bluuebunny/crossref_metadata_2025_split huggingface dataset:
Dynamics of Macrophage Cell Populations During Murine Pulmonary Tuberculosis
Authors: Gonzalez-Juarrero Mercedes , Shim Tae Sun , Kipnis Andre , Junqueira-Kipnis Ana Paula , Orme Ian M. 
Published: April 2014

AbstractThe influx of macrophages into the lungs is the major component of the granulomatous response to infection with Mycobacterium tuberculosis. In this investigation we used flow cytometric analysis to define macrophage populations entering the airways and lung tissues of infected mice. We demonstrate that by the judicious use of cell surface markers, especially CD11b and CD11c, several cell populations can be distinguished, allowing cell sorting and morphological definition. Primary populations of CD11b−/CD11c+/high were defined as alveolar macrophages, CD11bhigh/CD11c+/high as dendritic cells, and CD11b+/mid/CD11c+/mid as small macrophages or monocytes, and changes in the activation phenotype of these populations were followed over the early course of the infection. In further studies, these cell populations were compared with cells harvested during the chronic stage of the disease. During the chronic stage of infection, Ag-presenting class II molecules and activation markers were poorly expressed on dendritic, small macrophage, and monocyte cell populations, which may have important implications for the breakdown of the lesions during reactivation disease. This analytical approach may facilitate the further characterization of macrophage populations entering into the lung tissues and their relative contributions to host resistance to tuberculosis infection.
Over-Expression of Bcl-2 Provides Protection in Septic Mice by a trans Effect
Authors: Iwata Akiko , Stevenson Vicki Morgan , Minard Annie , Tasch Michael , Tupper Joan , Lagasse Eric , Weissman Irving , Harlan John M. , Winn Robert K. 
Published: April 2014

Abstract
Transgenic mice that over-express B cell leukemia/lymphomas (Bcl)-2 in myeloid cells under control of the human MRP8 promoter (hMRP8-Bcl-2) or in T lymphocytes under the Eμ promoter (Eμ-Bcl-2) were compared with C57BL/6 control mice following cecal ligation and puncture (CLP). There was a significant difference in outcome between the hMRP8-Bcl-2 and control mice with 100% survival in the hMRP8-Bcl-2 mice vs 25% survival in the control mice. In separate experiments there was a significant difference between Eμ-Bcl-2 and control mice with 87.5 and 22.2% survival, respectively. Adoptive transfer of CD11b-positive bone marrow cells from hMRP8-Bcl-2 or C57BL/6 mice to C57BL/6 mice subjected to CLP resulted in 100 and 0% survival, respectively. Adoptive transfer of CD11b-positive cells from either hMRP8-Bcl-2 or C57BL/6 mice to Rag-1−/− mice (no mature T or B cells) subjected to CLP resulted in survival of 87.5 and 12.5%, respectively. The hMRP8-Bcl-2 mice had significantly more neutrophils and fewer bacteria in the peritoneum compared with C57BL/6 mice 24 h after CLP. These experiments show that Bcl-2 over-expression is protective in CLP and that protection is independent of lymphocytes. We propose that over-expression of Bcl-2 in T cells or myeloid cells induce release of a molecule(s) that protects against death following CLP.
IL-10 Prevents Liver Necrosis During Murine Infection withTrichinella spiralis
Authors: Bliss Susan K. , Alcaraz Ana , Appleton Judith A. 
Published: April 2014

AbstractInfection with Trichinella spiralis rarely leads to significant morbidity. In this study, we show that IL-10 knockout mice infected with this parasite develop extensive areas of coagulative necrosis in the liver, and newborn larvae are required for lesion formation. Histopathological examination revealed that the hepatic inflammatory infiltrate was mixed but dominated by eosinophils. Accordingly, infected IL-10 knockout mice displayed a marked eosinophilia. IL-10 was expressed during infection in mesenteric lymph node populations and liver tissue. Analysis of cytokine profiles revealed a codominant expression of type 1 and 2 mediators that was enhanced in the absence of IL-10. Additionally, CD11c+ MHC class II+ cells were increased in mesenteric lymph nodes of IL-10 knockout mice, suggesting a possible link between IL-10 and dendritic cell trafficking. Nevertheless, there were no significant differences in mortality or parasite burdens between the strains of mice, indicating that IL-10 is necessary to control the host’s inflammatory response but does not impact establishment of the parasite. Expression of IL-10 appears to be an adaptation used by the liver to protect itself from damage caused by migrating newborn larvae.
Successful Induction of CD8 T Cell-Dependent Protection Against Malaria by Sequential Immunization with DNA and Recombinant Poxvirus of Neonatal Mice Born to Immune Mothers
Authors: Sedegah Martha , Belmonte Maria , Epstein Judith E. , Siegrist Claire-Anne , Weiss Walter R. , Jones Trevor R. , Lu Minh , Carucci Daniel J. , Hoffman Stephen L. 
Published: April 2014

Abstract
In some parts of Africa, 50% of deaths attributed to malaria occur in infants less than 8 mo. Thus, immunization against malaria may have to begin in the neonatal period, when neonates have maternally acquired Abs against malaria parasite proteins. Many malaria vaccines in development rely upon CD8 cells as immune effectors. Some studies indicate that neonates do not mount optimal CD8 cell responses. We report that BALB/c mice first immunized as neonates (7 days) with a Plasmodium yoelii circumsporozoite protein (PyCSP) DNA vaccine mixed with a plasmid expressing murine GM-CSF (DG) and boosted at 28 days with poxvirus expressing PyCSP were protected (93%) as well as mice immunized entirely as adults (70%). Protection was dependent on CD8 cells, and mice had excellent anti-PyCSP IFN-γ and cytotoxic T lymphocyte responses. Mice born of mothers previously exposed to P. yoelii parasites or immunized with the vaccine were protected and had excellent T cell responses. These data support assessment of this immunization strategy in neonates/young infants in areas in which malaria exacts its greatest toll.
Subcellular Localization of Toll-Like Receptor 3 in Human Dendritic Cells
Authors: Matsumoto Misako , Funami Kenji , Tanabe Masako , Oshiumi Hiroyuki , Shingai Masashi , Seto Yoshiyuki , Yamamoto Akitsugu , Seya Tsukasa 
Published: April 2014

Abstract
Toll-like receptor (TLR)3 recognizes dsRNA and transduces signals to activate NF-κB and IFN-β promoter. Type I IFNs (IFN-α/β) function as key cytokines in anti-viral host defense. Human fibroblasts express TLR3 on the cell surface, and anti-TLR3 mAb inhibits dsRNA-induced IFN-β secretion by fibroblasts, suggesting that TLR3 acts on the cell surface to sense viral infection. In this study, we examined the expression and localization of human TLR3 in various DC subsets using anti-TLR3 mAb. In monocyte-derived immature dendritic cells (iDCs), TLR3 predominantly resided inside the cells but not on the cell surface. iDCs produced IL-12p70 and IFN-α and -β in response to poly(I:C). Similar response was observed in iDCs treated with rotavirus-derived dsRNA. These responses could not be blocked by pretreatment of the cells with anti-TLR3 mAb. In CD11c+ blood DCs, cytoplasmic retention of TLR3 was also observed as in monocyte-derived iDCs, again endorsing a different TLR3 distribution profile from fibroblasts. In precursor DC2, however, TLR3 could not be detected inside or outside the cells. Of note, there was a putative centrosomal protein that shared an epitope with TLR3 in myeloid DCs and precursor DC2, but not peripheral blood monocytes. Immunoelectron microscopic analysis revealed that TLR3, when stably expressed in the murine B cell line Ba/F3, was specifically accumulated in multivesicular bodies, a subcellular compartment situated in endocytic trafficking pathways. Thus, regulation and localization of TLR3 are different in each cell type, which may reflect participation of cell type-specific multiple pathways in antiviral IFN induction via TLR3.
HLA Class II-Restricted CD4+ T Cell Responses Directed Against Influenza Viral Antigens Postinfluenza Vaccination
Authors: Danke Nancy A. , Kwok William W. 
Published: April 2014

Abstract
The memory T cell response is polyclonal, with the magnitude and specificity of the response controlled in part by the burst size of T cells expanded from effector/memory precursors. Sensitive assays using HLA class II multimers were used to detect low-frequency Ag-specific T cells directed against influenza viral Ags in subjects immunized with the influenza vaccine. Direct ex vivo tetramer staining of PBMC from five individuals identified frequencies of hemagglutinin (HA) 306–318 tetramer binding CD4+ T cells in the peripheral blood ranging from 1 in 600 to 1 in 30,000 CD4+ T cells. These frequencies were validated by counting CFSElow, tetramer-positive T cells after in vitro expansion. Low frequency of T cells directed to other influenza epitopes, including DRA1*0101/DRB1*0401-restricted matrix protein 60–73, DRA1*0101/DRB1*0101-restricted matrix protein 18–29, DRA1*0101/DRB1*0701-restricted HA 232–244 and DRA1*0101/DRB1*0101-restricted nucleoprotein 206–217 were also determined. T cells which occurred at a frequency as low as 1 in 350,000 could be ascertained by in vitro expansion of precursors. Peripheral HA306–318-responsive T cells expanded 2- to 5-fold following influenza vaccination. Examination of phenotypic markers of the HA306–318-responsive T cells in the peripheral blood indicated that the majority were CD45RA−, CD27+, CD25−, CD28+, and CD62L−, while T cell clones derived from this population were CD45RA−, CD27−, CD25+, CD28+, and CD62L−.
Vγ4+ γδ T Cells Regulate Airway Hyperreactivity to Methacholine in Ovalbumin-Sensitized and Challenged Mice
Authors: Hahn Youn-Soo , Taube Christian , Jin Niyun , Takeda Katsuyuki , Park Jung-Won , Wands J. M. , Aydintug M. Kemal , Roark Christina L. , Lahn Michael , O’Brien Rebecca L. , Gelfand Erwin W. , Born Willi K. 
Published: April 2014

Abstract
The Vγ4+ pulmonary subset of γδ T cells regulates innate airway responsiveness in the absence of αβ T cells. We now have examined the same subset in a model of allergic airway disease, OVA-sensitized and challenged mice that exhibit Th2 responses, pulmonary inflammation, and airway hyperreactivity (AHR). In sensitized mice, Vγ4+ cells preferentially increased in number following airway challenge. Depletion of Vγ4+ cells before the challenge substantially increased AHR in these mice, but had no effect on airway responsiveness in normal, nonchallenged mice. Depletion of Vγ1+ cells had no effect on AHR, and depletion of all TCR-δ+ cells was no more effective than depletion of Vγ4+ cells alone. Adoptively transferred pulmonary lymphocytes containing Vγ4+ cells inhibited AHR, but lost this ability when Vγ4+ cells were depleted, indicating that these cells actively suppress AHR. Eosinophilic infiltration of the lung and airways, or goblet cell hyperplasia, was not affected by depletion of Vγ4+ cells, although cytokine-producing αβ T cells in the lung increased. These findings establish Vγ4+ γδ T cells as negative regulators of AHR and show that their regulatory effect bypasses much of the allergic inflammatory response coincident with AHR.
Identification of Tissue Transglutaminase as a Novel Molecule Involved In Human CD8+ T Cell Transendothelial Migration
Authors: Mohan Karkada , Pinto Devanand , Issekutz Thomas B. 
Published: April 2014

Abstract
During inflammation, T lymphocytes migrate out of the blood across the vascular endothelium in a multistep process. The receptors mediating T cell adhesion to endothelium are well characterized; however, the molecules involved in T cell transendothelial migration (TEM) subsequent to lymphocyte adhesion to the endothelium are less clear. To identify receptors mediating TEM, mAbs were produced against human blood T cells adhering to IFN-γ-activated HUVEC in mice and tested for inhibition of lymphocyte TEM across cytokine-activated HUVEC. Most of the mAbs were against β1 and β2 integrins, but one mAb, 6B9, significantly inhibited T cell TEM across IFN-γ, TNF-α, and IFN-γ plus TNF-α-stimulated HUVEC, and did not react with an integrin. 6B9 mAb did not inhibit T cell adhesion to HUVEC, suggesting that 6B9 blocked a novel pathway in T cell TEM. The 6B9 Ag was 80 kDa on SDS-PAGE, and was expressed by both blood leukocytes and HUVEC. Immunoaffinity purification and mass spectrometry identified this Ag as tissue transglutaminase (tTG), a molecule not known to mediate T cell TEM. Treatment of HUVEC with 6B9 was more effective than treatment of T cells. 6B9 blockade selectively inhibited CD4−, but not CD4+, T cell TEM, suggesting a role for tTG in recruitment of CD8+ T lymphocytes. Thus, 6B9 is a new blocking mAb to human tTG, which demonstrates that tTG may have a novel role in mediating CD8+ T cell migration across cytokine-activated endothelium and infiltration of tissues during inflammation.
Experimental Evidence for Lack of Homodimerization of the G Protein-Coupled Human N-Formyl Peptide Receptor
Authors: Gripentrog Jeannie M. , Kantele Katrin P. , Jesaitis Algirdas J. , Miettinen Heini M. 
Published: April 2014

Abstract
A large number of G protein-coupled receptors have been shown to form homodimers based on a number of different techniques such as receptor coimmunoprecipitation, cross-linking, and fluorescence resonance energy transfer. In addition, functional assays of cells coexpressing a mutant receptor with a wild-type receptor have shown receptor phenotypes that can best be explained through dimerization. We asked whether the human neutrophil N-formyl peptide receptor (FPR) forms dimers in Chinese hamster ovary cells by coexpressing wild-type FPR with one of two mutants: D71A, which is uncoupled from G protein, and N297A, which has a defect in receptor phosphorylation and endocytosis. Experiments measuring chemotaxis, ligand-induced release of intracellular calcium, and p42/44 mitogen-activated protein kinase activation did not show an inhibitory effect of the coexpressed FPR D71A mutant. Coexpressed wild-type receptor was efficiently internalized, but failed to correct the endocytosis defects of the D71A and the N297A mutants. To explore the possibility that the mutations themselves prevented dimerization, we examined the coimmunoprecipitation of differentially epitope-tagged FPR. Immunoprecipitation of hemagglutinin-tagged FPR failed to coimmunoprecipitate coexpressed c-myc-tagged FPR and vice versa. Together, these data suggest that, unlike many other G protein-coupled receptors, FPR does not form homodimers.
IL-6 Induces NF-κB Activation in the Intestinal Epithelia
Authors: Wang Lixin , Walia Baljit , Evans John , Gewirtz Andrew T. , Merlin Didier , Sitaraman Shanthi V. 
Published: April 2014

Abstract
IL-6 is a potent proinflammatory cytokine that has been shown to play an important role in the pathogenesis of inflammatory bowel disease (IBD). It is classically known to activate gene expression via the STAT-3 pathway. Given the crucial role of IL-6 in the pathogenesis of chronic intestinal inflammation, it is not known whether IL-6 activates NF-κB, a central mediator of intestinal inflammation. The model intestinal epithelial cell line, Caco2-BBE, was used to study IL-6 signaling and to analyze whether suppressor of cytokine signaling 3 (SOCS-3) proteins play a role in the negative regulation of IL-6 signaling. We show that IL-6 receptors are present in intestinal epithelia in a polarized fashion. Basolateral IL-6 and, to a lesser extent, apical IL-6 induces the activation of the NF-κB pathway. Basolateral IL-6 stimulation results in a maximal induction of NF-κB activation and NF-κB nuclear translocation at 2 h. IL-6 induces polarized expression of ICAM-1, an adhesion molecule shown to be important in the neutrophil-epithelial interactions in IBD. Using various deletion constructs of ICAM-1 promoter, we show that ICAM-1 induction by IL-6 requires the activation of NF-κB. We also demonstrate that overexpression of SOCS-3, a protein known to inhibit STAT activation in response to IL-6, down-regulates IL-6-induced NF-κB activation and ICAM-1 expression. In summary, we demonstrate the activation of NF-κB by IL-6 in intestinal epithelia and the down-regulation of NF-κB induction by SOCS-3. These data may have mechanistic and therapeutic implications in diseases such as IBD and rheumatoid arthritis in which IL-6 plays an important role in the pathogenesis.
Soluble IL-6 Receptor Governs IL-6 Activity in Experimental Arthritis: Blockade of Arthritis Severity by Soluble Glycoprotein 130
Authors: Nowell Mari A. , Richards Peter J. , Horiuchi Sankichi , Yamamoto Naoki , Rose-John Stefan , Topley Nicholas , Williams Anwen S. , Jones Simon A. 
Published: April 2014

Abstract
Studies in IL-6-deficient (IL-6−/−) mice highlight that IL-6 contributes to arthritis progression. However, the molecular mechanism controlling its activity in vivo remains unclear. Using an experimental arthritis model in IL-6−/− mice, we have established a critical role for the soluble IL-6R in joint inflammation. Although intra-articular administration of IL-6 itself was insufficient to reconstitute arthritis within these mice, a soluble IL-6R-IL-6 fusion protein (HYPER-IL-6) restored disease activity. Histopathological assessment of joint sections demonstrated that HYPER-IL-6 increased arthritis severity and controlled intrasynovial mononuclear leukocyte recruitment through the CC-chemokine CCL2. Activation of synovial fibroblasts by soluble IL-6R and IL-6 emphasized that these cells may represent the source of CCL2 in vivo. Specific blockade of soluble IL-6R signaling in wild-type mice using soluble gp130 ameliorated disease. Consequently, soluble IL-6R-mediated signaling represents a promising therapeutic target for the treatment of rheumatoid arthritis.
B Cell Deficiency Confers Protection from Renal Ischemia Reperfusion Injury
Authors: Burne-Taney Melissa J. , Ascon Dolores B. , Daniels Frank , Racusen Lorraine , Baldwin William , Rabb Hamid 
Published: April 2014

Abstract
Recent data have demonstrated a role for CD4+ cells in the pathogenesis of renal ischemia reperfusion injury (IRI). Identifying engagement of adaptive immune cells in IRI suggests that the other major cell of the adaptive immune response, B cells, may also mediate renal IRI. An established model of renal IRI was used: 30 min of renal pedicle clamping was followed by reperfusion in B cell-deficient (μMT) and wild-type mice. Renal function was significantly improved in μMT mice compared with wild-type mice at 24, 48, and 72 h postischemia. μMT mice also had significantly reduced tubular injury. Both groups of mice had similar renal phagocyte infiltration postischemia assessed by myeloperoxidase levels and similar levels of CD4+ T cell infiltration postischemia. Peritubular complement C3d staining was also similar in both groups. To identify the contribution of cellular vs soluble mechanism of action, serum transfer into μMT mice partially restored ischemic phenotype, but B cell transfers did not. These data are the first demonstration of a pathogenic role for B cells in ischemic acute renal failure, with a serum factor as a potential underlying mechanism of action.
Lipid Raft Localization of Cell Surface E-Selectin Is Required for Ligation-Induced Activation of Phospholipase Cγ
Authors: Kiely Jeanne-Marie , Hu Yenya , García-Cardeña Guillermo , Gimbrone Michael A. 
Published: April 2014

Abstract
E-selectin, an endothelial cell surface adhesion receptor for leukocytes, also acts as a signaling receptor. Upon multivalent ligation, E-selectin transduces outside-in signals into the endothelium leading to changes in intracellular Ca2+ concentration and activation of the mitogen-activated protein kinase signaling pathway. In addition, following leukocyte engagement, E-selectin associates via its cytoplasmic domain with components of the actin cytoskeleton and undergoes alterations in phosphorylation state that result in changes in gene expression. In this study, we show that E-selectin is localized in cholesterol-rich lipid rafts at the cell surface, and that upon ligation E-selectin clusters and redistributes in the plasma membrane colocalizing with a fraction of caveolin-1-containing rafts. In addition, we demonstrate that leukocyte adhesion via E-selectin results in association with and activation of phospholipase Cγ (PLCγ). Moreover, we show that disruption of lipid rafts with the cholesterol-depleting drug methyl-β-cyclodextrin disrupts the raft localization of E-selectin as well as the ligation-induced association of E-selectin with PLCγ, and subsequent tyrosine phosphorylation of PLCγ. In contrast, cholesterol depletion has no effect on E-selectin-dependent mitogen-activated protein kinase activation. Thus, these findings demonstrate that the presence of E-selectin in lipid rafts is necessary for its association with, and activation of, PLCγ, and suggest that this subcellular localization of E-selectin is related to its signaling function(s) during leukocyte-endothelial interactions.
Hypoxia Inactivates Inducible Nitric Oxide Synthase in Mouse Macrophages by Disrupting Its Interaction with α-Actinin 4
Authors: Daniliuc Sharon , Bitterman Haim , Rahat Michal A. , Kinarty Amalia , Rosenzweig Doron , Nitza Lahat 
Published: April 2014

AbstractNitric oxide, produced in macrophages by the high output isoform inducible NO synthase (iNOS), is associated with cytotoxic effects and modulation of Th1 inflammatory/immune responses. Ischemia and reperfusion lead to generation of high NO levels that contribute to irreversible tissue damage. Ischemia and reperfusion, as well as their in vitro simulation by hypoxia and reoxygenation, induce the expression of iNOS in macrophages. However, the molecular regulation of iNOS expression and activity in hypoxia and reoxygenation has hardly been studied. We show in this study that IFN-γ induced iNOS protein expression (by 50-fold from control, p &lt; 0.01) and nitrite accumulation (71.6 ± 14 μM, p &lt; 0.01 relative to control), and that hypoxia inhibited NO production (7.6 ± 1.7 μM, p &lt; 0.01) without altering iNOS protein expression. Only prolonged reoxygenation restored NO production, thus ruling out the possibility that lack of oxygen, as a substrate, was the cause of hypoxia-induced iNOS inactivation. Hypoxia did not change the ratio between iNOS monomers and dimers, which are essential for iNOS activity, but the dimers were unable to produce NO, despite the exogenous addition of all cofactors and oxygen. Using immunoprecipitation, mass spectroscopy, and confocal microscopy, we demonstrated in normoxia, but not in hypoxia, an interaction between iNOS and α-actinin 4, an adapter protein that anchors enzymes to the actin cytoskeleton. Furthermore, hypoxia caused displacement of iNOS from the submembranal zones. We suggest that the intracellular localization and interactions of iNOS with the cytoskeleton are crucial for its activity, and that hypoxia inactivates iNOS by disrupting these interactions.