision surgery. The latter may be indicated in up to 15% patients in the decade following the arthroplasty using conventional polyethylene. Macrophages play multiple roles in both inflammation and in maintaining tissue homeostasis. As sentinels of the innate immune system, they are central to the initiation of this inflammatory cascade, characterized by the release of pro-inflammatory and pro-osteoclastic factors. Similar to the response to pathogens, wear particles elicit a macrophage response, based on the unique properties of the cells belonging to this lineage, including sensing, chemotaxis, phagocytosis, and adaptive stimulation. The biological processes involved are complex, redundant, both local and systemic, and highly adaptive. Cells of the monocyte/macrophage lineage are implicated in this phenomenon, ultimately resulting in differentiation and activation of bone resorbing osteoclasts. Simultaneously, other distinct macrophage populations inhibit inflammation and protect the bone-implant interface from osteolysis. Here, the current knowledge about the physiology of monocyte/macrophage lineage cells is reviewed. In addition, the pattern and consequences of their interaction with wear debris and the recent developments in this field are presented. PMID:23568608

Nich, Christophe; Takakubo, Yuya; Pajarinen, Jukka; Ainola, Mari; Salem, Abdelhakim; Sillat, Tarvo; Rao, Allison J.; Raska, Milan; Tamaki, Yasunobu; Takagi, Michiaki; Konttinen, Yrjo T.; Goodman, Stuart B.; Gallo, Jiri

2013-01-01

139

Stimulatory Effects of Polysaccharide Fraction from Solanum nigrum on RAW 264.7 Murine Macrophage Cells.  

PubMed

The polysaccharide fraction from Solanum nigrum Linne has been shown to have antitumor activity by enhancing the CD4+/CD8+ ratio of the T-lymphocyte subpopulation. In this study, we analyzed a polysaccharide extract of S. nigrum to determine its modulating effects on RAW 264.7 murine macrophage cells since macrophages play a key role in inducing both innate and adaptive immune responses. Crude polysaccharide was extracted from the stem of S. nigrum and subjected to ion-exchange chromatography to partially purify the extract. Five polysaccharide fractions were then subjected to a cytotoxicity assay and a nitric oxide production assay. To further analyze the ability of the fractionated polysaccharide extract to activate macrophages, the phagocytosis activity and cytokine production were also measured. The polysaccharide fractions were not cytotoxic, but all of the fractions induced nitric oxide in RAW 264.7 cells. Of the five fractions tested, SN-ppF3 was the least toxic and also induced the greatest amount of nitric oxide, which was comparable to the inducible nitric oxide synthase expression detected in the cell lysate. This fraction also significantly induced phagocytosis activity and stimulated the production of tumor necrosis factor-? and interleukin-6. Our study showed that fraction SN-ppF3 could classically activate macrophages. Macrophage induction may be the manner in which polysaccharides from S. nigrum are able to prevent tumor growth. PMID:25299340

Razali, Faizan Naeem; Ismail, Amirah; Abidin, Nurhayati Zainal; Shuib, Adawiyah Suriza

2014-01-01

140

Replication of macrophage-tropic and T-cell-tropic strains of human immunodeficiency virus type 1 is augmented by macrophage-endothelial cell contact.  

PubMed Central

Macrophages perform a central role in the pathogenesis of human immunodeficiency virus type 1 (HIV-1) infection and have been implicated as the cell type most prominent in the development of central nervous system impairment. In this study, we evaluated the effect of interaction between macrophages and endothelial cells on HIV-1 replication. Upregulation of HIV-1 replication was consistently observed in monocyte-derived macrophages (hereafter called macrophages) cocultured with either umbilical vein endothelial cells or brain microvascular endothelial cells. HIV-1 p24 antigen production of laboratory-adapted strains and patient-derived isolates was increased 2- to 1,000-fold in macrophage-endothelial cocultures, with little or no detectable replication in cultures containing endothelial cells only. The upregulation of HIV-1 in macrophage-endothelial cocultures was observed not only for viruses with the non-syncytium-inducing, macrophage-tropic phenotype but also for viruses previously characterized as syncytium inducing and T-cell tropic. In contrast, cocultures of macrophages with glioblastoma, astrocytoma, cortical neuronal, fibroblast, and placental cells failed to increase HIV-1 replication. Enhancement of HIV-1 replication in macrophage-endothelial cocultures required cell-to-cell contact; conditioned media from endothelial cells or macrophage-endothelial cocultures failed to augment HIV-1 replication in macrophages. Additionally, antibody to leukocyte function-associated antigen (LFA-1), a macrophage-endothelial cell adhesion molecule, inhibited the enhanced HIV-1 replication in macrophage-endothelial cell cocultures. Thus, these data indicate that macrophage-endothelial cell contact enhances HIV-1 replication in macrophages for both macrophage-tropic and previously characterized T-cell-tropic strains and that antibody against LFA-1 can block the necessary cell-to-cell interaction required for the observed upregulation. These findings may have important implications for understanding the ability of HIV-1 to replicate efficiently in tissue macrophages, including those in the brain and at the blood-brain barrier. PMID:7884860

Gilles, P N; Lathey, J L; Spector, S A

1995-01-01

141

Aminopeptidase N (CD13) Is Involved in Phagocytic Processes in Human Dendritic Cells and Macrophages  

PubMed Central

Aminopeptidase N (APN or CD13) is a membrane ectopeptidase expressed by many cell types, including myelomonocytic lineage cells: monocytes, macrophages, and dendritic cells. CD13 is known to regulate the biological activity of various peptides by proteolysis, and it has been proposed that CD13 also participates in several functions such as angiogenesis, cell adhesion, metastasis, and tumor invasion. We had previously reported that, in human monocytes and macrophages, CD13 modulates the phagocytosis mediated by receptors for the Fc portion of IgG antibodies (Fc?Rs). In this work, we analyzed the possible interaction of CD13 with other phagocytic receptors. We found out that the cross-linking of CD13 positively modulates the phagocytosis mediated by receptors of the innate immune system, since a significant increase in the phagocytosis of zymosan particles or heat-killed E. coli was observed when CD13 was cross-linked using anti-CD13 antibodies, in both macrophages and dendritic cells. Also, we observed that, during the phagocytosis of zymosan, CD13 redistributes and is internalized into the phagosome. These findings suggest that, besides its known functions, CD13 participates in phagocytic processes in dendritic cells and macrophages. PMID:24063007

Villasenor-Cardoso, Monica I.; Frausto-Del-Rio, Dulce A.

2013-01-01

142

Activated macrophages induce structural abnormalities of the T cell receptor-CD3 complex  

PubMed Central

The mechanism of the structural alterations of the T cell receptor (TCR)-CD3 complex, which appear to be greatly responsible for immunosuppression in the tumor-bearing status, was investigated in tumor-bearing mice. Splenic T cells from tumor-bearing hosts lost the expression of the CD3 zeta chain without being replaced by FcR gamma, despite the normal expression of other components of the TCR complex. Tumor growth induced the accumulation of non-T, non-B cells in the spleen in correlation with the loss of zeta. Those cells were found to be macrophages that were able to induce the loss of zeta, as well as structural changes of CD3 gamma delta epsilon, even in freshly isolated normal T cells by cell contact-dependent interaction. More importantly, macrophages activated with zymosan A+LPS but not residential macrophages were able to induce the similar abnormality of the TCR complex. These results indicate that macrophages in certain activation stages play a crucial role in causing an abnormal TCR complex in tumor- bearing conditions, as well as in regulating the structure of the TCR complex in immune responses. PMID:7722462

1995-01-01

143

Induction of macrophage cell-cycle arrest and apoptosis by humic acid.  

PubMed

Humic acid (HA) in well water is associated with Blackfoot disease and various cancers. Previously, we reported that acute humic acid exposure (25-200 µg/mL for 24 hr) induces inflammation in RAW264.7 macrophages. In this study, we observed that prolonged (72 hr) HA exposure (25-200 µg/mL) induces cell-cycle arrest and apoptosis in cultured RAW264.7 cells. We also observed that exposing macrophages to HA arrests cells in the G2 /M phase of the cell cycle by reducing cyclin A/B1 , Cdc2, and Cdc25C levels. Treating macrophages with HA triggers a sequence of events characteristic of apoptotic cell death including loss of cell viability, morphological changes, internucleosomal DNA fragmentation, sub-G1 accumulation. Molecular markers of apoptosis associated with mitochondrial dysfunction were similarly observed, including cytochrome c release, caspase-3 or caspase-9 activation, and Bcl-2/Bax dysregulation. In addition to the mitochondrial pathway, HA-induced apoptosis may also be mediated through the death receptor and ER stress pathways, as evidence by induction of Fas, caspase-8, caspase-4, and caspase-12 activity. HA also upregulates p53 expression and causes DNA damage as assessed by the comet assay. These findings yield new insight into the mechanisms by which HA exposure may trigger atherosclerosis through modulation of the macrophage-mediated immune system. Environ. Mol. Mutagen. 55:741-750, 2014. © 2014 Wiley Periodicals, Inc. PMID:25179584

Yang, Hsin-Ling; Huang, Pei-Jane; Chen, Ssu-Ching; Cho, Hsin-Ju; Kumar, K J Senthil; Lu, Fung-Jou; Chen, Chih-Sheng; Chang, Chia-Ting; Hseu, You-Cheng

2014-12-01

144

Macrophage characteristics of stem cells revealed by transcriptome profiling  

SciTech Connect

We previously showed that the phenotypes of adipocyte progenitors and macrophages were close. Using functional analyses and microarray technology, we first tested whether this intriguing relationship was specific to adipocyte progenitors or could be shared with other progenitors. Measurements of phagocytic activity and gene profiling analysis of different progenitor cells revealed that the latter hypothesis should be retained. These results encouraged us to pursue and to confirm our analysis with a gold-standard stem cell population, embryonic stem cells or ESC. The transcriptomic profiles of ESC and macrophages were clustered together, unlike differentiated ESC. In addition, undifferentiated ESC displayed higher phagocytic activity than other progenitors, and they could phagocytoze apoptotic bodies. These data suggest that progenitors and stem cells share some characteristics of macrophages. This opens new perspectives on understanding stem cell phenotype and functionalities such as a putative role of stem cells in tissue remodeling by discarding dead cells but also their immunomodulation or fusion properties.

Charriere, Guillaume M. [UMR 5018 CNRS-UPS, IFR31, Bat L1, CHU Rangueil, 31059 Toulouse Cedex 9 (France); Cousin, Beatrice [UMR 5018 CNRS-UPS, IFR31, Bat L1, CHU Rangueil, 31059 Toulouse Cedex 9 (France); Arnaud, Emmanuelle [UMR 5018 CNRS-UPS, IFR31, Bat L1, CHU Rangueil, 31059 Toulouse Cedex 9 (France); Saillan-Barreau, Corinne [UMR 5018 CNRS-UPS, IFR31, Bat L1, CHU Rangueil, 31059 Toulouse Cedex 9 (France); Andre, Mireille [UMR 5018 CNRS-UPS, IFR31, Bat L1, CHU Rangueil, 31059 Toulouse Cedex 9 (France); Massoudi, Ali [UMR 6543 CNRS, Universite de Nice-Sophia Antipolis, Faculte des Sciences, Parc Valrose, 06108 Nice Cedex 2 (France); Dani, Christian [UMR 6543 CNRS, Universite de Nice-Sophia Antipolis, Faculte des Sciences, Parc Valrose, 06108 Nice Cedex 2 (France); Penicaud, Luc [UMR 5018 CNRS-UPS, IFR31, Bat L1, CHU Rangueil, 31059 Toulouse Cedex 9 (France); Casteilla, Louis [UMR 5018 CNRS-UPS, IFR31, Bat L1, CHU Rangueil, 31059 Toulouse Cedex 9 (France)]. E-mail: casteil@toulouse.inserm.fr

2006-10-15

145

Distinct spatial distribution of microglia and macrophages following mesenchymal stem cell implantation in mouse brain.  

PubMed

Although implantation of cellular material in the central nervous system (CNS) is a key direction in CNS regenerative medicine, this approach is currently limited by the occurrence of strong endogenous immune cell responses. In a model of mesenchymal stem cell (MSC) grafting in the CNS of immune-competent mice, we previously described that MSC grafts become highly surrounded and invaded by Iba1(+) myeloid cells (microglia and/or macrophages). Here, following grafting of blue fluorescent protein (BFP)-expressing MSC in the CNS of CX3CR1(+/-) and CX3CR1(-/-) mice, our results indicate: (1) that the observed inflammatory response is independent of the fractalkine signalling axis, and (2) that a significant spatial distribution of Iba1(+) inflammatory cells occurs, in which Iba1(+) CX3CR1(+) myeloid cells mainly surround the MSC graft and Iba1(+) CX3CR1(-) myeloid cells mainly invade the graft at 10 days post transplantation. Although Iba1(+) CX3CR1(+) myeloid cells are considered to be of resident microglial origin, Iba1(+) CX3CR1(-) myeloid cells are most likely of peripheral monocyte/macrophage origin. In order to confirm the latter, we performed MSC-BFP grafting experiments in the CNS of eGFP(+) bone marrow chimeric C57BL/6 mice. Analysis of MSC-BFP grafts in the CNS of these mice confirmed our observation that peripheral monocytes/macrophages invade the MSC graft and that resident microglia surround the MSC graft site. Furthermore, analysis of major histocompatibility complex class II (MHCII) expression revealed that mainly macrophages, but not microglia, express this M1 pro-inflammatory marker in the context of MSC grafting in the CNS. These results again highlight the complexity of cell implantation immunology in the CNS. PMID:24983456

Le Blon, Debbie; Hoornaert, Chloé; Daans, Jasmijn; Santermans, Eva; Hens, Niel; Goossens, Herman; Berneman, Zwi; Ponsaerts, Peter

2014-09-01

146

Immune cell trafficking from the brain maintains CNS immune tolerance.  

PubMed

In the CNS, no pathway dedicated to immune surveillance has been characterized for preventing the anti-CNS immune responses that develop in autoimmune neuroinflammatory disease. Here, we identified a pathway for immune cells to traffic from the brain that is associated with the rostral migratory stream (RMS), which is a forebrain source of newly generated neurons. Evaluation of fluorescently labeled leukocyte migration in mice revealed that DCs travel via the RMS from the CNS to the cervical LNs (CxLNs), where they present antigen to T cells. Pharmacologic interruption of immune cell traffic with the mononuclear cell-sequestering drug fingolimod influenced anti-CNS T cell responses in the CxLNs and modulated experimental autoimmune encephalomyelitis (EAE) severity in a mouse model of multiple sclerosis (MS). Fingolimod treatment also induced EAE in a disease-resistant transgenic mouse strain by altering DC-mediated Treg functions in CxLNs and disrupting CNS immune tolerance. These data describe an immune cell pathway that originates in the CNS and is capable of dampening anti-CNS immune responses in the periphery. Furthermore, these data provide insight into how fingolimod treatment might exacerbate CNS neuroinflammation in some cases and suggest that focal therapeutic interventions, outside the CNS have the potential to selectively modify anti-CNS immunity. PMID:24569378

Mohammad, Mohammad G; Tsai, Vicky W W; Ruitenberg, Marc J; Hassanpour, Masoud; Li, Hui; Hart, Prue H; Breit, Samuel N; Sawchenko, Paul E; Brown, David A

2014-03-01

147

Comparison of immune response generated against Japanese encephalitis virus envelope protein expressed by DNA vaccines under macrophage associated versus ubiquitous expression promoters  

PubMed Central

Background Japanese encephalitis virus (JEV) is the leading cause of viral encephalitis, with ~50,000 cases reported annually worldwide. Vaccination is the only measure for prevention. Recombinant vaccines are an efficient and safe alternative for formalin inactivated or live attenuated vaccines. Nowadays, incorporation of molecular adjuvants has been the main strategy for melioration of vaccines. Our attempt of immunomodulation is based on targeting antigen presenting cells (APC) "majorly macrophages" by using macrosialin promoter. We have compared the immune response of the constructed plasmids expressing JEV envelope (E) protein under the control of aforesaid promoter and cytomegalovirus (CMV) immediate early promoter in mouse model. Protection of immunized mice from lethal challenge with JEV was also studied. Results The E protein was successfully expressed in the macrophage cell line and was detected using immunofluorescence assay (IFA) and Western blotting. APC expressing promoter showed comparable expression to CMV promoter. Immunization of mice with either of the plasmids exhibited induction of variable JEV neutralizing antibody titres and provided protection from challenge with a lethal dose of JEV. Immune splenocytes showed proliferative response after stimulation with the JEV antigen (Ag), however, it was higher for CMV promoter. The magnitude of immunity provided by APC dominant promoter was non-significantly lower in comparison to CMV promoter. More importantly, immune response directed by APC promoter was skewed towards Th1 type in comparison to CMV promoter, this was evaluated by cytokine secretion profile of immune splenocytes stimulated with JEV Ag. Conclusions Thus, our APC-expressing DNA vaccination approach induces comparable immunity in comparison to ubiquitous promoter construct. The predominant Th1 type immune responses provide opportunities to further test its potency suitable for response in antiviral or anticancer vaccines. PMID:21806845

2011-01-01

148

Macrophages eliminate circulating tumor cells after monoclonal antibody therapy  

PubMed Central

The use of monoclonal antibodies (mAbs) as therapeutic tools has increased dramatically in the last decade and is now one of the mainstream strategies to treat cancer. Nonetheless, it is still not completely understood how mAbs mediate tumor cell elimination or the effector cells that are involved. Using intravital microscopy, we found that antibody-dependent phagocytosis (ADPh) by macrophages is a prominent mechanism for removal of tumor cells from the circulation in a murine tumor cell opsonization model. Tumor cells were rapidly recognized and arrested by liver macrophages (Kupffer cells). In the absence of mAbs, Kupffer cells sampled tumor cells; however, this sampling was not sufficient for elimination. By contrast, antitumor mAb treatment resulted in rapid phagocytosis of tumor cells by Kupffer cells that was dependent on the high-affinity IgG-binding Fc receptor (Fc?RI) and the low-affinity IgG-binding Fc receptor (Fc?RIV). Uptake and intracellular degradation were independent of reactive oxygen or nitrogen species production. Importantly, ADPh prevented the development of liver metastases. Tumor cell capture and therapeutic efficacy were lost after Kupffer cell depletion. Our data indicate that macrophages play a prominent role in mAb-mediated eradication of tumor cells. These findings may help to optimize mAb therapeutic strategies for patients with cancer by helping us to aim to enhance macrophage recruitment and activity. PMID:24430180

Gul, Nuray; Babes, Liane; Siegmund, Kerstin; Korthouwer, Rianne; Bogels, Marijn; Braster, Rens; Vidarsson, Gestur; ten Hagen, Timo L.M.; Kubes, Paul; van Egmond, Marjolein

2014-01-01

149

Multiple Defects of Immune Cell Function in Mice with Disrupted Interferon-gamma Genes  

Microsoft Academic Search

Interferon-gamma (IFN-gamma) is a pleiotrophic cytokine with immunomodulatory effects on a variety of immune cells. Mice with a targeted disruption of the IFN-gamma gene were generated. These mice developed normally and were healthy in the absence of pathogens. However, mice deficient in IFN-gamma had impaired production of macrophage antimicrobial products and reduced expression of macrophage major histocompatibility complex class II

Dyana K. Dalton; Sharon Pitts-Meek; Satish Keshav; Irene S. Figari; Allan Bradley; Timothy A. Stewart

1993-01-01

150

Susceptibility of rhabdomyosarcoma cells to macrophage-mediated cytotoxicity.  

PubMed

The prognosis of advanced stage rhabdomyosarcoma (RMS) is still sobering. In recent years, outcome has not been further improved by conventional therapy. Therefore, novel treatment options such as macrophage-directed immunotherapy have to be investigated. The aim of this study was to analyze the phagocytosis of RMS cells by macrophages and to modulate the susceptibility using monoclonal antibodies and cytotoxic drugs.   Expression of the macrophage activating ligand calreticulin and CD47, the counterpart of the inhibitory receptor SIRP?, was analyzed with Affymetrix mRNA expression arrays and immunohistochemistry on 11 primary RMS samples. Results were verified in two RMS cell lines using flow cytometry and immunocytochemistry. Macrophage cytotoxic activity was quantified by a MTT colorimetric assay in co-culture experiments of RMS cells with monocyte-derived, GM-CSF stimulated macrophages. Gene expression analysis and immunohistochemistry revealed a high expression of CD47 and calreticulin in alveolar and embryonal RMS tissue specimens. Extracellular expression of CD47 on RMS cell lines was confirmed by flow cytometry, whereas calreticulin was exclusively detected in the endoplasmatic reticulum. After co-culturing of RMS cells with macrophages, viability dropped to 50-60%. Macrophage-mediated cytotoxicity was not influenced by a blocking antibody against CD47. However, susceptibility was significantly enhanced after pre-treatment of RMS cells with the anthracycline drug doxorubicin. Furthermore, translocation of calreticulin onto the cell surface was detected by flow cytometry. The immunologic effect of doxorubicin may improve the efficacy of adoptive cellular immunotherapy and chemotherapy of childhood RMS. PMID:22737603

Herrmann, Delia; Seitz, Guido; Fuchs, Jörg; Armeanu-Ebinger, Sorin

2012-05-01

151

Induction of Macrophage-Like Immunosuppressive Cells from Mouse ES Cells That Contribute to Prolong Allogeneic Graft Survival  

PubMed Central

Recent progress in regenerative medicine has enabled the utilization of pluripotent stem cells (PSCs) such as embryonic stem cells (ESCs) as a donor resource for transplantation. However, immune suppression is still needed when the donor-recipient combination is allogeneic. Protection of ESCs-derived grafts from host immune response might be achieved thought the utilization of immunosuppressive cells generated from ESCs. In the present study, we show that a certain fraction of immunosuppressive cells can be generated from ESCs and help to suppress immune response against allogeneic grafts. ESCs-derived suppressor cells (ES-SCs) resembled macrophages in terms of cell surface molecule and gene expressions. Furthermore, gene expression analysis including microarray showed that ES-SCs have M1/M2 hybrid phenotype with high expression of genes correlated to immunosuppression of T cell response. Indeed, ES-SCs were effective to block allogeneic T cell proliferation in a nitric oxide-dependent manner, and prolonged the survival of ESCs-derived embryoid bodies or cardiomyocytes grafts transplanted into mouse kidney capsule. Thus, we consider the potential use of these ESCs-derived macrophage-like immunosuppressive cells as cellular therapies to promote long-term graft survival in future therapies. PMID:25356669

Sasaki, Hajime; Tsuji, Hyuma; Otsuka, Ryo; Baghdadi, Muhammad; Kojo, Satoshi; Chikaraishi, Tatsuya; Seino, Ken-ichiro

2014-01-01

152

Therapeutic Immunization with HIV1 Tat Reduces Immune Activation and Loss of Regulatory T-Cells and Improves Immune Function in Subjects on HAART  

Microsoft Academic Search

Although HAART suppresses HIV replication, it is often unable to restore immune homeostasis. Consequently, non-AIDS-defining diseases are increasingly seen in treated individuals. This is attributed to persistent virus expression in reservoirs and to cell activation. Of note, in CD4+ T cells and monocyte-macrophages of virologically-suppressed individuals, there is continued expression of multi-spliced transcripts encoding HIV regulatory proteins. Among them, Tat

Barbara Ensoli; Stefania Bellino; Antonella Tripiciano; Olimpia Longo; Vittorio Francavilla; Simone Marcotullio; Aurelio Cafaro; Orietta Picconi; Giovanni Paniccia; Arianna Scoglio; Angela Arancio; Cristina Ariola; Maria J. Ruiz Alvarez; Massimo Campagna; Donato Scaramuzzi; Cristina Iori; Roberto Esposito; Cristina Mussini; Florio Ghinelli; Laura Sighinolfi; Guido Palamara; Alessandra Latini; Gioacchino Angarano; Nicoletta Ladisa; Fabrizio Soscia; Vito S. Mercurio; Adriano Lazzarin; Giuseppe Tambussi; Raffaele Visintini; Francesco Mazzotta; Massimo di Pietro; Massimo Galli; Stefano Rusconi; Giampiero Carosi; Carlo Torti; Giovanni di Perri; Stefano Bonora; Fabrizio Ensoli; Enrico Garaci; Kim J. Hasenkrug

2010-01-01

153

Specific mediation of cellular immunity to Toxoplasma gondii in somatic cells of mice.  

PubMed Central

Lymphocytes from mice immunized against Toxoplasma gondii protected T. gondii-infected macrophage and kidney cell cultures. After contact with antigens, supernatants of such immune lymphocytes, also contained a factor protective for T. gondii-infected macrophages and kidney cells. Supernatants were protective only when the lymphocytes and kidneys cells were isogeneic. Protection was specific in that supernatants from only T. gondii-immune, but not Besnoitia jellisoni-immune, lymphocytes provided protection against toxoplasmosis. Sixteen to 24 h were required for an appreciable amount of protective factor to be secreted; a similar absorption time was necessary for kidney cells to be protected. Peritoneal lymphocyte lysates, prepared as transfer factor, contained protective substances with a potency similar to that of lymphocyte supernatants, which were also strain restricted in their effect. PMID:6500716

Chinchilla, M; Frenkel, J K

1984-01-01

154

Ischemia/reperfusion injury: The role of immune cells  

PubMed Central

Ischemia/reperfusion (I/R) injury is an inflammatory condition that is characterized by innate immunity and an adaptive immune response. This review is focused on the acute inflammatory response in I/R injury, and also the adaptive immunological mechanisms in chronic ischemic disease that lead to increased vulnerability during acute events, in relation to the cell types that have been shown to mediate innate immunity to an adaptive immune response in I/R, specifically myocardial infarction. Novel aspects are also highlighted in respect to the mechanisms within the cardiovascular system and cardiovascular risk factors that may be involved in the inflammatory response accompanying myocardial infarction. Experimental myocardial I/R has suggested that immune cells may mediate reperfusion injury. Specifically, monocytes, macrophages, T-cells, mast cells, platelets and endothelial cells are discussed with reference to the complement cascade, toll-like receptors, cytokines, oxidative stress, renin-angiotensin system, and in reference to the microvascular system in the signaling mechanisms of I/R. Finally, the findings of the data summarized in this review are most important for possible translation into clinical cardiology practice and possible avenues for drug development. PMID:21160610

Zuidema, Mozow Y; Zhang, Cuihua

2010-01-01

155

Microglia in the giant cell encephalitis of acquired immune deficiency syndrome: proliferation, infection and fusion  

Microsoft Academic Search

The autopsied brains of three homosexual men with acquired immune deficiency syndrome (AIDS), progressive encephalopathy and widespread multinucleated giant cell encephalitis were investigated by lectin and immunohistochemical methods to ascertain the cellular distribution of a human immunodeficiency virus (HIV) core protein, p25. Abundant viral antigen was present in all brains, limited to perivascular macrophages, microglial and multinucleated cells, some bearing

J. Michaels; R. W. Price; M. K. Rosenblum

1988-01-01

156

Impact of carbon nanotubes and graphene on immune cells  

PubMed Central

It has been recently proposed that nanomaterials, alone or in concert with their specific biomolecular conjugates, can be used to directly modulate the immune system, therefore offering a new tool for the enhancement of immune-based therapies against infectious disease and cancer. Here, we revised the publications on the impact of functionalized carbon nanotubes (f-CNTs), graphene and carbon nanohorns on immune cells. Whereas f-CNTs are the nanomaterial most widely investigated, we noticed a progressive increase of studies focusing on graphene in the last couple of years. The majority of the works (56%) have been carried out on macrophages, following by lymphocytes (30% of the studies). In the case of lymphocytes, T cells were the most investigated (22%) followed by monocytes and dendritic cells (7%), mixed cell populations (peripheral blood mononuclear cells, 6%), and B and natural killer (NK) cells (1%). Most of the studies focused on toxicity and biocompatibility, while mechanistic insights on the effect of carbon nanotubes on immune cells are generally lacking. Only very recently high-throughput gene-expression analyses have shed new lights on unrecognized effects of carbon nanomaterials on the immune system. These investigations have demonstrated that some f-CNTs can directly elicitate specific inflammatory pathways. The interaction of graphene with the immune system is still at a very early stage of investigation. This comprehensive state of the art on biocompatible f-CNTs and graphene on immune cells provides a useful compass to guide future researches on immunological applications of carbon nanomaterials in medicine. PMID:24885781

2014-01-01

157

Accumulation of macrophage-like cells expressing NG2 proteoglycan and Iba1 in ischemic core of rat brain after transient middle cerebral artery occlusion  

Microsoft Academic Search

Although neurons and glia inevitably undergo degeneration in the core of ischemic lesions, many cells, particularly immune cells, infiltrate the core and survive in it. Such infiltrating cells may play certain roles in the regeneration and repair of damaged brain tissues. In this study, we characterized macrophage-like cells that accumulated in the ischemic core of a rat brain whose right

Hiroaki Matsumoto; Yoshiaki Kumon; Hideaki Watanabe; Takanori Ohnishi; Masachika Shudou; Miao Chuai; Yoshinori Imai; Hisaaki Takahashi; Junya Tanaka

2008-01-01

158

Prostaglandin E2 in tick saliva regulates macrophage cell migration and cytokine profile  

PubMed Central

Background Ticks are obligate hematophagous ectoparasites that suppress the host’s immune and inflammatory responses by secreting immuno-modulatory and anti-inflammatory molecules in their saliva. In previous studies we have shown that tick salivary gland extract (SGE) and saliva from Dermacentor variabilis have distinct effects on platelet-derived growth factor (PDGF)-stimulated IC-21 macrophage and NIH3T3-L1 fibroblast migration. Since tick saliva contains a high concentration of prostaglandin E2 (PGE2), a potent modulator of inflammation, we used a PGE2 receptor antagonist to evaluate the role of PGE2 in the different migratory responses induced by saliva and its impact on macrophage cytokine profile. Methods Adult ticks were fed on female New Zealand white rabbits for 5-8 days. Female ticks were stimulated with dopamine/theophylline to induce salivation and saliva was pooled. Competitive enzyme immunoassays (EIA) were used to measure saliva PGE2 content and the changes in macrophage intracellular cyclic adenosine monophosphate (cAMP) levels. The effects of tick saliva on macrophage and fibroblast migration were assessed in the absence and presence of the PGE2 receptor antagonist, AH 6809, using blind well chamber assays. A cytokine antibody array was used to examine the effects of tick saliva on macrophage cytokine secretion. Statistical significance was determined by one-way ANOVA; Student Newman-Kuels post-test was used for multiple comparisons. Results The saliva-induced increase in PDGF-stimulated macrophage migration was reversed by AH 6809. The inhibition of PDGF-stimulated fibroblast migration by saliva was also antagonist-sensitive. Tick saliva induced macrophages to secrete copious amounts of PGE2, and conditioned medium from these cells caused an AH 6809-sensitive inhibition of stimulated fibroblast migration, showing that macrophages can regulate fibroblast activity. We show that tick saliva decreased the secretion of the pro-inflammatory cytokines regulated and normal T cell expressed and secreted (RANTES/CCL5), tumor necrosis factor-alpha (TNF-?), and soluble TNF receptor I (sTNFRI) through a PGE2-dependent mechanism mediated by cAMP. Saliva had similar effects on lipopolysaccharide (LPS) stimulated macrophages. Conclusions Our data show that ticks utilize salivary PGE2 to subvert the ability of macrophages to secrete pro-inflammatory mediators and recruit fibroblasts to the feeding lesion, therefore inhibiting wound healing. PMID:24025197

2013-01-01

159

MicroRNAs Transfer from Human Macrophages to Hepato-Carcinoma Cells and Inhibit Proliferation  

PubMed Central

Recent research has indicated a new mode of intercellular communication facilitated by the movement of RNA between cells. There is evidence that RNA can transfer between cells in a multitude of ways, including in complex with proteins, lipids or in vesicles including apoptotic bodies and exosomes. However, there remains little understanding of the function of nucleic acid transfer between human cells. Here, we report that human macrophages transfer microRNAs (miRNAs) to hepato-carcinoma cells (HCCs) in a manner that required intercellular contact and involved gap junctions. Two specific miRNAs efficiently transferred between these cells - miR-142 and miR-223 - both endogenously expressed in macrophages and not HCCs. Transfer of these miRNAs influenced post-transcriptional regulation of proteins in HCCs, including decreased expression of reporter proteins and endogenously expressed stathmin-1 and insulin-like growth factor-1 receptor. Importantly, transfer of miRNAs from macrophages functionally inhibited proliferation of these cancerous cells. Thus, these data lead us to propose that intercellular transfer of miRNA from immune cells could serve as a new defense against unwanted cell proliferation or tumor growth. PMID:24227773

Aucher, Anne; Rudnicka, Dominika; Davis, Daniel M.

2013-01-01

160

Phenotypic and Functional Heterogeneity of Macrophages and Dendritic Cell Subsets in the Healthy and Atherosclerosis-Prone Aorta  

PubMed Central

Atherosclerosis continues to be the leading cause of cardiovascular disease. Development of atherosclerosis depends on chronic inflammation in the aorta and multiple immune cells are involved in this process. Importantly, resident macrophages and dendritic cells (DCs) are present within the healthy aorta, but the functions of these cells remain poorly characterized. Local inflammation within the aortic wall promotes the recruitment of monocytes and DC precursors to the aorta and micro-environmental factors direct the differentiation of these emigrated cells into multiple subsets of macrophages and DCs. Recent data suggest that several populations of macrophages and DCs can co-exist within the aorta. Although the functions of M1, M2, Mox, and M4 macrophages are well characterized in vitro, there is a limited set of data on the role of these populations in atherogenesis in vivo. Recent studies on the origin and the potential role of aortic DCs provide novel insights into the biology of aortic DC subsets and prospective mechanisms of the immune response in atherosclerosis. This review integrates the results of experiments analyzing heterogeneity of DCs and macrophage subsets in healthy and diseased vessels and briefly discusses the known and potential functions of these cells in atherogenesis. PMID:22457649

Butcher, Matthew J.; Galkina, Elena V.

2012-01-01

161

Macrophages and Leydig Cells in Testicular Biopsies of Azoospermic Men  

PubMed Central

A number of studies have indicated that testicular macrophages play an important role in regulating steroidogenesis of Leydig cells and maintain homeostasis within the testis. The current paper deals with macrophages (CD68 positive cells) and Leydig cells in patients with nonobstructive azoospermia (NOA). Methods employed included histological analysis on semi- and ultrathin sections, immunohistochemistry, morphometry, and hormone analysis in the blood serum. Histological analysis pointed out certain structural changes of macrophages and Leydig cells in NOA group of patients when compared to controls. In the testis interstitium, an increased presence of CD68 positive cells has been noted. Leydig cells in NOA patients displayed a kind of a mosaic picture across the same bioptic sample: both normal and damaged Leydig cells with pronounced vacuolisation and various intensity of expression of testosterone have been observed. Stereological analysis indicated a significant increase in volume density of both CD68 positive and vacuolated Leydig cells and a positive correlation between the volume densities of these cell types. The continuous gonadotropin overstimulation of Leydig cells, together with a negative paracrine action of macrophages, could result in the damage of steroidogenesis and deficit of testosterone in situ. PMID:24895614

Goluza, Trpimir; Cvetko, Jessica; Bernat, Maja Marija; Kasum, Miro; Kastelan, Zeljko; Jezek, Davor

2014-01-01

162

Endocrine, paracrine and autocrine actions of prolactin on immune cells.  

PubMed

The immune response is regulated by locally released factors, collectively referred to as cytokines. Data on the human immune system have convincingly demonstrated that the hormone prolactin (PRL), in addition to exerting its endocrine control on the immune system, acts as a cytokine in that it is released within the immune system and regulates the lymphocyte response by paracrine and autocrine mechanisms. Both lymphocyte and pituitary PRLs are under the control of immune factors. Synthesis of human PRL by lymphocytes is induced by T-cell stimuli, while increased release of PRL by the pituitary, observed in vivo after immune challenge, may be mediated by cytokines produced by monocyte-macrophages. Since hyperprolactinemia and hypoprolactinemia are both immunosuppressive, physiological levels of circulating PRL must be necessary to maintain basal immunocompetence. The effects of Cyclosporin (CsA) on IL-2 and PRL gene activation and the analysis of the intracellular signaling events downstream IL-2 and PRL receptors suggest coordinate actions of these two cytokines during T cell activation. PMID:8761011

Matera, L

1996-01-01

163

Emerging Role of Mast Cells and Macrophages in Cardiovascular and Metabolic Diseases  

PubMed Central

Mast cells are essential in allergic immune responses. Recent discoveries have revealed their direct participation in cardiovascular diseases and metabolic disorders. Although more sophisticated mechanisms are still unknown, data from animal studies suggest that mast cells act similarly to macrophages and other inflammatory cells and contribute to human diseases through cell–cell interactions and the release of proinflammatory cytokines, chemokines, and proteases to induce inflammatory cell recruitment, cell apoptosis, angiogenesis, and matrix protein remodeling. Reduced cardiovascular complications and improved metabolic symptoms in animals receiving over-the-counter antiallergy medications that stabilize mast cells open another era of mast cell biology and bring new hope to human patients suffering from these conditions. PMID:22240242

Xu, Jia-Ming

2012-01-01

164

Redirecting in vivo elicited tumor infiltrating macrophages and dendritic cells towards tumor rejection.  

PubMed

A hostile tumor microenvironment interferes with the development and function of the adaptive immune response. Here we report the mechanisms by which large numbers of tumor-infiltrating macrophages and dendritic cells (DC) can be redirected to become potent effectors and activators of the innate and adaptive immunity, respectively. We use adenoviral delivery of the CCL16 chemokine to promote accumulation of macrophages and DC at the site of preestablished tumor nodules, combined with the Toll-like receptor 9 ligand CpG and with anti-interleukin-10 receptor antibody. CpG plus anti-interleukin-10 receptor antibody promptly switched infiltrating macrophages infiltrate from M2 to M1 and triggered innate response debulking large tumors within 16 hours. Tumor-infiltrating DC matured and migrated in parallel with the onset of the innate response, allowing the triggering of adaptive immunity before the diffuse hemorrhagic necrosis halted the communication between tumor and draining lymph nodes. Treatment of B6>CXB6 chimeras implanted with BALB/c tumors with the above combination induced an efficient innate response but not CTL-mediated tumor lysis. In these mice, tumor rejection did not exceed 25%, similarly to that observed in CCR7-null mice that have DC unable to prime an adaptive response. The requirement of CD4 help was shown in CD40-KO, as well as in mice depleted of CD4 T cells, during the priming rather than the effector phase. Our data describe the critical requirements for the immunologic rejection of large tumors: a hemorrhagic necrosis initiated by activated M1 macrophages and a concomitant DC migration to draining lymph nodes for subsequent CTL priming and clearing of any tumor remnants. PMID:15833879

Guiducci, Cristiana; Vicari, Alain P; Sangaletti, Sabina; Trinchieri, Giorgio; Colombo, Mario P

2005-04-15

165

Single-cell technologies for monitoring interactions between immune cells  

E-print Network

Immune cells participate in dynamic cellular interactions that play a critical role in the defense against pathogens and the destruction of malignant cells. The vast heterogeneity of immune cells motivates the study of ...

Yamanaka, Yvonne J. (Yvonne Joy)

2014-01-01

166

Mannose-binding lectin is required for the effective clearance of apoptotic cells by adipose tissue macrophages during obesity.  

PubMed

Obesity is accompanied by the presence of chronic low-grade inflammation manifested by infiltration of macrophages into adipose tissue. Mannose-binding lectin (MBL), a soluble mediator of innate immunity, promotes phagocytosis and alters macrophage function. To assess the function of MBL in the development of obesity, we studied wild-type and MBL(-/-) mice rendered obese using a high-fat diet (HFD). Whereas no gross morphological differences were observed in liver, an HFD provoked distinct changes in the adipose tissue morphology of MBL(-/-) mice. In parallel with increased adipocyte size, MBL(-/-) mice displayed an increased influx of macrophages into adipose tissue. Macrophages were polarized toward an alternatively activated phenotype known to modulate apoptotic cell clearance. MBL deficiency also significantly increased the number of apoptotic cells in adipose tissue. Consistent with these observations, recombinant MBL enhanced phagocytic capacity of the stromal vascular fraction isolated from adipose tissue and modulated uptake of apoptotic adipocytes by macrophages. Despite changes in macrophage abundance and polarity, the absence of MBL did not affect systemic insulin resistance. Finally, in humans, lower levels of circulating MBL were accompanied by enhanced macrophage influx in subcutaneous adipose tissue. We propose a novel role for MBL in the recognition and clearance of apoptotic adipocytes during obesity. PMID:25008177

Stienstra, Rinke; Dijk, Wieneke; van Beek, Lianne; Jansen, Henry; Heemskerk, Mattijs; Houtkooper, Riekelt H; Denis, Simone; van Harmelen, Vanessa; Willems van Dijk, Ko; Tack, Cees J; Kersten, Sander

2014-12-01

167

Characterisation of renal immune cell infiltrates in children with nephrotic syndrome  

Microsoft Academic Search

There is increasing evidence that not only T cells but also B cells may play an important role in the pathogenesis of idiopathic\\u000a nephrotic syndrome (NS). We have evaluated the infiltrating immune cells found in renal biopsies from 38 children with NS\\u000a using immunohistochemistry techniques involving antibodies against T cells (CD3, CD4, CD8, FoxP3), B cells (CD20), macrophages\\u000a (CD68) and

Kerstin Benz; Maike Büttner; Katalin Dittrich; Valentina Campean; Jörg Dötsch; Kerstin Amann

2010-01-01

168

Memory-T-cell-derived interferon-? instructs potent innate cell activation for protective immunity.  

PubMed

Cells of the innate immune system are essential for host defenses against primary microbial pathogen infections, yet their involvement in effective memory responses of vaccinated individuals has been poorly investigated. Here we show that memory T cells instruct innate cells to become potent effector cells in a systemic and a mucosal model of infection. Memory T cells controlled phagocyte, dendritic cell, and NK or NK T cell mobilization and induction of a strong program of differentiation, which included their expression of effector cytokines and microbicidal pathways, all of which were delayed in nonvaccinated hosts. Disruption of IFN-? signaling in Ly6C+ monocytes, dendritic cells, and macrophages impaired these processes and the control of pathogen growth. These results reveal how memory T cells, through rapid secretion of IFN-?, orchestrate extensive modifications of host innate immune responses that are essential for effective protection of vaccinated hosts. PMID:24931122

Soudja, Saïdi M'Homa; Chandrabos, Ceena; Yakob, Ernest; Veenstra, Mike; Palliser, Deborah; Lauvau, Grégoire

2014-06-19

169

Recognition of tumor cells by Dectin-1 orchestrates innate immune cells for anti-tumor responses  

PubMed Central

The eradication of tumor cells requires communication to and signaling by cells of the immune system. Natural killer (NK) cells are essential tumor-killing effector cells of the innate immune system; however, little is known about whether or how other immune cells recognize tumor cells to assist NK cells. Here, we show that the innate immune receptor Dectin-1 expressed on dendritic cells and macrophages is critical to NK-mediated killing of tumor cells that express N-glycan structures at high levels. Receptor recognition of these tumor cells causes the activation of the IRF5 transcription factor and downstream gene induction for the full-blown tumoricidal activity of NK cells. Consistent with this, we show exacerbated in vivo tumor growth in mice genetically deficient in either Dectin-1 or IRF5. The critical contribution of Dectin-1 in the recognition of and signaling by tumor cells may offer new insight into the anti-tumor immune system with therapeutic implications. DOI: http://dx.doi.org/10.7554/eLife.04177.001 PMID:25149452

Chiba, Shiho; Ikushima, Hiroaki; Ueki, Hiroshi; Yanai, Hideyuki; Kimura, Yoshitaka; Hangai, Sho; Nishio, Junko; Negishi, Hideo; Tamura, Tomohiko; Saijo, Shinobu; Iwakura, Yoichiro; Taniguchi, Tadatsugu

2014-01-01

170

Recognition of tumor cells by Dectin-1 orchestrates innate immune cells for anti-tumor responses.  

PubMed

The eradication of tumor cells requires communication to and signaling by cells of the immune system. Natural killer (NK) cells are essential tumor-killing effector cells of the innate immune system; however, little is known about whether or how other immune cells recognize tumor cells to assist NK cells. Here, we show that the innate immune receptor Dectin-1 expressed on dendritic cells and macrophages is critical to NK-mediated killing of tumor cells that express N-glycan structures at high levels. Receptor recognition of these tumor cells causes the activation of the IRF5 transcription factor and downstream gene induction for the full-blown tumoricidal activity of NK cells. Consistent with this, we show exacerbated in vivo tumor growth in mice genetically deficient in either Dectin-1 or IRF5. The critical contribution of Dectin-1 in the recognition of and signaling by tumor cells may offer new insight into the anti-tumor immune system with therapeutic implications. PMID:25149452

Chiba, Shiho; Ikushima, Hiroaki; Ueki, Hiroshi; Yanai, Hideyuki; Kimura, Yoshitaka; Hangai, Sho; Nishio, Junko; Negishi, Hideo; Tamura, Tomohiko; Saijo, Shinobu; Iwakura, Yoichiro; Taniguchi, Tadatsugu

2014-01-01

171

Phagocyte sabotage: disruption of macrophage signalling by bacterial pathogens  

Microsoft Academic Search

Macrophages function at the front line of immune defences against incoming pathogens. But the ability of macrophages to internalize bacteria, migrate, recruit other immune cells to the site of infection and influence the nature of the immune response can provide unintended benefits for bacterial pathogens that are able to subvert or co-opt these normally effective defences. This review highlights recent

Carrie M. Rosenberger; B. Brett Finlay

2003-01-01

172

Lamina propria macrophages and dendritic cells differentially induce regulatory and interleukin 17–producing T cell responses  

Microsoft Academic Search

The intestinal immune system must elicit robust immunity against harmful pathogens but must also restrain immune responses directed against commensal microbes and dietary antigens. The mechanisms that maintain this dichotomy are poorly understood. Here we describe a population of CD11b+F4\\/80+CD11c? macrophages in the lamina propria that expressed several anti-inflammatory molecules, including interleukin 10 (IL-10), but little or no proinflammatory cytokines,

Timothy L Denning; Yi-chong Wang; Seema R Patel; Ifor R Williams; Bali Pulendran

2007-01-01

173

Dendritic Cells and Humoral Immunity in Humans  

PubMed Central

Summary Dendritic cells (DCs) orchestrate the innate and adaptive immune systems to induce tolerance and immunity. DC plasticity and subsets are prominent determinants in the regulation of immune responses. Our recent studies suggest that humoral and cellular immunity is regulated by different myeloid DC subsets with distinct intrinsic properties in humans. While antibody response is preferentially mediated by CD14+ dermal DCs, cytotoxic T cell response is preferentially mediated by Langerhans cells (LCs). Thus, mechanisms whereby DCs induce humoral and cellular immunity appear to be fundamentally distinct. In this review, we will focus on the role of DCs in the development of humoral immunity. We will also discuss the mechanisms whereby DCs induce CD4+ T cells associated with the help of B cell response, including T follicular helper (Tfh) cells, and why human LCs lack this ability. PMID:20309010

Ueno, Hideki; Schmitt, Nathalie; Palucka, A. Karolina; Banchereau, Jacques

2010-01-01

174

Induction of Rapid Cell Death by an Environmental Isolate of Legionella pneumophila in Mouse Macrophages  

PubMed Central

Legionella pneumophila, the etiological agent for Legionnaires' disease, is ubiquitous in the aqueous environment, where it replicates as an intracellular parasite of free-living protozoa. Our understanding of L. pneumophila pathogenicity is obtained mostly from study of derivatives of several clinical isolates, which employ almost identical virulent determinants to exploit host functions. To determine whether environmental L. pneumophila isolates interact similarly with the model host systems, we analyzed intracellular replication of several recently isolated such strains and found that these strains cannot productively grow in bone marrow-derived macrophages of A/J mice, which are permissive for all examined laboratory strains. By focusing on one strain called LPE509, we found that its deficiency in intracellular replication in primary A/J macrophages is not caused by the lack of important pathogenic determinants because this strain replicates proficiently in two protozoan hosts and the human macrophage U937 cell. We also found that in the early phase of infection, the trafficking of this strain in A/J macrophages is similar to that of JR32, a derivative of strain Philadelphia 1. Furthermore, infection of these cells by LPE509 caused extensive cell death in a process that requires the Dot/Icm type IV secretion system. Finally, we showed that the cell death is caused neither by the activation of the NAIP5/NLRC4 inflammasome nor by the recently described caspase 11-dependent pathway. Our results revealed that some environmental L. pneumophila strains are unable to overcome the defense conferred by primary macrophages from mice known to be permissive for laboratory L. pneumophila strains. These results also suggest the existence of a host immune surveillance mechanism differing from those currently known in responding to L. pneumophila infection. PMID:23753633

Tao, Lili; Zhu, Wenhan; Hu, Bi-Jie

2013-01-01

175

``Backpack'' Functionalized Living Immune Cells  

NASA Astrophysics Data System (ADS)

We demonstrate that functional polymeric ``backpacks'' built from polyelectrolyte multilayers (PEMs) can be attached to a fraction of the surface area of living, individual lymphocytes. Backpacks containing fluorescent polymers, superparamagnetic nanoparticles, and commercially available quantum dots have been attached to B and T-cells, which may be spatially manipulated using a magnetic field. Since the backpack does not occlude the entire cellular surface from the environment, this technique allows functional synthetic payloads to be attached to a cell that is free to perform its native functions, thereby synergistically utilizing both biological and synthetic functionalities. For instance, we have shown that backpack-modified T-cells are able to migrate on surfaces for several hours following backpack attachment. Possible payloads within the PEM backpack include drugs, vaccine antigens, thermally responsive polymers, nanoparticles, and imaging agents. We will discuss how this approach has broad potential for applications in bioimaging, single-cell functionalization, immune system and tissue engineering, and cell-based therapeutics where cell-environment interactions are critical.

Swiston, Albert; Um, Soong Ho; Irvine, Darrell; Cohen, Robert; Rubner, Michael

2009-03-01

176

Expression of macrophage migration inhibitory factor by neuroblastoma leads to the inhibition of antitumor T cell reactivity in vivo.  

PubMed

Neuroblastomas and many other solid tumors produce high amounts of macrophage migration inhibitory factor (MIF), which appears to play a role in tumor progression. We found that MIF expression in neuroblastoma inhibits T cell proliferation in vitro, raising the possibility that MIF promotes tumorigenesis, in part, by suppressing antitumor immunity. To examine whether tumor-derived MIF leads to suppression of T cell immunity in vivo, we generated MIF-deficient neuroblastoma cell lines using short hairpin small interfering RNAs (siRNA). The MIF knockdown (MIFKD) AGN2a neuroblastoma cells were more effectively rejected in immune-competent mice than control siRNA-transduced or wild-type AGN2a. However, the increased rejection of MIFKD AGN2a was not observed in T cell-depleted mice. MIFKD tumors had increased infiltration of CD8(+) and CD4(+) T cells, as well as increased numbers of macrophages, dendritic cells, and B cells. Immunization with MIFKD AGN2a cells significantly increased protection against tumor challenge as compared with immunization with wild-type AGN2a, and the increased protection correlated with elevated frequencies of tumor-reactive CD8(+) T cells in the lymphoid tissue of treated animals. Increased numbers of infiltrating tumor-reactive CD8(+) T cells were also observed at the site of tumor vaccination. In vitro, treatment of AGN2a-derived culture supernatants with neutralizing MIF-specific Ab failed to reverse T cell suppressive activity, suggesting that MIF is not directly responsible for the immune suppression in vivo. This supports a model whereby MIF expression in neuroblastoma initiates a pathway that leads to the suppression of T cell immunity in vivo. PMID:18641325

Zhou, Qiang; Yan, Xiaocai; Gershan, Jill; Orentas, Rimas J; Johnson, Bryon D

2008-08-01

177

Telomere Shortening and Oxidative Stress in Aged Macrophages Results in Impaired STAT5a Phosphorylation1  

Microsoft Academic Search

Macrophages are an essential component of both innate and adaptive immunity, and altered function of these cells with aging may play a key role in immunosenescence. To determine the effect of aging on macrophages, we produced bone marrow-derived macrophages in vitro. In these conditions, we analyzed the effect of aging on macrophages without the influence of other cell types that

Carlos Sebastian; Carmen Herrero; Maria Serra; Jorge Lloberas; María A. Blasco; Antonio Celada

178

MyD88 signaling pathway is involved in renal fibrosis by favoring a TH2 immune response and activating alternative M2 macrophages.  

PubMed

Inflammation contributes to the pathogenesis of chronic kidney disease (CKD). Molecules released by the inflamed injured tissue can activate toll-like receptors (TLRs), thereby modulating macrophage and CD4(+) T-cell activity. We propose that in renal fibrogenesis, M2 macrophages are recruited and activated in a T helper subset 2 cell (T(H)2)-prone inflammatory milieu in a MyD88-dependent manner. Mice submitted to unilateral ureteral ligation (UUO) demonstrated an increase in macrophage infiltration with collagen deposition after 7 d. Conversely, TLR2, TLR4 and MyD88 knockout (KO) mice had an improved renal function together with diminished T(H)2 cytokine production and decreased fibrosis formation. Moreover, TLR2, TLR4 and MyD88 KO animals exhibited less M2 macrophage infiltration, namely interleukin (IL)-10(+) and CD206(+) CD11b(high) cells, at 7 d after surgery. We evaluated the role of a T(H)2 cytokine in this context, and observed that the absence of IL-4 was associated with better renal function, decreased IL-13 and TGF-? levels, reduced arginase activity and a decrease in fibrosis formation when compared with IL-12 KO and wild-type (WT) animals. Indeed, the better renal outcomes and the decreased fibrosis formation were restricted to the deficiency of IL-4 in the hematopoietic compartment. Finally, macrophage depletion, rather than the absence of T cells, led to reduced lesions of the glomerular filtration barrier and decreased collagen deposition. These results provide evidence that future therapeutic strategies against renal fibrosis should be accompanied by the modulation of the M1:M2 and T(H)1:T(H)2 balance, as T(H)2 and M2 cells are predictive of fibrosis toward mechanisms that are sensed by innate immune response and triggered in a MyD88-dependent pathway. PMID:22777483

Braga, Tarcio Teodoro; Correa-Costa, Matheus; Guise, Yuri Felipe Souza; Castoldi, Angela; de Oliveira, Cassiano Donizetti; Hyane, Meire Ioshie; Cenedeze, Marcos Antonio; Teixeira, Simone Aparecida; Muscara, Marcelo Nicolas; Perez, Katia Regina; Cuccovia, Iolanda Midea; Pacheco-Silva, Alvaro; Gonçalves, Giselle Martins; Camara, Niels Olsen Saraiva

2012-01-01

179

Tissue macrophages: "satellite cells" for growing collateral vessels? A hypothesis.  

PubMed

It has been demonstrated in several studies that collateral growth is associated with accumulation of macrophages around proliferating vessel. Macrophages are known to secrete vascular growth factors and metalloproteinases. Both are necessary for the development of a proper vasculature. Recent studies suggest that certain subpopulations of macrophages are also capable of transdifferentiating into vascular cells. There are good reasons to assume that shear force rises dramatically in preexisting arteriolar shunts after occlusion of the main supplying vessel. Based upon these two findings it was hypothesized that high shear forces lead to homing of circulating monocytes to the growing collateral artery. The majority of studies, however, indicate that monocytes home under low shear force conditions. Our own observations in monocyte depleted animals suggest that proliferation and transdifferentiation of tissue macrophages occurs locally in growing collateral vessels and is independent of circulating cells. We thus propose that local proliferation and transdifferentiation of tissue macrophages rather than homing of circulating monocytes play a major role in arteriogenesis. PMID:14660083

Ito, Wulf D; Khmelevski, Eugen

2003-01-01

180

Targeted Immune Cells Shrink Tumors in Mice  

Cancer.gov

Researchers have generated altered immune cells that are able to shrink, and in some cases eradicate, large tumors in mice. The immune cells target mesothelin, a protein that is highly expressed, or translated in large amounts from the mesothelin gene, on the surface of several types of cancer cells.

181

Two-photon intravital imaging of lungs during anthrax infection reveals long-lasting macrophage-dendritic cell contacts.  

PubMed

The dynamics of the lung immune system at the microscopic level are largely unknown because of inefficient methods of restraining chest motion during image acquisition. In this study, we developed an improved intravital method for two-photon lung imaging uniquely based on a posteriori parenchymal tissue motion correction. We took advantage of the alveolar collagen pattern given by the second harmonic generation signal as a reference for frame registration. We describe here for the first time a detailed dynamic account of two major lung immune cell populations, alveolar macrophages and CD11b-positive dendritic cells, during homeostasis and infection by spores of Bacillus anthracis, the agent of anthrax. We show that after alveolar macrophages capture spores, CD11b-positive dendritic cells come in prolonged contact with infected macrophages. Dendritic cells are known to carry spores to the draining lymph nodes and elicit the immune response in pulmonary anthrax. The intimate and long-lasting contacts between these two lines of defense may therefore coordinate immune responses in the lung through an immunological synapse-like process. PMID:24478099

Fiole, Daniel; Deman, Pierre; Trescos, Yannick; Mayol, Jean-François; Mathieu, Jacques; Vial, Jean-Claude; Douady, Julien; Tournier, Jean-Nicolas

2014-02-01

182

Two-Photon Intravital Imaging of Lungs during Anthrax Infection Reveals Long-Lasting Macrophage-Dendritic Cell Contacts  

PubMed Central

The dynamics of the lung immune system at the microscopic level are largely unknown because of inefficient methods of restraining chest motion during image acquisition. In this study, we developed an improved intravital method for two-photon lung imaging uniquely based on a posteriori parenchymal tissue motion correction. We took advantage of the alveolar collagen pattern given by the second harmonic generation signal as a reference for frame registration. We describe here for the first time a detailed dynamic account of two major lung immune cell populations, alveolar macrophages and CD11b-positive dendritic cells, during homeostasis and infection by spores of Bacillus anthracis, the agent of anthrax. We show that after alveolar macrophages capture spores, CD11b-positive dendritic cells come in prolonged contact with infected macrophages. Dendritic cells are known to carry spores to the draining lymph nodes and elicit the immune response in pulmonary anthrax. The intimate and long-lasting contacts between these two lines of defense may therefore coordinate immune responses in the lung through an immunological synapse-like process. PMID:24478099

Fiole, Daniel; Deman, Pierre; Trescos, Yannick; Mayol, Jean-Francois; Mathieu, Jacques; Vial, Jean-Claude; Douady, Julien

2014-01-01

183

A novel lipopolysaccharide-binding protein (LBP) gene from sweetfish Plecoglossus altivelis: molecular characterization and its role in the immune response of monocytes/macrophages.  

PubMed

Lipopolysaccharide-binding protein (LBP) belongs to the lipid transfer/LBP (LT-LBP) family, and plays a crucial role in the recognition of bacterial components that modulate cellular signals in phagocytic cells. Although several LBPs have been identified in teleosts, the effects of LBP homologs on teleost phagocytic cells are still obscure. Here, we report the cloning a novel full-length cDNA sequence of LBP-like protein (paLBP) gene from sweetfish, Plecoglossus altivelis. The paLBP cDNA encoded a 464 aa polypeptide, which was closest to that of rainbow smelt (Osmerus mordax). paLBP mRNA was detected mainly in the spleen, liver, and head kidney and levels dramatically increased in various tissues after Listonella anguillarum infection. In contrast to mammalian studies, paLBP mRNA could also be detected in sweetfish monocytes/macrophages. Recombinant paLBP showed LPS-binding activity and Western blot results revealed a significant increase of paLBP in the supernatant of sweetfish monocytes/macrophages challenged with L. anguillarum. Moreover, paLBP neutralization led to up-regulation of IL-1? and TNF-? mRNA as well as respiratory burst activity in sweetfish monocytes/macrophages in response to L. anguillarum or LPS challenge. Therefore, these results suggest that paLBP is an inducible acute-phase protein mediating the immune response of sweetfish monocytes/macrophages upon bacterial challenge. PMID:24594008

Lu, Xin-Jiang; Chu, Chang-Qing; Chen, Qiang; Chen, Jiong

2014-05-01

184

Glycosylation in immune cell trafficking  

PubMed Central

Summary Leukocyte recruitment encompasses cell adhesion and activation steps that enable circulating leukocytes to roll, arrest, and firmly adhere on the endothelial surface before they extravasate into distinct tissue locations. This complex sequence of events relies on adhesive interactions between surface structures on leukocytes and endothelial cells and also on signals generated during the cell-cell contacts. Cell surface glycans play a crucial role in leukocyte recruitment. Several glycosyltransferases such as ?1,3 fucosyltransferases, ?2,3 sialyltransferases, core 2 N-acetylglucosaminlytransferases, ?1,4 galactosyltransferases and polypeptide N-acetylgalactosaminyltransferases have been implicated in the generation of functional selectin ligands that mediate leukocyte rolling via binding to selectins. Recent evidence also suggests a role of ?2,3 sialylated carbohydrate determinants in triggering chemokine-mediated leukocyte arrest and influencing ?1 integrin function. Additional mechanisms by galectin- and siglec-dependent processes contribute to the growing number of reports emphasizing the significant role of glycans for the successful recruitment of leukocytes into tissues. Advancing the knowledge on glycan function into appropriate pathology models is likely to suggest interesting new therapeutic strategies in the treatment of immune- and inflammation-mediated diseases. PMID:19594631

Sperandio, Markus; Gleissner, Christian A.; Ley, Klaus

2009-01-01

185

Crystallization of free cholesterol in model macrophage foam cells.  

PubMed

-The present study examined free cholesterol (FC) crystallization in macrophage foam cells. Model foam cells (J774 or mouse peritoneal macrophages [MPMs]) were incubated with acetylated low density lipoprotein and FC/phospholipid dispersions for 48 hours, resulting in the deposition of large stores of cytoplasmic cholesteryl esters (CEs). The model foam cells were then incubated for up to 5 days with an acyl-coenzyme A:cholesterol acyltransferase (ACAT) inhibitor (CP-113,818) in the absence of an extracellular FC acceptor to allow intracellular accumulation of FC. FC crystals of various shapes and sizes formed in the MPMs but not in the J774 macrophages. Examination of the MPM monolayers by microscopy indicated that the crystals were externalized rapidly after formation and thereafter continued to increase in size. Incubating J774 macrophages with 8-(4-chlorophenylthio)adenosine 3':5'-cyclic monophosphate (CPT-cAMP) in addition to CP-113,818 caused FC crystal formation as a consequence of CPT-cAMP stimulation of CE hydrolysis and inhibition of cell growth. In addition, 2 separate cholesterol phases (liquid-crystalline and cholesterol monohydrate) in the plane of the membrane bilayer were detected after 31 hours of ACAT inhibition by the use of small-angle x-ray diffraction of J774 macrophage foam cells treated with CPT-cAMP. Other compounds reported to inhibit ACAT, namely progesterone (20 microgram/mL) and N-acetyl-D-sphingosine (c(2)-ceramide, 10 microgram/mL), induced cellular toxicity in J774 macrophage foam cells and FC crystallization when coincubated with CPT-cAMP. Addition of the extracellular FC acceptors apolipoproteins (apo) E and A-I (50 microgram/mL) reduced FC crystal formation. In MPMs, lower cell density and frequent changes of medium were conducive to crystal formation. This may be due to "dilution" of apoE secreted by the MPMs and is consistent with our observation that the addition of exogenous apoE or apoA-I inhibits FC crystal formation in J774 macrophage foam cells cotreated with CP-113,818 plus CPT-cAMP. These data demonstrate that FC crystals can form from the hydrolysis of cytoplasmic stores of CEs in model foam cells. FC crystal formation can be modulated by the addition of extracellular FC acceptors or by affecting the cellular rate of CE hydrolysis. This process may contribute to the formation of FC crystals in atherosclerotic plaques. PMID:10446067

Kellner-Weibel, G; Yancey, P G; Jerome, W G; Walser, T; Mason, R P; Phillips, M C; Rothblat, G H

1999-08-01

186

CXCR5+ T helper cells mediate protective immunity against tuberculosis  

PubMed Central

One third of the world’s population is infected with Mycobacterium tuberculosis (Mtb). Although most infected people remain asymptomatic, they have a 10% lifetime risk of developing active tuberculosis (TB). Thus, the current challenge is to identify immune parameters that distinguish individuals with latent TB from those with active TB. Using human and experimental models of Mtb infection, we demonstrated that organized ectopic lymphoid structures containing CXCR5+ T cells were present in Mtb-infected lungs. In addition, we found that in experimental Mtb infection models, the presence of CXCR5+ T cells within ectopic lymphoid structures was associated with immune control. Furthermore, in a mouse model of Mtb infection, we showed that activated CD4+CXCR5+ T cells accumulated in Mtb-infected lungs and produced proinflammatory cytokines. Mice deficient in Cxcr5 had increased susceptibility to TB due to defective T cell localization within the lung parenchyma. We demonstrated that CXCR5 expression in T cells mediated correct T cell localization within TB granulomas, promoted efficient macrophage activation, protected against Mtb infection, and facilitated lymphoid follicle formation. These data demonstrate that CD4+CXCR5+ T cells play a protective role in the immune response against TB and highlight their potential use for future TB vaccine design and therapy. PMID:23281399

Slight, Samantha R.; Rangel-Moreno, Javier; Gopal, Radha; Lin, Yinyao; Fallert Junecko, Beth A.; Mehra, Smriti; Selman, Moises; Becerril-Villanueva, Enrique; Baquera-Heredia, Javier; Pavon, Lenin; Kaushal, Deepak; Reinhart, Todd A.; Randall, Troy D.; Khader, Shabaana A.

2013-01-01

187

Mathematical model of macrophage-facilitated breast cancer cells invasion.  

PubMed

Mortality from breast cancer stems from its tendency to invade into surrounding tissues and organs. Experiments have shown that this metastatic process is facilitated by macrophages in a short-ranged chemical signalling loop. Macrophages secrete epidermal growth factor, EGF, and respond to the colony stimulating factor 1, CSF-1. Tumor cells secrete CSF-1 and respond to EGF. In this way, the cells coordinate aggregation and cooperative migration. Here we investigate this process in a model for in vitro interactions using two distinct but related mathematical approaches. In the first, we analyze and simulate a set of partial differential equations to determine conditions for aggregation. In the second, we use a cell-based discrete 3D simulation to follow the fates and motion of individual cells during aggregation. Linear stability analysis of the PDE model reveals that decreasing the chemical secretion, chemotaxis coefficients or density of cells or increasing the chemical degradation in the model could eliminate the spontaneous aggregation of cells. Simulations with the discrete model show that the ratio between tumor cells and macrophages in aggregates increases when the EGF secretion parameter is increased. The results also show how CSF-1/CSF-1R autocrine signalling in tumor cells affects the ratio between the two cell types. Comparing the continuum results with simulations of a discrete cell-based model, we find good qualitative agreement. PMID:24810842

Knútsdóttir, Hildur; Pálsson, Eirikur; Edelstein-Keshet, Leah

2014-09-21

188

TLR4 Activation Under Lipotoxic Conditions Leads to Synergistic Macrophage Cell Death Through a TRIF-Dependent Pathway1  

PubMed Central

Macrophage dysfunction in obesity and diabetes may predispose to the development of diabetic complications such as infection and impaired healing after tissue damage. Saturated fatty acids, such as palmitate, are present at elevated concentrations in the plasma of patients with metabolic disease and may contribute to the pathogenesis of diabetes and its sequelae. To examine the effect of lipid excess on macrophage inflammatory function, we determined the influence of palmitate on LPS-mediated responses in peritoneal macrophages. Palmitate and LPS led to a profound synergistic cell death response in both primary and RAW 264.7 macrophages. The cell death had features of apoptosis and necrosis and was not dependent on ER stress, ceramide generation, or reactive oxygen species production. Instead, we uncovered a macrophage death pathway that required TLR4 signaling via TRIF, but was independent of NF-?B, MAP kinases, and IRF3. A significant decrease in macrophage lysosomal content was observed early in the death pathway, with evidence of lysosomal membrane damage occurring later in the death response. Over-expression of the transcription factor TFEB, which induces a lysosomal biogenic program, rescued the lysosomal phenotype and improved viability in palmitate and LPS treated cells. Our findings provide new evidence for crosstalk between lipid metabolism and the innate immune response that converges on the lysosome. PMID:23275600

Schilling, Joel D.; Machkovech, Heather M.; He, Li; Diwan, Abhinav; Schaffer, Jean E.

2012-01-01

189

IL-27 affects helper T cell responses via regulation of PGE2 production by macrophages.  

PubMed

IL-27 is a heterodimeric cytokine that regulates both innate and adaptive immunity. The immunosuppressive effect of IL-27 largely depends on induction of IL-10-producing Tr1 cells. To date, however, effects of IL-27 on regulation of immune responses via mediators other than cytokines remain poorly understood. To address this issue, we examined immunoregulatory effects of conditional medium of bone marrow-derived macrophages (BMDMs) from WSX-1 (IL-27R?)-deficient mice and found enhanced IFN-? and IL-17A secretion by CD4(+) T cells as compared with that of control BMDMs. We then found that PGE2 production and COX-2 expression by BMDMs from WSX-1-deficient mice was increased compared to control macrophages in response to LPS. The enhanced production of IFN-? and IL-17A was abolished by EP2 and EP4 antagonists, demonstrating PGE2 was responsible for enhanced cytokine production. Murine WSX-1-expressing Raw264.7 cells (mWSX-1-Raw264.7) showed phosphorylation of both STAT1 and STAT3 in response to IL-27 and produced less amounts of PGE2 and COX-2 compared to parental RAW264.7 cells. STAT1 knockdown in parental RAW264.7 cells and STAT1-deficiency in BMDMs showed higher COX-2 expression than their respective control cells. Collectively, our result indicated that IL-27/WSX-1 regulated PGE2 secretion via STAT1-COX-2 pathway in macrophages and affected helper T cell response in a PGE2-mediated fashion. PMID:25088998

Sato, Yayoi; Hara, Hiromitsu; Okuno, Toshiaki; Ozaki, Naoko; Suzuki, Shinobu; Yokomizo, Takehiko; Kaisho, Tsuneyasu; Yoshida, Hiroki

2014-08-22

190

IDENTIFICATION OF MACROPHAGE MIGRATION INHIBITORY FACTOR (MIF) IN HUMAN VASCULAR ENOTHELIAL CELLS AND ITS INDUCTION BY LIPOPOLYSACCHARIDE  

Microsoft Academic Search

Cytokines play an important role in inflammation and immunity. In this study, the authors examined expression of macrophage migration inhibitory factor (MIF) in vascular endothelial cells, using human umbilical vein endothelial cells (HUVEC), by reverse transcription-polymerase chain reaction (RT-PCR)\\/Southern blot, Western blot analysis, and immunohistochemistry. The RT\\/PCR\\/Southern blot showed that MIF mRNA was exceedingly upregulated by the stimulation of lipopolysaccharide

Jun Nishihira; Yoshikazu Koyama; Yuka Mizue

1998-01-01

191

Cigarette smoke-induced iBALT mediates macrophage activation in a B cell-dependent manner in COPD.  

PubMed

Chronic obstructive pulmonary disease (COPD) is characterized by a progressive decline in lung function, caused by exposure to exogenous particles, mainly cigarette smoke (CS). COPD is initiated and perpetuated by an abnormal CS-induced inflammatory response of the lungs, involving both innate and adaptive immunity. Specifically, B cells organized in iBALT structures and macrophages accumulate in the lungs and contribute to CS-induced emphysema, but the mechanisms thereof remain unclear. Here, we demonstrate that B cell-deficient mice are significantly protected against CS-induced emphysema. Chronic CS exposure led to an increased size and number of iBALT structures, and increased lung compliance and mean linear chord length in wild-type (WT) but not in B cell-deficient mice. The increased accumulation of lung resident macrophages around iBALT and in emphysematous alveolar areas in CS-exposed WT mice coincided with upregulated MMP12 expression. In vitro coculture experiments using B cells and macrophages demonstrated that B cell-derived IL-10 drives macrophage activation and MMP12 upregulation, which could be inhibited by an anti-IL-10 antibody. In summary, B cell function in iBALT formation seems necessary for macrophage activation and tissue destruction in CS-induced emphysema and possibly provides a new target for therapeutic intervention in COPD. PMID:25128521

John-Schuster, Gerrit; Hager, Katrin; Conlon, Thomas M; Irmler, Martin; Beckers, Johannes; Eickelberg, Oliver; Yildirim, Ali Önder

2014-11-01

192

Innate Immunity, Decidual Cells, and Preeclampsia  

PubMed Central

Preeclampsia (PE) manifested by hypertension and proteinuria complicates 3% to 8% of pregnancies and is a leading cause of fetal–maternal morbidity and mortality worldwide. It may lead to intrauterine growth restriction, preterm delivery, and long-term sequelae in women and fetuses, and consequently cause socioeconomic burden to the affected families and society as a whole. Balanced immune responses are required for the maintenance of successful pregnancy. Although not a focus of most studies, decidual cells, the major resident cell type at the fetal–maternal interface, have been shown to modulate the local immune balance by interacting with other cell types, such as bone marrow derived-immune cells, endothelial cells, and invading extravillous trophoblasts. Accumulating evidence suggests that an imbalanced innate immunity, facilitated by decidual cells, plays an important role in the pathogenesis of PE. Thus, this review will discuss the role of innate immunity and the potential contribution of decidual cells in the pathogenesis of PE. PMID:22814099

Yeh, Chang-Ching; Chao, Kuan-Chong

2013-01-01

193

Sessile alveolar macrophages modulate immunity through connexin 43-based epithelial communication  

PubMed Central

Tissue-resident macrophages of barrier organs constitute the first line of defense against pathogens at the systemic interface with the ambient environment. In lung, resident alveolar macrophages (AMs) provide sentinel function against inhaled pathogens1. Bacterial constituents ligate toll-like receptors (TLRs) on AMs2, causing AMs to secrete proinflammatory cytokines3 that activate alveolar epithelial receptors4, leading to recruitment of neutrophils that engulf pathogens5,6. However, since the AM-induced immune response could itself cause tissue injury, it is unclear how AMs modulate the response to prevent injury. Here, through real-time alveolar imaging in situ, we show that a subset of AMs attached to the alveolar wall, formed connexin 43 (Cx43)-containing gap junctional channels (GJCs) with the epithelium. During lipopolysaccharide (LPS)-induced inflammation, the AMs remained alveolus-attached and sessile, and they established intercommunication through synchronized Ca2+ waves, using the epithelium as the conducting pathway. The intercommunication was immunosuppressive, involving Ca2+ dependent activation of Akt, since AM-specific knockout of Cx43 enhanced alveolar neutrophil recruitment and secretion of proinflammatory cytokines in the bronchoalveolar lavage (BAL). The picture emerges of a novel immunomodulatory process in which a subset of alveolus-attached AMs intercommunicates immunosuppressive signals to reduce endotoxin-induced lung inflammation. PMID:24463523

Westphalen, Kristin; Gusarova, Galina A.; Islam, Mohammad N.; Subramanian, Manikandan; Cohen, Taylor S.; Prince, Alice S.; Bhattacharya, Jahar

2014-01-01

194

Characterization of the immune cell repertoire in the normal fallopian tube.  

PubMed

Recent studies implicating the fallopian tube as the site of putative precursors of ovarian serous carcinoma, and the hypothesis that injury, inflammation, and repair of the ovarian surface epithelium at the time of ovulation, may be contributing factors to ovarian carcinogenesis, prompted us to undertake a comprehensive analysis of the immune cells in the normal fallopian tube. Accordingly, the aim of this study was to provide a baseline for future studies exploring the relationship of inflammation with the early events of ovarian carcinogenesis by characterizing the immune cell repertoire in 13 normal human fallopian tubes, combining digital microscopy of immunostained slides and flow cytometry of fresh single-cell suspensions, with a panel of markers that identify the most important adaptive and innate immune cells. We found that CD45 leukocytes are regularly observed in the fallopian tube and are mainly composed of CD163 macrophages, CD11c dendritic cells, and CD8 T cells. In addition, there are minor populations of CD56 NK cells, CD4 T cells, CD20 B cells, TCR?? T cells, and, among dendritic cells, CD207(Langerin) Langerhans cells. The cellular mapping that we performed indicates that the local immune system in the human fallopian tube is composed of a mixture of innate and adaptive immune cells, many of which are recognized as playing a role in cancer immune surveillance. This local immune system could provide a first line of defense against early precancerous lesions and could potentially be exploited for immune-based therapies. PMID:25272297

Ardighieri, Laura; Lonardi, Silvia; Moratto, Daniele; Facchetti, Fabio; Shih, Ie-Ming; Vermi, William; Kurman, Robert J

2014-11-01

195

Peripheral innate immune challenge exaggerated microglia activation, increased the number of inflammatory CNS macrophages, and prolonged social withdrawal in socially defeated mice.  

PubMed

Repeated social defeat (RSD) activates neuroendocrine pathways that have a significant influence on immunity and behavior. Previous studies from our lab indicate that RSD enhances the inflammatory capacity of CD11b? cells in the brain and promotes anxiety-like behavior in an interleukin (IL)-1 and ?-adrenergic receptor-dependent manner. The purpose of this study was to determine the degree to which mice subjected to RSD were more responsive to a secondary immune challenge. Therefore, RSD or control (HCC) mice were injected with saline or lipopolysaccharide (LPS) and activation of brain CD11b? cells and behavioral responses were determined. Peripheral LPS (0.5 mg/kg) injection caused an extended sickness response with exaggerated weight loss and prolonged social withdrawal in socially defeated mice. LPS injection also amplified mRNA expression of IL-1?, tumor necrosis factor (TNF)-?, inducible nitric oxide synthase (iNOS), and CD14 in enriched CD11b? cells isolated from socially defeated mice. In addition, IL-1? mRNA levels in enriched CD11b? cells remained elevated in socially defeated mice 24 h and 72 h after LPS. Moreover, microglia and CNS macrophages isolated from socially defeated mice had the highest CD14 expression after LPS injection. Both social defeat and LPS injection increased the percentage of CD11b?/CD45(high) macrophages in the brain and the number of inflammatory macrophages (CD11b?/CD45(high)/CCR2?) was highest in RSD-LPS mice. Anxiety-like behavior was increased by social defeat, but was not exacerbated by the LPS challenge. Nonetheless, reduced locomotor activity and increased social withdrawal were still present in socially defeated mice 72 h after LPS. Last, LPS-induced microglia activation was most evident in the hippocampus of socially defeated mice. Taken together, these findings demonstrate that repeated social defeat enhanced the neuroinflammatory response and caused prolonged sickness following innate immune challenge. PMID:22386198

Wohleb, Eric S; Fenn, Ashley M; Pacenta, Ann M; Powell, Nicole D; Sheridan, John F; Godbout, Jonathan P

2012-09-01

196

Cervical Cancer Cell Supernatants Induce a Phenotypic Switch from U937-Derived Macrophage-Activated M1 State into M2-Like Suppressor Phenotype with Change in Toll-Like Receptor Profile  

PubMed Central

Cervical cancer (CC) is the second most common cancer among women worldwide. Infection with human papillomavirus (HPV) is the main risk factor for developing CC. Macrophages are important immune effector cells; they can be differentiated into two phenotypes, identified as M1 (classically activated) and M2 (alternatively activated). Macrophage polarization exerts profound effects on the Toll-like receptor (TLR) profile. In this study, we evaluated whether the supernatant of human CC cells HeLa, SiHa, and C-33A induces a shift of M1 macrophage toward M2 macrophage in U937-derived macrophages. Results. The results showed that soluble factors secreted by CC cells induce a change in the immunophenotype of macrophages from macrophage M1 into macrophage M2. U937-derived macrophages M1 released proinflammatory cytokines and nitric oxide; however, when these cells were treated with the supernatant of CC cell lines, we observed a turnover of M1 toward M2. These cells increased CD163 and IL-10 expression. The expression of TLR-3, -7, and -9 is increased when the macrophages were treated with the supernatant of CC cells. Conclusions. Our result strongly suggests that CC cells may, through the secretion of soluble factors, induce a change of immunophenotype M1 into M2 macrophages. PMID:25309919

Sanchez-Reyes, Karina; Bravo-Cuellar, Alejandro; Hernandez-Flores, Georgina; Lerma-Diaz, Jose Manuel; Jave-Suarez, Luis Felipe; Gomez-Lomeli, Paulina; de Celis, Ruth; Aguilar-Lemarroy, Adriana; Dominguez-Rodriguez, Jorge Ramiro; Ortiz-Lazareno, Pablo Cesar

2014-01-01

197

Estrogen promotes Leydig cell engulfment by macrophages in male infertility  

PubMed Central

Male infertility accounts for almost half of infertility cases worldwide. A subset of infertile men exhibit reduced testosterone and enhanced levels of estradiol (E2), though it is unclear how increased E2 promotes deterioration of male fertility. Here, we utilized a transgenic mouse strain that overexpresses human CYP19, which encodes aromatase (AROM+ mice), and mice with knockout of Esr1, encoding estrogen receptor ? (ER?KO mice), to analyze interactions between viable Leydig cells (LCs) and testicular macrophages that may lead to male infertility. In AROM+ males, enhanced E2 promoted LC hyperplasia and macrophage activation via ER? signaling. E2 stimulated LCs to produce growth arrest–specific 6 (GAS6), which mediates phagocytosis of apoptotic cells by bridging cells with surface exposed phosphatidylserine (PS) to macrophage receptors, including the tyrosine kinases TYRO3, AXL, and MER. Overproduction of E2 increased apoptosis-independent extrusion of PS on LCs, which in turn promoted engulfment by E2/ER?-activated macrophages that was mediated by AXL-GAS6-PS interaction. We further confirmed E2-dependant engulfment of LCs by real-time 3D imaging. Furthermore, evaluation of molecular markers in the testes of patients with nonobstructive azoospermia (NOA) revealed enhanced expression of CYP19, GAS6, and AXL, which suggests that the AROM+ mouse model reflects human infertility. Together, these results suggest that GAS6 has a potential as a clinical biomarker and therapeutic target for male infertility. PMID:24762434

Yu, Wanpeng; Zheng, Han; Lin, Wei; Tajima, Astushi; Zhang, Yong; Zhang, Xiaoyan; Zhang, Hongwen; Wu, Jihua; Han, Daishu; Rahman, Nafis A.; Korach, Kenneth S.; Gao, George Fu; Inoue, Ituro; Li, Xiangdong

2014-01-01

198

Bisphosphonates target B cells to enhance humoral immune responses  

PubMed Central

Summary Bisphosphonates are a class of drugs that are widely used to inhibit loss of bone mass in patients. We show here that the administration of clinically relevant doses of bisphosphonates in mice increases antibody responses to live and inactive viruses, proteins, haptens and existing commercial vaccine formulations. Bisphosphonates exert this adjuvant-like activity in the absence of CD4+ and ?? T cells, neutrophils or dendritic cells and their effect does not rely on local macrophage depletion nor does it depend upon Toll-like receptor signaling or the inflammasome. Rather, bisphosphonates target directly B cells and enhance B cell expansion and antibody production upon antigen encounter. These data establish bisphosphonates as a novel class of adjuvants that boost humoral immune responses. PMID:24120862

Tonti, Elena; Jimenez de Oya, Nereida; Galliverti, Gabriele; Moseman, E. Ashley; Di Lucia, Pietro; Amabile, Angelo; Sammicheli, Stefano; De Giovanni, Marco; Sironi, Laura; Chevrier, Nicolas; Sitia, Giovanni; Gennari, Luigi; Guidotti, Luca G.; von Andrian, Ulrich H.; Iannacone, Matteo

2013-01-01

199

Complexity of fatty acid distribution inside human macrophages on single cell level using Raman micro-spectroscopy.  

PubMed

Macrophages are phagocytic cells which are involved in the non-specific immune defense. Lipid uptake and storage behavior of macrophages also play a key role in the development of atherosclerotic lesions within walls of blood vessels. The allocation of exogenous lipids such as fatty acids in the blood stream dictates the accumulation and quantity of lipids within macrophages. In case of an overexposure, macrophages transform into foam cells because of the large amount of lipid droplets in the cytoplasm. Raman micro-spectroscopy is a powerful tool for studying single cells due to the combination of microscopic imaging with spectral information. With a spatial resolution restricted by the diffraction limit, it is possible to visualize lipid droplets within macrophages. With stable isotopic labeling of fatty acids with deuterium, the uptake and storage of exogenously provided fatty acids can be investigated. In this study, we present the results of time-dependent Raman spectroscopic imaging of single THP-1 macrophages incubated with deuterated arachidonic acid. The polyunsaturated fatty acid plays an important role in the cellular signaling pathway as being the precursor of icosanoids. We show that arachidonic acid is stored in lipid droplets but foam cell formation is less pronounced as with other fatty acids. The storage efficiency in lipid droplets is lower than in cells incubated with deuterated palmitic acid. We validate our results with gas chromatography and gain information on the relative content of arachidonic acid and its metabolites in treated macrophages. These analyses also provide evidence that significant amounts of the intracellular arachidonic acid is elongated to adrenic acid but is not metabolized any further. The co-supplementation of deuterated arachidonic acid and deuterated palmitic acid leads to a non-homogenous storage pattern in lipid droplets within single cells. PMID:24939132

Stiebing, Clara; Matthäus, Christian; Krafft, Christoph; Keller, Andrea-Anneliese; Weber, Karina; Lorkowski, Stefan; Popp, Jürgen

2014-11-01

200

Cell-mediated immune phenomena induced by lymphokines from splenic lymphocytes of mice with chronic staphylococcal infection.  

PubMed Central

Splenic lymphocytes from normal mice and from mice displaying delayed hypersensitivity to Staphylococcus aureus were cultured in the presence or absence of specific staphylococcal antigens. The cell-free supernatant fluids from these lymphocyte cultures were assessed for their ability to alter the functional capacities of normal macrophages. It was found that supernatants from staphylococcus-immune cells cultured in vitro with antigen possessed migration inhibitory factor activity and also were capable of stimulating the incorporation of [14C]glucosamine into macrophage membrane glycoproteins. In addition, the lymphokine-containing supernatants were capable of inducing activation of normal macrophages so that they inhibited the multiplication of intracellular Listeria monocytogenes. Although it was not possible to snow any significant enhancement of intracellular killing of S. aureus by the activated macrophages, evidence is presented that suggests that cell-mediated immune responses to S. aureus may significantly enhance pahgocytosis of staphylococci and, thereby, may provide for their rapid clearance from extracellular fluids. PMID:803469

Baughin, R E; Bonventre, P F

1975-01-01

201

Glutamine and the immune system  

Microsoft Academic Search

Summary Glutamine is utilised at a high rate by cells of the immune system in culture and is required to support optimal lymphocyte proliferation and production of cytokines by lymphocytes and macrophages. Macrophage-mediated phagocytosis is influenced by glutamine availability. Hydrolysable glutamine dipeptides can substitute for glutamine to support in vitro lymphocyte and macrophage functions. In man plasma and skeletal muscle

P. C. Calder; P. Yaqoob

1999-01-01

202

Adoptive transfer studies demonstrate that macrophages can induce proteinuria and mesangial cell proliferation  

Microsoft Academic Search

Adoptive transfer studies demonstrate that macrophages can induce proteinuria and mesangial cell proliferation.BackgroundGlomerular macrophage accumulation is a feature of proliferative human and experimental glomerulonephritis. However, our understanding of the role of macrophages in the induction of renal injury is based upon indirect evidence from depletion studies, most of which lack specificity for this cell type. Therefore, an adoptive transfer approach

Yohei Ikezumi; Lynette A Hurst; Takao Masaki; Robert C Atkins; David J Nikolic-Paterson

2003-01-01

203

Macrophage Contact Dependent and Independent TLR4 Mechanisms Induce ?-Cell Dysfunction and Apoptosis in a Mouse Model of Type 2 Diabetes  

PubMed Central

Type 2 diabetes (T2D) is evolving into a global disease and patients have a systemic low-grade inflammation, yet the role of this inflammation is still not established. One plausible mechanism is enhanced expression and activity of the innate immune system. Therefore, we evaluated the expression and the function of the toll-like receptor 4 (TLR4) on pancreatic ?-cells in primary mouse islets and on the murine ?-cell line MIN6 in the presence or absence of macrophages. Diabetic islets have 40% fewer TLR4 positive ?-cells, but twice the number of TLR4 positive macrophages as compared to healthy islets. Healthy and diabetic islets respond to a TLR4 challenge with enhanced production of cytokines (5–10-fold), while the TLR4 negative ?-cell line MIN6 fails to produce cytokines. TLR4 stimulation induces ?-cell dysfunction in mouse islets, measured as reduced glucose stimulated insulin secretion. Diabetic macrophages from 4-months old mice have acquired a transient enhanced capacity to produce cytokines when stimulated with LPS. Interestingly, this is lost in 6-months old diabetic mice. TLR4 activation alone does not induce apoptosis in islets or MIN-6 cells. In contrast, macrophages mediate TLR4-dependent cell-contact dependent (3-fold) as well as cell-contact independent (2-fold) apoptosis of both islets and MIN-6 cells. Importantly, diabetic macrophages have a significantly enhanced capacity to induce ?-cell apoptosis compared to healthy macrophages. Taken together, the TLR4 responsiveness is elevated in the diabetic islets and mainly mediated by newly recruited macrophages. The TLR4 positive macrophages, in both a cell-contact dependent and independent manner, induce apoptosis of ?-cells in a TLR4 dependent fashion and TLR4 activation directly induces ?-cell dysfunction. Thus, targeting either the TLR4 pathway or the macrophages provides a novel attractive treatment regime for T2D. PMID:24594974

Cucak, Helena; Mayer, Christopher; Tonnesen, Morten; Thomsen, Lise H?j; Grunnet, Lars Groth; Rosendahl, Alexander

2014-01-01

204

Immune responses of TLR5 + lamina propria dendritic cells in enterobacterial infection  

Microsoft Academic Search

Toll-like receptors (TLRs) recognize distinct microbial components and induce innate immune responses. TLR5 has been shown\\u000a to recognize bacterial flagellin. Unlike other TLRs, TLR5 is not expressed on conventional dendritic cells or macrophages.\\u000a By contrast, TLR5 is mainly expressed on intestinal CD11c+ lamina propria cells (LPCs), which do not express TLR4. These cells detect pathogenic bacteria and secreted proinflammatory\\u000a cytokines,

Satoshi Uematsu; Shizuo Akira

2009-01-01

205

Riboflavin deprivation inhibits macrophage viability and activity - a study on the RAW 264.7 cell line.  

PubMed

Riboflavin, or vitamin B2, as a precursor of the coenzymes FAD and FMN, has an indirect influence on many metabolic processes and determines the proper functioning of several systems, including the immune system. In the human population, plasma riboflavin concentration varies from 3·1 nM (in a moderate deficiency, e.g. in pregnant women) to 10·4 nM (in healthy adults) and 300 nM (in cases of riboflavin supplementation). The purpose of the present study was to investigate the effects of riboflavin concentration on the activity and viability of macrophages, i.e. on one of the immunocompetent cell populations. The study was performed on the murine monocyte/macrophage RAW 264.7 cell line cultured in medium with various riboflavin concentrations (3·1, 10·4, 300 and 531 nM). The results show that riboflavin deprivation has negative effects on both the activity and viability of macrophages and reduces their ability to generate an immune response. Signs of riboflavin deficiency developed in RAW 264.7 cells within 4 d of culture in the medium with a low riboflavin concentration (3·1 nM). In particular, the low riboflavin content reduced the proliferation rate and enhanced apoptotic cell death connected with the release of lactate dehydrogenase. The riboflavin deprivation impaired cell adhesion, completely inhibited the respiratory burst and slightly impaired phagocytosis of the zymosan particles. In conclusion, macrophages are sensitive to riboflavin deficiency; thus, a low riboflavin intake in the diet may affect the immune system and may consequently decrease proper host immune defence. PMID:23415257

Mazur-Bialy, Agnieszka Irena; Buchala, Beata; Plytycz, Barbara

2013-08-28

206

Crosstalk between colon cancer cells and macrophages via inflammatory mediators and CD47 promotes tumour cell migration.  

PubMed

Tumour-associated macrophages (TAMs) of the M2 phenotype are present in the stroma of many tumours and are frequently associated with the progression of several types of cancer. We investigated the role of M2 macrophages in colon cancer progression and found that human colon cancer tissue had elevated numbers of CD68(+) (macrophage marker) cells and CD206(+) (M2 macrophage marker) cells and increased CD47 expression. To explore potential interplay between colon cancer cells and M2 macrophages, we differentiated the monocyte cell line THP-1 into M1 and M2 macrophages (CD206(high) and Th2 cytokine-secreting cells), respectively. M2 macrophages migrated faster than M1 macrophages towards SW480-conditioned medium. Similarly, M2 macrophage-conditioned medium induced SW480 cell migration and CD47 expression. Factors released by macrophages were involved in this induction. In addition, SW480 cells migrated faster when co-cultured with M2 macrophages. Inhibition of CD47 with blocking antibodies or siRNA significantly reduced the migration of SW480 cells in the presence of M2 macrophages. This effect was further decreased via blocking antibodies against the CD47 ligand signal-regulatory protein ? (SIRP?). Additionally, cancer cells also secreted significant levels of IL-10, thereby promoting M2 macrophage differentiation. These findings indicate that a TAM-enriched tumour microenvironment promotes colon cancer cell migration and metastasis. PMID:23810249

Zhang, Yuan; Sime, Wondossen; Juhas, Maria; Sjölander, Anita

2013-10-01

207

Integrin CD11b positively regulates TLR4-induced signalling pathways in dendritic cells but not in macrophages  

NASA Astrophysics Data System (ADS)

Tuned and distinct responses of macrophages and dendritic cells to Toll-like receptor 4 (TLR4) activation induced by lipopolysaccharide (LPS) underpin the balance between innate and adaptive immunity. However, the molecule(s) that confer these cell-type-specific LPS-induced effects remain poorly understood. Here we report that the integrin ?M (CD11b) positively regulates LPS-induced signalling pathways selectively in myeloid dendritic cells but not in macrophages. In dendritic cells, which express lower levels of CD14 and TLR4 than macrophages, CD11b promotes MyD88-dependent and MyD88-independent signalling pathways. In particular, in dendritic cells CD11b facilitates LPS-induced TLR4 endocytosis and is required for the subsequent signalling in the endosomes. Consistent with this, CD11b deficiency dampens dendritic cell-mediated TLR4-triggered responses in vivo leading to impaired T-cell activation. Thus, by modulating the trafficking and signalling functions of TLR4 in a cell-type-specific manner CD11b fine tunes the balance between adaptive and innate immune responses initiated by LPS.

Ling, Guang Sheng; Bennett, Jason; Woollard, Kevin J.; Szajna, Marta; Fossati-Jimack, Liliane; Taylor, Philip R.; Scott, Diane; Franzoso, Guido; Cook, H. Terence; Botto, Marina

2014-01-01

208

Integrin CD11b positively regulates TLR4-induced signalling pathways in dendritic cells but not in macrophages  

PubMed Central

Tuned and distinct responses of macrophages and dendritic cells to Toll-like receptor 4 (TLR4) activation induced by lipopolysaccharide (LPS) underpin the balance between innate and adaptive immunity. However, the molecule(s) that confer these cell-type-specific LPS-induced effects remain poorly understood. Here we report that the integrin ?M (CD11b) positively regulates LPS-induced signalling pathways selectively in myeloid dendritic cells but not in macrophages. In dendritic cells, which express lower levels of CD14 and TLR4 than macrophages, CD11b promotes MyD88-dependent and MyD88-independent signalling pathways. In particular, in dendritic cells CD11b facilitates LPS-induced TLR4 endocytosis and is required for the subsequent signalling in the endosomes. Consistent with this, CD11b deficiency dampens dendritic cell-mediated TLR4-triggered responses in vivo leading to impaired T-cell activation. Thus, by modulating the trafficking and signalling functions of TLR4 in a cell-type-specific manner CD11b fine tunes the balance between adaptive and innate immune responses initiated by LPS. PMID:24423728

Ling, Guang Sheng; Bennett, Jason; Woollard, Kevin J.; Szajna, Marta; Fossati-Jimack, Liliane; Taylor, Philip R.; Scott, Diane; Franzoso, Guido; Cook, H. Terence; Botto, Marina

2014-01-01

209

Macrophage stimulation by bacterial lipopolysaccharides. I. Cytolytic effect on tumor target cells  

PubMed Central

Bacterial lipopolysaccharides (LPS) stimulate mouse peritoneal macrophages to kill tumor cells in vitro. Lysis is confined to tumor cells where it is nonspecific; both allogeneic and syngeneic cells being susceptible. Stimulation by LPS appears to be due to direct interaction between LPS and macrophages and does not involve participation by lymphocytes. After exposure to LPS, a latent period must elapse before macrophages can lyse tumor cells. The cytolytic mechanism requires contact between target cells and viable effector cells which maintain their lytic capacity for a sustained period and can kill on repeated occasions. The generation of a macrophage cytolytic effect by LPS is critically dependent upon the absolute number of macrophages which must be sufficient to produce confluent monolayers. These findings indicate that LPS stimulation of macrophages in vitro represents a valuable model system for the study of the mechanisms of macrophage stimulation and of the mediation of tumor cell death. PMID:568163

1978-01-01

210

Oral administration of kefiran induces changes in the balance of immune cells in a murine model.  

PubMed

The aim of the present study was to evaluate the effect of the oral administration of kefiran on the balance of immune cells in a murine model. Six week old BALB/c mice were treated with kefiran (300 mg/L) for 0, 2 and 7 days. Kefiran treatment increased the number of IgA+ cells in lamina propria after 2 and 7 days. Percentage of B220+/MHCII(high) cells in mesenteric lymph nodes (2 days) and Peyer's patches (7 days) was higher compared to untreated control mice. An increase of macrophages (F4/80+ cells) was observed in lamina propria and peritoneal cavity (2 and 7 days). In contrast, at day 7, macrophage population decreased in Peyer's patches. These results show the ability of kefiran to modify the balance of immune cells in intestinal mucosa. This property could be highly relevant for the comprehension of the probiotic effect attributed to kefir. PMID:21504180

Medrano, Micaela; Racedo, Silvia M; Rolny, Ivanna S; Abraham, Analía G; Pérez, Pablo F

2011-05-25

211

Orphan Nuclear Receptor Nur77 Is Involved in Caspase-independent Macrophage Cell Death  

Microsoft Academic Search

Activation-induced cell death in macrophages has been observed, but the mechanism remains largely unknown. Activation-induced cell death in macrophages can be independent from caspases, and the death of activated macrophages can even be triggered by the pan-caspase in- hibitor benzyloxycarbonyl-Val-Ala-Asp-fluoromethyl ketone (zVAD). Here, we show that this type of macrophage death can occur in the septic mouse model and that

Sung Ouk Kim; Koh Ono; Peter S. Tobias; Jiahuai Han

2003-01-01

212

CD4+ T Cell-derived IL-10 Promotes Brucella abortus Persistence via Modulation of Macrophage Function  

PubMed Central

Evasion of host immune responses is a prerequisite for chronic bacterial diseases; however, the underlying mechanisms are not fully understood. Here, we show that the persistent intracellular pathogen Brucella abortus prevents immune activation of macrophages by inducing CD4+CD25+ T cells to produce the anti-inflammatory cytokine interleukin-10 (IL-10) early during infection. IL-10 receptor (IL-10R) blockage in macrophages resulted in significantly higher NF-kB activation as well as decreased bacterial intracellular survival associated with an inability of B. abortus to escape the late endosome compartment in vitro. Moreover, either a lack of IL-10 production by T cells or a lack of macrophage responsiveness to this cytokine resulted in an increased ability of mice to control B. abortus infection, while inducing elevated production of pro-inflammatory cytokines, which led to severe pathology in liver and spleen of infected mice. Collectively, our results suggest that early IL-10 production by CD25+CD4+ T cells modulates macrophage function and contributes to an initial balance between pro-inflammatory and anti-inflammatory cytokines that is beneficial to the pathogen, thereby promoting enhanced bacterial survival and persistent infection. PMID:23818855

Xavier, Mariana N.; Winter, Maria G.; Spees, Alanna M.; Nguyen, Kim; Atluri, Vidya L.; Silva, Teane M. A.; Baumler, Andreas J.; Muller, Werner; Santos, Renato L.; Tsolis, Renee M.

2013-01-01

213

An evolving new paradigm: endothelial cells – conditional innate immune cells  

PubMed Central

Endothelial cells (ECs) are a heterogeneous population that fulfills many physiological processes. ECs also actively participate in both innate and adaptive immune responses. ECs are one of the first cell types to detect foreign pathogens and endogenous metabolite-related danger signals in the bloodstream, in which ECs function as danger signal sensors. Treatment with lipopolysaccharide activates ECs, causing the production of pro-inflammatory cytokines and chemokines, which amplify the immune response by recruiting immune cells. Thus, ECs function as immune/inflammation effectors and immune cell mobilizers. ECs also induce cytokine production by immune cells, in which ECs function as immune regulators either by activating or suppressing immune cell function. In addition, under certain conditions, ECs can serve as antigen presenting cells (antigen presenters) by expressing both MHC I and II molecules and presenting endothelial antigens to T cells. These facts along with the new concept of endothelial plasticity suggest that ECs are dynamic cells that respond to extracellular environmental changes and play a meaningful role in immune system function. Based on these novel EC functions, we propose a new paradigm that ECs are conditional innate immune cells. This paradigm provides a novel insight into the functions of ECs in inflammatory/immune pathologies. PMID:23965413

2013-01-01

214

An In Vitro One-Dimensional Assay to Study Growth Factor-Regulated Tumor Cell-Macrophage Interaction  

PubMed Central

Growth factor-dependent pairing and motility between tumor cells and tumor-associated macrophages on extracellular matrix (ECM) fibers of the tumor microenvironment have been shown to enhance intravasation and metastatic spread of breast carcinomas. We describe an in vitro motility assay that combines time- lapse wide-field microscopy and micro-patterned linear adhesive substrates to reconstitute the in vivo behavior between macrophages, tumor cells, and ECM fibers in orthotopic rodent tumor models observed by intravital imaging. Commercially available linear stripes of 650 nm dye-labeled fibronectin microlithographed onto glass cover slips are sequentially plated with fluorescently labeled MTLn3 tumor cells and bone marrow-derived macrophages and time-lapse imaged for up to 8 h. Incubation with pharmacological inhibitors during the assay can identify important paracrine or autocrine signaling pathways involved in the macrophage–tumor cell interaction. This high-resolution motility assay will lead to a more detailed description of immune cell–tumor cell behavior as well as interrogating additional cell types within the tumor microenvironment which use cytokine/growth factor paracrine signaling interactions to facilitate intravasation and metastasis. PMID:24908299

Sharma, Ved P.; Beaty, Brian T.; Cox, Dianne; Condeelis, John S.; Eddy, Robert J.

2014-01-01

215

Uranyl nitrate-exposed rat alveolar macrophages cell death: Influence of superoxide anion and TNF ? mediators  

SciTech Connect

Uranium compounds are widely used in the nuclear fuel cycle, military and many other diverse industrial processes. Health risks associated with uranium exposure include nephrotoxicity, cancer, respiratory, and immune disorders. Macrophages present in body tissues are the main cell type involved in the internalization of uranium particles. To better understand the pathological effects associated with depleted uranium (DU) inhalation, we examined the metabolic activity, phagocytosis, genotoxicity and inflammation on DU-exposed rat alveolar macrophages (12.5–200 ?M). Stability and dissolution of DU could differ depending on the dissolvent and in turn alter its biological action. We dissolved DU in sodium bicarbonate (NaHCO{sub 3} 100 mM) and in what we consider a more physiological vehicle resembling human internal media: sodium chloride (NaCl 0.9%). We demonstrate that uranyl nitrate in NaCl solubilizes, enters the cell, and elicits its cytotoxic effect similarly to when it is diluted in NaHCO{sub 3}. We show that irrespective of the dissolvent employed, uranyl nitrate impairs cell metabolism, and at low doses induces both phagocytosis and generation of superoxide anion (O{sub 2}{sup ?}). At high doses it provokes the secretion of TNF? and through all the range of doses tested, apoptosis. We herein suggest that at DU low doses O{sub 2}{sup ?} may act as the principal mediator of DNA damage while at higher doses the signaling pathway mediated by O{sub 2}{sup ?} may be blocked, prevailing damage to DNA by the TNF? route. The study of macrophage functions after uranyl nitrate treatment could provide insights into the pathophysiology of uranium?related diseases. -- Highlights: ? Uranyl nitrate effect on cultured macrophages is linked to the doses and independent of its solubility. ? At low doses uranyl nitrate induces generation of superoxide anion. ? At high doses uranyl nitrate provokes secretion of TNF?. ? Uranyl nitrate induces apoptosis through all the range of doses tested.

Orona, N.S. [School of Science and Technology, National University of General Martín, Avda Gral Paz 5445 (1650) San Martín, Buenos Aires (Argentina)] [School of Science and Technology, National University of General Martín, Avda Gral Paz 5445 (1650) San Martín, Buenos Aires (Argentina); Tasat, D.R., E-mail: deborah.tasat@unsam.edu.ar [School of Science and Technology, National University of General Martín, Avda Gral Paz 5445 (1650) San Martín, Buenos Aires (Argentina); School of Dentistry, University of Buenos Aires, M. T. de Alvear 2142 (1122), Buenos Aires (Argentina)

2012-06-15

216

Induction of interleukin-12 production in mouse macrophages by berberine, a benzodioxoloquinolizine alkaloid, deviates CD4+ T cells from a Th2 to a Th1 response  

PubMed Central

In this study we investigated whether berberine-mediated induction of interleukin-12 (IL-12) production in antigen-presenting cells could regulate a cytokine profile of antigen-primed CD4+ T helper (Th) cells. Pretreatment with berberine induced IL-12 production in both macrophages and dendritic cells, and significantly increased the levels of IL-12 production in lipopolysaccharide-stimulated macrophages and in CD40 ligand-stimulated dendritic cells. Importantly, berberine pretreatment of macrophages increased their ability to induce interferon-? (IFN-?) and reduced their ability to induce IL-4 in antigen-primed CD4+ T cells. Berberine did not influence the macrophage cell surface expression of the class II major histocompatibility complex molecule, the co-stimulatory molecules CD80 and CD86, and intracellular adhesion molecule-1. Addition of neutralizing anti-IL-12p40 monoclonal antibody to cultures of berberine-pretreated macrophages and CD4+ T cells restored IL-4 production in antigen-primed CD4+ T cells. The in vivo administration of berberine resulted in the enhanced induction of IL-12 production by macrophages when stimulated in vitro with lipopolysaccharide or heat-killed Listeria monocytogenes, leading to the inhibition of the Th type 2 cytokine profile (decreased IL-4 and increased IFN-? production) in antigen-primed CD4+ T cells. These findings may point to a possible therapeutic use of berberine or medicinal plants containing berberine in the Th type 2 cell-mediated immune diseases such as allergic diseases. PMID:12807487

Kim, Tae S; Kang, Bok Y; Cho, Daeho; Kim, Seung H

2003-01-01

217

Mucosal dendritic cells shape mucosal immunity  

PubMed Central

Dendritic cells (DCs) are key modulators that shape the immune system. In mucosal tissues, DCs act as surveillance systems to sense infection and also function as professional antigen-presenting cells that stimulate the differentiation of naive T and B cells. On the basis of their molecular expression, DCs can be divided into several subsets with unique functions. In this review, we focus on intestinal DC subsets and their function in bridging the innate signaling and adaptive immune systems to maintain the homeostasis of the intestinal immune environment. We also review the current strategies for manipulating mucosal DCs for the development of efficient mucosal vaccines to protect against infectious diseases. PMID:24626170

Chang, Sun-Young; Ko, Hyun-Jeong; Kweon, Mi-Na

2014-01-01

218

Efficient natural defense mechanisms against Listeria monocytogenes in T and B cell-deficient allogeneic bone marrow radiation chimeras. Preactivated macrophages are the main effector cells in an early phase after bone marrow transfer  

Microsoft Academic Search

Radiation chimeras in the early phase after bone marrow transplantation are a good model to study the efficiency of the body's nonspecific defense system represented by macrophages (M phi), polymorphonuclear cells (PMN), and NK cells. These cell types are present in large numbers in spleen and liver at that time, whereas the specific immune system represented by T and B

J. Roesler; E. B. Groettrup; M. Baccarini; M. L. Lohmann-Mattes

1989-01-01

219

Macrophage Autophagy in Atherosclerosis  

PubMed Central

Macrophages play crucial roles in atherosclerotic immune responses. Recent investigation into macrophage autophagy (AP) in atherosclerosis has demonstrated a novel pathway through which these cells contribute to vascular inflammation. AP is a cellular catabolic process involving the delivery of cytoplasmic contents to the lysosomal machinery for ultimate degradation and recycling. Basal levels of macrophage AP play an essential role in atheroprotection during early atherosclerosis. However, AP becomes dysfunctional in the more advanced stages of the pathology and its deficiency promotes vascular inflammation, oxidative stress, and plaque necrosis. In this paper, we will discuss the role of macrophages and AP in atherosclerosis and the emerging evidence demonstrating the contribution of macrophage AP to vascular pathology. Finally, we will discuss how AP could be targeted for therapeutic utility. PMID:23401644

Maiuri, Maria Chiara; Grassia, Gianluca; Platt, Andrew M.; Carnuccio, Rosa; Ialenti, Armando; Maffia, Pasquale

2013-01-01

220

Some immune cells appear to aid cancer cell growth  

Cancer.gov

The immune system is normally known for protecting the body from illness. But a subset of immune cells appear to be doing more harm than good. A new study from researchers at the University of Michigan Comprehensive Cancer Center found that these cells, called myeloid derived suppressor cells, provide a niche where the cancer stem cells survive.

221

TLR2 and TLR4 signaling pathways are required for recombinant Brucella abortus BCSP31-induced cytokine production, functional upregulation of mouse macrophages, and the Th1 immune response in vivo and in vitro  

PubMed Central

Brucella abortus is a zoonotic Gram-negative pathogen that causes brucelosis in ruminants and humans. Toll-like receptors (TLRs) recognize Brucella abortus and initiate antigen-presenting cell activities that affect both innate and adaptive immunity. In this study, we focused on recombinant Brucella cell-surface protein 31 (rBCSP31) to determine its effects on mouse macrophages. Our results demonstrated that rBCSP31 induced TNF-?, IL-6 and IL-12p40 production, which depended on the activation of mitogen-activated protein kinases (MAPKs) by stimulating the rapid phosphorylation of p38 and JNK and the activation of transcription factor NF-?B in macrophages. In addition, continuous exposure (>24 h) of RAW264.7 cells to rBCSP31 significantly enhanced IFN-?-induced expression of MHC-II and the ability to present rBCSP31 peptide to CD4+ T cells. Furthermore, we found that rBCSP31 could interact with both TLR2 and TLR4. The rBCSP31-induced cytokine production by macrophages from TLR2?/? and TLR4?/? mice was lower than that from C57BL/6 macrophages, and the activation of NF-?B and MAPKs was attenuated in macrophages from TLR2?/? and TLR4?/? mice. In addition, CD4+ T cells from C57BL/6 mice immunized with rBCSP31 produced higher levels of IFN-? and IL-2 compared with CD4+ T cells from TLR2?/? and TLR4?/? mice. Macrophages from immunized C57BL/6 mice produced higher levels of IL-12p40 than those from TLR2?/? and TLR4?/? mice. Furthermore, immunization with rBCSP31 provided better protection in C57BL/6 mice than in TLR2?/? and TLR4?/? mice after B. abortus 2308 challenge. These results indicate that rBCSP31 is a TLR2 and TLR4 agonist that induces cytokine production, upregulates macrophage function and induces the Th1 immune response. PMID:24769793

Li, Jia-Yun; Liu, Yuan; Gao, Xiao-Xue; Gao, Xiang; Cai, Hong

2014-01-01

222

[Cannabinoids and the immune system. Of men, mice and cells].  

PubMed

The medical use of cannabis or cannabinoid compounds is controversial. Cannabinoids like the Delta(9)-THC (tetrahydrocannabinol) or the synthetic derivative Nabilone are available against cancer- and HIV-associated cachexia, nausea and vomiting. Over the last 20 years, the cannabinoid receptors CB(1) and CB(2) and their endogenous ligands have been found. The involvement of this endogenous cannabinoid signalling system in feeding, appetite, pain perception and immunomodulation could be demonstrated using animal and in vitro studies. Thus, the concern about immunosuppressive effects in humans using medical cannabinoid preparations grew. However, up to now most human studies have failed to demonstrate a well-defined and reproducible immunosuppressive cannabinoid-effect. Only the smoking of marijuana showed a significant local immunosuppression of the bactericidal activity of human alveolar macrophages. In animal studies, cannabinoids were identified as potent modulators of cytokine production, causing a shift from Th1 to Th2 cytokines. In consequence, a compromised cellular immunity was observed in these animals, resulting in enhanced tumor growth and reduced immunity to viral infections. In vitro, immunosuppressive effects were shown in all immune cells, but only at high micromolar cannabinoid concentrations not reached under normal clinical conditions. In conclusion, there is no evidence that cannabinoids induce a serious, relevant immunosuppression in humans, with the exception of marijuana-smoking which may affect local broncho-alveolar immunity. PMID:15221424

Kraft, B; Kress, H G

2004-06-01

223

Macrophage migration inhibitory factor (MIF) is a critical mediator of the innate immune response to Mycobacterium tuberculosis  

PubMed Central

Macrophage migration inhibitory factor (MIF), an innate cytokine encoded in a functionally polymorphic genetic locus, contributes to detrimental inflammation but may be crucial for controlling infection. We explored the role of variant MIF alleles in tuberculosis. In a Ugandan cohort, genetic low expressers of MIF were 2.4-times more frequently identified among patients with Mycobacterium tuberculosis (TB) bacteremia than those without. We also found mycobacteria-stimulated transcription of MIF and serum MIF levels to be correlated with MIF genotype in human macrophages and in a separate cohort of US TB patients, respectively. To determine mechanisms for MIF’s protective role, we studied both aerosolized and i.v. models of mycobacterial infection and observed MIF-deficient mice to succumb more quickly with higher organism burden, increased lung pathology, and decreased innate cytokine production (TNF-?, IL-12, IL-10). MIF-deficient animals showed increased pulmonary neutrophil accumulation but preserved adaptive immune response. MIF-deficient macrophages demonstrated decreased cytokine and reactive oxygen production and impaired mycobacterial killing. Transcriptional investigation of MIF-deficient macrophages revealed reduced expression of the pattern recognition receptor dectin-1; restoration of dectin-1 expression recovered innate cytokine production and mycobacterial killing. Our data place MIF in a crucial upstream position in the innate immune response to mycobacteria and suggest that commonly occurring low expression MIF alleles confer an increased risk of TB disease in some populations. PMID:23882081

Das, Rituparna; Koo, Mi-Sun; Kim, Bae Hoon; Jacob, Shevin T.; Subbian, Selvakumar; Yao, Jie; Leng, Lin; Levy, Rebecca; Murchison, Charles; Burman, William J.; Moore, Christopher C.; Scheld, W. Michael; David, John R.; Kaplan, Gilla; MacMicking, John D.; Bucala, Richard

2013-01-01

224

Differential rates of replacement of human dermal dendritic cells and macrophages during hematopoietic stem cell transplantation  

PubMed Central

Animal models of hematopoietic stem cell transplantation have been used to analyze the turnover of bone marrow–derived cells and to demonstrate the critical role of recipient antigen-presenting cells (APC) in graft versus host disease (GVHD). In humans, the phenotype and lineage relationships of myeloid-derived tissue APC remain incompletely understood. It has also been proposed that the risk of acute GVHD, which extends over many months, is related to the protracted survival of certain recipient APC. Human dermis contains three principal subsets of CD45+HLA-DR+ cells: CD1a+CD14? DC, CD1a?CD14+ DC, and CD1a?CD14+FXIIIa+ macrophages. In vitro, each subset has characteristic properties. After transplantation, both CD1a+ and CD14+ DC are rapidly depleted and replaced by donor cells, but recipient macrophages can be found in GVHD lesions and may persist for many months. Macrophages isolated from normal dermis secrete proinflammatory cytokines. Although they stimulate little proliferation of naive or memory CD4+ T cells, macrophages induce cytokine expression in memory CD4+ T cells and activation and proliferation of CD8+ T cells. These observations suggest that dermal macrophages and DC are from distinct lineages and that persistent recipient macrophages, although unlikely to initiate alloreactivity, may contribute to GVHD by sustaining the responses of previously activated T cells. PMID:19171766

Haniffa, Muzlifah; Ginhoux, Florent; Wang, Xiao-Nong; Bigley, Venetia; Abel, Michal; Dimmick, Ian; Bullock, Sarah; Grisotto, Marcos; Booth, Trevor; Taub, Peter; Hilkens, Catharien; Merad, Miriam

2009-01-01

225

Critical Role of Macrophages and Their Activation via MyD88-NFkappaB Signaling in Lung Innate Immunity to Mycoplasma pneumoniae  

Microsoft Academic Search

Mycoplasma pneumoniae (Mp), a common cause of pneumonia, is associated with asthma; however, the mechanisms underlying this association remain unclear. We investigated the cellular immune response to Mp in mice. Intranasal inoculation with Mp elicited infiltration of the lungs with neutrophils, monocytes and macrophages. Systemic depletion of macrophages, but not neutrophils, resulted in impaired clearance of Mp from the lungs.

Jen-Feng Lai; Carlene L. Zindl; Lynn B. Duffy; T. Prescott Atkinson; Yong Woo Jung; Nico van Rooijen; Ken B. Waites; Duncan C. Krause; David D. Chaplin; Jörn Coers

2010-01-01

226

High-mobility group box protein-1 released by human-periodontal ligament cells modulates macrophage migration and activity in vitro.  

PubMed

Recent studies have demonstrated the interplay of human periodontal ligament cells (hPDLs) with immune cells, such as macrophages, during tissue repair. High-mobility group box protein-1 (HMGB1) is released into the extracellular milieu by damaged cells and functions as an alarmin to mediate the inflammatory host response. The present study addressed the role of HMGB1 released by hPDLs in the regulation of macrophage differentiation, migration and activity. The aim was to examine the inflammatory potential of HMGB1 itself and in combination with other mediators. The induction of sterile necrosis by thermal insult of hPDLs resulted in HMGB1 translocation from the nucleus to the cytoplasm and on to the extracellular space, as determined by immunocytochemistry/ELISA. Exposure of human macrophages to the conditioned PDL cell medium increased the expression of macrophage differentiation/activation markers CD14, CD23, CD64 and CD163. Chemotactic migration and osteoclastic differentiation of macrophages were also enhanced. Supplementation of the conditioned medium with a saturating concentration of HMGB1-Ab reduced these effects. Challenge with recombinant HMGB1 protein induced less migration and osteoclast differentiation than thermal insult. These data point to the immune modulatory capacity of hPDLs by the release of mediators, including HMGB1, which modify macrophage differentiation, migration and activity during periodontal repair, and indicate an enhanced HMGB1 activity when acting in concert with other mediators. PMID:24107514

Wolf, Michael; Lossdörfer, Stefan; Craveiro, Rogerio; Jäger, Andreas

2014-10-01

227

Antibody to the Type 3 Capsule Facilitates Immune Adherence of Pneumococci to Erythrocytes and Augments Their Transfer to Macrophages  

Microsoft Academic Search

Streptococcus pneumoniae has been shown to bind to erythrocytes via a process called immune adherence. This adherence and the subsequent transfer of pneumococci from erythrocytes to macrophages are both dependent on complement C3 deposition onto the pneumococcal surface. The observation that anti-capsule antibody increases C3 deposition on the pneumococcal capsule indicated that anti-capsule antibody may also facilitate the clearance of

Jie Li; Alexander J. Szalai; Susan K. Hollingshead; Moon H. Nahm; David E. Briles

2009-01-01

228

Resiquimod, a TLR7/8 agonist, promotes differentiation of myeloid-derived suppressor cells into macrophages and dendritic cells.  

PubMed

Myeloid-derived suppressor cells (MDSCs) accumulate in cancer patients and tumor-bearing mice, subsequently suppressing the host immune system. MDSCs represent a group of immature myeloid cells expressing CD11b and Gr-1. Here, we show that a Toll-like receptor (TLR) agonist, resiquimod, which binds to TLR7 and TLR8, induces the differentiation of MDSCs into mature myeloid cells. MDSCs were isolated from mice bearing mammary carcinoma 4T1 cells, and the purified MDSCs were cultured in the presence of resiquimod for 5 days. Phenotypic analysis showed that the resiquimod-treated MDSCs differentiated into F4/80(+) macrophages and CD11c(+)/I-A(d+) dendritic cells. Functional analysis showed that the MDSCs also lost their suppressive activity on T cells. Resiquimod-treated MDSCs significantly enhanced the proliferation of T cells that were treated with anti-CD3 and anti-CD28 monoclonal antibodies. These results show that resiquimod induces the differentiation of MDSCs into macrophages and dendritic cells, and also suggest that resiquimod may improve cancer immunotherapy by reducing immunosuppressive MDSCs. PMID:24748512

Lee, Moonkyu; Park, Chan-Su; Lee, Young-Ran; Im, Sun-A; Song, Sukgil; Lee, Chong-Kil

2014-09-01

229

Distinct Dendritic Cell Subsets Differentially Regulate the Class of Immune Response in vivo  

Microsoft Academic Search

Dendritic cells (DCs) are unique in their ability to stimulate T cells and initiate adaptive immunity. Injection of mice with the cytokine Flt3-ligand (FL) dramatically expands mature lymphoid and myeloid-related DC subsets. In contrast, injection of a polyethylene glycol-modified form of granulocyte\\/macrophage colony-stimulating factor (GM-CSF) into mice only expands the myeloid-related DC subset. These DC subsets differ in the cytokine

B. Pulendran; J. L. Smith; G. Caspary; K. Brasel; D. Pettit; E. Maraskovsky; C. R. Maliszewski

1999-01-01

230

Cell-mediated immunity against connective tissue in experimental pulmonary fibrosis  

Microsoft Academic Search

Cell-mediated immunity against an extract of homologous normal lung connective tissue was determined in vitro in spleen cells\\u000a from CD1 mice with bleomycin-induced pulmonary fibrosis. Blastoid transformation and macrophage migration inhibitory factor\\u000a (MIF) were measured at intervals in spleen lymphocytes for a total of seven weeks after the initiation of the fibrogenic process.\\u000a MIF production was evident from the third

R. E. Carvajal; R. González; M. Selman

1982-01-01

231

Profiling B cell immune responses by microengraving  

E-print Network

The ability to monitor an immune response in the course of vaccination or disease progression is highly desirable. Currently, no technique is able to generate a comprehensive profile of the individual cells involved and ...

Papa, Eliseo

2008-01-01

232

Donor Immune Cells Attack Metastatic Breast Cancer  

Cancer.gov

In patients with metastatic breast cancer, immune cells from a genetically matched donor can attack and shrink tumors, researchers from the National Cancer Institute (NCI) announced today at the Annual Meeting of the American Society of Clinical Oncology in Chicago.

233

From mouth to macrophage: mechanisms of innate immune subversion by Mycobacterium avium subsp. paratuberculosis  

PubMed Central

Johne’s disease (JD) is a chronic enteric infection of cattle caused by Mycobacterium avium subsp. paratuberculosis (MAP). The high economic cost and potential zoonotic threat of JD have driven efforts to develop tools and approaches to effectively manage this disease within livestock herds. Efforts to control JD through traditional animal management practices are complicated by MAP’s ability to cause long-term environmental contamination as well as difficulties associated with diagnosis of JD in the pre-clinical stages. As such, there is particular emphasis on the development of an effective vaccine. This is a daunting challenge, in large part due to MAP’s ability to subvert protective host immune responses. Accordingly, there is a priority to understand MAP’s interaction with the bovine host: this may inform rational targets and approaches for therapeutic intervention. Here we review the early host defenses encountered by MAP and the strategies employed by the pathogen to avert or subvert these responses, during the critical period between ingestion and the establishment of persistent infection in macrophages. PMID:24885748

2014-01-01

234

From mouth to macrophage: mechanisms of innate immune subversion by Mycobacterium avium subsp. paratuberculosis.  

PubMed

Johne's disease (JD) is a chronic enteric infection of cattle caused by Mycobacterium avium subsp. paratuberculosis (MAP). The high economic cost and potential zoonotic threat of JD have driven efforts to develop tools and approaches to effectively manage this disease within livestock herds. Efforts to control JD through traditional animal management practices are complicated by MAP's ability to cause long-term environmental contamination as well as difficulties associated with diagnosis of JD in the pre-clinical stages. As such, there is particular emphasis on the development of an effective vaccine. This is a daunting challenge, in large part due to MAP's ability to subvert protective host immune responses. Accordingly, there is a priority to understand MAP's interaction with the bovine host: this may inform rational targets and approaches for therapeutic intervention. Here we review the early host defenses encountered by MAP and the strategies employed by the pathogen to avert or subvert these responses, during the critical period between ingestion and the establishment of persistent infection in macrophages. PMID:24885748

Arsenault, Ryan J; Maattanen, Pekka; Daigle, Joanna; Potter, Andrew; Griebel, Philip; Napper, Scott

2014-01-01

235

Cell-mediated immunity in rheumatoid arthritis  

Microsoft Academic Search

Cell-mediated immunity in rheumatoid arthritis (RA) was assessed by skin testing with six antigens in 107 patients, 94 of whom were age, sex, and race-matched with healthy individuals or patients with diseases unrelated to immunological abnormalities. 20% of RA patients were anergic. Impaired cell-mediated immunity in the RA patients was manifested by a decrease in the magnitude of skin reactivity

A A Andrianakos; J T Sharp; D A Person; M D Lidsky; J Duffy

1977-01-01

236

Role of complement component C1q in phagocytosis of Listeria monocytogenes by murine macrophage-like cell lines.  

PubMed Central

Listeria monocytogenes is a facultative intracellular pathogen of a great variety of cells. Among them, macrophages constitute the major effector cells of listerial immunity during the course of an infection. Although the molecular bases of L. monocytogenes attachment and entry to phagocytes are not completely understood, it has been demonstrated that C3b significantly increases L. monocytogenes uptake by macrophages via complement receptor type 3. The first component of complement, C1q, is present in organic fluids at a relatively high concentration, and C1q receptor sites in macrophages are also abundant. In the present report, results of studies on the role of C1q in the internalization and infectivity of L. monocytogenes by macrophages are presented. L. monocytogenes uptake is enhanced by prior treatment of bacteria with normal sera. Heated serum or C1q-deficient serum abrogates this enhancement. Purified C1q specifically restored uptake. This effect was blocked by the addition of F(ab')2 anti-C1q antibody but not by an irrelevant matched antibody. Direct binding of C1q to L. monocytogenes was specific, saturable, and dose dependent with both fluorescent and radiolabeled C1q. N-Acetyl-D-alanyl-L-isoglutamine, diaminopimelic acid, and L-rhamnose caused a significant dose-dependent inhibition of C1q binding to bacteria, suggesting that these molecules, at least, are involved in the attachment of C1q to L. monocytogenes cell wall. When C1q binding structures on macrophage-like cells were blocked with saturating concentrations of C1q, the uptake of C1q-opsonized bacteria was less than in untreated cells. These experiments demonstrate that, in addition to other reported mechanisms, L. monocytogenes binds C1q, which mediates enhanced uptake by macrophages through C1q binding structures. Images PMID:8359889

Alvarez-Dominguez, C; Carrasco-Marin, E; Leyva-Cobian, F

1993-01-01

237

Conditioned medium from alternatively activated macrophages induce mesangial cell apoptosis via the effect of Fas  

SciTech Connect

During inflammation in the glomerulus, the proliferation of myofiroblast-like mesangial cells is commonly associated with the pathological process. Macrophages play an important role in regulating the growth of resident mesangial cells in the glomeruli. Alternatively activated macrophage (M2 macrophage) is a subset of macrophages induced by IL-13/IL-4, which is shown to play a repair role in glomerulonephritis. Prompted by studies of development, we performed bone marrow derived macrophage and rat mesangial cell co-culture study. Conditioned medium from IL-4 primed M2 macrophages induced rat mesangial cell apoptosis. The pro-apoptotic effect of M2 macrophages was demonstrated by condensed nuclei stained with Hoechst 33258, increased apoptosis rates by flow cytometry analysis and enhanced caspase-3 activation by western blot. Fas protein was up-regulated in rat mesangial cells, and its neutralizing antibody ZB4 partly inhibited M2 macrophage-induced apoptosis. The up-regulated arginase-1 expression in M2 macrophage also contributed to this apoptotic effect. These results indicated that the process of apoptosis triggered by conditioned medium from M2 macrophages, at least is partly conducted through Fas in rat mesangial cells. Our findings provide compelling evidence that M2 macrophages control the growth of mesangial cells in renal inflammatory conditions. - Highlights: • Conditioned-medium from M2 macrophages induces rat mesangial cell (MsC) apoptosis. • M2 macrophage conditioned medium exerts its pro-apoptotic effects via Fas ligand. • Arginase-1 activity in M2 macrophages plays a role in inducing apoptosis in rat MsC.

Huang, Yuan; Luo, Fangjun; Li, Hui; Jiang, Tao; Zhang, Nong, E-mail: nzhang@fudan.edu.cn

2013-11-15

238

Innate immune activation in the pathogenesis of a murine model of globoid cell leukodystrophy.  

PubMed

Globoid cell leukodystrophy is a lysosomal storage disease characterized by the loss of galactocerebrosidase. Galactocerebrosidase loss leads to the accumulation of psychosine and subsequent oligodendrocyte cell death, demyelination, macrophage recruitment, and astroglial activation and proliferation. To date, no studies have elucidated the mechanism of glial cell activation and cytokine and chemokine up-regulation and release. We explored a novel explanation for the development of the pathological changes in the early stages of globoid cell leukodystrophy associated with toll-like receptor (TLR) 2 up-regulation in the hindbrain and cerebellum as a response to dying oligodendrocytes. TLR2 up-regulation on microglia/macrophages coincided with morphological changes consistent with activation at 2 and 3 weeks of age. TLR2 up-regulation on activated microglia/macrophages resulted in astrocyte activation and marked up-regulation of cytokines/chemokines. Because oligodendrocyte cell death is an important feature of globoid cell leukodystrophy, we tested the ability of TLR2 reporter cells to respond to oligodendrocyte cell death. These reporter cells responded in vitro to medium conditioned by psychosine-treated oligodendrocytes, indicating the likelihood that oligodendrocytes release a TLR2 ligand during apoptosis. TLRs are a member of the innate immune system and initiate immune and inflammatory events; therefore, the identification of TLR2 as a potential driver in the activation of central nervous system glial activity in globoid cell leukodystrophy may provide important insight into its pathogenesis. PMID:24316110

Snook, Eric R; Fisher-Perkins, Jeanne M; Sansing, Hope A; Lee, Kim M; Alvarez, Xavier; MacLean, Andrew G; Peterson, Karin E; Lackner, Andrew A; Bunnell, Bruce A

2014-02-01

239

Engulfment of apoptotic cells by macrophages: a role of microRNA-21 in the resolution of wound inflammation.  

PubMed

At an injury site, efficient clearance of apoptotic cells by wound macrophages or efferocytosis is a prerequisite for the timely resolution of inflammation. Emerging evidence indicates that microRNA-21 (miR-21) may regulate the inflammatory response. In this work, we sought to elucidate the significance of miR-21 in the regulation of efferocytosis-mediated suppression of innate immune response, a key process implicated in resolving inflammation following injury. An increased expression of inducible miR-21 was noted in postefferocytotic peripheral blood monocyte-derived macrophages. Such induction of miR-21 was associated with silencing of its target genes PTEN and PDCD4. Successful efferocytosis of apoptotic cells by monocyte-derived macrophages resulted in the suppression of LPS-induced NF-?B activation and TNF-? expression. Interestingly, bolstering of miR-21 levels alone, using miR mimic, resulted in significant suppression of LPS-induced TNF-? expression and NF-?B activation. We report that efferocytosis-induced miR-21, by silencing PTEN and GSK3?, tempers the LPS-induced inflammatory response. Macrophage efferocytosis is known to trigger the release of anti-inflammatory cytokine IL-10. This study demonstrates that following successful efferocytosis, miR-21 induction in macrophages silences PDCD4, favoring c-Jun-AP-1 activity, which in turn results in elevated production of anti-inflammatory IL-10. In summary, this work provides direct evidence implicating miRNA in the process of turning on an anti-inflammatory phenotype in the postefferocytotic macrophage. Elevated macrophage miR-21 promotes efferocytosis and silences target genes PTEN and PDCD4, which in turn accounts for a net anti-inflammatory phenotype. Findings of this study highlight the significance of miRs in the resolution of wound inflammation. PMID:24391209

Das, Amitava; Ganesh, Kasturi; Khanna, Savita; Sen, Chandan K; Roy, Sashwati

2014-02-01

240

Transfer of extracellular vesicles during immune cell-cell interactions  

PubMed Central

SUMMARY The transfer of molecules between cells during cognate immune cell interactions has been reported, and recently a novel mechanism of transfer of proteins and genetic material such as small RNA between T cells and APCs has been described, involving exchange of extracellular vesicles (EVs) during the formation of the immunological synapse (IS). EVs – a term that encompasses exosomes and microvesicles – have been implicated in cell-cell communication during immune responses associated with tumors, pathogens, allergies and autoimmune diseases. This review focuses on EV transfer as a mechanism for the exchange of molecules during immune cell-cell interactions. PMID:23278745

Gutierrez-Vazquez, Cristina; Villarroya-Beltri, Carolina; Mittelbrunn, Maria; Sanchez-Madrid, Francisco

2013-01-01

241

Cell-mediated Transfer of Catalase Nanoparticles from Macrophages to Brain Endothelial and Neural Cells  

PubMed Central

Background Our laboratories forged the concept of macrophage delivery of protein antioxidants to attenuate neuroinflammation and nigrostriatal degeneration in Parkinson’s disease (PD). Notably, the delivery of the redox enzyme, catalase, incorporated into a polyion complex micelle (“nanozyme”) by bone marrow-derived macrophages protected the nigrostriatal against 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) intoxication. Nonetheless, how macrophage delivery of nanozyme increases the efficacy of catalase remains unknown. Methods Herein, we examined the transfer of nanozyme from macrophages to brain microvessel endothelial cells, neurons and astrocytes. Results Facilitated transport of the nanozyme from macrophages to endothelial and neural target cells occurred through endocytosis-independent mechanisms that involved fusion of cellular membranes; macrophage bridging conduits; and nanozyme lipid coatings. Nanozyme transfer was operative across an artificial blood brain barrier and showed efficient reactive oxygen species decomposition. Conclusion This is the first demonstration that drug-loaded macrophages discharge particles to contiguous target cells for potential therapeutic brain enzyme delivery. The pathways for drug delivery shown may be used for the treatment of degenerative disorders of the nervous system. PMID:21449849

Haney, Matthew J.; Zhao, Yuling; Li, Shu; Higginbotham, Sheila M.; Booth, Stephanie L.; Han, Huai-Yun; Vetro, Joseph A.; Mosley, R. Lee; Kabanov, Alexander V.; Gendelman, Howard E.; Batrakova, Elena V.

2011-01-01

242

T Cell Immune Reconstitution Following Lymphodepletion  

PubMed Central

T cell reconstitution following lymphopenia from chemotherapy or stem cell transplant is often slow and incompetent, contributing to the development of infectious diseases, relapse, and graft-versus-host disease. This is due to the fact that de novo T cell production is impaired following cytoreductive regimens. T cells can be generated from two pathways: 1) thymus derived through active thymopoiesis and 2) peripherally expanded clones through homeostatic proliferation. In the development of lymphopenia, the thymic pathway is commonly compromised in adults and T cells rely upon peripheral expansion to recover T cell numbers. This homeostatic proliferation exploits the high cytokine levels following lymphopenia to rapidly generate T cells in the periphery. Moreover, this early peripheral expansion of T cells can also be driven by exogenous antigen. This results in loss of T cell repertoire diversity and may predispose to auto- or alloimmunity. Alternatively, the high homeostatic proliferation following lymphopenia may facilitate expansion of anti-tumor immunity. Murine and human studies have provided insight into the cytokine and cellular regulators of these two pathways of T cell generation and the disparate portraits of T cell immunity created through robust thymopoiesis or peripheral expansion following lymphopenia. This insight has permitted the manipulation of the immune system to maximize anti-tumor immunity through lymphopenia and led to an appreciation of mechanisms that underlie graft vs. host disease. PMID:18023361

Williams, Kirsten; Hakim, Frances T.; Gress, Ronald E.

2007-01-01

243

Microvesicles secreted by macrophages shuttle invasion-potentiating microRNAs into breast cancer cells  

PubMed Central

Background Tumor-associated macrophages (TAMs) are alternatively activated cells induced by interleukin-4 (IL-4)-releasing CD4+ T cells. TAMs promote breast cancer invasion and metastasis; however, the mechanisms underlying these interactions between macrophages and tumor cells that lead to cancer metastasis remain elusive. Previous studies have found microRNAs (miRNAs) circulating in the peripheral blood and have identified microvesicles, or exosomes, as mediators of cell-cell communication. Therefore, one alternative mechanism for the promotion of breast cancer cell invasion by TAMs may be through macrophage-secreted exosomes, which would deliver invasion-potentiating miRNAs to breast cancer cells. Results We utilized a co-culture system with IL-4-activated macrophages and breast cancer cells to verify that miRNAs are transported from macrophages to breast cancer cells. The shuttling of fluorescently-labeled exogenous miRNAs from IL-4-activated macrophages to co-cultivated breast cancer cells without direct cell-cell contact was observed. miR-223, a miRNA specific for IL-4-activated macrophages, was detected within the exosomes released by macrophages and was significantly elevated in the co-cultivated SKBR3 and MDA-MB-231 cells. The invasiveness of the co-cultivated breast cancer cells decreased when the IL-4-activated macrophages were treated with a miR-223 antisense oligonucleotide (ASO) that would inhibit miR-223 expression. Furthermore, results from a functional assay revealed that miR-223 promoted the invasion of breast cancer cells via the Mef2c-?-catenin pathway. Conclusions We conclude that macrophages regulate the invasiveness of breast cancer cells through exosome-mediated delivery of oncogenic miRNAs. Our data provide insight into the mechanisms underlying the metastasis-promoting interactions between macrophages and breast cancer cells. PMID:21939504

2011-01-01

244

Alterations in marginal zone macrophages and marginal zone B cells in old mice.  

PubMed

Marginal zones (MZs) are architecturally organized for clearance of and rapid response against blood-borne Ags entering the spleen. MZ macrophages (MZMs) and MZ B cells are particularly important in host defense against T-independent pathogens and may be crucial for the prevention of diseases, such as streptococcal pneumonia, that are devastating in older patients. Our objective was to determine whether there are changes in the cellular components of the MZ between old and young mice. Using immunocytochemistry and a blinded scoring system, we observed gross architectural changes in the MZs of old mice, including reduction in the abundance of MZMs surrounding the MZ sinus as well as disruptions in positioning of mucosal addressin cell adhesion molecule 1 (MAdCAM-1)(+) sinus lining cells and metallophilic macrophages. Loss of frequency of MZMs was corroborated by flow cytometry. A majority of old mice also showed reduced frequency of MZ B cells, which correlated with decreased abundance of MZM in individual old mice. The spleens of old mice showed less deposition of intravenously injected dextran particles within the MZ, likely because of the decreased frequency in MZMs, because SIGN-R1 expression was not reduced on MZM from old mice. The phagocytic ability of individual MZMs was examined using Staphylococcus aureus bioparticles, and no differences in phagocytosis were found between macrophages from young or old spleens. In summary, an anatomical breakdown of the MZ occurs in advanced age, and a reduction in frequency of MZM may affect the ability of the MZM compartment to clear blood-borne Ags and mount proper T-independent immune responses. PMID:21307289

Birjandi, Shirin Z; Ippolito, Jill A; Ramadorai, Anand K; Witte, Pamela L

2011-03-15

245

Alterations in Marginal Zone Macrophages and Marginal Zone B Cells in Old Mice  

PubMed Central

Marginal zones (MZs) are architecturally organized for clearance of and rapid response against blood-borne Ags entering the spleen. MZ macrophages (MZMs) and MZ B cells are particularly important in host defense against T-independent pathogens and may be crucial for the prevention of diseases, such as streptococcal pneumonia, that are devastating in older patients. Our objective was to determine whether there are changes in the cellular components of the MZ between old and young mice. Using immunocytochemistry and a blinded scoring system, we observed gross architectural changes in the MZs of old mice, including reduction in the abundance of MZMs surrounding the MZ sinus as well as disruptions in positioning of mucosal addressin cell adhesion molecule 1 (MAdCAM-1)+ sinus lining cells and metallophilic macrophages. Loss of frequency of MZMs was corroborated by flow cytometry. A majority of old mice also showed reduced frequency of MZ B cells, which correlated with decreased abundance of MZM in individual old mice. The spleens of old mice showed less deposition of intravenously injected dextran particles within the MZ, likely because of the decreased frequency in MZMs, because SIGN-R1 expression was not reduced on MZM from old mice. The phagocytic ability of individual MZMs was examined using Staphylococcus aureus bioparticles, and no differences in phagocytosis were found between macrophages from young or old spleens. In summary, an anatomical breakdown of the MZ occurs in advanced age, and a reduction in frequency of MZM may affect the ability of the MZM compartment to clear blood-borne Ags and mount proper T-independent immune responses. PMID:21307289

Birjandi, Shirin Z.; Ippolito, Jill A.; Ramadorai, Anand K.; Witte, Pamela L.

2012-01-01

246

Tetherin Can Restrict Cell-Free and Cell-Cell Transmission of HIV from Primary Macrophages to T Cells  

PubMed Central

Bst-2/Tetherin inhibits the release of HIV by tethering newly formed virus particles to the plasma membrane of infected cells. Although the mechanisms of Tetherin-mediated restriction are increasingly well understood, the biological relevance of this restriction in the natural target cells of HIV is unclear. Moreover, whether Tetherin exerts any restriction on the direct cell-cell spread of HIV across intercellular contacts remains controversial. Here we analyse the restriction endogenous Tetherin imposes on HIV transmission from primary human macrophages, one of the main targets of HIV in vivo. We find that the mRNA and protein levels of Tetherin in macrophages are comparable to those in T cells from the same donors, and are highly upregulated by type I interferons. Improved immunocytochemistry protocols enable us to demonstrate that Tetherin localises to the cell surface, the trans-Golgi network, and the macrophage HIV assembly compartments. Tetherin retains budded virions in the assembly compartments, thereby impeding the release and cell-free spread of HIV, but it is not required for the maintenance of these compartments per se. Notably, using a novel assay to quantify cell-cell spread, we show that Tetherin promotes the transfer of virus clusters from macrophages to T cells and thereby restricts the direct transmission of a dual-tropic HIV-1. Kinetic analyses provide support for the notion that this direct macrophage-T cell spread is mediated, at least in part, by so-called virological synapses. Finally, we demonstrate that the viral Vpu protein efficiently downregulates the cell surface and overall levels of Tetherin, and thereby abrogates this HIV restriction in macrophages. Together, our study shows that Tetherin, one of the most potent HIV restriction factors identified to date, can inhibit virus spread from primary macrophages, regardless of the mode of transmission. PMID:24991932

Giese, Sebastian; Marsh, Mark

2014-01-01

247

Reciprocal interactions between endothelial cells and macrophages in angiogenic vascular niches  

SciTech Connect

The ability of macrophages to promote vascular growth has been associated with the secretion and local delivery of classic proangiogenic factors (e.g., VEGF-A and proteases). More recently, a series of studies have also revealed that physical contact of macrophages with growing blood vessels coordinates vascular fusion of emerging sprouts. Interestingly, the interactions between macrophages and vascular endothelial cells (ECs) appear to be bidirectional, such that activated ECs also support the expansion and differentiation of proangiogenic macrophages from myeloid progenitors. Here, we discuss recent findings suggesting that dynamic angiogenic vascular niches might also exist in vivo, e.g. in tumors, where sprouting blood vessels and immature myeloid cells like monocytes engage in heterotypic interactions that are required for angiogenesis. Finally, we provide an account of emerging mechanisms of cell-to-cell communication that rely on secreted microvesicles, such as exosomes, which can offer a vehicle for the rapid exchange of molecules and genetic information between macrophages and ECs engaged in angiogenesis. -- Highlights: • Macrophages promote angiogenesis by secreting proangiogenic factors. • Macrophages modulate angiogenesis via cell-to-cell contacts with endothelial cells. • Endothelial cells promote the differentiation of proangiogenic macrophages. • Macrophages and endothelial cells may cooperate to form angiogenic vascular niches.

Baer, Caroline; Squadrito, Mario Leonardo [The Swiss Institute for Experimental Cancer Research (ISREC), School of Life Sciences, Swiss Federal Institute of Technology Lausanne (EPFL), 1015 Lausanne (Switzerland); Iruela-Arispe, M. Luisa, E-mail: arispe@mcdb.ucla.edu [The Swiss Institute for Experimental Cancer Research (ISREC), School of Life Sciences, Swiss Federal Institute of Technology Lausanne (EPFL), 1015 Lausanne (Switzerland); Department of Molecular, Cell and Developmental Biology and Molecular Biology Institute, University of California, Los Angeles 90095, CA (United States); De Palma, Michele, E-mail: michele.depalma@epfl.ch [The Swiss Institute for Experimental Cancer Research (ISREC), School of Life Sciences, Swiss Federal Institute of Technology Lausanne (EPFL), 1015 Lausanne (Switzerland)

2013-07-01

248

Development and function of human innate immune cells in a humanized mouse model  

PubMed Central

Mice repopulated with human hematopoietic cells are a powerful tool for the study of human hematopoiesis and immune function in vivo. However, existing humanized mouse models are unable to support development of human innate immune cells, including myeloid cells and NK cells. Here we describe a mouse strain, called MI(S)TRG, in which human versions of four genes encoding cytokines important for innate immune cell development are knocked in to their respective mouse loci. The human cytokines support the development and function of monocytes/macrophages and natural killer cells derived from human fetal liver or adult CD34+ progenitor cells injected into the mice. Human macrophages infiltrated a human tumor xenograft in MI(S)TRG mice in a manner resembling that observed in tumors obtained from human patients. This humanized mouse model may be used to model the human immune system in scenarios of health and pathology, and may enable evaluation of therapeutic candidates in an in vivo setting relevant to human physiology. PMID:24633240

Rongvaux, Anthony; Willinger, Tim; Martinek, Jan; Strowig, Till; Gearty, Sofia V.; Teichmann, Lino L.; Saito, Yasuyuki; Marches, Florentina; Halene, Stephanie; Palucka, A. Karolina; Manz, Markus G.; Flavell, Richard A.

2014-01-01

249

Smac mimetics induce inflammation and necrotic tumour cell death by modulating macrophage activity  

PubMed Central

Smac mimetics (SMs) comprise a class of small molecules that target members of the inhibitor of apoptosis family of pro-survival proteins, whose expression in cancer cells hinders the action of conventional chemotherapeutics. Herein, we describe the activity of SM83, a newly synthesised dimeric SM, in two cancer ascites models: athymic nude mice injected intraperitoneally with IGROV-1 human ovarian carcinoma cells and immunocompetent BALB/c mice injected with murine Meth A sarcoma cells. SM83 rapidly killed ascitic IGROV-1 and Meth A cells in vivo (prolonging mouse survival), but was ineffective against the same cells in vitro. IGROV-1 cells in nude mice were killed within the ascites by a non-apoptotic, tumour necrosis factor (TNF)-dependent mechanism. SM83 administration triggered a rapid inflammatory event characterised by host secretion of TNF, interleukin-1? and interferon-?. This inflammatory response was associated with the reversion of the phenotype of tumour-associated macrophages from a pro-tumoural M2- to a pro-inflammatory M1-like state. SM83 treatment was also associated with a massive recruitment of neutrophils that, however, was not essential for the antitumoural activity of this compound. In BALB/c mice bearing Meth A ascites, SM83 treatment was in some cases curative, and these mice became resistant to a second injection of cancer cells, suggesting that they had developed an adaptive immune response. Altogether, these results indicate that, in vivo, SM83 modulates the immune system within the tumour microenvironment and, through its pro-inflammatory action, leads cancer cells to die by necrosis with the release of high-mobility group box-1. In conclusion, our work provides evidence that SMs could be more therapeutically active than expected by stimulating the immune system. PMID:24232096

Lecis, D; De Cesare, M; Perego, P; Conti, A; Corna, E; Drago, C; Seneci, P; Walczak, H; Colombo, M P; Delia, D; Sangaletti, S

2013-01-01

250

Diet Modifies the Neuroimmune System by Influencing Macrophage Activation  

ERIC Educational Resources Information Center

It has long been appreciated that adequate nutrition is required for proper immune function and it is now recognized that dietary components contribute to modulation of immune cells, subsequently impacting the whole body's response during an immune challenge. Macrophage activation plays a critical role in the immune system and directs the…

Sherry, Christina Lynn

2009-01-01

251

Macrophage recognition of cells with elevated calcium is mediated by carbohydrate chains of CD43.  

PubMed

Macrophages remove deteriorating cells (those undergoing apoptosis and oxidation) via poly-N-acetyllactosaminyl chains on CD43 caps, a major cell-surface glycoprotein. Unusually high intracellular calcium levels are also deteriorating for cells and tissue. Here we artificially elevated calcium levels in cells and examined the mechanism by which this elevation was resolved by macrophages. Results showed that treatment with the calcium ionophore A23187 and ionomycin induces capping of CD43 on Jurkat cells, which are subsequently recognized and phagocytosed by macrophages, indicating that macrophages regard cells with elevated calcium as targets for removal. Further tests showed that A23187- and ionomycin-treated Jurkat cells did not induce apoptotic changes such as DNA fragmentation or phosphatidylserine expression, indicating that these cells were removed despite still being viable. Jurkat cells pretreated with anti-CD43 antibody or those with poly-N-acetyllactosaminyl chains containing oligosaccharides inhibited macrophage binding, indicating that macrophages recognize the poly-N-acetyllactosaminyl chains on CD43. Binding was also inhibited by treating macrophages with anti-nucleolin antibody, indicating that recognition occurs through nucleolin, a cell-surface receptor. Further, nucleolin-transfected HEK293 cells bound A23187-treated cells, and this binding was inhibited by in the presence of oligosaccharides. Taken together, these results show that elevated calcium levels induce CD43 capping, and macrophages remove the cells if their nucleolin receptors can bind to the poly-N-acetyllactosaminyl chains of capped CD43. PMID:23400223

Miki, Yuichi; Oguri, Emiri; Hirano, Kazuya; Beppu, Masatoshi

2013-01-01

252

An efferocytosis-induced, IL-4-dependent macrophage-iNKT cell circuit suppresses sterile inflammation and is defective in murine CGD.  

PubMed

Efferocytosis of apoptotic neutrophils by macrophages following tissue injury is fundamental to the resolution of inflammation and initiation of tissue repair. Using a sterile peritonitis model in mice, we identified interleukin (IL)-4-producing efferocytosing macrophages in the peritoneum that activate invariant natural killer T (iNKT) cells to produce cytokines including IL-4, IL-13, and interferon-?. Importantly, IL-4 from macrophages contributes to alternative activation of peritoneal exudate macrophages and augments type 2 cytokine production from NKT cells to suppress inflammation. The increased peritonitis in mice deficient in IL-4, NKT cells, or IL-4R? expression on myeloid cells suggested that each is a key component for resolution of sterile inflammation. The reduced NAD phosphate oxidase is also critical for this model, because in mice with X-linked chronic granulomatous disease (X-CGD) that lack oxidase subunits, activation of iNKT cells by X-CGD peritoneal exudate macrophages was impaired during sterile peritonitis, resulting in enhanced and prolonged inflammation in these mice. Therefore, efferocytosis-induced IL-4 production and activation of IL-4-producing iNKT cells by macrophages are immunomodulatory events in an innate immune circuit required to resolve sterile inflammation and promote tissue repair. PMID:23426944

Zeng, Melody Yue; Pham, Duy; Bagaitkar, Juhi; Liu, Jianyun; Otero, Karel; Shan, Ming; Wynn, Thomas A; Brombacher, Frank; Brutkiewicz, Randy R; Kaplan, Mark H; Dinauer, Mary C

2013-04-25

253

An efferocytosis-induced, IL-4-dependent macrophage-iNKT cell circuit suppresses sterile inflammation and is defective in murine CGD  

PubMed Central

Efferocytosis of apoptotic neutrophils by macrophages following tissue injury is fundamental to the resolution of inflammation and initiation of tissue repair. Using a sterile peritonitis model in mice, we identified interleukin (IL)-4–producing efferocytosing macrophages in the peritoneum that activate invariant natural killer T (iNKT) cells to produce cytokines including IL-4, IL-13, and interferon-?. Importantly, IL-4 from macrophages contributes to alternative activation of peritoneal exudate macrophages and augments type 2 cytokine production from NKT cells to suppress inflammation. The increased peritonitis in mice deficient in IL-4, NKT cells, or IL-4R? expression on myeloid cells suggested that each is a key component for resolution of sterile inflammation. The reduced NAD phosphate oxidase is also critical for this model, because in mice with X-linked chronic granulomatous disease (X-CGD) that lack oxidase subunits, activation of iNKT cells by X-CGD peritoneal exudate macrophages was impaired during sterile peritonitis, resulting in enhanced and prolonged inflammation in these mice. Therefore, efferocytosis-induced IL-4 production and activation of IL-4–producing iNKT cells by macrophages are immunomodulatory events in an innate immune circuit required to resolve sterile inflammation and promote tissue repair. PMID:23426944

Zeng, Melody Yue; Pham, Duy; Bagaitkar, Juhi; Liu, Jianyun; Otero, Karel; Shan, Ming; Wynn, Thomas A.; Brombacher, Frank; Brutkiewicz, Randy R.; Kaplan, Mark H.

2013-01-01

254

Mast Cell Regulation of the Immune Response  

PubMed Central

Mast cells are well known as principle effector cells of type I hypersensitivity responses. Beyond this role in allergic disease, these cells are now appreciated as playing an important role in many inflammatory conditions. This review summarizes the support for mast cell involvement in resisting bacterial infection, exacerbating autoimmunity and atherosclerosis, and promoting cancer progression. A commonality in these conditions is the ability of mast cells to elicit migration of many cell types, often through the production of inflammatory cytokines such as tumor necrosis factor. However, recent data also demonstrates that mast cells can suppress the immune response through interleukin-10 production. The data encourage those working in this field to expand their view of how mast cells contribute to immune homeostasis. PMID:23283207

2009-01-01

255

Adipose Tissue Macrophages Function As Antigen-Presenting Cells and Regulate Adipose Tissue CD4+ T Cells in Mice  

PubMed Central

The proinflammatory activation of leukocytes in adipose tissue contributes to metabolic disease. How crosstalk between immune cells initiates and sustains adipose tissue inflammation remains an unresolved question. We have examined the hypothesis that adipose tissue macrophages (ATMs) interact with and regulate the function of T cells. Dietary obesity was shown to activate the proliferation of effector memory CD4+ T cells in adipose tissue. Our studies further demonstrate that ATMs are functional antigen-presenting cells that promote the proliferation of interferon-?–producing CD4+ T cells in adipose tissue. ATMs from lean and obese visceral fat process and present major histocompatibility complex (MHC) class II–restricted antigens. ATMs were sufficient to promote proliferation and interferon-? production from antigen-specific CD4+ T cells in vitro and in vivo. Diet-induced obesity increased the expression of MHC II and T-cell costimulatory molecules on ATMs in visceral fat, which correlated with an induction of T-cell proliferation in that depot. Collectively, these data indicate that ATMs provide a functional link between the innate and adaptive immune systems within visceral fat in mice. PMID:23493569

Morris, David L.; Cho, Kae Won; DelProposto, Jennifer L.; Oatmen, Kelsie E.; Geletka, Lynn M.; Martinez-Santibanez, Gabriel; Singer, Kanakadurga; Lumeng, Carey N.

2013-01-01

256

Effect of interaction of vitamin C on macrophage immune response to infection with Mycobacterium bovis.  

PubMed

Bovine tuberculosis is a chronic infectious disease caused by Mycobacterium bovis affecting humans and livestock. Like Mycobacterium tuberculosis (M.tb), M. bovis can persist in cattle without causing overt symptoms after entering a non-replicating persistent (NRP) state. Given that M.tb enters NRP under stress conditions, we sought to find the effects of vitamin C (VC) on M. bovis in vitro and in vivo (VC could mimic stresses like hypoxia by O2 scavenging and acidic conditions in phagosome). M. bovis was cultured in a medium with VC for 48 h. The differential expression of five genes (dosR, dosS, dosT, icl, and hspX of M. bovis) implicated in the M. bovis NRP state was measured with real-time quantitative PCR. Expression of all five genes was increased by VC. Relative to the control, VC-exposed bacteria appeared smaller and more rounded in shape with a much thicker inner envelope. A lower number of viable bacteria were found in comparison with those of the control. We infected macrophage cell line ANA-1 with M. bovis and cultured it in VC-added medium (MC group) for 24h and 48 h. Expression of il-10, il-6, tnf-?, and il-? was examined and compared with expression by cells infected by M. bovis only without VC treatment (MB group), uninfected cells in the medium treated with VC (VC group), and cells in the medium only without VC. Il-1?, tnf-?, and il-6 transcription were up-regulated significantly in MC group. IL-10 gene expression in MB and MC groups was less than in the control at 24h, but that of MC group increased more than the MB group at 48 h. The numbers of intracellular M. bovis in the MC group were lower than that in the other groups. Slower growth was found in VC-treated M. bovis, and macrophages were more bactericidal for intracellular VC-stimulated M. bovis than for M. bovis with no VC treatment. PMID:22762523

Wang, J; Zhou, X; Zhang, Z; Xu, L; Yin, X; Yang, L; Zhao, D

2012-01-01

257

Electrochemical biosensors for on-chip detection of oxidative stress from immune cells  

PubMed Central

Seamless integration of biological components with electrochemical sensors is critical in the development of microdevices for cell analysis. The present paper describes the integration miniature Au electrodes next to immune cells (macrophages) in order to detect cell-secreted hydrogen peroxide (H2O2). Photopatterning of poly(ethylene glycol) (PEG) hydrogels was used to both immobilize horseradish peroxidase molecules onto electrodes and to define regions for cell attachment in the vicinity of sensing electrodes. Electrodes micropatterned in such a manner were enclosed inside poly(dimethylsiloxane) fluid conduits and incubated with macrophages. The cells attached onto the exposed glass regions in the vicinity of the electrodes and nowhere else on the non-fouling PEG hydrogel surface. A microfluidic device was converted into an electrochemical cell by placing flow-through Ag?AgCl reference and Pt wire counter electrodes at the outlet and inlet, respectively. This microdevice with integrated H2O2-sensing electrodes had sensitivity of 27 ?A?cm2 mM with a limit of detection of 2 ?M. Importantly, this microdevice allowed controllable seeding of macrophages next to electrodes, activation of these cells and on-chip monitoring of H2O2 release in real time. In the future, this biosensor platform may be utilized for monitoring of macrophage responses to pathogens or for the study of inflammatory signaling in micropatterned cell cultures. PMID:22007269

Yan, Jun; Pedrosa, Valber A.; Enomoto, James; Simonian, Aleksandr L.; Revzin, Alexander

2011-01-01

258

Selection of multipotent cells and enhanced muscle reconstruction by myogenic macrophage-secreted factors  

Microsoft Academic Search

Skeletal muscle regeneration relies on satellite cells, a population of myogenic precursors. Inflammation also plays a determinant role in the process, as upon injury, macrophages are attracted by the damaged myofibers and the activated satellite cells and act as key elements of dynamic muscle supportive stroma. Yet, it is not known how macrophages interact with the more profound stem cells

Alberto Malerba; Libero Vitiello; Daniela Segat; Emanuela Dazzo; Marco Frigo; Ilaria Scambi; Paolo De Coppi; Luisa Boldrin; Laura Martelli; Alessandra Pasut; Chiara Romualdi; Rosa Grazia Bellomo; Jacopo Vecchiet; Maurizio David Baroni

2009-01-01

259

Ultrastructural studies of spontaneously regressing plane warts. Macrophages attack verruca-epidermal cells  

Microsoft Academic Search

Plane warts were examined at the earliest phase of spontaneous involution using an electron microscopy. Macrophages outnumbered lymphocytes in invading the epidermis. Lymphocytes exhibited pseudopods on the surface which occasionally reached into the epidermal cells. The cell membranes of both macrophages and epidermal cells frequently disappeared on the contacting surface and on occasion part of the cytoplasm and even the

Motoi Oguchi; Jinro Komura; Hachiro Tagami; Shigeo Ofuji

1981-01-01

260

Cell Host & Microbe Leishmania Evades Host Immunity  

E-print Network

Cell Host & Microbe Article Leishmania Evades Host Immunity by Inhibiting Antigen Cross cells engulf microorganisms at sites of infection, leads to the formation of phagosomes, where microbes of the microbicidal properties required for the killing of microbes (Desjardins et al., 2005; Jutras and Desjardins

Arnold, Jonathan

261

molecular genetic assessment of chicken macrophage innate immunity: toll-like receptors, mechanisms of action, and kinetic transcriptome profile  

Microsoft Academic Search

Understanding the genetic regulation of host response governing disease resistance mechanisms is of primary importance for improving animal health and food safety. Many of the biological characteristics of the chicken make it an ideal organism for studies in immunology, evolution, agriculture, medicine and comparative functional analyses. Different cell lines or primary cells from the immune system generate different immune responses

Ceren Ciraci

2010-01-01

262

Enterococcus faecalis Infection Activates Phosphatidylinositol 3-Kinase Signaling To Block Apoptotic Cell Death in Macrophages.  

PubMed

Apoptosis is an intrinsic immune defense mechanism in the host response to microbial infection. Not surprisingly, many pathogens have evolved various strategies to manipulate this important pathway to benefit their own survival and dissemination in the host during infection. To our knowledge, no attempts have been made to explore the host cell survival signals modulated by the bacterium Enterococcus faecalis. Here, we show for the first time that during early stages of infection, internalized enterococci can prevent host cell (RAW264.7 cells, primary macrophages, and mouse embryonic fibroblasts [MEFs]) apoptosis induced by a wide spectrum of proapoptotic stimuli. Activation of caspase 3 and cleavage of the caspase 3 substrate poly(ADP-ribose) polymerase were inhibited in E. faecalis-infected cells, indicating that E. faecalis protects macrophages from apoptosis by inhibiting caspase 3 activation. This antiapoptotic activity in E. faecalis-infected cells was dependent on the activation of the phosphatidylinositol 3-kinase (PI3K)/Akt signaling pathway, which resulted in the increased expression of the antiapoptotic factor Bcl-2 and decreased expression of the proapoptotic factor Bax. Further analysis revealed that active E. faecalis physiology was important for inhibition of host cell apoptosis, and this feature seemed to be a strain-independent trait among E. faecalis isolates. Employing a mouse peritonitis model, we also determined that cells collected from the peritoneal lavage fluid of E. faecalis-infected mice showed reduced levels of apoptosis compared to cells from uninfected mice. These results show early modulation of apoptosis during infection and have important implications for enterococcal pathogenesis. PMID:25267834

Zou, Jun; Shankar, Nathan

2014-12-01

263

Increased malignancy of oral squamous cell carcinomas (oscc) is associated with macrophage polarization in regional lymph nodes – an immunohistochemical study  

PubMed Central

Background It is largely accepted that specific immunological parameters in solid malignancies are associated with patient’s prognosis. Recently a correlation of macrophage polarization with histomorphological parameters could also be shown in oral squamous cell carcinoma (oscc). The observed tumor derived peripheral immune tolerance could be associated with the macrophage polarization in regional tumor draining lymph nodes. So far there are no studies analyzing the macrophage polarization in cervical lymph nodes of oscc patients. In the present study we aimed to correlate macrophage polarization in different anatomical lymph node compartments of patients diagnosed with oscc with histopathologic parameters of the primary tumor (T-, N-, L-, V-, Pn-status, grading). Methods Tumor free (n?=?37) and metastatic (n?=?17) lymph nodes of T1 and T2 oscc patients were processed for immunohistochemistry to detect CD68, CD11c, CD163 and MRC1 positive cells. Samples were digitized using whole slide imaging and the number of cells expressing the aforementioned markers in the region of interest quantitatively analyzed. Results The malignancy of the primary tumor (defined by T-, L-, Pn-status, grading) correlated with the lymph node macrophage polarization. L1 and Pn1 tumor cases displayed a significantly (p?macrophage polarization. Conclusions The current study revealed for the first time an influence of oscc on the macrophage polarization in regional lymph nodes. Markers of malignant behavior in the primary tumor were associated with a shift of macrophage polarization in lymph nodes from the anti-tumoral M1 type to the tumor-promoting M2 type. As tumor free and metastatic lymph nodes did not differ in terms of their macrophage polarization pattern, there must be other factors influencing the location for lymph node metastasis formation. PMID:25042135

2014-01-01

264

Global Transcriptome Analysis of Staphylococcus aureus Biofilms in Response to Innate Immune Cells  

PubMed Central

The potent phagocytic and microbicidal activities of neutrophils and macrophages are among the first lines of defense against bacterial infections. Yet Staphylococcus aureus is often resistant to innate immune defense mechanisms, especially when organized as a biofilm. To investigate how S. aureus biofilms respond to macrophages and neutrophils, gene expression patterns were profiled using Affymetrix microarrays. The addition of macrophages to S. aureus static biofilms led to a global suppression of the biofilm transcriptome with a wide variety of genes downregulated. Notably, genes involved in metabolism, cell wall synthesis/structure, and transcription/translation/replication were among the most highly downregulated, which was most dramatic at 1 h compared to 24 h following macrophage addition to biofilms. Unexpectedly, few genes were enhanced in biofilms after macrophage challenge. Unlike coculture with macrophages, coculture of S. aureus static biofilms with neutrophils did not greatly influence the biofilm transcriptome. Collectively, these experiments demonstrate that S. aureus biofilms differentially modify their gene expression patterns depending on the leukocyte subset encountered. PMID:24042108

Scherr, Tyler D.; Roux, Christelle M.; Hanke, Mark L.; Angle, Amanda; Dunman, Paul M.

2013-01-01

265

Mechanism of Suppression of Cell-Mediated Immunity by Measles Virus  

Microsoft Academic Search

The mechanisms underlying the profound suppression of cell-mediated immunity (CMI) accompanying measles are unclear. Interleukin-12 (IL-12), derived principally from monocytes and macrophages, is critical for the generation of CMI. Measles virus (MV) infection of primary human monocytes specifically down-regulated IL-12 production. Cross-linking of CD46, a complement regulatory protein that is the cellular receptor for MV, with antibody or with the

Christopher L. Karp; Maria Wysocka; Larry M. Wahl; Joseph M. Ahearn; Peter J. Cuomo; Barbara Sherry; Giorgio Trinchieri; Diane E. Griffin

1996-01-01

266

Depression of afferent arc of the in vivo cytotoxic T-cell immunity by bacterial lipopolysaccharides  

SciTech Connect

The afferent arc of the in vivo cytotoxic T-cell immunity assessed by second set rejection of ascitic allogeneic tumors was shown to be depressed by bacterial lipopolysaccharide (LPS) that was administered simultaneously with or 1 day before injection of allogeneic spleen cells as stimulators. Two different LPSs from Escherichia coli O55 and Klebsiella O3 displayed similar activities whereas dextran sulfate, concanavalin A, or poly A:U was not effective. Stimulator activities of allogeneic cells was not directly modified by LPS. Any definite suppressor activity on afferent or efferent arc of the T-cell response was not demonstrable in mice receiving LPS and allogeneic cells. Further, the LPS effect for immune depression was not diminished by whole body X-ray irradiation to the recipient at 300 R, which ablated the B-cell reactivity to LPS for polyclonal activation, or by treatment of the recipient with carrageenan, a known toxic agent to macrophages. It was suggested from these results that LPS suppresses the cytotoxic T-cell immunity by modulating responder T cells to be temporarily refractory to the allogeneic stimulus rather than by activating suppressor cells such as radiation-sensitive lymphocytes and carrageenan-sensitive macrophages.

Mizoguchi, K.; Nakashima, I.; Hasegawa, Y.; Isobe, K.; Kato, N.; Shimokata, K.; Kawashima, K.; Nagase, F.; Ando, K.; Yoshida, T.

1985-10-15

267

Regulation of angiogenesis, mural cell recruitment and adventitial macrophage behavior by Toll-like receptors.  

PubMed

The angiogenic response to injury can be studied by culturing rat or mouse aortic explants in collagen gels. Gene expression studies show that aortic angiogenesis is preceded by an immune reaction with overexpression of Toll-like receptors (TLRs) and TLR-inducible genes. TLR1, 3, and 6 are transiently upregulated at 24 h whereas TLR2, 4, and 8 expression peaks at 24 h but remains elevated during angiogenesis and vascular regression. Expression of TLR5, 7 and 9 steadily increases over time and is highest during vascular regression. Studies with isolated cells show that TLRs are expressed at higher levels in aortic macrophages compared to endothelial or mural cells with the exception of TLR2 and TLR9 which are more abundant in the aortic endothelium. LPS and other TLR ligands dose dependently stimulate angiogenesis and vascular endothelial growth factor production. TLR9 ligands also influence the behavior of nonendothelial cell types by blocking mural cell recruitment and inducing formation of multinucleated giant cells by macrophages. TLR9-induced mural cell depletion is associated with reduced expression of the mural cell recruiting factor PDGFB. The spontaneous angiogenic response of the aortic rings to injury is reduced in cultures from mice deficient in myeloid differentiation primary response 88 (MyD88), a key adapter molecule of TLRs, and following treatment with an inhibitor of the NF?B pathway. These results suggest that the TLR system participates in the angiogenic response of the vessel wall to injury and may play an important role in the regulation of inflammatory angiogenesis in reactive and pathologic processes. PMID:24091496

Aplin, Alfred C; Ligresti, Giovanni; Fogel, Eric; Zorzi, Penelope; Smith, Kelly; Nicosia, Roberto F

2014-01-01

268

Activated Human Mast Cells Induce LOX-1-Specific Scavenger Receptor Expression in Human Monocyte-Derived Macrophages  

PubMed Central

Objective Activated mast cells in atherosclerotic lesions degranulate and release bioactive compounds capable of regulating atherogenesis. Here we examined the ability of activated human primary mast cells to regulate the expression of the major scavenger receptors in cultured human primary monocyte-derived macrophages (HMDMs). Results Components released by immunologically activated human primary mast cells induced a transient expression of lectin-like oxidized LDL receptor (LOX-1) mRNA in HMDMs, while the expression of two other scavenger receptors, MSR1 and CD36, remained unaffected. The LOX-1-inducing secretory components were identified as histamine, tumor necrosis factor alpha (TNF-?), and transforming growth factor beta (TGF-?1), which exhibited a synergistic effect on LOX-1 mRNA expression. Histamine induced a transient expression of LOX-1 protein. Mast cell –induced increase in LOX-1 expression was not associated with increased uptake of oxidized LDL by the macrophages. Conclusions Mast cell-derived histamine, TNF-?, and TGF-?1 act in concert to induce a transient increase in LOX-1 expression in human primary monocyte-derived macrophages. The LOX-1-inducing activity potentially endows mast cells a hitherto unrecognized role in the regulation of innate immune reactions in atherogenesis. PMID:25250731

Alanne-Kinnunen, Mervi; Lappalainen, Jani; Oorni, Katariina; Kovanen, Petri T.

2014-01-01

269

Irritant-induced migration of Langerhans cells coincides with an IL-10-dependent switch to a macrophage-like phenotype.  

PubMed

Langerhans cells (LCs) migrate after topical exposure of the skin to irritants, despite the supposed independence of irritant contact dermatitis from adaptive immunity. Whereas allergen-activated LCs are known to migrate to the draining lymph nodes (LNs), the fate of migrated LCs upon topical irritant exposure is unknown. Here, we identified a phenotypic switch of LCs after their migration into the dermis upon irritant exposure. With the aid of ex vivo intact human skin and epidermal sheets, we show that dermal fibroblasts are necessary for an IL-10-dependent postmigrational phenotypic switch of LCs into macrophage-like cells. Exposure of ex vivo skin to a panel of seven irritants resulted in a decrease in the number of CD1a(+) cells and an increase in CD14(+)/CD68(+) cells in the dermis. Neutralizing antibodies against IL-10 totally inhibited the phenotypic LC-to-macrophage transition, but did not influence the migration of CD1a(+) cells. Exposure of epidermal sheets to irritants resulted in a fibroblast-dependent LC-to-CD14(+)/CD68(+) switch coinciding with migration, which could be totally inhibited by neutralizing antibodies against either IL-10 or CCL2/CCL5 (two chemokines responsible for epidermal-to-dermal migration). We have thus identified an IL-10-dependent phenotypic switch of LCs into macrophage-like cells upon irritant exposure and emigration from the epidermis. PMID:21068755

Ouwehand, Krista; Oosterhoff, Dinja; Breetveld, Melanie; Scheper, Rik J; de Gruijl, Tanja D; Gibbs, Susan

2011-02-01

270

Paneth cell ?-defensins in enteric innate immunity  

Microsoft Academic Search

Paneth cells at the base of small intestinal crypts of Lieberkühn secrete high levels of ?-defensins in response to cholinergic\\u000a and microbial stimuli. Paneth cell ?-defensins are broad spectrum microbicides that function in the extracellular environment\\u000a of the intestinal lumen, and they are responsible for the majority of secreted bactericidal peptide activity. Paneth cell\\u000a ?-defensins confer immunity to oral infection

André Joseph Ouellette; Springer Basel AG

2011-01-01

271

Trichomonas vaginalis homolog of macrophage migration inhibitory factor induces prostate cell growth, invasiveness, and inflammatory responses.  

PubMed

The human-infective parasite Trichomonas vaginalis causes the most prevalent nonviral sexually transmitted infection worldwide. Infections in men may result in colonization of the prostate and are correlated with increased risk of aggressive prostate cancer. We have found that T. vaginalis secretes a protein, T. vaginalis macrophage migration inhibitory factor (TvMIF), that is 47% similar to human macrophage migration inhibitory factor (HuMIF), a proinflammatory cytokine. Because HuMIF is reported to be elevated in prostate cancer and inflammation plays an important role in the initiation and progression of cancers, we have explored a role for TvMIF in prostate cancer. Here, we show that TvMIF has tautomerase activity, inhibits macrophage migration, and is proinflammatory. We also demonstrate that TvMIF binds the human CD74 MIF receptor with high affinity, comparable to that of HuMIF, which triggers activation of ERK, Akt, and Bcl-2-associated death promoter phosphorylation at a physiologically relevant concentration (1 ng/mL, 80 pM). TvMIF increases the in vitro growth and invasion through Matrigel of benign and prostate cancer cells. Sera from patients infected with T. vaginalis are reactive to TvMIF, especially in males. The presence of anti-TvMIF antibodies indicates that TvMIF is released by the parasite and elicits host immune responses during infection. Together, these data indicate that chronic T. vaginalis infections may result in TvMIF-driven inflammation and cell proliferation, thus triggering pathways that contribute to the promotion and progression of prostate cancer. PMID:24843155

Twu, Olivia; Dessí, Daniele; Vu, Anh; Mercer, Frances; Stevens, Grant C; de Miguel, Natalia; Rappelli, Paola; Cocco, Anna Rita; Clubb, Robert T; Fiori, Pier Luigi; Johnson, Patricia J

2014-06-01

272

Palmitate- and lipopolysaccharide-activated macrophages evoke contrasting insulin responses in muscle cells.  

PubMed

Factors secreted by macrophages contribute to whole body insulin resistance, acting in part on adipose tissue. Muscle is the major tissue for glucose disposal, but how macrophage-derived factors impact skeletal muscle glucose uptake is unknown, or whether the macrophage environment influences this response. We hypothesized that conditioned medium from macrophages pretreated with palmitate or LPS would directly affect insulin action and glucose uptake in muscle cells. L6-GLUT4myc myoblasts were exposed to conditioned medium from RAW 264.7 macrophages pretreated with palmitate or LPS. Conditioned medium from palmitate-treated RAW 264.7 macrophages inhibited myoblast insulin-stimulated glucose uptake, GLUT4 translocation, and Akt phosphorylation while activating JNK p38 MAPK, decreasing IkappaBalpha, and elevating inflammation markers. Surprisingly, and opposite to its effects on adipose cells, conditioned medium from LPS-treated macrophages stimulated myoblast insulin-stimulated glucose uptake, GLUT4 translocation, and Akt phosphorylation without affecting stress kinases or inflammation indexes. This medium had markedly elevated IL-10 levels, and IL-10, alone, potentiated insulin action in myoblasts and partly reversed the insulin resistance imparted by medium from palmitate-treated macrophages. IL-10 neutralizing antibodies blunted the positive influence of LPS macrophage-conditioned medium. We conclude that myoblasts and adipocytes respond differently to cytokines. Furthermore, depending on their environment, macrophages negatively or positively influence muscle cells. Macrophages exposed to palmitate produce a mixture of proinflammatory cytokines that reduce insulin action in muscle cells; conversely, LPS-activated macrophages increase insulin action, likely via IL-10. Macrophages may be an integral element in glucose homeostasis in vivo, relaying effects of circulating factors to skeletal muscle. PMID:18840759

Samokhvalov, Victor; Bilan, Phillip J; Schertzer, Jonathan D; Antonescu, Costin N; Klip, Amira

2009-01-01

273

Sertoli Cell-Specific Deletion of the Androgen Receptor Compromises Testicular Immune Privilege in Mice1  

PubMed Central

In the mammalian testis, meiotic and postmeiotic germ cell antigens are granted immune privilege. Both local immune suppression and specialized intercellular junctions between somatic Sertoli cells have been proposed to contribute to a highly restricted and effective blood-testis barrier (BTB) that helps maintain tolerance to germ cell antigens. Several studies have suggested that androgens play a role in immune suppression, although direct evidence for this is lacking. We previously reported that Sertoli cell-specific ablation of the androgen receptor (Ar) decreases expression of Cldn3, an androgen-regulated gene and component of Sertoli cell tight junctions, and increases the permeability of the BTB to biotin, a small-molecular-weight tracer. The physiological consequences of Sertoli cell-specific Ar (S-Ar) ablation on immune privilege are unknown. Here we show that in the testes of S-Ar mutant mice, the ultrastructure of Sertoli cell tight junctions is defective and testicular IgG levels are elevated. The interstitium of S-Ar mutant testes becomes populated with macrophages, neutrophils, plasma cells, and eosinophils, and serum samples of mutant mice contain antibodies against germ cell antigens. Together, these results suggest that Sertoli cell-specific deletion of the androgen receptor results in loss of testicular immune privilege. Suppressed levels of androgen signaling may be a contributing factor in idiopathic male infertility. PMID:21543771

Meng, Jing; Greenlee, Anne R.; Taub, Chloe J.; Braun, Robert E.

2011-01-01

274

Activated Macrophage Survival Is Coordinated by TAK1 Binding Proteins  

PubMed Central

Macrophages play diverse roles in tissue homeostasis and immunity, and canonically activated macrophages are critically associated with acute inflammatory responses. It is known that activated macrophages undergo cell death after transient activation in some settings, and the viability of macrophages impacts on inflammatory status. Here we report that TGF?- activated kinase (TAK1) activators, TAK1-binding protein 1 (TAB1) and TAK1-binding protein 2 (TAB2), are critical molecules in the regulation of activated macrophage survival. While deletion of Tak1 induced cell death in bone marrow derived macrophages even without activation, Tab1 or Tab2 deletion alone did not profoundly affect survival of naïve macrophages. However, in lipopolysaccharide (LPS)-activated macrophages, even single deletion of Tab1 or Tab2 resulted in macrophage death with both necrotic and apoptotic features. We show that TAB1 and TAB2 were redundantly involved in LPS-induced TAK1 activation in macrophages. These results demonstrate that TAK1 activity is the key to activated macrophage survival. Finally, in an in vivo setting, Tab1 deficiency impaired increase of peritoneal macrophages upon LPS challenge, suggesting that TAK1 complex regulation of macrophages may participate in in vivo macrophage homeostasis. Our results demonstrate that TAB1 and TAB2 are required for activated macrophages, making TAB1 and TAB2 effective targets to control inflammation by modulating macrophage survival. PMID:24736749

Mihaly, September R.; Morioka, Sho; Ninomiya-Tsuji, Jun; Takaesu, Giichi

2014-01-01

275

Ebola virus: The role of macrophages and dendritic cells in the pathogenesis of Ebola hemorrhagic fever  

Microsoft Academic Search

Ebola hemorrhagic fever is a severe viral infection characterized by fever, shock and coagulation defects. Recent studies in macaques show that major features of illness are caused by effects of viral replication on macrophages and dendritic cells. Infected macrophages produce proinflammatory cytokines, chemokines and tissue factor, attracting additional target cells and inducing vasodilatation, increased vascular permeability and disseminated intravascular coagulation.

Mike Bray; Thomas W. Geisbert

2005-01-01

276

Berberine promotes recovery of colitis and inhibits inflammatory responses in colonic macrophages and epithelial cells in DSS-treated mice  

PubMed Central

Inflammatory bowel disease (IBD) results from dysregulation of intestinal mucosal immune responses to microflora in genetically susceptible hosts. A major challenge for IBD research is to develop new strategies for treating this disease. Berberine, an alkaloid derived from plants, is an alternative medicine for treating bacterial diarrhea and intestinal parasite infections. Recent studies suggest that berberine exerts several other beneficial effects, including inducing anti-inflammatory responses. This study determined the effect of berberine on treating dextran sulfate sodium (DSS)-induced intestinal injury and colitis in mice. Berberine was administered through gavage to mice with established DSS-induced intestinal injury and colitis. Clinical parameters, intestinal integrity, proinflammatory cytokine production, and signaling pathways in colonic macrophages and epithelial cells were determined. Berberine ameliorated DSS-induced body weight loss, myeloperoxidase activity, shortening of the colon, injury, and inflammation scores. DSS-upregulated proinflammatory cytokine levels in the colon, including TNF, IFN-?, KC, and IL-17 were reduced by berberine. Berberine decreased DSS-induced disruption of barrier function and apoptosis in the colon epithelium. Furthermore, berberine inhibited proinflammatory cytokine production in colonic macrophages and epithelial cells in DSS-treated mice and promoted apoptosis of colonic macrophages. Activation of signaling pathways involved in stimulation of proinflammatory cytokine production, including MAPK and NF-?B, in colonic macrophages and epithelial cells from DSS-treated mice was decreased by berberine. In summary, berberine promotes recovery of DSS-induced colitis and exerts inhibitory effects on proinflammatory responses in colonic macrophages and epithelial cells. Thus berberine may represent a new therapeutic approach for treating gastrointestinal inflammatory disorders. PMID:22173918

Wang, Lihong; Shi, Yan; Cao, Hanwei; Liu, Liping; Washington, M. Kay; Chaturvedi, Rupesh; Israel, Dawn A.; Cao, Hailong; Wang, Bangmao; Peek, Richard M.; Wilson, Keith T.; Polk, D. Brent

2012-01-01

277

Fibrocyte-like cells recruited to the spleen support innate and adaptive immune responses to acute injury or infection  

PubMed Central

Bone marrow (BM)-derived fibrocytes are a population of CD45+ and collagen Type I-expressing cells that migrate to the spleen and to target injured organs, such as skin, lungs, kidneys, and liver. While CD45+Col+ fibrocytes contribute to collagen deposition at the site of injury, the role of CD45+Col+ cells in spleen has not been elucidated. Here, we demonstrate that hepatotoxic injury (CCl4), TGF-?1, lipopolysaccharide, or infection with Listeria monocytogenes induce rapid recruitment of CD45+Col+ fibrocyte-like cells to the spleen. These cells have a gene expression pattern that includes antimicrobial factors (myleoperoxidase, cathelicidin, and defensins) and MHC II at higher levels than found on quiescent or activated macrophages. The immune functions of these splenic CD45+Col+ fibrocyte-like cells include entrapment of bacteria into extracellular DNA-based structures containing cathelicidin and presentation of antigens to naïve CD8+ T cells to induce their proliferation. Stimulation of these splenic fibrocyte-like cells with granulocyte macrophage-colony stimulating factor or macrophage-colony stimulating factor induces downregulation of collagen expression and terminal differentiation into the dendritic cells or macrophage. Thus, splenic CD45+Col+ cells are a population of rapidly mobilized BM-derived fibrocyte-like cells that respond to inflammation or infection to participate in innate and adaptive immune responses. PMID:21499735

von Köckritz-Blickwede, Maren; Reichart, Donna; McGillvray, Shauna M.; Wingender, Gerhard; Kronenberg, Mitchell; Glass, Christopher K.; Nizet, Victor; Brenner, David A.

2011-01-01

278

The Human Natural Killer Cell Immune Synapse  

NASA Astrophysics Data System (ADS)

Inhibitory killer Ig-like receptors (KIR) at the surface of natural killer (NK) cells induced clustering of HLA-C at the contacting surface of target cells. In this manner, inhibitory immune synapses were formed as human NK cells surveyed target cells. At target/NK cell synapses, HLA-C/KIR distributed into rings around central patches of intercellular adhesion molecule-1/lymphocyte function-associated antigen-1, the opposite orientation to mature murine T cell-activating synapses. This organization of protein was stable for at least 20 min. Cells could support multiple synapses simultaneously, and clusters of HLA-C moved as NK cells crawled over target cells. Clustering required a divalent metal cation, explaining how metal chelators inhibit KIR function. Surprisingly, however, formation of inhibitory synapses was unaffected by ATP depletion and the cytoskeletal inhibitors, colchicine and cytochalsins B and D. Clearly, supramolecular organization within plasma membranes is critical for NK cell immunosurveillance.

Davis, Daniel M.; Chiu, Isaac; Fassett, Marlys; Cohen, George B.; Mandelboim, Ofer; Strominger, Jack L.

1999-12-01

279

Therapeutic Immunization with HIV-1 Tat Reduces Immune Activation and Loss of Regulatory T-Cells and Improves Immune Function in Subjects on HAART  

PubMed Central

Although HAART suppresses HIV replication, it is often unable to restore immune homeostasis. Consequently, non-AIDS-defining diseases are increasingly seen in treated individuals. This is attributed to persistent virus expression in reservoirs and to cell activation. Of note, in CD4+ T cells and monocyte-macrophages of virologically-suppressed individuals, there is continued expression of multi-spliced transcripts encoding HIV regulatory proteins. Among them, Tat is essential for virus gene expression and replication, either in primary infection or for virus reactivation during HAART, when Tat is expressed, released extracellularly and exerts, on both the virus and the immune system, effects that contribute to disease maintenance. Here we report results of an ad hoc exploratory interim analysis (up to 48 weeks) on 87 virologically-suppressed HAART-treated individuals enrolled in a phase II randomized open-label multicentric clinical trial of therapeutic immunization with Tat (ISS T-002). Eighty-eight virologically-suppressed HAART-treated individuals, enrolled in a parallel prospective observational study at the same sites (ISS OBS T-002), served for intergroup comparison. Immunization with Tat was safe, induced durable immune responses, and modified the pattern of CD4+ and CD8+ cellular activation (CD38 and HLA-DR) together with reduction of biochemical activation markers and persistent increases of regulatory T cells. This was accompanied by a progressive increment of CD4+ T cells and B cells with reduction of CD8+ T cells and NK cells, which were independent from the type of antiretroviral regimen. Increase in central and effector memory and reduction in terminally-differentiated effector memory CD4+ and CD8+ T cells were accompanied by increases of CD4+ and CD8+ T cell responses against Env and recall antigens. Of note, more immune-compromised individuals experienced greater therapeutic effects. In contrast, these changes were opposite, absent or partial in the OBS population. These findings support the use of Tat immunization to intensify HAART efficacy and to restore immune homeostasis. Trial registration ClinicalTrials.gov NCT00751595 PMID:21085635

Ensoli, Barbara; Bellino, Stefania; Tripiciano, Antonella; Longo, Olimpia; Francavilla, Vittorio; Marcotullio, Simone; Cafaro, Aurelio; Picconi, Orietta; Paniccia, Giovanni; Scoglio, Arianna; Arancio, Angela; Ariola, Cristina; Ruiz Alvarez, Maria J.; Campagna, Massimo; Scaramuzzi, Donato; Iori, Cristina; Esposito, Roberto; Mussini, Cristina; Ghinelli, Florio; Sighinolfi, Laura; Palamara, Guido; Latini, Alessandra; Angarano, Gioacchino; Ladisa, Nicoletta; Soscia, Fabrizio; Mercurio, Vito S.; Lazzarin, Adriano; Tambussi, Giuseppe; Visintini, Raffaele; Mazzotta, Francesco; Di Pietro, Massimo; Galli, Massimo; Rusconi, Stefano; Carosi, Giampiero; Torti, Carlo; Di Perri, Giovanni; Bonora, Stefano; Ensoli, Fabrizio; Garaci, Enrico

2010-01-01

280

Ontogeny of murine macrophages: functions related to antigen presentation.  

PubMed Central

Macrophage function in neonates was dissected into four components: antigen uptake and catabolism, cytotoxicity, antigen presentation, and the production of the lymphostimulatory molecule interleukin-1 (also called thymocyte mitogenic protein or lymphocyte-activating factor). The uptake and catabolism of 125I-labeled Listeria monocytogenes was equivalent in macrophages from adult and neonatal mice. However, interactions between macrophages from neonates, heat-killed Listeria organisms, and immune T lymphocytes were impaired, and no cytocidal macrophages capable of killing tumor cells were generated. Previous studies with cells from adult mice had established that the development of cytocidal macrophages required Ia-bearing, antigen-presenting macrophages and histocompatibility at I-A between macrophages and T cells. To circumvent this requirement for antigen-presenting macrophages, an assay was used in which lymphokine was added directly to the macrophages from neonates. Strong cytocidal activity resulted. Thus, our studies confirmed that macrophages from neonates present antigen poorly but can acquire cytocidal function provided that the need for antigen-presenting function is bypassed. Similar conclusions were reached for the secretion of interleukin-1. Macrophages from neonates spontaneously secreted as much mediator as macrophages from adults, and the secretion was increased after the ingestion of heat-killed Listeria organisms or endotoxin. However, the marked increase in interleukin-1 production that follows antigen-macrophage-lymphocyte interaction was best seen in macrophages from adults. Macrophages from neonates could be activated to ingest C3b-coated sheep erythrocytes. PMID:6804386

Lu, C Y; Unanue, E R

1982-01-01

281

Lipid body accumulation alters calcium signaling dynamics in immune cells.  

PubMed

There is well-established variability in the numbers of lipid bodies (LB) in macrophages, eosinophils, and neutrophils. Similarly to the steatosis observed in adipocytes and hepatocytes during hyperinsulinemia and nutrient overload, immune cell LB hyper-accumulate in response to bacterial and parasitic infection and inflammatory presentations. Recently we described that hyperinsulinemia, both in vitro and in vivo, drives steatosis and phenotypic changes in primary and transformed mast cells and basophils. LB reach high numbers in these steatotic cytosols, and here we propose that they could dramatically impact the transcytoplasmic signaling pathways. We compared calcium release and influx responses at the population and single cell level in normal and steatotic model mast cells. At the population level, all aspects of Fc?RI-dependent calcium mobilization, as well as activation of calcium-dependent downstream signaling targets such as NFATC1 phosphorylation are suppressed. At the single cell level, we demonstrate that LB are both sources and sinks of calcium following Fc?RI cross-linking. Unbiased analysis of the impact of the presence of LB on the rate of trans-cytoplasmic calcium signals suggest that LB enrichment accelerates calcium propagation, which may reflect a Bernoulli effect. LB abundance thus impacts this fundamental signaling pathway and its downstream targets. PMID:25016314

Greineisen, William E; Speck, Mark; Shimoda, Lori M N; Sung, Carl; Phan, Nolwenn; Maaetoft-Udsen, Kristina; Stokes, Alexander J; Turner, Helen

2014-09-01

282

Detection of fluorescent nanoparticle interactions with primary immune cell subpopulations by flow cytometry.  

PubMed

Engineered nanoparticles are endowed with very promising properties for therapeutic and diagnostic purposes. This work describes a fast and reliable method of analysis by flow cytometry to study nanoparticle interaction with immune cells. Primary immune cells can be easily purified from human or mouse tissues by antibody-mediated magnetic isolation. In the first instance, the different cell populations running in a flow cytometer can be distinguished by the forward-scattered light (FSC), which is proportional to cell size, and the side-scattered light (SSC), related to cell internal complexity. Furthermore, fluorescently labeled antibodies against specific cell surface receptors permit the identification of several subpopulations within the same sample. Often, all these features vary when cells are boosted by external stimuli that change their physiological and morphological state. Here, 50 nm FITC-SiO2 nanoparticles are used as a model to identify the internalization of nanostructured materials in human blood immune cells. The cell fluorescence and side-scattered light increase after incubation with nanoparticles allowed us to define time and concentration dependence of nanoparticle-cell interaction. Moreover, such protocol can be extended to investigate Rhodamine-SiO2 nanoparticle interaction with primary microglia, the central nervous system resident immune cells, isolated from mutant mice that specifically express the Green Fluorescent Protein (GFP) in the monocyte/macrophage lineage. Finally, flow cytometry data related to nanoparticle internalization into the cells have been confirmed by confocal microscopy. PMID:24747480

Gamucci, Olimpia; Bertero, Alice; Malvindi, Maria Ada; Sabella, Stefania; Pompa, Pier Paolo; Mazzolai, Barbara; Bardi, Giuseppe

2014-01-01

283

Bone resorption by macrophage polykaryons of giant cell tumour of tendon sheath.  

PubMed Central

The antigenic phenotype, ultrastructure and bone resorbing ability of mononuclear and multinucleated giant cells of four giant cell tumour of tendon sheath (GCTTS) lesions was assessed. Both the giant cells and the mononuclear cells exhibited the antigenic phenotype of cells of the monocyte/macrophage lineage. The giant cells, unlike osteoclasts, did not respond morphologically to calcitonin and showed ultrastructural and immunophenotypic features of macrophage polykaryons. However, like osteoclasts, the giant cells showed direct evidence of resorption pit formation on bone slices. This indicates that the GCTTS is composed of cells of histiocytic differentiation with the giant and mononuclear cell components expressing a similar antigenic phenotype. Bone resorption by macrophage polykaryons shows that this is not a unique defining characteristic of osteoclasts. Qualitative differences in the degree and pattern of bone resorption by macrophage polykaryons distinguish it from that of osteoclasts and may underlie the clinical behaviour of osteolytic lesions. Images Figure 1 Figure 2 Figure 3 Figure 4 PMID:1850609

Athanasou, N. A.; Quinn, J.; Ferguson, D. J.; McGee, J. O.

1991-01-01

284

IL-12 suppression during experimental endotoxin tolerance: dendritic cell loss and macrophage hyporesponsiveness.  

PubMed

Endotoxin tolerance, the transient, secondary down-regulation of a subset of endotoxin-driven responses after exposure to bacterial products, is thought to be an adaptive response providing protection from pathological hyperactivation of the innate immune system during bacterial infection. However, although protecting from the development of sepsis, endotoxin tolerance also can lead to fatal blunting of immunological responses to subsequent infections in survivors of septic shock. Despite considerable experimental effort aimed at characterizing the molecular mechanisms responsible for a variety of endotoxin tolerance-related phenomena, no consensus has been achieved yet. IL-12 is a macrophage- and dendritic cell (DC)-derived cytokine that plays a key role in pathological responses to endotoxin as well as in the induction of protective responses to pathogens. It recently has been shown that IL-12 production is suppressed in endotoxin tolerance, providing a likely partial mechanism for the increased risk of secondary infections in sepsis survivors. We examined the development of IL-12 suppression during endotoxin tolerance in mice. Decreased IL-12 production in vivo is clearly multifactorial, involving both loss of CD11c(high) DCs as well as alterations in the responsiveness of macrophages and remaining splenic DCs. We find no demonstrable mechanistic role for B or T lymphocytes, the soluble mediators IL-10, TNF-alpha, IFN-alphabeta, or nitric oxide, or the NF-kappaB family members p50, p52, or RelB. PMID:11390504

Wysocka, M; Robertson, S; Riemann, H; Caamano, J; Hunter, C; Mackiewicz, A; Montaner, L J; Trinchieri, G; Karp, C L

2001-06-15

285

Mast cells in the development of adaptive immune responses  

Microsoft Academic Search

Mast cells are so widely recognized as critical effector cells in allergic disorders and other immunoglobulin E–associated acquired immune responses that it can be difficult to think of them in any other context. However, mast cells also can be important as initiators and effectors of innate immunity. In addition, mast cells that are activated during innate immune responses to pathogens,

Susumu Nakae; Mindy Tsai; Stephen J Galli

2005-01-01

286

Isolation of Immune Cells from Primary Tumors  

PubMed Central

Tumors create a unique immunosuppressive microenvironment (tumor microenvironment, TME) whereby leukocytes are recruited into the tumor by various chemokines and growth factors 1,2. However, once in the TME, these cells lose the ability to promote anti-tumor immunity and begin to support tumor growth and down-regulate anti-tumor immune responses 3-4. Studies on tumor-associated leukocytes have mainly focused on cells isolated from tumor-draining lymph nodes or spleen due to the inherent difficulties in obtaining sufficient cell numbers and purity from the primary tumor. While identifying the mechanisms of cell activation and trafficking through the lymphatic system of tumor bearing mice is important and may give insight to the kinetics of immune responses to cancer, in our experience, many leukocytes, including dendritic cells (DCs), in tumor-draining lymph nodes have a different phenotype than those that infiltrate tumors 5,6 . Furthermore, we have previously demonstrated that adoptively-transferred T cells isolated from the tumor-draining lymph nodes are not tolerized and are capable of responding to secondary stimulation in vitro unlike T cells isolated from the TME, which are tolerized and incapable of proliferation or cytokine production 7,8. Interestingly, we have shown that changing the tumor microenvironment, such as providing CD4+ T helper cells via adoptive transfer, promotes CD8+ T cells to maintain pro-inflammatory effector functions 5. The results from each of the previously mentioned studies demonstrate the importance of measuring cellular responses from TME-infiltrating immune cells as opposed to cells that remain in the periphery. To study the function of immune cells which infiltrate tumors using the Miltenyi Biotech isolation system9, we have modified and optimized this antibody-based isolation procedure to obtain highly enriched populations of antigen presenting cells and tumor antigen-specific cytotoxic T lymphocytes. The protocol includes a detailed dissection of murine prostate tissue from a spontaneous prostate tumor model (TRansgenic Adenocarcinoma of the Mouse Prostate -TRAMP) 10 and a subcutaneous melanoma (B16) tumor model followed by subsequent purification of various leukocyte populations. PMID:22733225

Watkins, Stephanie K.; Zhu, Ziqiang; Watkins, Keith E.; Hurwitz, Arthur A.

2012-01-01

287

The flavonoid fisetin attenuates postischemic immune cell infiltration, activation and infarct size after transient cerebral middle artery occlusion in mice.  

PubMed

The development of the brain tissue damage in ischemic stroke is composed of an immediate component followed by an inflammatory response with secondary tissue damage after reperfusion. Fisetin, a flavonoid, has multiple biological effects, including neuroprotective and antiinflammatory properties. We analyzed the effects of fisetin on infarct size and the inflammatory response in a mouse model of stroke, temporary middle cerebral artery occlusion, and on the activation of immune cells, murine primary and N9 microglial and Raw264.7 macrophage cells and human macrophages, in an in vitro model of inflammatory immune cell activation by lipopolysaccharide (LPS). Fisetin not only protected brain tissue against ischemic reperfusion injury when given before ischemia but also when applied 3 hours after ischemia. Fisetin also prominently inhibited the infiltration of macrophages and dendritic cells into the ischemic hemisphere and suppressed the intracerebral immune cell activation as measured by intracellular tumor necrosis factor ? (TNF?) production. Fisetin also inhibited LPS-induced TNF? production and neurotoxicity of macrophages and microglia in vitro by suppressing nuclear factor ?B activation and JNK/Jun phosphorylation. Our findings strongly suggest that the fisetin-mediated inhibition of the inflammatory response after stroke is part of the mechanism through which fisetin is neuroprotective in cerebral ischemia. PMID:22234339

Gelderblom, Mathias; Leypoldt, Frank; Lewerenz, Jan; Birkenmayer, Gabriel; Orozco, Denise; Ludewig, Peter; Thundyil, John; Arumugam, Thiruma V; Gerloff, Christian; Tolosa, Eva; Maher, Pamela; Magnus, Tim

2012-05-01

288

15-Deoxy-?(12,14)-prostaglandin J(2) attenuates the biological activities of monocyte/macrophage cell lines.  

PubMed

Monocytes/macrophages link the innate and adaptive immune systems, and in inflammatory disorders their activation leads to tissue damage. 15-Deoxy-?(12,14)-prostaglandin J(2) (15d-PGJ(2)), a natural peroxisome proliferator-activated receptor gamma (PPAR?) ligand, has garnered much interest because it possesses anti-inflammatory properties in a number of experimental models. However, whether it regulates monocytes/macrophage pathophysiology is still unknown. This study was designed to examine the effects of 15d-PGJ(2) on the phagocytosis, proliferation and inflammatory cytokines generation in mouse monocyte/macrophage cell line RAW264.7 and J774A.1 cells upon lipopolysaccharide challenge. Our results showed that 15d-PGJ(2) inhibited the phagocytic activity and cell proliferation in a dose-dependent manner, and suppressed proinflammatory cytokines expression, such as tumor necrosis factor-?, transforming growth factor-?1, interleukin-6, and monocyte chemotactic protein-1. These effects were independent of PPAR?, because PPAR? agonist (troglitazone or ciglitazone) and PPAR? antagonist (GW9662) did not affect these activities mentioned above in cells. Treatment of 15d-PGJ(2) also did not modulate expression and distribution of PPAR?. However, these effects of 15d-PGJ(2) were abrogated by antioxidant N-acetylcysteine. Moreover, treatment of 15d-PGJ(2) induced a significant increase in reactive oxygen species production in RAW264.7 and J774A.1 cells. In conclusion, 15d-PGJ(2) attenuates the biological activities of mouse monocyte/macrophage cell line cells involving oxidative stress, independently of PPAR?. These data further underline the anti-inflammation potential of 15d-PGJ(2). PMID:22560326

Liu, Xin; Yu, Hao; Yang, Lin; Li, Changyong; Li, Liying

2012-08-01

289

Innate immune response precedes Mycobacterium leprae-induced reprogramming of adult Schwann cells.  

PubMed

Recently, we showed a natural reprogramming process during infection with Mycobacterium leprae (ML), the causative organism of human leprosy. ML hijacks the notable plasticity of adult Schwann cells in the peripheral nervous system (PNS), bacteria's preferred nonimmune niche, to reprogram infected cells to progenitor/stem cell-like cells (pSLCs). Whereas ML appear to use this reprogramming process as a sophisticated bacterial strategy to spread infection to other tissues, understanding the mechanisms may shed new insights into the basic biology of cellular reprogramming and the development of new approaches for generating pSLC for therapeutic purposes as well as targeting bacterial infectious diseases at an early stage. Toward these goals, we extended our studies to identify other players that might be involved in this complex host cell reprogramming. Here we show that ML activates numerous immune-related genes mainly involved in innate immune responses and inflammation during early infection before downregulating Schwann cell lineage genes and reactivating developmental transcription factors. We validated these findings by demonstrating the ability of infected cells to secrete soluble immune factor proteins at early time points and their continued release during the course of reprogramming. By using time-lapse microscopy and a migration assay with reprogrammed Schwann cells (pSLCs) cultured with macrophages, we show that reprogrammed cells possess the ability to attract macrophages, providing evidence for a functional role of immune gene products during reprogramming. These findings suggest a potential role of innate immune response and the related signaling pathways in cellular reprogramming and the initiation of neuropathogenesis during ML infection. PMID:24279882

Masaki, Toshihiro; McGlinchey, Aidan; Cholewa-Waclaw, Justyna; Qu, Jinrong; Tomlinson, Simon R; Rambukkana, Anura

2014-02-01

290

Studying the role of macrophages in circulating prostate cancer cells by in vivo flow cytometry  

NASA Astrophysics Data System (ADS)

Metastasis is a very complicated multi-step process and accounts for the low survival rate of the cancerous patients. To metastasize, the malignant cells must detach from the primary tumor and migrate to secondary sites in the body through either blood or lymph circulation. Macrophages appear to be directly involved in tumor progression and metastasis. However, the role of macrophages in affecting cancer metastasis has not been fully elucidated. Here, we have utilized an emerging technique, namely in vivo flow cytometry (IVFC) to study the depletion kinetics of circulating prostate cancer cells in mice and how depletion of macrophages by the liposome-encapsulated clodronate affects the depletion kinetics. Our results show different depletion kinetics of PC-3 cells between macrophage-deficient group and the control group. The number of circulating tumor cells (CTCs) in macrophage-deficient group decreases in a slower manner compared to the control mice group. The differences in depletion kinetics indicate that the absence of macrophages facilitates the stay of prostate cancer cells in circulation. We speculate that macrophages might be able to arrest, phagocytose and digest PC-3 cells. Therefore, the phagocytosis may mainly contribute to the depletion kinetic differences. The developed methods here would be useful to study the relationship between macrophages and tumor metastasis in small animal cancer model.

Cui, Xiaojun; Guo, Jin; Gu, Zhengqin; Wei, Xunbin

2012-12-01

291

Mice with a selective impairment of IFN-? signaling in macrophage lineage cells demonstrate the critical role of IFN-? activated macrophages for the control of protozoan parasitic infections in vivo1, 2  

PubMed Central

IFN-? has long been recognized as a cytokine with potent and varied effects in the immune response. While its effects on specific cell types have been well studied in vitro, its in vivo effects are less clearly understood because of its diverse actions on many different cell types. While control of multiple protozoan parasites is thought to depend critically on the direct action of IFN-? on macrophages, this premise has never been directly proven in vivo. In order to more directly examine the effects of IFN-? on cells of the macrophage lineage in vivo, we generated mice called the ‘Macrophages Insensitive to Interferon Gamma’ (MIIG) mice, which express a dominant negative mutant IFN-? receptor in CD68+ cells: monocytes, macrophages, dendritic cells, and mast cells. Macrophage lineage cells and mast cells from these mice are unable to respond to IFN-? while other cells are able to produce and respond to this cytokine normally. When challenged in vitro, macrophages from MIIG mice were unable produce NO or kill Trypanosoma cruzi or Leishmania major after priming with IFN-?. Furthermore, MIIG mice demonstrated impaired parasite control and heightened mortality after T. cruzi, L. major, and Toxoplasma gondii infection, despite an appropriate IFN-? response. In contrast, MIIG mice displayed normal control of lymphocytic choriomeningitis virus, despite persistent insensitivity of macrophages to IFN-?. Thus, the MIIG mouse formally demonstrates for the first time in vivo, the specific importance of direct, IFN-? mediated activation of macrophages for controlling infection with multiple protozoan parasites. “This is an author-produced version of a manuscript accepted for publication in The Journal of Immunology (The JI). The American Association of Immunologists, Inc. (AAI), publisher of The JI, holds the copyright to this manuscript. This version of the manuscript has not yet been copyedited or subjected to editorial proofreading by The JI; hence, it may differ from the final version published in The JI (online and in print). AAI (The JI) is not liable for errors or omissions in this author-produced version of the manuscript or in any version derived from it by the U.S. National Institutes of Health or any other third party. The final, citable version of record can be found at www.jimmunol.org.” PMID:20018611

Lykens, Jennifer E.; Terrell, Catherine E.; Zoller, Erin E.; Divanovic, Senad; Trompette, Aurelien; Karp, Christopher L.; Aliberti, Julio; Flick, Matthew J.; Jordan, Michael B.

2010-01-01

292

Selenoprotein K is required for palmitoylation of CD36 in macrophages: implications in foam cell formation and atherogenesis.  

PubMed

Selk is an ER transmembrane protein important for calcium flux and macrophage activation, but its role in foam cell formation and atherosclerosis has not been evaluated. BMDMs from Selk(-/-) mice exhibited decreased uptake of modLDL and foam cell formation compared with WT controls, and the differences were eliminated with anti-CD36 blocking antibody. CD36 expression was decreased in TNF-?-stimulated Selk(-/-) BMDMs compared with WT controls. Fluorescence microscopy revealed TNF-?-induced clustering of CD36 in WT BMDMs indicative of lipid raft localization, which was absent in Selk(-/-) BMDMs. Fractionation revealed lower levels of CD36 reaching lipid rafts in TNF-?-stimulated Selk(-/-) BMDMs. Immunoprecipitation showed that Selk(-/-) BMDMs have decreased CD36 palmitoylation, which occurs at the ER membrane and is crucial for stabilizing CD36 expression and directing its localization to lipid rafts. To assess if this phenomenon had a role in atherogenesis, a HFD was fed to irradiated Ldlr(-/-) mice reconstituted with BM from Selk(-/-) or WT mice. Selk was detected in aortic plaques of controls, particularly in macrophages. Selk(-/-) in immune cells led to reduction in atherosclerotic lesion formation without affecting leukocyte migration into the arterial wall. These findings suggest that Selk is important for stable, localized expression of CD36 in macrophages during inflammation, thereby contributing to foam cell formation and atherogenesis. PMID:23444136

Meiler, Svenja; Baumer, Yvonne; Huang, Zhi; Hoffmann, Fukun W; Fredericks, Gregory J; Rose, Aaron H; Norton, Robert L; Hoffmann, Peter R; Boisvert, William A

2013-05-01

293

DEVELOPMENT OF A NOVEL, CELL-BASED CHEMICAL SCREEN TO IDENTIFY INHIBITORS OF INTRAPHAGOSOMAL LIPOLYSIS IN MACROPHAGES  

PubMed Central

Macrophages play a central role in tissue homeostasis and the immune system. Their primary function is to internalize cellular debris and microorganisms for degradation within their phagosomes. In this context, their capacity to process and sequester lipids such as triacylglycerides and cholesteryl esters makes them key players in circulatory diseases such as atheroclerosis. To discover new inhibitors of lipolytic processing within the phagosomal system of the macrophage we have developed a novel, cell-based assay suitable for high-throughput screening. We employed particles carrying a fluorogenic triglyceride substrate and a calibration fluor to screen for inhibitors of phagosomal lipolysis. A panel of secondary assays were employed to discriminate between lipase inhibitors and compounds that perturbed general phagosomal trafficking events. This process enabled us to identify a new structural class of pyrazole-methanone compounds that directly inhibit lysosomal and lipoprotein lipase activity. PMID:20653015

VanderVen, Brian C.; Hermetter, Albin; Huang, Amy; Maxfield, Fredrick R; Russell, David G; Yates, Robin M.

2010-01-01

294

Prenatal cadmium exposure alters postnatal immune cell development and function  

PubMed Central

Cadmium (Cd) is generally found in low concentrations in the environment due to its widespread and continual use, however, its concentration in some foods and cigarette smoke is high. Although evidence demonstrates that adult exposure to Cd causes changes in the immune system, there are limited reports of immunomodulatory effects of prenatal exposure to Cd. This study was designed to investigate the effects of prenatal exposure to Cd on the immune system of the offspring. Pregnant C57Bl/6 mice were exposed to an environmentally relevant dose of CdCl2 (10 ppm) and the effects on the immune system of the offspring were assessed at two time points following birth (2 and 7 weeks of age). Thymocyte and splenocyte phenotypes were analyzed by flow cytometry. Prenatal Cd exposure did not affect thymocyte populations at 2 and 7 weeks of age. In the spleen, the only significant effect on phenotype was a decrease in the number of macrophages in male offspring at both time points. Analysis of cytokine production by stimulated splenocytes demonstrated that prenatal Cd exposure decreased IL-2 and IL-4 production by cells from female offspring at 2 weeks of age. At 7 weeks of age, splenocyte IL-2 production was decreased in Cd-exposed males while IFN-? production was decreased from both male and female Cd-exposed offspring. The ability of the Cd-exposed offspring to respond to immunization with a S. pneumoniae vaccine expressing T-dependent and T-independent streptococcal antigens showed marked increases in the levels of both T-dependent and T-independent serum antibody levels compared to control animals. CD4+FoxP3+CD25+ (nTreg) cell percentages were increased in the spleen and thymus in all Cd-exposed offspring except in the female spleen where a decrease was seen. CD8+CD223+ T cells were markedly decreased in the spleens in all offspring at 7 weeks of age. These findings suggest that even very low levels of Cd exposure during gestation can result in long term detrimental effects on the immune system of the offspring and these effects are to some extent sex-specific. PMID:22521604

Hanson, Miranda L.; Holaskova, Ida; Elliott, Meenal; Brundage, Kathleen M.; Schafer, Rosana; Barnett, John B.

2012-01-01

295

Molecular Pathways: Tumor-derived microvesicles and their interactions with immune cells in vivo  

PubMed Central

Cancer is not merely a cell-intrinsic genetic disease, but also the result of complex cell-extrinsic interactions with host components, including immune cells. For example, effector T lymphocytes and NK cells are thought to participate in an immunosurveillance process which eliminates neoplastic cells, whereas regulatory T lymphocytes and some myeloid cells, including macrophages, can create a milieu that prevents anti-tumor activity, supports tumor growth and reduces survival of the host. Increasing evidence supports the notion that carcinoma cells communicate with immune cells directly, both within and away from the tumor stroma, and that this process fosters suppression of immunosurveillance and promotes tumor outgrowth. An important mode of communication between carcinoma cells and immune cells may involve tumor-derived microvesicles (tMVs), also known as exosomes, ectosomes, or microparticles. These microvesicles carry lipids, proteins, mRNAs and miRNAs, and travel short or long distances to deliver undegraded and undiluted material to other cells. Here we consider the capacity of tMVs to control tumor-associated immune responses, and highlight the known and unknown tMV’s actions in vivo. We also discuss why microvesicles may play a role in cancer diagnostics and prognostics, and how they could be harnessed for anti-cancer therapy. PMID:23426276

Pucci, Ferdinando; Pittet, Mikael J

2013-01-01

296

Innate Immune Responses to Lung-Stage Helminth Infection Induce Alternatively Activated Alveolar Macrophages  

Microsoft Academic Search

While it is well established that infection with the rodent hookworm Nippostrongylus brasiliensis induces a strongly polarized Th2 immune response, little is known about the innate host-parasite interactions that lead to the development of this robust Th2 immunity. We exploited the transient pulmonary phase of N. brasiliensis development to study the innate immune responses induced by this helminth parasite in

Joshua J. Reece; Mark C. Siracusa; Alan L. Scott

2006-01-01

297

Macrophages Discriminate Glycosylation Patterns of Apoptotic Cell-derived Microparticles*  

PubMed Central

Inappropriate clearance of apoptotic remnants is considered to be the primary cause of systemic autoimmune diseases, like systemic lupus erythematosus. Here we demonstrate that apoptotic cells release distinct types of subcellular membranous particles (scMP) derived from the endoplasmic reticulum (ER) or the plasma membrane. Both types of scMP exhibit desialylated glycotopes resulting from surface exposure of immature ER-derived glycoproteins or from surface-borne sialidase activity, respectively. Sialidase activity is activated by caspase-dependent mechanisms during apoptosis. Cleavage of sialidase Neu1 by caspase 3 was shown to be directly involved in apoptosis-related increase of surface sialidase activity. ER-derived blebs possess immature mannosidic glycoepitopes and are prioritized by macrophages during clearance. Plasma membrane-derived blebs contain nuclear chromatin (DNA and histones) but not components of the nuclear envelope. Existence of two immunologically distinct types of apoptotic blebs may provide new insights into clearance-related diseases. PMID:22074924

Bilyy, Rostyslav O.; Shkandina, Tanya; Tomin, Andriy; Muñoz, Luis E.; Franz, Sandra; Antonyuk, Volodymyr; Kit, Yuriy Ya.; Zirngibl, Matthias; Fürnrohr, Barbara G.; Janko, Christina; Lauber, Kirsten; Schiller, Martin; Schett, Georg; Stoika, Rostyslav S.; Herrmann, Martin

2012-01-01

298

Activation of peritoneal macrophages to cytoxicity against B16 melanoma cells by Serratia marcescens polyribosome fractions  

SciTech Connect

Serratia marcescens polyribosomes (SMPR) have been shown to elicit an anti-tumor response in vivo. The in-vitro effects of SMPR on macrophages as the nonspecific mediators of the anti-tumor response have not previously been examined. The first objective of this research project is to corroborate and analyze the in-vivo results by the development and application of an in-vitro cytotoxicity assay. The second objective is to examine the effect of SMPR upon previously unstimulated peritoneal macrophages as representing the mechanism of cytotoxicity. The third objective is to identify the minimal effective component of SMPR responsible for an effect on macrophages. Results revealed that SMPR preparations exert a number of effects upon macrophages. Morphologic changes included increased spreading and increased perinuclear vacuolization. Macrophages were shown to be metabolically activate by two lines of evidence. SMPR-treated macrophages exhibited increased cellular metabolism by the increased uptake of /sup 3/H-thymidine and by the increased levels of secreted leucine aminopeptidase as compared to control macrophages. Results also showed that SMPR activates macrophages to cytotoxicity against syngeneic tumor target cells. Buoyant-density fractions were isolated and assayed for macrophage activating ability. Results showed 50S ribosomal subunits to be the smallest fraction effective for macrophage activation. Both the RNA and protein were necessary for complete effectiveness.

Hoover, S.K.

1985-01-01

299

No evidence of altered alveolar macrophage polarization, but reduced expression of TLR2, in bronchoalveolar lavage cells in sarcoidosis  

PubMed Central

Background Sarcoidosis is a granulomatous inflammatory disease, possibly of infectious aetiology. We aimed to investigate whether the degree of functional polarization of alveolar macrophages (AMs), or Toll-like receptor (TLR) expression, is associated with sarcoidosis or with distinct clinical manifestations of this disease. Methods Total BAL cells (cultured four or 24 h in medium, or stimulated 24 h with LPS) from 14 patients and six healthy subjects, sorted AMs from 22 patients (Löfgren's syndrome n = 11) and 11 healthy subjects, and sorted CD4+ T cells from 26 patients (Löfgren's syndrome n = 13) and seven healthy subjects, were included. Using real-time PCR, the relative gene expression of IL-10, IL-12p35, IL-12p40, IL-23p19, CCR2, CCR7, iNOS, CXCL10, CXCL11, CXCL16, CCL18, CCL20, CD80, and CD86, and innate immune receptors TLR2, TLR4, and TLR9, was quantified in sorted AMs, and for selected genes in total BAL cells, while IL-17A was quantified in T cells. Results We did not find evidence of a difference with regard to alveolar macrophage M1/M2 polarization between sarcoidosis patients and healthy controls. TLR2 gene expression was significantly lower in sorted AMs from patients, particular in Löfgren's patients. CCL18 gene expression in AMs was significantly higher in patients compared to controls. Additionally, the IL-17A expression was lower in Löfgren's patients' CD4+ T cells. Conclusions Overall, there was no evidence for alveolar macrophage polarization in sarcoidosis. However, there was a reduced TLR2 mRNA expression in patients with Löfgren's syndrome, which may be of relevance for macrophage interactions with a postulated sarcoidosis pathogen, and for the characteristics of the ensuing T cell response. PMID:20813038

2010-01-01

300

Tumor-altered dendritic cell function: implications for anti-tumor immunity.  

PubMed

Dendritic cells (DC) are key regulators of both innate and adaptive immunity, and the array of immunoregulatory functions exhibited by these cells is dictated by their differentiation, maturation, and activation status. Although a major role for these cells in the induction of immunity to pathogens has long been appreciated, data accumulated over the last several years has demonstrated that DC are also critical regulators of anti-tumor immune responses. However, despite the potential for stimulation of robust anti-tumor immunity by DC, tumor-altered DC function has been observed in many cancer patients and tumor-bearing animals and is often associated with tumor immune escape. Such dysfunction has significant implications for both the induction of natural anti-tumor immune responses as well as the efficacy of immunotherapeutic strategies that target endogenous DC in situ or that employ exogenous DC as part of anti-cancer immunization maneuvers. In this review, the major types of tumor-altered DC function will be described, with emphasis on recent insights into the mechanistic bases for the inhibition of DC differentiation from hematopoietic precursors, the altered programing of DC precursors to differentiate into myeloid-derived suppressor cells or tumor-associated macrophages, the suppression of DC maturation and activation, and the induction of immunoregulatory DC by tumors, tumor-derived factors, and tumor-associated cells within the milieu of the tumor microenvironment. The impact of these tumor-altered cells on the quality of the overall anti-tumor immune response will also be discussed. Finally, this review will also highlight questions concerning tumor-altered DC function that remain unanswered, and it will address factors that have limited advances in the study of this phenomenon in order to focus future research efforts in the field on identifying strategies for interfering with tumor-associated DC dysfunction and improving DC-mediated anti-tumor immunity. PMID:23874338

Hargadon, Kristian M

2013-01-01

301

TLR9 and RIG-I Signaling in Human Endocervical Epithelial Cells Modulates Inflammatory Responses of Macrophages and Dendritic Cells In Vitro  

PubMed Central

The innate immune system has evolved to recognize invading pathogens through pattern recognition receptors (PRRs).Among PRRs, Toll like receptors (TLRs 3, 7/8,9) and RIG-I like receptors (RLRs) have been shown to recognize viral components. Mucosal immune responses to viral infections require coordinated actions from epithelial as well as immune cells. In this respect, endocervical epithelial cells (EEC's) play an important role in initiating innate immune responses via PRRs. It is unknown whether EEC's can alter immune responses of macrophages and dendritic cells (DC's) like its counterparts in intestinal and respiratory systems. In this study, we show that endocervical epithelial cells (End1/E6E7) express two key receptors, TLR9 and RIG-I involved in anti-viral immunity. Stimulation of End1/E6E7 cells lead to the activation of NF-?B and increased secretion of pro-inflammatory cytokines, IL-6 and IL-8. Polarized End1/E6E7 cells responded to apical stimulation with ligands of TLR9 and RIG-I, CpG-ODN and Poly(I:C)LL respectively, without compromising End1/E6E7 cell integrity. At steady state, spent medium from End1/E6E7 cells significantly reduced secretion of pro-inflammatory cytokines from LPS treated human primary monocyte derived macrophages (MDMs) and DC:T cell co-cultures. Spent medium from End1/E6E7 cells stimulated with ligands of TLR9/RIG-I restored secretion of pro-inflammatory cytokines as well as enhanced phagocytosis and chemotaxis of monocytic U937 cells. Spent medium from CpG-ODN and Poly(I:C)LL stimulated End1/E6E7 cells showed significant increased secretion of IL-12p70 from DC:T cell co-cultures. The anti-inflammatory effect of spent media of End1/E6E7 cell was observed to be TGF-? dependent. In summary, the results of our study indicate that EEC's play an indispensable role in modulating anti-viral immune responses at the female lower genital tract. PMID:24409285

Sathe, Ameya; Reddy, Kudumula Venkata Rami

2014-01-01

302

cytotoxic T cells kill infected cells directly by inducing them to undergo apoptosis helper T cells help activate B cells, macrophages and cytotoxic T cells.  

E-print Network

cytotoxic T cells kill infected cells directly by inducing them to undergo apoptosis helper T cells help activate B cells, macrophages and cytotoxic T cells. Both classes of T cells express cell-surface, antibodylike receptors, encoded by genes that are assembled from multiple gene segments during T cell

Morante, Silvia

303

Indoleamine 2,3-dioxygenase-1 (IDO1) in human endometrial stromal cells induces macrophage tolerance through interleukin-33 in the progression of endometriosis  

PubMed Central

In the peritoneal fluid, macrophages and their secretory cytokines are essential for endometriosis, but the factors that favor their involvement in the endometriosis-associated inflammatory response are still elusive. Given the anomalous expression of indoleamine 2,3-dioxygenase-1 (IDO1) in endometrial stromal cells (ESCs) and its potentially important roles in immune modulation, we aimed to determine the effects of IDO1 in ESCs on macrophages and the mechanism of those effects. Normal ESCs and ectopic ESCs transfected with the SD11-IDO1 shRNA (short hairpin RNA) or vector-only plasmid SD11 were subsequently co-cultured with peripheral blood (PB)-derived monocytes (PBMC)-driven macrophages directly and indirectly. Cytokine production was determined by analyzing the supernatant of the co-culture unit by enzyme-linked immunosorbent assay (ELISA). The phenotypes and the phagocytic ability of the macrophages were determined by flow cytometry. Compared to normal ESCs, the PBMC-driven macrophages co-cultured with ectopic ESCs displayed lower phagocytic ability. Additionally, macrophages co-cultured with ectopic ESCs exhibited higher levels of CD163 and CD209 and lower levels of HLA-DR and CD11c. Moreover, both the intracellular expression and extracellular secretion of interleukin-10 (IL-10) and transforming growth factor-?1 (TGF-?1) were significantly increased, while that of IL-12p70 was decreased in macrophages after being co-cultured with ectopic ESCs. However, there was no significant difference in macrophage phagocytic ability, immunophenotype or cytokine secretion between the direct and indirect co-culture units. Reversely, SD11-IDO1 shRNA transfection of ectopic ESCs could abrogate the decreased phagocytic ability and alternative activation of macrophages in ectopic ESC-macrophage co-culture unit, suggesting that higher IDO1 in ectopic ESCs was indispensable for the induction of macrophage tolerance. Furthermore, the decrease in phagocytic macrophages and alternatively activated macrophages induced by IDO1 in ectopic ESCs was reversed by the addition of an IL-33 inhibitor, that is, soluble ST2 (sST2). Therefore, through the activation of IL-33, the increased expression of IDO1 in ectopic ESCs contributed to the truncated phagocytic ability of macrophages in endometriosis. PMID:25031694

Mei, Jie; Xie, Xue-Xin; Li, Ming-Qing; Wei, Chun-Yan; Jin, Li-Ping; Li, Da-Jin; Zhu, Xiao-Yong

2014-01-01

304

Imaging macrophages with nanoparticles  

NASA Astrophysics Data System (ADS)

Nanomaterials have much to offer, not only in deciphering innate immune cell biology and tracking cells, but also in advancing personalized clinical care by providing diagnostic and prognostic information, quantifying treatment efficacy and designing better therapeutics. This Review presents different types of nanomaterial, their biological properties and their applications for imaging macrophages in human diseases, including cancer, atherosclerosis, myocardial infarction, aortic aneurysm, diabetes and other conditions. We anticipate that future needs will include the development of nanomaterials that are specific for immune cell subsets and can be used as imaging surrogates for nanotherapeutics. New in vivo imaging clinical tools for noninvasive macrophage quantification are thus ultimately expected to become relevant to predicting patients' clinical outcome, defining treatment options and monitoring responses to therapy.

Weissleder, Ralph; Nahrendorf, Matthias; Pittet, Mikael J.

2014-02-01

305

A phylogenetic comparison between acute monocytic leukemia cells and monocytes-macrophages in lower vertebrates.  

PubMed

In humans, monocytes and macrophages (Mphi) play a central role in immune regulation, tissue maintenance and pathogen control. In lower vertebrates, a few studies have been conducted on Mphi like cells. In acute monocytic leukemia monocytic cells, as immature cells restrained in one of the phases of their ontogenesis, would offer the opportunity to rebuild an archaic condition helpful to understand the phylogenesis. Therefore, aim of this work was to characterize in the Rainbow trout (Salmo Gairdneri Richardson) Mphi and compare them with acute leukemia monocytic cells. In the trout, Mphi's morphology is similar to that of mammals. In particular, Mphi possess an irregular embryoshaped nucleus occupying 2/3 of the cell, while the peripheral cytoplasmic profile is irregular with extroflexed plasmalemma and pseudopods. A morphological transition towards Mphi is featured by a wavy hyaline classical membrane and an irregular and extroflexed surface. Some aspects of erythrophagocytosis represented a finding of great interest indicating that the hemocatheretic function could take place directly in circulation. This condition, also observed in human acute monocytic leukemia, suggests that the information to the erythrophagocytosis is restrained under physiological conditions. Non-specific esterases, which are positive in human Mphi smear and Mphi from human lymph node tissue, were also positive in the teleost studied but with a dysomogeneous pattern. Consequently non-specific esterase system is phylogenetically conserved. A lack of immune-reactivity with the anti-CD68 monoclonal antibody (MoAb) on smear and trout tissue sections was observed. On the contrary, strong positivity was detected on human lymph node sections. In trout, the presence of Mphi and circulating Mphi like cells exhibiting an erythrocatheretic function in the circulation would indicate a primordial function that has later been replaced by the liver and the spleen. PMID:12675202

Passantino, L; Patruno, R; Cianciotta, A; Passantino, G; Tafaro, A; Gadaleta, C; Ranieri, G

2003-02-01

306

Lassa and Mopeia virus replication in human monocytes/macrophages and in endothelial cells: different effects on IL-8 and TNF-alpha gene expression.  

PubMed

Cells of the mononuclear and endothelial lineages are targets for viruses which cause hemorrhagic fevers (HF) such as the filoviruses Marburg and Ebola, and the arenaviruses Lassa and Junin. A recent model of Marburg HF pathogenesis proposes that virus directly causes endothelial cell damage and macrophage release of TNF-alpha which increases the permeability of endothelial monolayers [Feldmann et al. , 1996]. We show that Lassa virus replicates in human monocytes/macrophages and endothelial cells without damaging them. Human endothelial cells (HUVEC) are highly susceptible to infection by both Lassa and Mopeia (a non-pathogenic Lassa-related arenavirus). Whereas monocytes must differentiate into macrophages before supporting even low level production of these viruses, the virus yields in the culture medium of infected HUVEC cells reach more than 7 log10 PFU/ml without cellular damage. In contrast to filovirus, Lassa virus replication in monocytes/macrophages fails to stimulate TNF-alpha gene expression and even down-regulates LPS-stimulated TNF-alpha mRNA synthesis. The expression of IL-8, a prototypic proinflammatory CXC chemokine, was also suppressed in Lassa virus infected monocytes/macrophages and HUVEC on both the protein and mRNA levels. This contrasts with Mopeia virus infection of HUVEC in which neither IL-8 mRNA nor protein are reduced. The cumulative down-regulation of TNF-alpha and IL-8 expression could explain the absence of inflammatory and effective immune responses in severe cases of Lassa HF. PMID:10534741

Lukashevich, I S; Maryankova, R; Vladyko, A S; Nashkevich, N; Koleda, S; Djavani, M; Horejsh, D; Voitenok, N N; Salvato, M S

1999-12-01

307

Characteristics of Suppressor Macrophages Induced by Mycobacterial and Protozoal Infections in relation to Alternatively Activated M2 Macrophages  

PubMed Central

In the advanced stages of mycobacterial infections, host immune systems tend to change from a Th1-type to Th2-type immune response, resulting in the abrogation of Th1 cell- and macrophage-mediated antimicrobial host protective immunity. Notably, this type of immune conversion is occasionally associated with the generation of certain types of suppressor macrophage populations. During the course of Mycobacterium tuberculosis (MTB) and Mycobacterium avium-intracellulare complex (MAC) infections, the generation of macrophages which possess strong suppressor activity against host T- and B-cell functions is frequently encountered. This paper describes the immunological properties of M1- and M2-type macrophages generated in tumor-bearing animals and those generated in hosts with certain microbial infections. In addition, this paper highlights the immunological and molecular biological characteristics of suppressor macrophages generated in hosts with mycobacterial infections, especially MAC infection. PMID:22666284

Tomioka, Haruaki; Tatano, Yutaka; Maw, Win Win; Sano, Chiaki; Kanehiro, Yuichi; Shimizu, Toshiaki

2012-01-01

308

Ascitic growth of a T cell lymphoma in mice alters the humoral and cellular immune response to exogenous antigens.  

PubMed

The effect of the ascitic growth of Dalton's lymphoma (DL), a T cell lymphoma, on the immune responses of the host mice to exogenous antigens, with respect to the humoral response, delayed-type hypersensitivity (DTH) response and the antigen-presenting ability of macrophages was investigated. The humoral immune response to sheep red blood cells (SRBC) as well as the antigen-presenting ability of macrophages (with keyhole limpet hemocyanin as the standard antigen) in the DL-bearing mice were consistently higher than in the normal mice, although the magnitude showed a decline during later tumor stages. However, the DTH response to SRBC was suppressed in the DL-bearing mice compared with the response in the normal mice. The possible mechanisms are discussed. In vivo administration of FK565, a synthetic biological response modifier, enhanced the humoral immune response as well as the antigen-presenting ability of the macrophages in the normal and early DL-bearing mice, whereas these immune responses n the later tumor-bearing animals were found to be nonresponsive to FK565 treatment. In contrast, the DTH response in the normal as well as in the DL-bearing mice was suppressed on FK565 administration. This is the first study of its kind regarding the effect of the ascitic growth of any T cell lymphoma on various aspects of the immune response to exogenous antigens and the correlation thereof with an immunomodulator. PMID:9222308

Parajuli, P; Singh, S M

1997-01-01

309

Comprehensive proteomic data sets for studying adipocyte-macrophage cell-cell communication.  

PubMed

Cellular communication is a fundamental process in biology. The interaction of adipocytes with macrophages is a key event in the development of common diseases such as type 2 diabetes. We applied an established bilayer cell co-culture system and comprehensive mass spectrometry analysis to detect proteome-wide the paracrine interaction of murine adipocytes and macrophages. Altogether, we identified 4486 proteins with at least two unique peptides of which 2392 proteins were informative for 3T3-L1 adipocytes and 2957 proteins for RAW 264.7 macrophages. Further, we observed over 12,000 phosphorylation sites of which we could assign 3,200 informative phosphopeptides with a single phosphosite for adipocytes and 4,514 for macrophages. Using protein set enrichment and phosphosite analyses, we deciphered regulatory protein pathways involved in cellular stress and inflammation, which can contribute to metabolic impairment of cells including insulin resistance and other disorders. The generated data sets provide a holistic, molecular pathway-centric view on the interplay of adipocytes and macrophages in disease processes and a resource for further studies. PMID:24174276

Freiwald, Anja; Weidner, Christopher; Witzke, Annabell; Huang, Sheng-Yu; Meierhofer, David; Sauer, Sascha

2013-12-01

310

Proinflammatory Caspase-2-Mediated Macrophage Cell Death Induced by a Rough Attenuated Brucella suis Strain ? †  

PubMed Central

Brucella spp. are intracellular bacteria that cause an infectious disease called brucellosis in humans and many domestic and wildlife animals. B. suis primarily infects pigs and is pathogenic to humans. The macrophage-Brucella interaction is critical for the establishment of a chronic Brucella infection. Our studies showed that smooth virulent B. suis strain 1330 (S1330) prevented programmed cell death of infected macrophages and rough attenuated B. suis strain VTRS1 (a vaccine candidate) induced strong macrophage cell death. To further investigate the mechanism of VTRS1-induced macrophage cell death, microarrays were used to analyze temporal transcriptional responses of murine macrophage-like J774.A1 cells infected with S1330 or VTRS1. In total 17,685 probe sets were significantly regulated based on the effects of strain, time and their interactions. A miniTUBA dynamic Bayesian network analysis predicted that VTRS1-induced macrophage cell death was mediated by a proinflammatory gene (the tumor necrosis factor alpha [TNF-?] gene), an NF-?B pathway gene (the I?B-? gene), the caspase-2 gene, and several other genes. VTRS1 induced significantly higher levels of transcription of 40 proinflammatory genes than S1330. A Mann-Whitney U test confirmed the proinflammatory response in VTRS1-infected macrophages. Increased production of TNF-? and interleukin 1? (IL-1?) were also detected in the supernatants in VTRS1-infected macrophage cell culture. Hyperphosphorylation of I?B-? was observed in macrophages infected with VTRS1 but not S1330. The important roles of TNF-? and I?B-? in VTRS1-induced macrophage cell death were further confirmed by individual inhibition studies. VTRS1-induced macrophage cell death was significantly inhibited by a caspase-2 inhibitor but not a caspase-1 inhibitor. The role of caspase-2 in regulating the programmed cell death of VTRS1-infected macrophages was confirmed in another study using caspase-2-knockout mice. In summary, VTRS1 induces a proinflammatory, caspase-2- and NF-?B-mediated macrophage cell death. This unique cell death differs from apoptosis, which is not proinflammatory. It is also different from classical pyroptosis, which is caspase-1 mediated. PMID:21464087

Chen, Fang; Ding, Xicheng; Ding, Ying; Xiang, Zuoshuang; Li, Xinna; Ghosh, Debashis; Schurig, Gerhardt G.; Sriranganathan, Nammalwar; Boyle, Stephen M.; He, Yongqun

2011-01-01

311

IRF3 polymorphisms induce different innate anti-Theiler's virus immune responses in RAW264.7 macrophages  

SciTech Connect

Persistent viral infections can lead to disease such as myocarditis. Theiler's murine encephalomyelitis virus (TMEV) infects macrophages of SJL/J (H-2s) mice establishing persistent infections leading to demyelinating disease. In contrast macrophages from B10.S (H-2s) mice clear TMEV. Activation of the transcription factor IRF3 induces IFN{beta}, ISG56, and apoptosis for viral clearance, but also inflammatory cytokines, such as IL-23 and IL6, which contribute to disease. Here we identify polymorphisms in the IRF3 of SJL/J versus B10.S mice that are located in DNA binding, nuclear localization, and autoinhibitory domains. SJL-IRF3 expression in RAW264.7 macrophage cells with or without TMEV infection decreased IL-23p19 promoter activity compared with B10S-IRF3. In contrast SJL-IRF3 increased IL-6, ISG56 and IFN{beta} in response to TMEV. B10S-IRF3 expression augmented apoptotic caspase activation and decreased viral RNA in TMEV-infected macrophages while SJL-IRF3 increased viral replication with less caspase activation. Therefore IRF3 polymorphisms contribute to viral persistence and altered cytokine expression.

Moore, Tyler C. [School of Biological Sciences, University of Nebraska Lincoln (United States); Al-Salleeh, Fahd M. [Endodontics, University of Nebraska Medical Center (United States); Brown, Deborah M. [School of Biological Sciences, University of Nebraska Lincoln (United States); Nebraska Center for Virology, University of Nebraska Lincoln (United States); Petro, Thomas M., E-mail: tpetro@unmc.edu [Nebraska Center for Virology, University of Nebraska Lincoln (United States); Departments of Oral Biology, University of Nebraska Medical Center (United States)

2011-09-15

312

Human decidual macrophages and NK cells differentially express Toll-like receptors and display distinct cytokine profiles upon TLR stimulation  

PubMed Central

Maternofetal pathogen transmission is partially controlled at the level of the maternal uterine mucosa at the fetal implantation site (the decidua basalis), where maternal and fetal cells are in close contact. Toll-like receptors (TLRs) may play an important role in initiating rapid immune responses against pathogens in the decidua basalis, however the tolerant microenvironment should be preserved in order to allow fetal development. Here we investigated the expression and functionality of TLRs expressed by decidual macrophages (dMs) and NK cells (dNKs), the major decidual immune cell populations. We report for the first time that both human dMs and dNK cells express mRNAs encoding TLRs 1-9, albeit with a higher expression level in dMs. TLR2, TLR3, and TLR4 protein expression checked by flow cytometry was positive for both dMs and dNK cells. In vitro treatment of primary dMs and dNK cells with specific TLR2, TLR3, TLR4, TLR7/8, and TLR9 agonists enhanced their secretion of pro- and anti-inflammatory cytokines, as well as cytokines and chemokines involved in immune cell crosstalk. Only dNK cells released IFN-?, whereas only dMs released IL-1?, IL-10, and IL-12. TLR9 activation of dMs resulted in a distinct pattern of cytokine expression compared to the other TLRs. The cytokine profiles expressed by dMs and dNK cells upon TLR activation are compatible with maintenance of the fetotolerant immune environment during initiation of immune responses to pathogens at the maternofetal interface. PMID:25071732

Duriez, Marion; Quillay, Heloise; Madec, Yoann; El Costa, Hicham; Cannou, Claude; Marlin, Romain; de Truchis, Claire; Rahmati, Mona; Barre-Sinoussi, Francoise; Nugeyre, Marie-Therese; Menu, Elisabeth

2014-01-01

313

An Essential Regulatory Role for Macrophage Migration Inhibitory Factor in T-Cell Activation  

Microsoft Academic Search

The protein known as macrophage migration inhibitory factor (MIF) was one of the first cytokines to be discovered and was described 30 years ago to be a T-cell-derived factor that inhibited the random migration of macrophages in vitro. A much broader role for MIF has emerged recently as a result of studies that have demonstrated it to be released from

Michael Bacher; Christine N. Metz; Thierry Calandra; Katrin Mayer; Jason Chesney; Michael Lohoff; Diethard Gemsa; Thomas Donnelly; Richard Bucala

1996-01-01

314

Macrophage migration inhibitory factor promotes cell death and aggravates neurologic deficits after experimental stroke  

Microsoft Academic Search

Multiple mechanisms contribute to tissue demise and functional recovery after stroke. We studied the involvement of macrophage migration inhibitory factor (MIF) in cell death and development of neurologic deficits after experimental stroke. Macrophage migration inhibitory factor is upregulated in the brain after cerebral ischemia, and disruption of the Mif gene in mice leads to a smaller infarct volume and better

Ana R Inácio; Karsten Ruscher; Lin Leng; Richard Bucala; Tomas Deierborg

2011-01-01

315

Tumor-associated macrophages induce lymphangiogenesis in cervical cancer via interaction with tumor cells.  

PubMed

Our studies were conducted to investigate the clinical and functional significance of tumor-associated macrophages (TAMs) in cervical tumor lymphatic metastasis. We found that the increase in macrophages in tumor stroma is significantly associated with lymphatic metastasis (p = 0.017), through performing immunohistochemical staining in 111 cervical samples (55 invasive squamous carcinomas of uterine cervix, 27 cervical intraepithelial neoplasms III, and 29 normal cervix). The human lymphatic endothelial cells (HLEC), which were cultured in conditioned medium of cervical cancer cell-macrophage coculture, formed more tube-like structures in vitro, when compared with those in conditioned mediums of LEC, normal cervical epithelium, single macrophage, and single cervical cancer cell (all p < 0.001). The mRNA expressions of IL-1? and IL-8 in cervical cancer cells cocultured with macrophages were increased, compared with those in cervical cancer cell cultured alone (pIL-1?  < 0.05 and pIL-8  < 0.01). Meanwhile, the mRNA expression of VEGF-C and VEGF-A was increased in macrophages cocultured with cervical cancer cells, compared with the expression in those macrophages cultured alone (both p < 0.05). Taken together, the results suggest that TAMs promote lymphangiogenesis mainly through interaction with surrounding cervical cancer cells. PMID:24698523

Ding, Hui; Cai, Jing; Mao, Min; Fang, Yan; Huang, Zaiju; Jia, Jinghui; Li, Tao; Xu, Linjuan; Wang, Junjie; Zhou, Jun; Yang, Qiang; Wang, Zehua

2014-11-01

316

Expression analysis of G Protein-Coupled Receptors in mouse macrophages  

Microsoft Academic Search

BACKGROUND: Monocytes and macrophages express an extensive repertoire of G Protein-Coupled Receptors (GPCRs) that regulate inflammation and immunity. In this study we performed a systematic micro-array analysis of GPCR expression in primary mouse macrophages to identify family members that are either enriched in macrophages compared to a panel of other cell types, or are regulated by an inflammatory stimulus, the

Jane E Lattin; Kate Schroder; Andrew I Su; John R Walker; Jie Zhang; Tim Wiltshire; Kaoru Saijo; Christopher K Glass; David A Hume; Stuart Kellie; Matthew J Sweet

2008-01-01

317

The role of macrophage migration inhibitory factor in the inflammatory immune response and rheumatoid arthritis  

Microsoft Academic Search

Summary  Rheumatoid arthritis (RA) is a debilitating disease of unknown etiology. Although the pathogenesis of RA is multifactorial, the contribution of cytokines is undoubtedly pivotal in the progression of the inflammatory process. One cytokine gaining recognition for its importance in inflammation is macrophage migration inhibitory factor (MIF). Initially described as a biological activity, a broad range of functions of MIF has

Leilani L. Santos; Eric F. Morand

2006-01-01

318

Macrophage cell lines derived from major histocompatibility complex II-negative mice  

NASA Technical Reports Server (NTRS)

Two bone-marrow-derived macrophage cell lines, C2D and C2Dt, were isolated from major histocompatibility class II negative knock-out mice. The C2D cell line was stabilized by continuous culture in colony-stimulating factor-1 and the C2Dt cell line was transformed with SV40 virus large T antigen. These cells exhibited phenotypic properties of macrophages including morphology and expression of Mac 1 and Mac 2 cell surface molecules. These cells also had comparable growth to the bone-marrow-derived macrophage cell line B6MP102. These new cell lines were not spontaneously cytotoxic and were only capable of modest killing of F5b tumor cells when stimulated with LPS and interferon-gamma, but not when stimulated with LPS alone or with staphylococcal exotoxin. C2D and C2Dt cells phagocytosed labeled Staphylococcus aureus similarly to B6MP102 cells but less well than C2D peritoneal macrophages. These cell lines secreted interleukin-6, but not tumor necrosis factor or nitric oxide in response to LPS or staphlococcal enterotoxins A or B C2D(t) cells were tumorigenic in C2D and C57BL/6J mice but C2D cells were not. These data suggest that macrophage cell lines can be established from bone marrow cells of major histocompatibility complex II-negative mice.

Beharka, A. A.; Armstrong, J. W.; Chapes, S. K.; Spooner, B. S. (Principal Investigator)

1998-01-01

319

Expression of intercellular adhesion molecule-1 on transitional cell cancer. Possible significance in immunity against tumor cells.  

PubMed Central

Immunohistochemical examination demonstrated expression of intercellular adhesion molecule-1 (ICAM-1) on 17 of 44 transitional cell cancers (TCCs) but not on normal transitional cells. ICAM-1 was frequently expressed in higher stage tumors, especially in those with abundant immune cells scattered within tumor. Analysis of infiltrating immune cells showed that they were composed mainly of T lymphocytes and a smaller number of macrophages bearing the lymphocyte function-associated antigen-1 (LFA-1). Expression of ICAM-1 on transitional cell cancer cell lines was augmented by in vitro treatment with interferon-gamma, tumor necrosis factor-alpha, and interleukin-1 beta. Furthermore, Northern blot analysis revealed higher quantities of a 3.3-kb RNA in T24 cells exposed to interferon-gamma or tumor necrosis factor-alpha. These results suggest that the expression of ICAM-1 on transitional cell cancers might be modified by cytokines produced by infiltrating immune cells, which might facilitate immune responses against cancer cells. Images Figure 1 Figure 2 Figure 5 PMID:8100398

Tomita, Y.; Watanabe, H.; Kobayashi, H.; Nishiyama, T.; Tsuji, S.; Imai, K.; Abo, T.; Fujiwara, M.; Sato, S.

1993-01-01

320

Crosstalk between sentinel and helper macrophages permits neutrophil migration into infected uroepithelium.  

PubMed

The phagocytes of the innate immune system, macrophages and neutrophils, contribute to antibacterial defense, but their functional specialization and cooperation is unclear. Here, we report that three distinct phagocyte subsets play highly coordinated roles in bacterial urinary tract infection. Ly6C(-) macrophages acted as tissue-resident sentinels that attracted circulating neutrophils and Ly6C(+) macrophages. Such Ly6C(+) macrophages played a previously undescribed helper role: once recruited to the site of infection, they produced the cytokine TNF, which caused Ly6C(-) macrophages to secrete CXCL2. This chemokine activated matrix metalloproteinase-9 in neutrophils, allowing their entry into the uroepithelium to combat the bacteria. In summary, the sentinel macrophages elicit the powerful antibacterial functions of neutrophils only after confirmation by the helper macrophages, reminiscent of the licensing role of helper T cells in antiviral adaptive immunity. These findings identify helper macrophages and TNF as critical regulators in innate immunity against bacterial infections in epithelia. PMID:24485454

Schiwon, Marzena; Weisheit, Christina; Franken, Lars; Gutweiler, Sebastian; Dixit, Akanksha; Meyer-Schwesinger, Catherine; Pohl, Judith-Mira; Maurice, Nicholas J; Thiebes, Stephanie; Lorenz, Kristina; Quast, Thomas; Fuhrmann, Martin; Baumgarten, Georg; Lohse, Martin J; Opdenakker, Ghislain; Bernhagen, Jürgen; Bucala, Rick; Panzer, Ulf; Kolanus, Waldemar; Gröne, Hermann-Josef; Garbi, Natalio; Kastenmüller, Wolfgang; Knolle, Percy A; Kurts, Christian; Engel, Daniel R

2014-01-30

321

Lipid A binding sites in membranes of macrophage tumor cells  

SciTech Connect

Lipopolysaccharide affects a variety of eukaryotic cells and mammalian organisms. These actions are involved in the pathogenesis of Gram-negative septicemia. Many of the actions of lipopolysaccharide are believed to be caused by its active moiety, lipid A. Our laboratory has previously identified a bioactive lipid A precursor, termed lipid IVA, which can be labeled with 32P of high specific activity and purified. In this work we have used the labeled probe, 4'-32P-lipid IVA, to develop a novel assay for the specific binding of lipid IVA to whole cells. We have also demonstrated its use in a ligand blotting assay of immobilized cellular proteins. Using the whole cell assay, we show that 4'-32P-lipid IVA specifically binds to RAW 264.7 macrophage-like cultured cells. The binding is saturable, is inhibited with excess unlabeled lipid IVA, and is proteinase K-sensitive. It displays cellular and pharmacological specificity. Using the ligand blotting assay, we show that several RAW 264.7 cell proteins can bind 4'-32P-lipid IVA. The two principal binding proteins have Mr values of 31 and 95 kDa, as judged by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Fractionation studies indicate that the 31-kDa protein is enriched in the nuclear fraction and may be a histone, whereas the 95-kDa protein is enriched in the membrane fraction. The binding assays that we have developed should lead to a clearer understanding of lipid A/animal cell interactions.

Hampton, R.Y.; Golenbock, D.T.; Raetz, C.R.

1988-10-15

322

IL-35-producing B cells are critical regulators of immunity during autoimmune and infectious diseases.  

PubMed

B lymphocytes have critical roles as positive and negative regulators of immunity. Their inhibitory function has been associated primarily with interleukin 10 (IL-10) because B-cell-derived IL-10 can protect against autoimmune disease and increase susceptibility to pathogens. Here we identify IL-35-producing B cells as key players in the negative regulation of immunity. Mice in which only B cells did not express IL-35 lost their ability to recover from the T-cell-mediated demyelinating autoimmune disease experimental autoimmune encephalomyelitis (EAE). In contrast, these mice displayed a markedly improved resistance to infection with the intracellular bacterial pathogen Salmonella enterica serovar Typhimurium as shown by their superior containment of the bacterial growth and their prolonged survival after primary infection, and upon secondary challenge, compared to control mice. The increased immunity found in mice lacking IL-35 production by B cells was associated with a higher activation of macrophages and inflammatory T cells, as well as an increased function of B cells as antigen-presenting cells (APCs). During Salmonella infection, IL-35- and IL-10-producing B cells corresponded to two largely distinct sets of surface-IgM(+)CD138(hi)TACI(+)CXCR4(+)CD1d(int)Tim1(int) plasma cells expressing the transcription factor Blimp1 (also known as Prdm1). During EAE, CD138(+) plasma cells were also the main source of B-cell-derived IL-35 and IL-10. Collectively, our data show the importance of IL-35-producing B cells in regulation of immunity and highlight IL-35 production by B cells as a potential therapeutic target for autoimmune and infectious diseases. This study reveals the central role of activated B cells, particularly plasma cells, and their production of cytokines in the regulation of immune responses in health and disease. PMID:24572363

Shen, Ping; Roch, Toralf; Lampropoulou, Vicky; O'Connor, Richard A; Stervbo, Ulrik; Hilgenberg, Ellen; Ries, Stefanie; Dang, Van Duc; Jaimes, Yarúa; Daridon, Capucine; Li, Rui; Jouneau, Luc; Boudinot, Pierre; Wilantri, Siska; Sakwa, Imme; Miyazaki, Yusei; Leech, Melanie D; McPherson, Rhoanne C; Wirtz, Stefan; Neurath, Markus; Hoehlig, Kai; Meinl, Edgar; Grützkau, Andreas; Grün, Joachim R; Horn, Katharina; Kühl, Anja A; Dörner, Thomas; Bar-Or, Amit; Kaufmann, Stefan H E; Anderton, Stephen M; Fillatreau, Simon

2014-03-20

323

Roles of IFN-? and ?? T Cells in Protective Immunity Against Blood-Stage Malaria  

PubMed Central

Malaria is caused by infection with Plasmodium parasites. Various studies with knockout mice have indicated that IFN-? plays essential roles in protective immunity against blood-stage Plasmodium infection. However, after Plasmodium infection, increased IFN-? production by various types of cells is involved not only in protective immunity, but also in immunopathology. Recent reports have shown that IFN-? acts as a pro-inflammatory cytokine to induce not only the activation of macrophages, but also the generation of uncommon myelolymphoid progenitor cells after Plasmodium infection. However, the effects of IFN-? on hematopoietic stem cells and progenitor cells are unclear. Therefore, the regulation of hematopoiesis by IFN-? during Plasmodium infection remains to be clarified. Although there are conflicting reports concerning the significance of ?? T cells in protective immunity against Plasmodium infection, ?? T cells may respond to infection and produce IFN-? as innate immune cells in the early phase of blood-stage malaria. Our recent studies have shown that ?? T cells express CD40 ligand and produce IFN-? after Plasmodium infection, resulting in the enhancement of dendritic cell activation as part of the immune response to eliminate Plasmodium parasites. These data suggest that the function of ?? T cells is similar to that of NK cells. Although several reports suggest that ?? T cells have the potential to act as memory cells for various infections, it remains to be determined whether memory ?? T cells are generated by Plasmodium infection and whether memory ?? T cells can contribute to the host defense against re-infection with Plasmodium. Here, we summarize and discuss the effects of IFN-? and the various functions of ?? T cells in blood-stage Plasmodium infection. PMID:24009610

Inoue, Shin-Ichi; Niikura, Mamoru; Mineo, Shoichiro; Kobayashi, Fumie

2013-01-01

324

Neuroendocrine hormones suppress macrophage-mediated lysis of herpes simplex virus-infected cells.  

PubMed

Herpes simplex viruses (HSV) remain latent in sensory and peripheral ganglia and can be reactivated to cause recurrent HSV infections. Recent evidence has suggested that stress can induce an immunosuppressive state and increase the frequency and severity of recurrent herpes infections. Because macrophages play a central role in the host defense against HSV, the effects of stress-related neuroendocrine hormones on macrophage-HSV interactions were examined. Norepinephrine and epinephrine blocked the capacity of recombinant interferon-gamma (IFN-gamma) to activate murine macrophages to a cytotoxic state capable of selectively killing HSV-infected cells. In contrast, ACTH, dopamine, serotonin, and beta-endorphin had no effect. The suppression of IFN-gamma-induced, macrophage-mediated lysis of HSV-infected cells occurred concomitantly with a marked increase in macrophage intracellular cyclic AMP levels. Moreover, exogenous administration of dibutyryl cyclic AMP blocked induction of macrophage-mediated cytotoxicity, suggesting that the neurohormones were modulating macrophage function via an adrenergic receptor-mediated system. These findings demonstrate that selective stress-related neurohormones modify the cytolytic activity of macrophages against virus-infected cells and suggest a possible neuroendocrine-immunologic basis for the recurrence of HSV infection. PMID:3001183

Koff, W C; Dunegan, M A

1986-01-01

325

Cell surface changes in the Candida albicans mitochondrial mutant goa1? are associated with reduced recognition by innate immune cells.  

PubMed

We have previously characterized several fungal-specific proteins from the human pathogen Candida albicans that either encode subunits of mitochondria Complex I (CI) of the electron transport chain (ETC) or regulate CI activity (Goa1p). Herein, the role of energy production and cell wall gene expression is investigated in the mitochondria mutant goa1?. We show that downregulation of cell wall-encoding genes in the goa1? results in sensitivity to cell wall inhibitors such as Congo red and Calcofluor white, reduced phagocytosis by a macrophage cell line, reduced recognition by macrophage receptors, and decreased expression of cytokines such as IL-6, IL-10 and IFN-?. In spite of the reduced recognition by macrophages, the goa1? is still killed to the same extent as control strains. We also demonstrate that expression of the epithelial cell receptors E-cadherin and EGFR is also reduced in the presence of goa1?. Together, our data demonstrate the importance of mitochondria in the expression of cell wall biomolecules and the interaction of C.?albicans with innate immune and epithelial cells. Our underlying premise is thatmitochondrial proteins such as Goa1p and other fungal-specific mitochondrial proteins regulate critical functions in cell growth and in virulence. As such, they remain as valid drug targets for antifungal drug discovery. PMID:23490206

She, Xiaodong; Zhang, Lulu; Chen, Hui; Calderone, Richard; Li, Dongmei

2013-09-01

326

Cell-Mediated Immunity in Epidermodysplasia verruciformis  

Microsoft Academic Search

Investigations were performed in 6 cases of epidermodysplasia verruciformis and 2 healthy family members. Nonspecific cell-mediated immunity (CMI) was studied by measuring response to phytohemagglutinin (PHA) and concanavalin A (Con A), percentages of E- and EAC-rosette-forming lymphocytes, bacterial skin tests, and allergic reactions to dinitrochloro-benzene (DNCB). Impairment of CMI was manifested by reduction in the percentage of E rosettes, and

S. Jablonska; A. Langner; S. Obalek; M. Haftek; M. Proniewska

1976-01-01

327

Unique gene expression profiles of human macrophages and dendritic cells to phylogenetically distinct parasites.  

PubMed

Monocyte-derived dendritic cells (DCs) and macrophages (Ms) generated in vitro from the same individual blood donors were exposed to 5 different pathogens, and gene expression profiles were assessed by microarray analysis. Responses to Mycobacterium tuberculosis and to phylogenetically distinct protozoan (Leishmania major, Leishmania donovani, Toxoplasma gondii) and helminth (Brugia malayi) parasites were examined, each of which produces chronic infections in humans yet vary considerably in the nature of the immune responses they trigger. In the absence of microbial stimulation, DCs and Ms constitutively expressed approximately 4000 genes, 96% of which were shared between the 2 cell types. In contrast, the genes altered transcriptionally in DCs and Ms following pathogen exposure were largely cell specific. Profiling of the gene expression data led to the identification of sets of tightly coregulated genes across all experimental conditions tested. A newly devised literature-based clustering algorithm enabled the identification of functionally and transcriptionally homogenous groups of genes. A comparison of the responses induced by the individual pathogens by means of this strategy revealed major differences in the functionally related gene profiles associated with each infectious agent. Although the intracellular pathogens induced responses clearly distinct from the extracellular B malayi, they each displayed a unique pattern of gene expression that would not necessarily be predicted on the basis of their phylogenetic relationship. The association of characteristic functional clusters with each infectious agent is consistent with the concept that antigen-presenting cells have prewired signaling patterns for use in the response to different pathogens. PMID:12663451

Chaussabel, Damien; Semnani, Roshanak Tolouei; McDowell, Mary Ann; Sacks, David; Sher, Alan; Nutman, Thomas B

2003-07-15

328

Nanotube sensors Probing Macrophage Activity with Carbon-Nanotube  

E-print Network

cellular activity. As part of the immune system, macrophages can ingest and digest pathogens in a process devices is placed in a home- built flow-cell on top of a Peltier element to maintain the temperature

Dekker, Cees

329

In Vitro Cytotoxicity of Silver Nanomaterials in Murine Macrophages  

EPA Science Inventory

Silver nanomaterials are increasingly used as antimicrobial agents in a variety of products. Although there is considerable potential for human exposure to these nanomaterials, little is known about the health risks associated with their use. Macrophages are prominent immune cell...

330

Immune Surveillance of Unhealthy Cells by Natural Killer cells  

PubMed Central

Pathogenic and oncogenic insults result in the induction of intrinsic defense mechanisms such as cell death pathways and senescence, and extrinsic pathways that mobilize immune responses to destroy unhealthy cells. Both protective mechanisms presumably evolved to limit the damage these insults could inflict on the host. After viral infection or malignant transformation, unhealthy cells can be directly sensed by natural killer (NK) and some T cells via the activating receptor NKG2D. All NK cells and subsets of T cells express NKG2D. The NKG2D/ligand system represents a major recognition mechanism for detection and elimination of unhealthy cells. Here we discuss different pathways, including stress pathways, that are responsible for cell surface display of ligands for NKG2D, which are self-proteins that are minimally expressed by normal cells. We also discuss new results indicating that efficient elimination of tumor cells that display NKG2D ligands depends on the recruitment of NK cells and other immune cells to the tumor, which can be regulated by distinct mechanisms, including the p53-dependent production of chemokines by senescent tumors. The cooperative effect of pathways that induce the display NKG2D ligands and distinct pathways that mobilize immune cells provides a higher degree of specificity to the NK cell response. PMID:24135717

Iannello, Alexandre; Raulet, David H.

2014-01-01

331

Phototherapy-treated apoptotic tumor cells induce pro-inflammatory cytokines production in macrophage  

NASA Astrophysics Data System (ADS)

Our previous studies have demonstrated that as a mitochondria-targeting cancer phototherapy, high fluence low-power laser irradiation (HF-LPLI) induces mitochondrial superoxide anion burst, resulting in oxidative damage to tumor cells. In this study, we further explored the immunological effects of HF-LPLI-induced apoptotic tumor cells. When macrophages were co-incubated with apoptotic cells induced by HF-LPLI, we observed the increased levels of TNF-? secretion and NO production in macrophages. Further experiments showed that NF-?B was activated in macrophages after co-incubation with HF-LPLI-induced apoptotic cells, and inhibition of NF-?B activity by pyrrolidinedithiocarbamic acid (PDTC) reduced the elevated levels of TNF-? secretion and NO production. These data indicate that HF-LPLI-induced apoptotic tumor cells induce the secretion of pro-inflammatory cytokines in macrophages, which may be helpful for better understanding the biological effects of cancer phototherapy.

Lu, Cuixia; Wei, Yanchun; Xing, Da

2014-09-01

332

Three types of macrophagic cells in the mesentery of mice with special reference to LYVE-1-immunoreactive cells.  

PubMed

Immunohistochemistry using whole mount preparations of the murine mesentery revealed two types of LYVE-1-immunoreactive cells with dendritic morphology other than F4/80(+) typical macrophages.The two types of LYVE-1(+) cells were regularly distributed with constant intervals throughout the mesentery and appeared to possess their own territory. Both types of LYVE-1(+) cells were weakly or moderately immunopositive for F4/80 antibody, a marker of macrophages,while F4/80(+) round macrophages were absolutely free from the LYVE-1 immunoreactivity. Only macrophages could ingest latex particles of 20 nm in diameter 3 h after a peritoneal injection.Peritoneal administration of lipopolysaccharide (LPS) induced a rapid reduction of LYVE-1 immunoreactivity in the cells with dendritic morphology followed by an increased immunoreactivity to F4/80 antibody, and simultaneously by dynamic changes in their shape. Under normal conditions,F4/80(+) macrophages in various connective tissues expressed LYVE-1, in contrast to lack of LYVE-1 in F4/80(+) macrophages within the parenchyma of visceral organs and macrophages residing in hepatic sinusoids and pulmonary alveoli. LYVE-1 may play a role in cell adhesion and migration of macrophagic cells within connective tissues rich in hyaluronan, and loss of LYVE-1 becomes a reliable sign of activated conditions in inflammation. PMID:24573200

Zheng, Miao; Kimura, Shunsuke; Nio-Kobayashi, Junko; Takahashi-Iwanaga, Hiromi; Iwanaga, Toshihiko

2014-01-01

333

Metabolism of stromal and immune cells in health and disease.  

PubMed

Cancer cells have been at the centre of cell metabolism research, but the metabolism of stromal and immune cells has received less attention. Nonetheless, these cells influence the progression of malignant, inflammatory and metabolic disorders. Here we discuss the metabolic adaptations of stromal and immune cells in health and disease, and highlight how metabolism determines their differentiation and function. PMID:25008522

Ghesquière, Bart; Wong, Brian W; Kuchnio, Anna; Carmeliet, Peter

2014-07-10

334

Tumors disable immune cells by using up sugar  

Cancer.gov

Cancer cells’ appetite for sugar may have serious consequences for immune cell function, researchers at Washington University School of Medicine in St. Louis have learned. The scientists found that when they kept sugar away from critical immune cells called T cells, the cells no longer produced interferon gamma, an inflammatory compound important for fighting tumors and some kinds of infection.

335

Immune Responses to Stem Cells and Cancer Stem Cells  

Microsoft Academic Search

\\u000a The demonstrated capacity and potential of pluripotent stem cells to repair the damaged tissues holds great promise in development\\u000a of novel cell replacement therapeutics for treating various chronic and degenerative diseases. However, previous reports show\\u000a that stem cell therapy, in autologous and allogeneic settings, triggers immune responses to stem cells as shown by lymphocyte\\u000a infiltration and inflammation. Therefore, an important

Xiao-Feng Yang; Hong Wang

336

Macrophages and Kidney Disease: Macrophages and Immunological Inflammation of the kidney  

PubMed Central

Monocyte derived tissue effector cells, macrophages, are present in large numbers in all forms of kidney disease with inflammation. Their roles in inflammation and the molecular effectors of macrophage function have been difficult to decipher. With the advent of modern genetic tools and mouse models of human disease, great insight into monocyte/macrophage biology has been forthcoming. In this review we will place macrophage study in its historical context, define immunological diseases of the kidney, and broaden its definition to encompass current thinking of the immune response to kidney injury, highlight key advances of the study of monocyte/macrophages in kidney diseases, and identify new therapeutic pathways and targets that hinge around macrophage function. Here we advance the case that targeting macrophage activation and phenotype is leading to new therapies in treatment of many acute and chronic kidney diseases. PMID:20620669

Duffield, Jeremy S.

2010-01-01

337

Multiple signaling pathways contribute to synergistic TLR ligand-dependent cytokine gene expression in human monocyte-derived macrophages and dendritic cells  

Microsoft Academic Search

TLRs are innate immune receptors that recognize pathogen-associated structures. Binding of ligands to different TLRs can induce the produc- tion of proinflammatory cytokines in a synergistic manner. We have analyzed the molecular mecha- nisms of synergy in TLR ligand-stimulated human monocyte-derived macrophages and dendritic cells (moDCs). Stimulation of moDCs with the TLR8 ligand together with the TLR3 or TLR4 ligand

Sanna M. Makela; Mari Strengell; Taija E. Pietila; Pamela Osterlund; Ilkka Julkunen

2009-01-01

338

Expression of macrophage-lymphocyte Fc receptors in Madin-Darby canine kidney cells: polarity and transcytosis differ for isoforms with or without coated pit localization domains  

Microsoft Academic Search

Many cells of the immune system and cer- tain epithelia express receptors for the Fc domain of IgG (FcR). On mouse macrophages and lymphocytes, two distinct receptor isoforms have been identified, designated FcRII-B1 and FcRII-B2. The isoforms are identical except for an in-frame insertion of 47 amino acids in the cytoplasmic tail of FcRII-B1 that blocks its ability to be

Walter Hunziker; Ira Mellman

1989-01-01

339

PspA and PspC Minimize Immune Adherence and Transfer of Pneumococci from Erythrocytes to Macrophages through Their Effects on Complement Activation  

Microsoft Academic Search

Pneumococcal surface protein A (PspA) and PspC are important virulence factors. Their absence has been shown to allow improved clearance of pneumococci from the blood of mice and to decrease pneumococcal virulence. In the presence of antibody and complement, pneumococci attach to erythrocytes in a process called immune adherence (IA), which facilitates their delivery to, and eventual phagocytosis by, macrophages.

Jie Li; David T. Glover; Alexander J. Szalai; Susan K. Hollingshead; David E. Briles

2007-01-01

340

Macrophages induce COX-2 expression in breast cancer cells: role of IL-1? autoamplification.  

PubMed

Tumor-associated macrophages and high levels of cyclooxygenase-2 (COX-2) are associated with poor prognosis in breast cancer patients, but their potential interdependence has not been evaluated. The objective of this study was to determine whether macrophages regulate COX-2 expression in breast cancer cells. For this purpose, THP-1 cells were cocultured with HCC1954 breast cancer cells. Coculture led to increased COX-2 expression in the HCC1954 cells and elevated prostaglandin E(2) levels in conditioned media. Similar results were observed when THP-1 cells were incubated with HCC1937 breast cancer cells or when human monocyte-derived macrophages were cocultured with HCC1954 cells. Coculture triggered production of reactive oxygen species (ROS) in HCC1954 cells. COX-2 induction was blocked in cells preincubated with an reduced nicotinamide adenine dinucleotide phosphate (NADPH) oxidase inhibitor or by silencing p67PHOX, a subunit of NADPH oxidase. ROS production triggered activation of Src and mitogen-activated protein kinases (MAPKs). Blocking Src or MAPK activities or antagonizing the activator protein-1 (AP-1) transcription factor attenuated COX-2 induction in HCC1954 cells. Coculture caused rapid induction of interleukin-1? (IL-1?) in both breast cancer cells and macrophages. Increased IL-1? expression was blocked by an interleukin-1 receptor antagonist (IL-1Ra), suggesting autocrine and paracrine effects. Importantly, macrophage-induced COX-2 expression was blocked in HCC1954 cells preincubated with IL-1Ra or anti-IL-1? IgG. Together, these results indicate that macrophage-mediated induction of COX-2 in breast cancer cells is a consequence of IL-1?-mediated stimulation of ROS?Src?MAPK?AP-1 signaling. IL-1?-dependent induction of COX-2 in breast cancer cells provides a mechanism whereby macrophages contribute to tumor progression and potential therapeutic targets in breast cancer. PMID:21310944

Hou, Zhe; Falcone, Domenick J; Subbaramaiah, Kotha; Dannenberg, Andrew J

2011-05-01

341

Monocyte and macrophage heterogeneity in the heart  

PubMed Central

Monocytes and macrophages are innate immune cells that reside and accumulate in the healthy and injured heart. The cells and their subsets pursue distinct functions in steady state and disease, and their tenure may range between hours to months. Some subsets are highly inflammatory, while others support tissue repair. This review discusses current concepts of lineage relationships and systems’ cross talk, highlights open questions, and describes tools for studying monocyte and macrophage subsets in the murine and human heart. PMID:23743228

Nahrendorf, Matthias; Swirski, Filip K.

2013-01-01

342

Interaction of monocytes/macrophages with ovarian cancer cells promotes angiogenesis in vitro.  

PubMed

It has been established that macrophages and endothelial cells infiltrate peritoneum in the vicinity of tumor implants of epithelial ovarian cancer (EOC). This study investigates whether the interaction of ovarian cancer cells and tumor-associated macrophages could promote the involvement of endothelial cells in angiogenesis. Macrophage phenotypes were detected by fluorescence-activated cell sorting, and cytokine/chemokine secretion was measured by enzyme linked immunosorbent assay. The effect of co-culture of ovarian cancer cells and tumor-associated macrophage (TAM) cells on endothelial cell migration and tube formation was investigated. Signaling pathway mediators were also evaluated for their potential roles in endothelial cell activation by ovarian cancer cells co-cultured with TAM cells. Our results showed that higher expression of interleukin-8 (IL-8) expression associated with 54.26 ± 34.46% of TAM infiltration of peritoneum was significantly higher than 16.58 ± 17.74% of CD3(+) T-cell by immunofluorescence co-staining and confocal microscopy. THP-1 cells exhibited M2-polarized phenotype markers with high proportion of CD68(+) , CD206(+) and CD204(+) markers after phorbol 12-myristate 13-acetate (PMA) treatment, After co-culturing with TAM cells in a transwell chamber system, EOC cells (SKOV3) increased their IL-8 expression at the level of mRNA and protein. After exposure to the conditioned medium obtained by co-culturing TAM and SKOV3 cells, the migration and tube formation of endothelial cells were enhanced significantly. Furthermore, the upregulation of IL-8 expression in ovarian cancer cells induced by macrophages could be inhibited by pyrollidine dithiocarbamate, an inhibitor of nuclear factor (NF)- ?B signal pathway. We suggest that the interaction of ovarian cancer cells and tumor-associated macrophages enhances the ability of endothelial cells to promote the progression of ovarian cancer. PMID:23347208

Wang, Xipeng; Zhao, Xiaobo; Wang, Kai; Wu, Li; Duan, Tao

2013-04-01

343

Role of Dendritic Cells in Immune Dysfunction  

NASA Technical Reports Server (NTRS)

The specific aims of the project were: (1) Application of the NASA bioreactor to enhance cytokine-regulated proliferation and maturation of dendritic cells (DC). (2) Compare the frequency and function of DC in normal donors and immunocompromised cancer patients. (3) Analyze the effectiveness of cytokine therapy and DC-assisted immunotherapy (using bioreactor-expanded DC) in a murine model of experimental fungal disease. Our investigations have provided new insight into DC immunobiology and have led to the development of methodology to evaluate DC in blood of normal donors and patients. Information gained from these studies has broadened our understanding of possible mechanisms involved in the immune dysfunction of space travelers and earth-bound cancer patients, and could contribute to the design of novel therapies to restore/preserve immunity in these individuals. Several new avenues of investigation were also revealed. The results of studies completed during Round 2 are summarized.

Savary, Cherylyn A.

1998-01-01

344

Lentiviral Vectors for Immune Cells Targeting  

PubMed Central

Lentiviral vectors are efficient gene delivery vehicles suitable for delivering long-term transgene expression in various cell types. Engineering lentiviral vectors to have the capacity to transduce specific cell types is of great interest to advance the translation of lentiviral vectors towards the clinic. Here we provide an overview of innovative approaches to target lentiviral vectors to cells of the immune system. In this overview we distinguish between two types of lentiviral vector targeting strategies: 1) targeting of the vectors to specific cells by lentiviral vector surface modifications, and 2) targeting at the level of transgene transcription by insertion of tissue-specific promoters to drive transgene expression. It is clear that each strategy is of enormous value but ultimately combining these approaches may help reduce the effects of off-target expression and improve the efficiency and saftey of lentiviral vectors for gene therapy. PMID:20085508

Froelich, Steven; Tai, April; Wang, Pin

2009-01-01

345

Functional deficiencies of granulocyte-macrophage colony stimulating factor and interleukin-3 contribute to insulitis and destruction of ? cells  

PubMed Central

The pathogenesis of type 1 diabetes (T1D) involves the immune-mediated destruction of insulin-producing ? cells in the pancreatic islets of Langerhans. Genetic analysis of families with a high incidence of T1D and nonobese diabetic (NOD) mice, a prototypical model of the disorder, uncovered multiple susceptibility loci, although most of the underlying immune defects remain to be delineated. Here we report that aged mice doubly deficient in granulocyte-macrophage colony-stimulating factor (GM-CSF) and interleukin-3 (IL-3) manifest insulitis, destruction of insulin-producing ? cells, and compromised glucose homeostasis. Macrophages from mutant mice produce increased levels of p40 after LPS stimulation, whereas concurrent ablation of interferon-? (IFN-?) ameliorates the disease. The administration of antibodies that block cytotoxic T lymphocyte associated antigen-4 (CTLA-4) to young mutant mice precipitates the onset of insulitis and hyperglycemia. These results, together with previous reports of impaired hematopoietic responses to GM-CSF and IL-3 in patients with T1D and in NOD mice, indicate that functional deficiencies of these cytokines contribute to diabetes. PMID:17483299

Enzler, Thomas; Gillessen, Silke; Dougan, Michael; Allison, James P.; Neuberg, Donna; Oble, Darryl A.; Mihm, Martin

2007-01-01

346

A novel rat monoclonal antibody reactive with murine tumoricidal Kupffer cells and activated peritoneal macrophages from BCG-infected mice.  

PubMed Central

A rat monoclonal antibody, termed 1A2.10D and raised against mouse BCG-activated peritoneal-macrophages, was used to detect antigenic determinant(s) on mouse tumoricidal activated peritoneal and liver macrophages from BCG-infected mice by indirect immunofluorescence flow cytometry and immunoblot analysis. This antibody was of the rat IgG2b subclass and not cytolytic to BCG-activated macrophages in the presence of rabbit complement. The antigen(s) was expressed on tumoricidal activated peritoneal and liver macrophages from BCG-infected mice and some macrophage cell lines. Its expression could not be detected on resident peritoneal cells, peritoneal exudate cells containing non- or low tumoricidal macrophages, thymocytes, resting bone marrow cells, normal spleen cells, various established mouse tumour cells or one macrophage cell line. Immunoblot analysis showed the antibody to bind to one major protein of 56,000 MW, and to be expressed on the peritoneal and liver macrophages from BCG-infected mice. Using this antibody and a fluorescence-activated cell sorter, selection was made of antibody-positive or -negative macrophages from BCG-infected mice to examine their tumour killing activity. The antibody-positive macrophages clearly showed higher tumour killing activity than the negative macrophages. Images Figure 3 PMID:2420709

Someya, A

1986-01-01

347

Effects of in vitro nickel exposure on the macrophage-mediated immune functions of rainbow trout (Oncorhynchus mykiss)  

SciTech Connect

Nickel is occurs naturally in the geophysical environment. It has become a common byproduct of industrialization. Nickel is released into the atmosphere and coal-burning power plants and trash incinerators, and is also discharged into waste water by industries which convert scrap or new nickel into alloys. The effluent that spreads to streams, rivers, and lakes may disrupt the integrity of the aquatic environment. Excess nickel contamination is hazardous to aquatic ecosystems due to its existence and bioaccumulation. While the adverse health effects associated with nickel exposure have been extensively examined in mammalian systems, very little is known concerning nickel's effects on aquatic organisms. Although trace amounts of nickel are necessary for maintaining the metabolic homeostasis of some vertebrate species, larger amounts of nickel have been shown to be toxic. In addition to being both genotoxic and carcinogenic, nickel modulates immunological functions in a variety of mammalian species. The toxic effects of nickel on the numbers, activity, and ultrastructure of macrophages (M[o]) have been well-studied. A number of other toxic metals such as copper, manganese, and cadmium modulate the immune responses of fish. To appraise the immunomodulating potential of nickel on fish, and to begin to establish baseline parameters of altered immune function as potential biomarkers of in vivo nickel exposure, elicited peritoneal macrophages from rainbow trout (Oncorhynchus mykiss) were treated in vitro with increasing concentrations of nickel sulfate (NiSO[sub 4]). Following exposure, M[o] activities important for maintaining host immunocompetence were evaluated and these include; mobility (random and stimulus-directed), production of reactive oxygen intermediates (ROI), acid phosphatase activity, and phagocytosis. 20 refs., 3 figs.

Bowser, D.H.; Frenkel, K.; Zelikoff, J.T. (New York Univ. Medical Center, NY (United States))

1994-03-01

348

Recombinant interleukin-4-treated macrophages, epithelioid cell surrogates, harbor and arrest Mycobacterium avium multiplication in vitro.  

PubMed

Our group has previously described that murine peritoneal macrophages treated in vitro for 7 days with recombinant interleukin-4 (rIL-4) acquire morphological and functional characteristics of epithelioid cells (ECs) found in granulomatous lesions. Although EC function has not been clarified so far, it has been suggested that these cells could present antigens and control multiplication of mycobacteria. These aspects have been addressed here using in vitro EC surrogates. Using immunocytochemistry and immunofluorescence methods, we have observed an increased expression of CD11b, CD54, CD86 and CD40 molecules on rIL-4-treated macrophages when compared to untreated ones. Cytokine-treated cells were less phagocytic for latex beads (P<0.03) and more pinocytic for dextran particles than untreated macrophages. T-cell lymphoproliferation assays using ovalbumin (OVA) and Mycobacterium avium as antigens showed that both cultured macrophages were equally efficient as antigen presenting cells (APCs). However, M. avium antigens were better presented in vivo by EC surrogates (P<0.01). Both macrophage cultures were similarly infected by M. avium. However, while the infection level was maintained in the cytokine-treated population, untreated macrophages showed a progressive increase in the number of bacilli/cell with time (P<0.01) and a reduction of about 65% in cell population. After 96 h of M. avium infection, untreated cells secreted higher amounts of tumor necrosis factor-alpha (P<0.005) while rIL-4-treated macrophages showed higher, although not significant, transforming growth factor-beta production. Also, EC surrogates produced less nitric oxide than control macrophages (P<0.05). Hence, EC surrogates restrain M. avium growth and act as APCs in vitro and in vivo. PMID:16515875

Chinen, Ludmilla T D; Cipriano, Ivone M; de Oliveira, Rosângela S; Leão, Sylvia C; Mariano, Mario; Carneiro, Célia R Whitaker

2006-04-01

349

Immune-Pineal Axis: Nuclear Factor ?B (NF-?B) Mediates the Shift in the Melatonin Source from Pinealocytes to Immune Competent Cells  

PubMed Central

Pineal gland melatonin is the darkness hormone, while extra-pineal melatonin produced by the gonads, gut, retina, and immune competent cells acts as a paracrine or autocrine mediator. The well-known immunomodulatory effect of melatonin is observed either as an endocrine, a paracrine or an autocrine response. In mammals, nuclear translocation of nuclear factor ?-light-chain-enhancer of activated B cells (NF-?B) blocks noradrenaline-induced melatonin synthesis in pinealocytes, which induces melatonin synthesis in macrophages. In addition, melatonin reduces NF-?B activation in pinealocytes and immune competent cells. Therefore, pathogen- or danger-associated molecular patterns transiently switch the synthesis of melatonin from pinealocytes to immune competent cells, and as the response progresses melatonin inhibition of NF-?B activity leads these cells to a more quiescent state. The opposite effect of NF-?B in pinealocytes and immune competent cells is due to different NF-?B dimers recruited in each phase of the defense response. This coordinated shift of the source of melatonin driven by NF-?B is called the immune-pineal axis. Finally, we discuss how this concept might be relevant to a better understanding of pathological conditions with impaired melatonin rhythms and hope it opens new horizons for the research of side effects of melatonin-based therapies. PMID:23708099

Markus, Regina P; Cecon, Erika; Pires-Lapa, Marco Antonio

2013-01-01

350

Macrophage Inhibition of Lymphocyte and Tumor Cell Growth Is Mediated by 25–Hydroxycholesterol in the Cell Membrane  

Microsoft Academic Search

We have previously reported that a lipid molecule in the membrane fraction of cloned macrophage hybridomas inhibited the growth of lymphocytes and several tumor cell lines. In this study, the inhibitory lipid molecule in the membrane fraction of macrophages was analyzed by thin–layer chromatography and identified as 25–hydroxycholesterol, a family of oxysterols. This conclusion was confirmed by analysis using gas

Hiroshi Kato; Atsuko Horino; Maiko Taneichi; Naoyuki Fukuchi; Yuzuru Eto; Hiroshi Ushijima; Katsutoshi Komuro; Tetsuya Uchida

1998-01-01

351

Corticosteroid effects on COPD alveolar macrophages: dependency on cell culture methodology.  

PubMed

It is unclear whether cell culture methodology affects the corticosteroid sensitivity of chronic obstructive pulmonary disease (COPD) alveolar macrophages. We compared the effect of a short and a long isolation procedure on corticosteroid inhibition of lipopolysaccharide (LPS) stimulated cytokine release from COPD alveolar macrophages. We also investigated signalling pathways associated with macrophage activation during cell isolation. Macrophages cultured using a short isolation protocol released higher unstimulated levels of tumour necrosis factor (TNF)-? and chemokine C-X-C motif ligand (CXCL) 8; these macrophages were less sensitive to corticosteroid inhibition of LPS stimulated TNF-? and CXCL8 release when compared to a long isolation procedure. This was associated with increased p38 mitogen activated kinase (MAPK) activation. The p38 MAPK inhibitor, BIRB-796, significantly reduced unstimulated cytokine release. A key finding of this study was that both cell culture methods showed no difference in the corticosteroid sensitivity between COPD and control macrophages. We conclude that the culture of alveolar macrophages using a short isolation procedure alters cytokine production through p38 MAPK activation; this is associated with a change in corticosteroid sensitivity. PMID:24530567

Higham, Andrew; Lea, Simon; Ray, David; Singh, Dave

2014-03-01

352

Dynamics of Salmonella infection of macrophages at the single cell level  

PubMed Central

Salmonella enterica causes a range of diseases. Salmonellae are intracellular parasites of macrophages, and the control of bacteria within these cells is critical to surviving an infection. The dynamics of the bacteria invading, surviving, proliferating in and killing macrophages are central to disease pathogenesis. Fundamentally important parameters, however, such as the cellular infection rate, have not previously been calculated. We used two independent approaches to calculate the macrophage infection rate: mathematical modelling of Salmonella infection experiments, and analysis of real-time video microscopy of infection events. Cells repeatedly encounter salmonellae, with the bacteria often remain associated with the macrophage for more than ten seconds. Once Salmonella encounters a macrophage, the probability of that bacterium infecting the cell is remarkably low: less than 5%. The macrophage population is heterogeneous in terms of its susceptibility to the first infection event. Once infected, a macrophage can undergo further infection events, but these reinfection events occur at a lower rate than that of the primary infection. PMID:22552918

Gog, Julia R.; Murcia, Alicia; Osterman, Natan; Restif, Olivier; McKinley, Trevelyan J.; Sheppard, Mark; Achouri, Sarra; Wei, Bin; Mastroeni, Pietro; Wood, James L. N.; Maskell, Duncan J.; Cicuta, Pietro; Bryant, Clare E.

2012-01-01

353

Two biochemically distinct lipophosphoglycans from Leishmania braziliensis and Leishmania infantum trigger different innate immune responses in murine macrophages  

PubMed Central

Background The dominant, cell surface lipophosphoglycan (LPG) of Leishmania is a multifunctional molecule involved in the interaction with vertebrate and invertebrate hosts. Although the role of LPG on infection has been extensively studied, it is not known if LPG interspecies variations contribute to the different immunopathologies of leishmaniases. To investigate the issue of interspecies polymorphisms, two Leishmania species from the New World that express structural variations of side chains of LPG repeat units were examined. In this context, the procyclic form of L. braziliensis LPG (strain M2903), is devoid of side chains, while the L. infantum LPG (strain BH46) has up to three glucoses residues in the repeat units. Methods Mice peritoneal macrophages from Balb/c, C57BL/6 and knock-out (TLR2 ?/?, TLR4 ?/?) were primed with IFN-? and stimulated with purified LPG from both species. Nitric oxide and cytokine production, MAPKs (ERK, p38 and JNK) and NF-kB activation were evaluated. Results Macrophages stimulated with L. braziliensis LPG, had a higher TNF-?, IL-1?, IL-6 and NO production than those stimulated with that of L. infantum. Furthermore, the LPGs from the two species resulted in differential kinetics of signaling via MAPK activation. L. infantum LPG exhibited a gradual activation profile, whereas L. braziliensis LPG showed a sharp but transient activation. L. braziliensis LPG was able to activate NF-kB. Conclusion These data suggest that two biochemically distinct LPGs were able to differentially modulate macrophage functions. PMID:23497381

2013-01-01

354

HIV-1 infection of macrophages dysregulates innate immune responses to Mycobacterium tuberculosis by inhibition of interleukin-10.  

PubMed

Human immunodeficiency virus (HIV)-1 and Mycobacterium tuberculosis (M. tuberculosis) both target macrophages, which are key cells in inflammatory responses and their resolution. Therefore, we tested the hypothesis that HIV-1 may modulate macrophage responses to coinfection with M. tuberculosis. HIV-1 caused exaggerated proinflammatory responses to M. tuberculosis that supported enhanced virus replication, and were associated with deficient stimulus-specific induction of anti-inflammatory interleukin (IL)-10 and attenuation of mitogen-activated kinase signaling downstream of Toll-like receptor 2 and dectin-1 stimulation. Our in vitro data were mirrored by lower IL-10 and higher proinflammatory IL-1? in airway samples from HIV-1-infected patients with pulmonary tuberculosis compared with those with non-tuberculous respiratory tract infections. Single-round infection of macrophages with HIV-1 was sufficient to attenuate IL-10 responses, and antiretroviral treatment of replicative virus did not affect this phenotype. We propose that deficient homeostatic IL-10 responses may contribute to the immunopathogenesis of active tuberculosis and propagation of virus infection in HIV-1/M. tuberculosis coinfection. PMID:24265436

Tomlinson, Gillian S; Bell, Lucy C K; Walker, Naomi F; Tsang, Jhen; Brown, Jeremy S; Breen, Ronan; Lipman, Marc; Katz, David R; Miller, Robert F; Chain, Benjamin M; Elkington, Paul T G; Noursadeghi, Mahdad

2014-04-01

355

CCR6, a CC Chemokine Receptor that Interacts with Macrophage Inflammatory Protein 3? and Is Highly Expressed in Human Dendritic Cells  

PubMed Central

Dendritic cells initiate immune responses by ferrying antigen from the tissues to the lymphoid organs for presentation to lymphocytes. Little is known about the molecular mechanisms underlying this migratory behavior. We have identified a chemokine receptor which appears to be selectively expressed in human dendritic cells derived from CD34+ cord blood precursors, but not in dendritic cells derived from peripheral blood monocytes. When stably expressed as a recombinant protein in a variety of host cell backgrounds, the receptor shows a strong interaction with only one chemokine among 25 tested: the recently reported CC chemokine macrophage inflammatory protein 3?. Thus, we have designated this receptor as the CC chemokine receptor 6. The cloning and characterization of a dendritic cell CC chemokine receptor suggests a role for chemokines in the control of the migration of dendritic cells and the regulation of dendritic cell function in immunity and infection. PMID:9294138

Greaves, David R.; Wang, Wei; Dairaghi, Daniel J.; Dieu, Marie Caroline; Saint-Vis, Blandine de; Franz-Bacon, Karin; Rossi, Devora; Caux, Christophe; McClanahan, Terrill; Gordon, Siamon; Zlotnik, Albert; Schall, Thomas J.

1997-01-01

356

Lymphocyte Adhesion and Interactions with Biomaterial Adherent Macrophages and Foreign Body Giant Cells  

PubMed Central

To characterize the effects of adherent macrophages and biomaterial surface chemistries on lymphocyte adhesion and activation, lymphocytes were co-cultured with monocytes alone and together, directly and separated by a porous membrane transwell on hydrophobic, hydrophilic/neutral, hydrophilic/anionic, and hydrophilic/cationic biomaterial surfaces. Surface adherent cells were quantitatively analyzed after 3 days utilizing immunofluorescence and phase contrast imaging. After periods of 3, 7, and 10 days, secreted interferon-? (IFN-?) was quantified by ELISA. Limited direct biomaterial-adherent lymphocytes were identified regardless of the presence of macrophages or foreign body giant cells (FBGC). The majority of adherent lymphocytes, which were T cells (> 95%) rather than natural killer cells, predominantly interacted with adherent macrophages and FBGCs; greater than 90% were interacting on surfaces with higher levels of adherent macrophages and FBGCs and greater than 55% were interacting on surfaces with lower levels of macrophages and FBGCs. The hydrophilic/anionic surface promoted higher levels of macrophage- and FBGC-adherent lymphocytes but was nonselective for lymphocyte subtype interactions. The hydrophilic/neutral surface was selective for CD4+ T lymphocyte interactions while the hydrophobic surface was selective for CD8+ T lymphocyte interactions. IFN-? was produced in direct and indirect co-cultures but not in lymphocyte- and monocyte-only cultures suggesting that lymphocytes are activated via macrophage-derived cytokines rather than direct biomaterial contact. Direct lymphocyte interactions with adherent macrophages/FBGCs enhanced IFN-? production relative to indirect co-cultures. These results suggest that lymphocytes prefer interactions with adherent macrophages and FBGCs, resulting in lymphocyte activation, and these interactions can be influenced by biomaterial surface chemistries. PMID:19148923

Chang, David T.; Colton, Erica; Matsuda, Takehisa; Anderson, James M.

2008-01-01

357

Metchnikoff's Policemen--Macrophages in Development, Homeostasis and Regeneration  

PubMed Central

Over the past decade, modern genetic tools have permitted scientists to study the function of myeloid lineage cells, including macrophages, as never before. Macrophages were first detected more than a century ago as cells that ingested bacteria and other microbes, but it is now known that their functional roles are far more numerous. In this review, we focus on the prevailing functions of macrophages beyond their role in innate immunity. We highlight examples of macrophages acting as regulators of development, tissue homoeostasis, remodeling (the reorganization or renovation of existing tissues), and repair. We also detail how modern genetic tools have facilitated new insights into these mysterious cells. PMID:21890411

Stefater, James A.; Ren, Shuyu; Lang, Richard A.; Duffield, Jeremy S.

2011-01-01