bluuebunny/crossref_metadata_2025_split huggingface dataset:
Blocking the Receptor for IL-10 Improves Antimycobacterial Chemotherapy and Vaccination
Authors: Silva Regina A. , Pais Teresa F. , Appelberg Rui 
Published: April 2014

AbstractNovel approaches are required for the prevention and therapy of mycobacterial infections since the only vaccine in use, bacillus Calmette-Guérin, is poorly effective and chemotherapy is long and often ineffective in sterilizing the infection. We used a mouse model of Mycobacterium avium infection to address the usefulness of a mAb able to block IL-10R both in treatment of primary infections and in conventional multidrug therapy and subunit vaccination. Treatment of infected mice with this mAb during the entire period of experimental infection had little impact on the course of M. avium infection, with a slight improvement in the resistance of infected mice observed in the liver and spleen at day 30 of infection, which was associated with increased macrophage activation and priming of CD4+ T cells for IFN-γ production. Administration of this mAb later in infection had no effect on its course, but improved the effectiveness of chemotherapy when the latter was started in a chronic phase of infection. Also, the anti-IL-10R mAb acted as an adjuvant in the induction of protective immunity upon vaccination with a mycobacterial subunit preparation.
Mycobacterium tuberculosis19-kDa Lipoprotein Promotes Neutrophil Activation
Authors: Neufert Clemens , Pai Rish K. , Noss Erika H. , Berger Melvin , Boom W. Henry , Harding Clifford V. 
Published: April 2014

AbstractCertain microbial substances, e.g., LPS, can activate neutrophils or prime them to enhance their response to other activating agents, e.g., fMLP. We investigated the role of the Mycobacterium tuberculosis (MTB) 19-kDa lipoprotein in activation of human neutrophils. MTB 19-kDa lipoprotein initiated phenotypic changes characteristic of neutrophil activation, including down-regulation of CD62 ligand (L-selectin) and up-regulation of CD35 (CR1) and CD11b/CD18 (CR3, Mac-1). In addition, exposure of neutrophils to MTB 19-kDa lipoprotein enhanced the subsequent oxidative burst in response to fMLP as assessed by oxidation of dihydrorhodamine 123 (determined by flow cytometry). LPS also produced these effects with similar kinetics, but an oligodeoxynucleotide containing a CpG motif failed to induce any priming or activation response. Although the effects of LPS required the presence of serum, neutrophil activation by MTB 19-kDa lipoprotein occurred independently of serum factors, suggesting the involvement of different receptors and signaling mechanisms for LPS and MTB 19-kDa lipoprotein. Thus, MTB 19-kDa lipoprotein serves as a pathogen-associated molecular pattern that promotes neutrophil priming and activation.
Complement Is Essential for Protection by an IgM and an IgG3 Monoclonal Antibody Against Experimental, Hematogenously Disseminated Candidiasis
Authors: Han Yongmoon , Kozel Thomas R. , Zhang Mason X. , MacGill Randall S. , Carroll Michael C. , Cutler Jim E. 
Published: April 2014

AbstractThe incidence of life-threatening, hematogenously disseminated candidiasis, which is predominantly caused by Candida albicans, parallels the use of modern medical procedures that adversely affect the immune system. Limited antifungal drug choices and emergence of drug-resistant C. albicans strains indicate the need for novel prevention and therapeutic strategies. We are developing vaccines and Abs that enhance resistance against experimental candidiasis. However, the prevalence of serum anti-Candida Abs in candidiasis patients has led to the misconception that Abs are not protective. To explain the apparent discrepancy between such clinical observations and our work, we compared functional activities of C. albicans-specific protective and nonprotective mAbs. Both kinds of Abs are agglutinins that fix complement and are specific for cell surface mannan, but the protective Abs recognize β-mannan, and the nonprotective Ab is specific for α-mannan. By several indirect and direct measures, the protective mAbs more efficiently bind complement factor C3 to the yeast cell than do nonprotective Ab. We hypothesize that the C3 deposition causes preferential association of blood-borne fungi with host phagocytic cells that are capable of killing the fungus. We conclude from these results that the protective potential of Abs is dependent on epitope specificity, serum titer, and ability to rapidly and efficiently fix complement to the fungal surface. The mechanism of protection appears to be associated with enhanced phagocytosis and killing of the fungus.
DNA Fusion Vaccine Designed to Induce Cytotoxic T Cell Responses Against Defined Peptide Motifs: Implications for Cancer Vaccines
Authors: Rice Jason , Elliott Tim , Buchan Sarah , Stevenson Freda K. 
Published: April 2014

AbstractDNA vaccination offers a strategy to induce immune attack on cancer cells, but tumor Ags are often weak. Inclusion of a “foreign” protein increases immunogenicity, and we found previously that fusion of the fragment C (FrC) of tetanus toxin to the tumor Ag sequence promotes Ab and CD4+ responses against B cell tumors. For CTL responses, use of the full two-domain FrC may be less helpful, because known immunogenic MHC class I-binding peptides in the second domain could compete with attached tumor-derived epitopes. Therefore, we removed the second domain, retaining the N-terminal domain, which contains a “universal” helper epitope. We investigated the ability to induce CTL responses of candidate peptides placed at the C terminus of this domain. As test peptides, we repositioned the two known CTL motifs from the second domain to this site. Strong CTL responses to each peptide were induced by the engineered construct, as compared with the native FrC construct. Induced CTLs were able to specifically kill tumor cells transfected with FrC as a surrogate tumor Ag both in vitro and in vivo. Further reduction of the domain to a short helper epitope generated only weak CTL responses against fused peptides, and synthetic peptides mixed with the plasmid containing the first domain were ineffective. The single FrC domain-peptide vaccine design also was able to induce high levels of CTLs against a known epitope from carcinoembryonic Ag. Response to peptide was suppressed if two FrC domains were present, consistent with immunodominance. These principles and designs may have relevance for cancer vaccines delivered via DNA.
Immunostimulatory DNA-Based Vaccines Elicit Multifaceted Immune Responses Against HIV at Systemic and Mucosal Sites
Authors: Horner Anthony A. , Datta Sandip K. , Takabayashi Kenji , Belyakov Igor M. , Hayashi Tomoko , Cinman Nadya , Nguyen Minh-Duc , Van Uden John H. , Berzofsky Jay A. , Richman Douglas D. , Raz Eyal 
Published: April 2014

AbstractImmunostimulatory DNA sequences (ISS, also known as CpG motifs) are pathogen-associated molecular patterns that are potent stimulators of innate immunity. We tested the ability of ISS to act as an immunostimulatory pathogen-associated molecular pattern in a model HIV vaccine using gp120 envelope protein as the Ag. Mice immunized with gp120 and ISS, or a gp120:ISS conjugate, developed gp120-specific immune responses which included: 1) Ab production; 2) a Th1-biased cytokine response; 3) the secretion of β-chemokines, which are known to inhibit the use of the CCR5 coreceptor by HIV; 4) CTL activity; 5) mucosal immune responses; and 6) CD8 T cell responses that were independent of CD4 T cell help. Based on these results, ISS-based immunization holds promise for the development of an effective preventive and therapeutic HIV vaccine.
CCAAT-Enhancer-Binding Protein β (C/EBPβ) Activates CCR5 Promoter: Increased C/EBPβ and CCR5 in T Lymphocytes from HIV-1-Infected Individuals
Authors: Rosati Margherita , Valentin Antonio , Patenaude Daniel J. , Pavlakis George N. 
Published: April 2014

AbstractC/EBPβ is a member of a family of leucine zipper transcription factors that are involved in regulating the expression of several cytokines, including IL-1, IL-6, IL-8, TNF, and macrophage-inflammatory protein-1α. We identified multiple C/EBPβ binding sites within the gene for CCR5, suggesting that C/EBPβ may be involved in its regulation. Transient transfection experiments in both myeloid and lymphoid cells showed an increase in CCR5 promoter-driven green fluorescent protein production in the presence of C/EBPβ. Deletion analysis identified two C/EBPβ-responsive regions in the CCR5 gene, one in the promoter region and one at the 3′ part of the intron. We provide evidence that, in myeloid cells (U937), C/EBPβ independently activates CCR5 expression through sites located either in the promoter region or in the intron of the CCR5 gene. In contrast, in lymphoid cells (Jurkat) the presence of the intronic cis-regulatory regions is required for C/EBPβ-mediated activation. In agreement with the functional data, EMSA demonstrated that in both myeloid and lymphoid cells C/EBPβ binds specifically to sites present in the intron, whereas interaction with the sites located in the promoter was cell type specific and was detected only in myeloid cells. Analysis of C/EBPβ in primary PBMCs obtained from HIV-1-infected individuals revealed a significant increase in C/EBPβ expression. The enhanced C/EBPβ activity correlated with a higher frequency of circulating CCR5+ lymphocytes in AIDS patients and with a decline in CD4 lymphocyte numbers. Taken together, these results suggest that C/EBPβ is an important regulator of CCR5 expression and may play a relevant role in the pathogenesis of HIV disease.
Extensive Eosinophil Degranulation and Peroxidase-Mediated Oxidation of Airway Proteins Do Not Occur in a Mouse Ovalbumin-Challenge Model of Pulmonary Inflammation
Authors: Denzler Karen L. , Borchers Michael T. , Crosby Jeffrey R. , Cieslewicz Grzegorz , Hines Edith M. , Justice J. Paul , Cormier Stephania A. , Lindenberger Kari A. , Song Wei , Wu Weijia , Hazen Stanley L. , Gleich Gerald J. , Lee James J. , Lee Nancy A. 
Published: April 2014

AbstractParadigms of eosinophil effector function in the lungs of asthma patients invariably depend on activities mediated by cationic proteins released from secondary granules during a process collectively referred to as degranulation. In this study, we generated knockout mice deficient for eosinophil peroxidase (EPO) to assess the role(s) of this abundant secondary granule protein in an OVA-challenge model. The loss of EPO had no effect on the development of OVA-induced pathologies in the mouse. The absence of phenotypic consequences in these knockout animals extended beyond pulmonary histopathologies and airway changes, as EPO-deficient animals also displayed OVA-induced airway hyperresponsiveness after provocation with methacholine. In addition, EPO-mediated oxidative damage of proteins (e.g., bromination of tyrosine residues) recovered in bronchoalveolar lavage from OVA-treated wild-type mice was &lt;10% of the levels observed in bronchoalveolar lavage recovered from asthma patients. These data demonstrate that EPO activities are inconsequential to the development of allergic pulmonary pathologies in the mouse and suggest that degranulation of eosinophils recruited to the lung in this model does not occur at levels comparable to those observed in humans with asthma.
Increased Entry into the IFN-γ Effector Pathway by CD4+ T Cells Selected by I-Ag7 on a Nonobese Diabetic Versus C57BL/6 Genetic Background
Authors: Koarada Syuichi , Wu Yuehong , Ridgway William M. 
Published: April 2014

AbstractIFN-γ-mediated Th1 effects play a major role in the pathogenesis of autoimmune diabetes in nonobese diabetic (NOD) mice. We analyzed functional responses of CD4+ T cells from NOD and B6.G7 MHC congenic mice, which share the H2g7 MHC region but differ in their non-MHC genetic background. T cells from each strain proliferated equally to panstimulation with T cell lectins as well as to stimulation with glutamic acid decarboxylase 524–543 (self) and hen egg lysozyme 11–23 (foreign) I-Ag7-binding peptide epitopes. Despite comparable proliferative responses, NOD CD4+ T cells had significantly increased IFN-γ intracellular/extracellular protein and mRNA responses compared with B6.G7 T cells as measured by intracellular cytokine analysis, time resolved fluorometry, and RNase protection assays. The increased IFN-γ production was not due to an increase in the amount of IFN-γ produced per cell but to an increase in the number of NOD CD4+ T cells entering the IFN-γ-producing pathway. The increased IFN-γ response in NOD mice was not due to increased numbers of activated precursors as measured by activation/memory markers. B6.G7 lymphoid cells demonstrated an absolute decrease in IFN-γ mRNA, an increase in IL-4 mRNA production, and a significantly decreased IFN-γ:IL-4 mRNA transcript ratio compared with NOD cells. CD4+ T cells from C57BL6 mice also showed significantly decreased IFN-γ production compared with CD4+ T cells from NOD.H2b MHC-congenic mice (which have an H2b MHC region introgressed onto an NOD non-MHC background). Therefore, the NOD non-MHC background predisposes to a quantitatively increased IFN-γ response, independent of MHC class II-mediated T cell repertoire selection, even when compared with a prototypical Th1 strain.
Administration of Pentoxifylline During Allergen Sensitization Dissociates Pulmonary Allergic Inflammation from Airway Hyperresponsiveness
Authors: Fleming Carolyn M. , He Hongzhen , Ciota Alex , Perkins David , Finn Patricia W. 
Published: April 2014

AbstractAsthma, a chronic inflammatory disease characterized by intermittent, reversible airflow obstruction and airway hyperresponsiveness (AHR), is classically characterized by an excess of Th2 cytokines (IL-13, IL-4) and depletion of Th1 cytokines (IFN-γ, IL-12). Recent studies indicating an important role for Th1 immunity in the development of AHR with allergic inflammation suggest that Th1/Th2 balance may be important in determining the association of AHR with allergic inflammation. We hypothesized that administration of pentoxifylline (PTX), a phosphodiesterase inhibitor known to inhibit Th1 cytokine production, during allergen (OVA) sensitization and challenge would lead to attenuation of AHR in a murine model of allergic pulmonary inflammation. We found that PTX treatment led to attenuation of AHR when administered at the time of allergen sensitization without affecting other hallmarks of pulmonary allergic inflammation. Attenuation of AHR with PTX treatment was found in the presence of elevated bronchoalveolar lavage fluid levels of the Th2 cytokine IL-13 and decreased levels of the Th1 cytokine IFN-γ. PTX treatment during allergen sensitization leads to a divergence of AHR and pulmonary inflammation following allergen challenge.
Induction of Experimental Autoimmune Thyroiditis in IL-12−/− Mice
Authors: Chen Kemin , Wei Yongzhong , Sharp Gordon C. , Braley-Mullen Helen 
Published: April 2014

AbstractGranulomatous experimental autoimmune thyroiditis (G-EAT) is induced by transfer of mouse thyroglobulin (MTg)-sensitized spleen cells activated in vitro with MTg and anti-IL-2R or MTg and IL-12. Previous work suggested that IL-12 was required in vitro for development of G-EAT. To determine whether IL-12 was also required during the induction and/or effector phases, DBA/1 mice with a disrupted IL-12-P40 gene (IL-12−/−) were used for EAT induction. Cells from MTg-sensitized IL12−/− donors activated in vitro by MTg or MTg and anti-IL2R induced severe EAT in recipient mice. Compared with effector cells from IL-12+/+ donors, effector cells from IL-12−/− donors induced thyroid lesions dominated by lymphocytes with minimal granulomatous changes. Thyroids of recipients of IL-12−/− cells expressed less IFN-γ mRNA and more TGF-β, IL-4, and IL-10 compared with recipients of IL-12+/+ cells. When IL-12 was added during in vitro activation, cells from both IL-12−/− and IL-12+/+ donors induced severe G-EAT, and expression of all cytokines except IL-12 was comparable in thyroids of both IL-12+/+ and IL-12−/− recipients. Transfer of cells from IL-12+/+ or IL-12−/− donors into IL-12+/+ or IL-12−/− recipients indicated that IL-12 expressed in thyroids was derived from recipients. Thus, endogenous IL-12 is not absolutely essential for the sensitization and activation of EAT effector cells to induce severe EAT, although it is required in vitro to promote activation of cells to induce severe granulomatous histopathology.
Allergen-Derived T Cell Peptide-Induced Late Asthmatic Reactions Precede the Induction of Antigen-Specific Hyporesponsiveness in Atopic Allergic Asthmatic Subjects
Authors: Oldfield William L. G. , Kay A. Barry , Larché Mark 
Published: April 2014

Abstract
Allergen-derived peptides can induce T cell tolerance in naive and Ag-primed mice. This is preceded by transient T cell activation. In humans, intradermal administration of short allergen-derived T cell peptide epitopes provokes IgE-independent isolated late asthmatic reactions (LARs) in sensitized subjects. In this study, we determine whether, as in mouse models, such peptides produce hyporesponsiveness to rechallenge with peptides, or whole allergen, either clinically or in terms of in vitro T cell responses. We found that a second injection of cat allergen (Fel d 1)-derived T cell peptides was associated with a marked reduction, or absence, of the LAR, and that up to 40 wk was required for return to baseline values. The cutaneous late-phase reaction to whole cat dander was also inhibited, even in subjects who did not experience an initial LAR. These observations were associated with a significant decrease in peptide- and whole allergen-induced proliferation of PBMCs and the production of IL-4, IL-13, and IFN-γ in cultures. Thus, allergen-derived peptides induce tolerance to subsequent peptide injection in the target organ (the lung), reduce late-phase cutaneous responsiveness to whole allergen, and alter in vitro T cell reactivity.
Short-Term Kinetics of Tumor Antigen Expression in Response to Vaccination
Authors: Ohnmacht Galen A. , Wang Ena , Mocellin Simone , Abati Andrea , Filie Armando , Fetsch Patricia , Riker Adam I. , Kammula Udai S. , Rosenberg Steven A. , Marincola Francesco M. 
Published: April 2014

Abstract
The melanoma patient’s immune response to tumor has been extensively studied. Yet, the frequently observed coexistence of tumor-associated Ag (TAA)-specific T cells with their target cells in vivo remains unexplained. Loss of TAA expression might contribute to this paradox. We studied TAA expression in metastases by obtaining fine-needle aspirations from 52 tumor lesions in 30 patients with melanoma before and soon after immunotherapy. Limitations due to low amounts of starting material were overcome with a high fidelity antisense RNA amplification method. TAA expression was measured by quantitative real-time PCR of anti-sense RNA. Decrease in gp100/Pmel-17 TAA preceded tumor disappearance in several instances and could be best explained by immune selection because most patients had received gp100/Pmel-17-specific vaccination. Conversely, immune selection was absent in nonregressing lesions. These observations suggest that vaccination, when successful, triggers a broad inflammatory reaction that can lead to tumor destruction despite immune selection. Additionally, lack of clinical response might be attributed to lack of this initiating event rather than immune escape. This study provides an insight into the natural history of tumors and defines a strategy for the characterization of gene expression in tumors during therapy.
Intrathecal Delivery of IFN-γ Protects C57BL/6 Mice from Chronic-Progressive Experimental Autoimmune Encephalomyelitis by Increasing Apoptosis of Central Nervous System-Infiltrating Lymphocytes
Authors: Furlan Roberto , Brambilla Elena , Ruffini Francesca , Poliani Pietro L. , Bergami Alessandra , Marconi Peggy C. , Franciotta Diego M. , Penna Giuseppe , Comi Giancarlo , Adorini Luciano , Martino Gianvito 
Published: April 2014

AbstractThe exclusive detrimental role of proinflammatory cytokines in demyelinating diseases of the CNS, such as multiple sclerosis, is controversial. Here we show that the intrathecal delivery of an HSV-1-derived vector engineered with the mouse IFN-γ gene leads to persistent (up to 4 wk) CNS production of IFN-γ and inhibits the course of a chronic-progressive form of experimental autoimmune encephalomyelitis (EAE) induced in C57BL/6 mice by myelin oligodendrocyte glycoprotein (MOG)35–55. Mice treated with the IFN-γ-containing vector before EAE onset showed an earlier onset but a milder course of the disease compared with control mice treated with the empty vector. In addition, 83% of IFN-γ-treated mice completely recovered within 25 days post immunization, whereas control mice did not recover up to 60 days post immunization. Mice treated with the IFN-γ-containing vector within 1 wk after EAE onset partially recovered from the disease within 25 days after vector injection, whereas control mice worsened. Recovery from EAE in mice treated with IFN-γ was associated with a significant increase of CNS-infiltrating lymphocytes undergoing apoptosis. During the recovery phase, the mRNA level of TNFR1 was also significantly increased in CNS-infiltrating cells from IFN-γ-treated mice compared with controls. Our results further challenge the exclusive detrimental role of IFN-γ in the CNS during EAE/multiple sclerosis, and indicate that CNS-confined inflammation may induce protective immunological countermechanisms leading to a faster clearance of encephalitogenic T cells by apoptosis, thus restoring the immune privilege of the CNS.
Cutting Edge: T Cell Migration Regulated by CXCR4 Chemokine Receptor Signaling to ZAP-70 Tyrosine Kinase
Authors: Ottoson Nadine C. , Pribila Jonathan T. , Chan Anissa S. H. , Shimizu Yoji 
Published: April 2014

AbstractChemokines regulate the homeostatic trafficking of lymphocytes and lymphocyte influx into sites of injury and inflammation. The signaling pathways by which chemokine receptors regulate lymphocyte migration remain incompletely characterized. We demonstrate that Jurkat T cells lacking the ZAP-70 tyrosine kinase exhibit reduced migration in response to the CXCR4 ligand CXCL12 when compared with wild-type Jurkat T cells. Expression of wild-type, but not kinase-inactive, ZAP-70 resulted in enhanced migration of ZAP-70-deficient Jurkat T cells. The tyrosine residue at position 292 in the interdomain B region of ZAP-70 exerts a negative regulatory effect on ZAP-70-dependent migration. Stimulation of Jurkat T cells with CXCL12 also resulted in ZAP-70-dependent tyrosine phosphorylation of the Src homology 2 domain-containing leukocyte protein of 76 kDa (SLP-76) adapter protein. Although CXCL12-dependent migration of SLP-76-deficient Jurkat T cells was impaired, re-expression of SLP-76 did not enhance migration. These results suggest a novel function for ZAP-70, but not SLP-76, in CXCR4 chemokine receptor signaling in human T cells.
Cutting Edge: Predominant Expression of a Novel Ikaros Isoform in Normal Human Hemopoiesis
Authors: Payne Kimberly J. , Nicolas Jan-Holly , Zhu Judy Y. , Barsky Lora W. , Crooks Gay M. 
Published: April 2014

AbstractMurine studies implicate Ikaros proteins as regulators of hemopoiesis, particularly in the lymphoid lineages. High homology between murine and human Ikaros suggests that Ikaros expression in the two might be similar. However, initial human studies that focused on leukemia detected novel Ikaros transcripts in patient samples. Thus, novel Ikaros splice forms and DNA nonbinding isoforms were linked with malignancy. We undertook an extensive analysis of normal human Ikaros expression to determine whether novel mRNAs are expressed as proteins and the extent to which these splice variants are unique to leukemia. Here we show that both mRNA and protein for DNA nonbinding Ikaros isoforms and splice variants previously linked to leukemia are expressed in normal human cells. However, our studies identify a new Ikaros isoform not previously described in mouse or human. This isoform is the predominant Ikaros protein in normal human cells, but not in leukemia cell lines.