bluuebunny/crossref_metadata_2025_split huggingface dataset:
Adenosine Augments IL-10 Production by Macrophages through an A2B Receptor-Mediated Posttranscriptional Mechanism
Authors: Németh Zoltán H. , Lutz Carol S. , Csóka Balázs , Deitch Edwin A. , Leibovich S. Joseph , Gause William C. , Tone Masahide , Pacher Pál , Vizi E. Sylvester , Haskó György 
Published: April 2014

Abstract
Adenosine receptor ligands have anti-inflammatory effects and modulate immune responses by up-regulating IL-10 production by immunostimulated macrophages. The adenosine receptor family comprises G protein-coupled heptahelical transmembrane receptors classified into four types: A1, A2A, A2B, and A3. Our understanding of the signaling mechanisms leading to enhanced IL-10 production following adenosine receptor occupancy on macrophages is limited. In this study, we demonstrate that adenosine receptor occupancy increases IL-10 production by LPS-stimulated macrophages without affecting IL-10 promoter activity and IL-10 mRNA levels, indicating a posttranscriptional mechanism. Transfection experiments with reporter constructs containing sequences corresponding to the AU-rich 3′-untranslated region (UTR) of IL-10 mRNA confirmed that adenosine receptor activation acts by relieving the translational repressive effect of the IL-10 3′-UTR. By contrast, adenosine receptor activation failed to liberate the translational arrest conferred by the 3′-UTR of TNF-α mRNA. The IL-10 3′-UTR formed specific complexes with proteins present in cytoplasmic extracts of RAW 264.7 cells. Adenosine enhanced binding of proteins to a region of the IL-10 3′-UTR containing the GUAUUUAUU nonamer. The stimulatory effect of adenosine on IL-10 production was mediated through the A2B receptor, because the order of potency of selective agonists was 5′-N-ethylcarboxamidoadenosine (NECA) &gt; N6-(3-iodobenzyl)-adenosine-5′-N-methyluronamide (IB-MECA) &gt; 2-chloro-N6-cyclopentyladenosine (CCPA) = 2-p-(2-carboxyethyl)phenethylamino-5′-N-ethyl-carboxamidoadenosine (CGS-21680). Also, the selective A2B antagonist, alloxazine, prevented the effect of adenosine. Collectively, these studies identify a novel pathway in which activation of a G protein-coupled receptor augments translation of an anti-inflammatory gene.
Differential Expression of Alternatively Spliced Transcripts of HLA-G in Human Preimplantation Embryos and Inner Cell Masses
Authors: Yao Yuan Q. , Barlow David H. , Sargent Ian L. 
Published: April 2014

Abstract
It has been reported that preimplantation human embryos secrete HLA-G, and the levels may be predictive of their ability to implant. However, it is not known which of the membrane-bound (HLA-G 1–4) and soluble (HLA-G 5–6) alternatively spliced forms are present, nor the developmental stage at which they appear. Therefore, we have investigated HLA-G mRNA isoform expression on single embryos at the two-, four-, six-, and eight-cell, morula, and blastocyst stages. The percentage of embryos expressing each HLA-G isoform mRNA increased with developmental stage, but contrary to expectation, HLA-G5 mRNA was not detected in single two- to eight-cell embryos and was only expressed by 20% of morulae and blastocysts. Similarly, soluble HLA-G6 mRNA was not detected until the blastocyst stage and then in only one-third of embryos. In contrast, labeling with MEM G/9 Ab (specific for HLA-G1 and -G5) was observed in 15 of 20 two- to eight-cell embryos and 5 of 5 blastocysts. This disparity between mRNA and protein may be due to HLA-G protein remaining from maternal oocyte stores produced before embryonic genome activation and brings into question the measurement of soluble HLA-G for clinical evaluation of embryo quality. Although HLA-G is expressed in the preimplantation embryo, later it is primarily expressed in the invasive trophoblast of the placenta rather than the fetus. Therefore, we have investigated whether down-regulation of HLA-G first occurs in the inner cell mass (precursor fetal cells) of the blastocyst and, in support of this concept, have shown the absence HLA-G1 and -G5 protein and mRNA.
Cloning the Arterial IgA Antibody Response during Acute Kawasaki Disease
Authors: Rowley Anne H. , Shulman Stanford T. , Garcia Francesca L. , Guzman-Cottrill Judith A. , Miura Masaru , Lee Hannah L. , Baker Susan C. 
Published: April 2014

AbstractKawasaki disease (KD) is the most common acquired cardiac disease in children in developed nations. The etiology of KD is unknown but likely to be a ubiquitous microbial agent. Previously, we showed that oligoclonal IgA plasma cells infiltrate coronary arteries and other inflamed tissues in acute KD. We demonstrated that a synthetic Ab made using an α H chain sequence prevalent in acute KD arterial tissue detected Ag in acute KD coronary arteries, lung, and other inflamed tissues and that Ag localized to cytoplasmic inclusion bodies in the acute KD ciliated bronchial epithelium. In this study, we synthesized a panel of mAbs from α and κ chain sequences present in the KD arterial wall and tested the Abs for binding to acute KD tissues. We report that all of the synthetic mAbs that bind to acute KD tissues detect Ag in cytoplasmic inclusion bodies in the acute KD ciliated bronchial epithelium. Abs made from α sequences that were prevalent in KD arterial tissue show stronger binding to acute KD tissues than Abs made from less prevalent sequences. These findings highlight the likely importance of the inclusion bodies in the etiopathogenesis of acute KD, confirm that the IgA Ab response in acute KD is Ag driven, and demonstrate the usefulness of cloning the Ab response in diseased tissues to identify disease-relevant Ags.
Global Natural Regulatory T Cell Depletion in Active Systemic Lupus Erythematosus
Authors: Miyara Makoto , Amoura Zahir , Parizot Christophe , Badoual Cécile , Dorgham Karim , Trad Salim , Nochy Dominique , Debré Patrice , Piette Jean-Charles , Gorochov Guy 
Published: April 2014

Abstract
The immune defect that could account for the multisystemic involvement that characterizes systemic lupus erythematosus (SLE) remains unknown. We hypothesized that iterative disease flares correspond to a recurrent defect in the peripheral immune suppression exerted by naturally occurring T regulatory cells (Tregs). Surprisingly, Tregs isolated from lupus patients show the same phenotypic and functional characteristics as corresponding cells found in healthy controls. A decrease in the proportion of circulating Tregs among other CD4+ T cells is nevertheless evidenced in active patients when this group is compared with healthy controls (0.57 ± 0.24%, n = 45 vs 1.29 ± 0.38%, n = 82, p &lt; 0.0001) or with inactive patients (1.22 ± 0.67%, n = 62, p &lt; 0.0001). In contrast, the proportion of Tregs in other systemic autoimmune diseases such as primary Sjögren syndrome and inflammatory myopathy does not significantly differ from controls’ values (1.15 ± 0.46%, n = 21, p = 0.09 and 1.16 ± 0.44%, n = 16, p = 0.43, respectively). Lupus Tregs do not accumulate in either the lymph nodes or the diseased kidneys and are not killed by a circulating soluble factor, but demonstrate in vitro a heightened sensitivity to Fas-induced apoptosis. Finally, we show that the extent of Treg depletion correlates with the clinical severity of the flare. SLE flares are therefore associated with a global Treg depletion and not with a phenomenon of tissue redistribution. In summary, we suggest that the physiopathology of SLE could be tied to a defect in the homeostatic control of the Treg subpopulation.
Immunization with Short Peptides from the 60-kDa Ro Antigen Recapitulates the Serological and Pathological Findings as well as the Salivary Gland Dysfunction of Sjögren’s Syndrome
Authors: Scofield R. Hal , Asfa Sima , Obeso David , Jonsson Roland , Kurien Biji T. 
Published: April 2014

Abstract
Sjögren’s syndrome is a poorly understood autoimmune inflammatory illness that affects the salivary and lacrimal glands as well as other organ systems. We undertook the present study to determine whether mice immunized with short peptides from the 60-kDa Ro (or SSA) Ag, which is a common target of the autoimmunity of Sjögren’s syndrome, develop an illness similar to Sjögren’s syndrome. BALB/c mice were immunized with one of two short peptides from 60-kDa Ro that are know to induce epitope spreading. The animals were analyzed for the presence of anti-Ro and anti-La (or SSB) in the sera by immunoblot and ELISA. Salivary glands were collected and examined by histology after H&E staining. Salivary lymphocytes were purified and studied for cell surface makers by fluorescence-activated cell sorting. Timed stimulated salivary flow was measured. As reported previously, BALB/c mice immunized with 60-kDa Ro peptides developed an immune response directed against the entire Ro/La ribonucleoprotein particle that was similar to that found in humans with lupus or Sjögren’s syndrome. Functional studies showed a statistical decrease in salivary flow in immunized mice compared with controls. Furthermore, there were lymphocytic infiltrates in the salivary glands of immunized animals that were not present in controls. The infiltrates consisted of both CD4− and CD8+ T lymphocytes as well as B lymphocytes. BALB/c mice immunized with 60-kDa Ro peptides develop anti-Ro, salivary gland lymphocyte infiltrates, and salivary dysfunction that is highly reminiscent of human Sjögren’s syndrome.
Physiological Role of Macrophage Inflammatory Protein-3α Induction during Maturation of Intestinal Macrophages
Authors: Hausmann Martin , Bataille Frauke , Spoettl Tanja , Schreiter Katja , Falk Werner , Schoelmerich Juergen , Herfarth Hans , Rogler Gerhard 
Published: April 2014

Abstract
Intestinal macrophages (IMAC) are a central component in the defense of the intestinal mucosa against luminal microbes. In normal mucosa, monocytes differentiate to immunologically tolerant IMAC with a typical phenotype lacking activation markers such as CD14 and TLRs 2 and 4. CD33+ IMAC were isolated from normal intestinal mucosa by immunomagnetic beads. A subtractive hybridization subtracting mRNA from normal IMAC from those of in vitro differentiated macrophages was performed. IMAC differentiation was studied in multicellular spheroids (MCS). Functional assays on migration of CD45R0+ T cells were performed in MCS coculture models. Of 76 clones, 3 obtained by subtractive mRNA hybridization showed &gt;99% homology to mRNA of MIP-3α, indicating that this chemokine is induced in IMAC compared with in vitro differentiated macrophages. MIP-3α protein expression was confirmed in cryostat sections of normal intestinal mucosa by immunohistochemistry. IMAC in the lamina propria stained positive for MIP-3α. FACS of purified IMAC clearly indicated expression of MIP-3α in these cells. In the MCS-in vitro differentiation model for IMAC, MIP-3α protein expression was absent on day 1 but detectable on day 7 of coculture, demonstrating the induction of MIP-3α during differentiation of IMAC. IMAC attracted CD45R0+ T cells to migrate into an MCS coculture model. In human mucosa, a close contact between IMAC and CD45R0+ T cells could be demonstrated. MIP-3α is induced during the differentiation of monocytes into IMAC. Our data suggest that MIP-3α expression could be involved in the recruitment of CD45R0+ cells into the lamina propria.
The Colony-Stimulating Factor 1 Receptor Is Expressed on Dendritic Cells during Differentiation and Regulates Their Expansion
Authors: MacDonald Kelli P. A. , Rowe Vanessa , Bofinger Helen M. , Thomas Ranjeny , Sasmono Tedjo , Hume David A. , Hill Geoffrey R. 
Published: April 2014

Abstract
The lineage of dendritic cells (DC), and in particular their relationship to monocytes and macrophages, remains obscure. Furthermore, the requirement for the macrophage growth factor CSF-1 during DC homeostasis is unclear. Using a transgenic mouse in which the promoter for the CSF-1R (c-fms) directs the expression of enhanced GFP in cells of the myeloid lineage, we determined that although the c-fms promoter is inactive in DC precursors, it is up-regulated in all DC subsets during differentiation. Furthermore, plasmacytoid DC and all CD11chigh DC subsets are reduced by 50–70% in CSF-1-deficient osteopetrotic mice, confirming that CSF-1 signaling is required for the optimal differentiation of DC in vivo. These data provide additional evidence that the majority of tissue DC is of myeloid origin during steady state and supports a close relationship between DC and macrophage biology in vivo.
Tamoxifen Blocks Estrogen-Induced B Cell Maturation but Not Survival
Authors: Peeva Elena , Venkatesh Jeganathan , Diamond Betty 
Published: April 2014

Abstract
Estrogen treatment has been shown not only to exacerbate disease activity and accelerate death in spontaneous murine models of lupus but also to induce a lupus-like phenotype in nonspontaneously autoimmune mice. In mice transgenic for the H chain of an anti-DNA Ab, estrogen rescues naive autoreactive B cells that normally are deleted and causes them to mature to a marginal zone phenotype. Estrogen further leads to the activation of this population causing an elevation of serum anti-DNA Ab titers and renal disease. This study was designed to evaluate the therapeutic potential of tamoxifen, a selective estrogen receptor modulator, on estrogen-induced lupus. Mice treated with both estradiol and tamoxifen showed no elevation in anti-DNA Ab titers and consequently no glomerular IgG. The DNA-reactive B cell population that is rescued by estrogen was present in an anergic state in mice treated with both estradiol and tamoxifen. Estradiol enhances transitional B cell resistance to apoptosis and expands the population of marginal zone B cells; tamoxifen did not impede the enhanced resistance to apoptosis, but prevented the development of autoreactive cells as marginal zone B cells. Thus, estrogen-induced autoimmunity proceeds through two distinct molecular pathways, one affecting survival and the other maturation. Activation, but not survival, of autoreactive B cells can be abrogated by tamoxifen. Drugs that modulate even some of the effects of estrogen may be beneficial in patients with lupus. Eventually, understanding the pathways involved in survival and activation of autoreactive B cells will permit the development of therapeutics that target all relevant pathways.
Dynamic Differentiation of Activated Human Peripheral Blood CD8+ and CD4+ Effector Memory T Cells
Authors: Schwendemann Jochen , Choi Carmen , Schirrmacher Volker , Beckhove Philipp 
Published: April 2014

Abstract
Two functionally different memory T cell subsets were originally defined based on their different CCR7 expression profile, but the lineage relationship between these subsets referred to as central memory T cells (TCM) and effector memory T cells (TEM), is not resolved. A prevalent model proposes a linear progressive differentiation from TCM to TEM. Our results demonstrate that on activation, human CCR7−CD62L− peripheral blood CD8+ and CD4+ TEM cells exhibit a dynamic differentiation, involving transient as well as stable changes to TCM phenotype and properties. Whereas the larger fraction of TEM cells increases expression of effector molecules, such as perforin or IFN-γ, a smaller fraction first acquires CCR7 expression. We demonstrate that this acquisition of lymph node homing potential is associated with strong proliferation similar to that of activated TCM cells. After proliferation, most of these cells lose CCR7 expression again and acquire effector functions (e.g., perforin production). A small proportion (∼6%), however, maintain phenotypic and functional TCM properties over a long time interval. These results suggest that TEM cells provide immediate effector function by a fraction of cells as well as self-renewal by others through up-regulation of CCR7 followed by either secondary peripheral effector function or long term maintenance of TCM-like properties.
Provision of Granulocyte-Macrophage Colony-Stimulating Factor Converts an Autoimmune Response to a Self-Antigen into an Antitumor Response
Authors: Ji Qingyong , Gondek David , Hurwitz Arthur A. 
Published: April 2014

Abstract
Many tumor Ags recognized by T cells are self-Ags. Because high avidity, self-reactive T cells are deleted in the thymus, any residual self-reactive T cells existing in the periphery are likely to be low avidity and nonresponsive due to peripheral tolerance mechanisms. Activation of these residual T cells is critical for targeting tumors for immunotherapy. In this study, we studied immune responses against the murine B16 melanoma using a tyrosinase-related protein 2 (TRP-2) peptide as a model tumor/self-Ag. Our results showed that TRP-2 peptide vaccination alone elicited a weak T cell response and modestly decreased B16 lung tumor nodules. The combination of peptide vaccination and treatment with an Ab directed against the inhibitory receptor CTLA-4 enhanced the immune response against TRP-2 peptide, inducing autoimmune depigmentation and further decreasing lung tumor nodules. However, both vaccination methods failed to protect against orthotopic (s.c.) B16 tumor challenge. The addition of an irradiated GM-CSF-expressing, amelanotic tumor cell vaccine significantly delayed s.c. B16 tumor growth. Subsequent studies revealed that provision of GM-CSF increased dendritic cell numbers in lymph nodes and spleen. Furthermore, addition of CTLA-4 blockade increased the frequency of TRP-2-specific, IFN-secreting T cells in spleen and lymph nodes. Overall, our results indicate that combining enhancement of Ag presentation with removal of CTLA-4-mediated inhibition can convert a “weaker” autoimmune response into a more potent antitumor immune response.
T Cell Tolerance Induced by Cross-Reactive TCR Ligands Can Be Broken by Superagonist Resulting in Anti-Inflammatory T Cell Cytokine Production
Authors: Illés Zsolt , Waldner Hanspeter , Reddy Jayagopala , Bettelli Estelle , Nicholson Lindsay B. , Kuchroo Vijay K. 
Published: April 2014

Abstract
Cross-reactive activation of potentially autoreactive T cells by high-affinity nonself ligands may be important in breaking self-tolerance in autoimmunity. In a mouse transgenic for a cross-reactive TCR, we have previously shown that a hyperstimulating altered peptide ligand, L144, induced unresponsiveness to the self peptide, proteolipid protein 139–151. In this study, we demonstrate that a superagonist ligand can break T cell tolerance induced by the lower affinity cognate Ag. T cells tolerant to the cognate ligand, Q144, responded to superagonist, L144, by proliferation and the production of mainly IL-4 and IL-10 in vitro. In contrast, T cells that were tolerized to the superagonist were unable to respond to any peptide that cross-reacted with the transgenic TCR. Low-dose immunization with the superagonist L144 was able to break tolerance to the cognate ligand in vivo and resulted in a blunted proliferative response with production of Th2 cytokines.
Adenovirus Infection Dramatically Augments Lipopolysaccharide-Induced TNF Production and Sensitizes to Lethal Shock
Authors: Fejér György , Szalay Katalin , Győry Ildikó , Fejes Mária , Kúsz Erzsébet , Nedieanu Saviana , Páli Tibor , Schmidt Tibor , Siklódi Botond , Lázár György , Lázár György , Duda Ernő 
Published: April 2014

Abstract
We observed a remarkable synergism of adenoviruses and LPS in triggering the production of TNF in intact animals. We found that in mice pre-exposed to adenoviruses, LPS injections generated extremely high levels of TNF with altered kinetics. The elevated TNF synthesis stemmed mostly from posttranscriptional up-regulation of TNF production, although transcription of the TNF gene was also induced. Adenoviruses and LPS exhibited a significant but less dramatic synergism in the induction of IL-6, IFN-γ, and NO. Only marginal changes were detected in the synthesis of a panel of other cytokines. Different serotypes of the virus showed practically identical effects. As deletion mutants lacking indispensable viral genes or UV inactivated virions exhibited similar activities as the infectious, wild-type virus, it seems unlikely that the viral genome plays any significant role in the phenomenon. Published data indicate that other viruses also show some kind of synergism with LPS, although by different cellular mechanisms. T cells and their IFN-γ production—crucial in the synergism of influenza viruses and LPS—were dispensable in our experiments. We suggest that the phenomenon is probably a general one: an overlap between different molecular mechanisms detecting bacterial and viral pathogens and inducing mediators of nonspecific cell-mediated host defense. The synergism of viruses and LPS (bacteria) could be a concern in medical practice as well as in gene therapy experiments with high doses of recombinant adenoviruses.
Regulation of Bim by TCR Signals in CD4/CD8 Double-Positive Thymocytes
Authors: Bunin Anna , Khwaja Fatima W. , Kersh Gilbert J. 
Published: April 2014

Abstract
Bim, a BH3-only Bcl-2 family member, is required for apoptosis of thymocytes in response to negative selection signals. Regulation of the apoptotic activity of Bim during negative selection is not understood. In this study we demonstrate that in murine thymocytes undergoing apoptosis in response to anti-CD3ε injection, levels of Bim protein expression do not change. In immature thymocytes, Bim is associated with mitochondria before stimulation and is not regulated by a change in subcellular localization during apoptosis. We also show that BimEL is rapidly phosphorylated in thymocytes in response to CD3ε cross-linking both in vivo and in vitro, and that phosphorylation is sustained for at least 24 h. Analysis of MHC-deficient mice shows that phosphorylation of Bim occurs in CD4/CD8 double-positive thymocytes and does not depend on activation of mature T cells. We also find that TCR cross-linking on thymocytes induces an increase in the proportion of Bcl-xL bound to Bim at late time points. Our results favor a model in which strong TCR signals regulate the apoptotic activity of Bim by phosphorylation and subsequent changes in binding to Bcl-xL in immature thymocytes.
α-Galactosylceramide-Induced Liver Injury in Mice Is Mediated by TNF-α but Independent of Kupffer Cells
Authors: Biburger Markus , Tiegs Gisa 
Published: April 2014

Abstract
NKT cells expressing phenotypic markers of both T and NK cells seem to be pivotal in murine models of immune-mediated liver injury, e.g., in Con A-induced hepatitis. Also α-galactosylceramide (α-GalCer), a specific ligand for invariant Vα14 NKT cells, induces hepatic injury. To improve the comprehension of NKT-cell mediated liver injury, we investigated concomitants and prerequisites of α-GalCer-induced hepatitis in mice. Liver injury induced by α-GalCer injection into C57BL/6 mice was accompanied by intrahepatic caspase-3 activity but appeared independent thereof. α-GalCer injection also induces pronounced cytokine responses, including TNF-α, IFN-γ, IL-2, IL-4, and IL-6. We provide a detailed time course for the expression of these cytokines, both in liver and plasma. Cytokine neutralization revealed that, unlike Con A-induced hepatitis, IFN-γ is not only dispensable for α-GalCer-induced hepatotoxicity but even appears to exert protective effects. In contrast, TNF-α was clearly identified as an important mediator for hepatic injury in this model that increased Fas ligand expression on NKT cells. Whereas intrahepatic Kupffer cells are known as a pivotal source for TNF-α in Con A-induced hepatitis, they were nonessential for α-GalCer-mediated hepatotoxicity. In α-GalCer-treated mice, TNF-α was produced by intrahepatic lymphocytes, in particular NKT cells. BALB/c mice were significantly less susceptible to α-GalCer-induced liver injury than C57BL/6 mice, in particular upon pretreatment with d-galactosamine, a hepatocyte-specific sensitizer to TNF-α-mediated injury. Finally, we demonstrate resemblance of murine α-GalCer-induced hepatitis to human autoimmune-like liver disorders. The particular features of this model compared with other immune-mediated hepatitis models may enhance comprehension of basic mechanisms in the etiopathogenesis of NKT cell-comprising liver disorders.