bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Murine Cytomegalovirus Immunomodulatory Gene m152 Prevents Recognition of Infected Cells by M45-Specific CTL But Does Not Alter the Immunodominance of the M45-Specific CD8 T Cell Response In Vivo
Authors: Gold Marielle C. , Munks Michael W. , Wagner Markus , Koszinowski Ulrich H. , Hill Ann B. , Fling Steven P. 
Published: April 2014

Abstract
Although in vitro studies have shown that herpesviruses, including murine CMV (MCMV), encode genes that interfere with the MHC class I pathway, their effects on the CTL response in vivo is unclear. We identified a Db-restricted CTL epitope from MCMV M45 by screening an MCMV genomic library using CTL clones isolated from mice infected with MCMV lacking m152. Because m152 severely inhibits CTL recognition of M45 in vitro, we questioned whether an M45-specific response would be generated in mice infected with wild-type MCMV expressing m152. Mice infected with wild-type MCMV or MCMVΔm152 made similar responses to the M45 Ag. Moreover, we saw no skewing of the proportion of M45-specific CD8 T cells within the total MCMV-specific response after infection with MCMV with m152. Despite the profound effect m152 has on presentation of M45 in vitro, it does not affect the immunodominance of M45 in the CTL response in vivo.
Modulation of Mac-1 (CD11b/CD18)-Mediated Adhesion by the Leukocyte-Specific Protein 1 Is Key to Its Role in Neutrophil Polarization and Chemotaxis
Authors: Wang Chunjie , Hayashi Hisayoshi , Harrison Rene , Chiu Basil , Chan Jason R. , Ostergaard Hanne L. , Inman Robert D. , Jongstra Jan , Cybulsky Myron I. , Jongstra-Bilen Jenny 
Published: April 2014

Abstract
Leukocyte-specific protein 1 (LSP1) is an intracellular filamentous-actin binding protein which modulates cell motility. The cellular process in which LSP1 functions to regulate motility is not yet identified. In this study, we show that LSP1 negatively regulates fMLP-induced polarization and chemotaxis of neutrophils through its function on adhesion via specific integrins. Using LSP1-deficient (Lsp1−/−) mice, we show increased neutrophil migration into mouse knee joints during zymosan-induced acute inflammation, an inflammatory model in which the number of resident synoviocytes are not affected by LSP1-deficiency. In vitro chemotaxis experiments performed by time-lapse videomicroscopy showed that purified Lsp1−/− bone-marrow neutrophils exhibit an increased migration rate toward a gradient of fMLP as compared with wild-type neutrophils. This difference was observed when cells migrated on fibrinogen, but not fibronectin, suggesting a role for LSP1 in modulating neutrophil adhesion by specific integrins. LSP1 is also a negative regulator of fMLP-induced adhesion to fibrinogen or ICAM-1, but not to ICAM-2, VCAM-1, or fibronectin. These results suggest that LSP1 regulates the function of Mac-1 (CD11b/CD18), which binds only to fibrinogen and ICAM-1 among the substrates we tested. fMLP-induced filamentous actin polarization is also increased in the absence of LSP1 when cells were layered on fibrinogen, but not on fibronectin. Our findings suggest that the increased neutrophil recruitment in Lsp1−/− mice during acute inflammation derives from the negative regulatory role of LSP1 on neutrophil adhesion, polarization, and migration via specific integrins, such as Mac-1, which mediate neutrophil responses to chemotactic stimuli.
Differing Activities of Homeostatic Chemokines CCL19, CCL21, and CXCL12 in Lymphocyte and Dendritic Cell Recruitment and Lymphoid Neogenesis
Authors: Luther Sanjiv A. , Bidgol Afshin , Hargreaves Diana C. , Schmidt Andrea , Xu Ying , Paniyadi Jyothi , Matloubian Mehrdad , Cyster Jason G. 
Published: April 2014

Abstract
Despite their widespread expression, the in vivo recruitment activities of CCL19 (EBV-induced molecule 1 ligand chemokine) and CXCL12 (stromal cell-derived factor 1) have not been established. Furthermore, although CXCL13 (B lymphocyte chemoattractant) has been shown to induce lymphoid neogenesis through induction of lymphotoxin (LT)α1β2, it is unclear whether other homeostatic chemokines have this property. In this work we show that ectopic expression in pancreatic islets of CCL19 leads to small infiltrates composed of lymphocytes and dendritic cells and containing high endothelial venules and stromal cells. Ectopic CXCL12 induced small infiltrates containing few T cells but enriched in dendritic cells, B cells, and plasma cells. Comparison of CCL19 transgenic mice with mice expressing CCL21 (secondary lymphoid tissue chemokine) revealed that CCL21 induced larger and more organized infiltrates. A more significant role for CCL21 is also suggested in lymphoid tissues, as CCL21 protein was found to be present in lymph nodes and spleen at much higher concentrations than CCL19. CCL19 and CCL21 but not CXCL12 induced LTα1β2 expression on naive CD4 T cells, and treatment of CCL21 transgenic mice with LTβR-Fc antagonized development of organized lymphoid structures. LTα1β2 was also induced on naive T cells by the cytokines IL-4 and IL-7. These studies establish that CCL19 and CXCL12 are sufficient to mediate cell recruitment in vivo and they indicate that LTα1β2 may function downstream of CCL21, CCL19, and IL-2 family cytokines in normal and pathological lymphoid tissue development.
IL-15-Dependent Activation-Induced Cell Death-Resistant Th1 Type CD8αβ+NK1.1+ T Cells for the Development of Small Intestinal Inflammation
Authors: Ohta Noriyuki , Hiroi Takachika , Kweon Mi-Na , Kinoshita Naotoshi , Jang Myoung Ho , Mashimo Tadashi , Miyazaki Jun-Ichi , Kiyono Hiroshi 
Published: April 2014

AbstractTo clarify the role of IL-15 at local sites, we engineered a transgenic (Tg) mouse (T3b-IL-15 Tg) to overexpress human IL-15 preferentially in intestinal epithelial cells by the use of T3b-promoter. Although IL-15 was expressed in the entire small intestine (SI) and large intestines of the Tg mice, localized inflammation developed in the proximal SI only. Histopathologic study revealed reduced villus length, marked infiltration of lymphocytes, and vacuolar degeneration of the villus epithelium, beginning at ∼3–4 mo of age. The numbers of CD8+ T cells, especially CD8αβ+ T cells expressing NK1.1, were dramatically increased in the lamina propria of the involved SI. The severity of inflammation corresponded to increased numbers of CD8αβ+NK1.1+ T cells and levels of production of the Th1-type cytokines IFN-γ and TNF-α. Locally overexpressed IL-15 was accompanied by increased resistance of CD8αβ+ NK1.1+ T cells to activation-induced cell death. Our results suggest that chronic inflammation in the SI in this murine model is mediated by dysregulation of epithelial cell-derived IL-15. The model may contribute to understanding the role of CD8+ T cells in human Crohn’s disease involving the SI.
Disruption of a SinglePtenAllele Augments the Chemotactic Response of B Lymphocytes to Stromal Cell-Derived Factor-1
Authors: Fox Joanne A. , Ung Karen , Tanlimco Sonia G. , Jirik Frank R. 
Published: April 2014

AbstractThe tumor suppressor, Pten, has emerged as a critical negative regulator of phosphatidylinositol-3-kinase-dependent intracellular signaling pathways responsible for phenomena such as cellular adhesion, proliferation, and apoptosis. Herein, we present evidence that Pten regulates chemokine-dependent events in B lymphocytes. Primary B cells isolated from Pten+/− mice demonstrated increased responsiveness to stromal cell-derived factor-1-induced chemotaxis. This was accompanied by an elevated level of protein kinase B phosphorylation on Ser473. Our results suggest not only that Pten may be an important regulator of stromal cell-derived factor-1-directed chemotaxis, but also that Pten heterozygosity is associated with increased cellular sensitivity to this chemokine, likely via dysregulation of events lying downstream of phosphatidylinositol-3-kinase. These observations suggest a mechanism by which loss of a single Pten allele may confer a selective advantage on cells during multistep tumor progression.
Inhibition of Endogenous TGF-β During Experimental Osteoarthritis Prevents Osteophyte Formation and Impairs Cartilage Repair
Authors: Scharstuhl Alwin , Glansbeek Harrie L. , van Beuningen Henk M. , Vitters Elly L. , van der Kraan Peter M. , van den Berg Wim B. 
Published: April 2014

Abstract
Osteoarthritis has as main characteristics the degradation of articular cartilage and the formation of new bone at the joint edges, so-called osteophytes. In this study enhanced expression of TGF-β1 and -β3 was detected in developing osteophytes and articular cartilage during murine experimental osteoarthritis. To determine the role of endogenous TGF-β on osteophyte formation and articular cartilage, TGF-β activity was blocked via a scavenging soluble TGF-β-RII. Our results clearly show that inhibition of endogenous TGF-β nearly completely prevented osteophyte formation. In contrast, treatment with recombinant soluble TGF-β-RII markedly enhanced articular cartilage proteoglycan loss and reduced the thickness of articular cartilage. In conclusion, we show for the first time that endogenous TGF-β is a crucial factor in the process of osteophyte formation and has an important function in protection against cartilage loss.
An Autoreactive γδ TCR Derived from a Polymyositis Lesion
Authors: Wiendl Heinz , Malotka Joachim , Holzwarth Brigitte , Weltzien Hans-Ulrich , Wekerle Hartmut , Hohlfeld Reinhard , Dornmair Klaus 
Published: April 2014

Abstract
To investigate the role of γδ T cells in human autoimmune disease we expressed and characterized a γδ TCR from an autoimmune tissue lesion. The TCR was first identified in a rare form of polymyositis characterized by a monoclonal infiltrate of γδ T cells which invaded and destroyed skeletal muscle fibers. The Vγ1.3-Jγ1-Cγ1/Vδ2-Jδ3 TCR cDNA of the original muscle invasive γδ T cell clone was reconstructed from unrelated cDNA and transfected into the mouse hybridoma BW58α−β−. Appropriate anti-human γδ TCR Abs stimulated the TCR transfectants to produce IL-2, thus demonstrating that the human γδ TCR functionally interacted with murine signaling components. The transfected Vγ1.3/Vδ2 TCR recognized a cytosolic protein expressed in cultured human myoblasts and TE671 rhabdomyosarcoma cells. The Ag was recognized in the absence of presenting cells. Using a panel of control γδ TCR transfectants with defined exchanges in different positions of both TCR chains, we showed that the γδ TCR recognized its Ag in a TCR complementarity-determining region 3-dependent way. To our knowledge, this is the first example of a molecularly defined γδ TCR directly derived from an autoimmune tissue lesion. The strategy used in this study may be applicable to other autoimmune diseases.
Antimelanoma Activity of CTL Generated from Peripheral Blood Mononuclear Cells After Stimulation with Autologous Dendritic Cells Pulsed with Melanoma gp100 Peptide G209-2M Is Correlated to TCR Avidity
Authors: Yang Sixun , Linette Gerald P. , Longerich Simonne , Haluska Frank G. 
Published: April 2014

Abstract
Anchor residue-modified peptides derived from tumor-associated Ag have demonstrated success in engendering immune responses in clinical studies. However, tumor regression does not always correlate with immune responses. One hypothesis to explain this is that CTL resulting from such immunization approaches are variable in antitumor potency. In the present study, we evaluated this hypothesis by characterizing the activity of tumor-associated Ag-specific CTL. We chose an anchor residue-modified peptide from gp100, G209-2M, and used peptide-pulsed dendritic cells to generate CTL from PBMC of HLA-A2+ normal donors. The specificities and avidities of the resulting CTL were evaluated. The results demonstrate that CTL generated by G209-2M can be classified into three categories: G209-2M-specific CTL which are cytotoxic only to G209-2M-pulsed targets; peptide-specific CTL which recognize both G209 and G209-2M peptides but not melanomas; and melanoma-reactive CTL which recognize peptide-pulsed targets as well as HLA-A2+gp100+ melanomas. CTL that kill only peptide-pulsed targets require a higher peptide concentration to mediate target lysis, whereas CTL that lyse melanomas need a lower peptide concentration. Increasing peptide density on melanomas by loading exogenous G209 peptide enhances their sensitivity to peptide-specific CTL. High avidity CTL clones also demonstrate potent antimelanoma activity in melanoma model in nude mice. Injection of G209 peptide around transplanted tumors significantly enhances the antitumor activity of low avidity CTL. These results suggest that peptide stimulation causes expansion of T cell populations with a range of avidities. Successful immunotherapy may require selective expansion of the higher-avidity CTL and intratumor injection of the peptide may enhance the effect of peptide vaccines.
Differential Induction of Mucosal and Systemic Antibody Responses in Women After Nasal, Rectal, or Vaginal Immunization: Influence of the Menstrual Cycle
Authors: Kozlowski Pamela A. , Williams Selvi B. , Lynch Rebecca M. , Flanigan Timothy P. , Patterson Rosalyn R. , Cu-Uvin Susan , Neutra Marian R. 
Published: April 2014

Abstract
A cholera vaccine containing killed vibrios and cholera toxin B subunit (CTB) was used to compare mucosal immunization routes for induction of systemic and mucosal Ab. Four groups of women were given three monthly immunizations by the rectal immunization (Rimm) route, nasal immunization (Nimm) route, or vaginal immunization route during either the follicular (V-FPimm) or luteal (V-LPimm) menstrual cycle phase. Nimm was performed with 10-fold less vaccine to determine if administration of less Ag by this route can, as in rodents, produce mucosal Ab responses comparable to those induced by higher dose Rimm or vaginal immunization. Concentrations of Ab induced in sera and secretions were measured by ELISA. None of these routes produced durable salivary Ab responses. Nimm induced greatest levels of CTB-specific IgG in sera. Rimm failed to generate CTB-specific IgA in genital tract secretions. Nimm, V-FPimm, and V-LPimm all produced cervical CTB-specific IgA responses comparable in magnitude and frequency. However, only V-FPimm induced cervical IgA2-restricted Ab to the bacterial LPS vaccine component. V-FPimm, but not V-LPimm, also induced CTB-specific IgA in rectal secretions. Nimm was superior to V-FPimm for producing rectal CTB-specific IgA, but the greatest amounts of CTB-specific IgA and LPS-specific IgA, IgG, and IgM Ab were found in rectal secretions of Rimm women. These data suggest that in women, Nimm alone could induce specific Ab in serum, the genital tract, and rectum. However, induction of genital tract and rectal Ab responses of the magnitude generated by local V-FPimm or Rimm will likely require administration of comparably high nasal vaccine dosages.
Induction of Autoantibody Production Is Limited in Nonautoimmune Mice
Authors: Singh Ram Raj , Ebling Fanny M. , Albuquerque D. Alves , Saxena Vijay , Kumar Vipin , Giannini Edward H. , Marion Tony N. , Finkelman Fred D. , Hahn Bevra H. 
Published: April 2014

Abstract
Many individuals develop a single or a few brief episodes of autoimmunity from which they recover. Mechanisms that quell pathologic autoimmunity following such a breakdown of self-tolerance are not clearly understood. In this study, we show that in nonautoimmune mice, dsDNA-specific autoreactive B cells exist but remain inactive. This state of inactivation in dsDNA-specific B cells could be disrupted by autoreactive Th cells; in this case T cells that react with peptides from the VH region of anti-DNA Abs (hereafter called anti-VH T cells). Immunization with anti-DNA mAb, its γ-chain or peptides derived from its VH region induced anti-VH Th cells, IgG anti-dsDNA Ab, and proteinuria. The breakdown of B cell tolerance in nonautoimmune mice, however, was short-lived: anti-DNA Ab and nephritis subsided despite subsequent immunizations. The recovery from autoimmunity temporally correlated with the appearance of T cells that inhibited anti-DNA Ab production. Such inhibitory T cells secreted TGFβ; the inhibition of anti-DNA Ab production by these cells was partly abolished by anti-TGFβ Ab. Even without immunization, nonautoimmune mice possess T cells that can inhibit autoantibody production. Thus, inhibitory T cells in nonautoimmune mice may normally inhibit T-dependent activation of autoreactive B cells and/or reverse such activation following stimulation by Th cells. The induction of such inhibitory T cells may play a role in protecting nonautoimmune mice from developing chronic autoimmunity.
CD123bright Plasmacytoid Predendritic Cells: Progenitors Undergoing Cell Fate Conversion?
Authors: Comeau Michael R. , Van der Vuurst de Vries Anne-Renee , Maliszewski Charles R. , Galibert Laurent 
Published: April 2014

AbstractCD123bright plasmacytoid cells (PC) and CD1c+ peripheral blood myeloid dendritic cells (DC) are two human DC precursors that can be expanded in vivo by Fms-like tyrosine kinase 3 ligand (FL). It has been proposed that PC and myeloid CD1c+ DC may represent two distinct lineages of DC. However, the phylogenetic affiliation of PC and its relationship with myeloid DC remain controversial. Here we show that CD123brightHLA-DR+ PC from FL-treated healthy volunteers can be divided into mutually exclusive subsets that harbor either lymphoid or myeloid features. Lymphoid-like PC represent the majority of PC and include pTα-, CD3ε-, and CD7-expressing cells. They exhibit TCR-β gene loci in germline configuration and show low allostimulatory capacity, but produce type I IFN upon virus infection and can be differentiated in vitro into potent APC. Myeloid-like PC represent a minor fraction of the total PC population. They exhibit a striking PC/myeloid DC intermediate phenotype (CD5+CD11clowCD45RAlowCD45RO−CD101+), produce proinflammatory cytokines, and do not require in vitro maturation to act as potent APCs. We propose that, rather than forming a lineage, PC might represent a population of lymphoid cells undergoing an in vivo cell fate conversion from a lymphoid to a myeloid cell type.
Cutting Edge: Fever-Associated Temperatures Enhance Neutrophil Responses to Lipopolysaccharide: A Potential Mechanism Involving Cell Metabolism
Authors: Rosenspire Allen J. , Kindzelskii Andrei L. , Petty Howard R. 
Published: April 2014

AbstractAlthough much progress has been made in elucidating the mechanisms underlying the physiological regulation of fever, there is little understanding of the biological utility of fever’s thermal component. Considering the evolutionary co-conservation of fever and innate immunity, we hypothesize that fever’s thermal component might in general augment innate immune function and, in particular, neutrophil activation. Accordingly, we have evaluated the effect of febrile temperatures on neutrophil function at the single-cell level. We find that reactive oxygen intermediates and NO release are greatly enhanced at febrile temperatures for unstimulated as well as LPS-stimulated adherent human neutrophils. Furthermore, our studies suggest that these changes in oxidant release are linked to upstream changes in NADPH dynamics. Inasmuch as reactive oxygen intermediates and NO production are important elements in innate immune responses to bacterial pathogens, we suggest that the febrile rise in core temperature is a broad-based systemic signaling mechanism to enhance innate immunity.
Sonic Hedgehog Signaling Modulates Activation of and Cytokine Production by Human Peripheral CD4+ T Cells
Authors: Stewart Gareth A. , Lowrey Jacqueline A. , Wakelin Sonia J. , Fitch Paul M. , Lindey Susannah , Dallman Margaret J. , Lamb Jonathan R. , Howie Sarah E. M. 
Published: April 2014

Abstract
Sonic hedgehog (Shh) is important in the growth and differentiation of a variety of cell types, including the development of T cells in the thymus. This prompted us to investigate whether Shh signaling is a functional component of the physiological response of human mature CD4+ T cells following Ag recognition. In this study, we demonstrate that Shh and its receptor Patched (Ptc) are expressed on resting and activated human peripheral CD4+ T cells. In approximately one-half of the randomly selected, anonymous blood donors tested, exposure of anti-CD3/28 Ab-activated CD4+ T cells to the biologically active N-terminal Shh peptide increased the transcription of ptc, thereby demonstrating that Shh signaling had occurred. Furthermore, the addition of exogenous Shh amplified the production of IL-2, IFN-γ, and IL-10 by activated CD4+ T cells. The synthesis of IL-2 and IFN-γ, but not IL-10, by CD4+ T cells was down-regulated by the addition of neutralizing anti-Shh Ab. Cell surface expression of CD25 and CD69 on activated T cells was up-regulated by exogenous Shh, whereas in the presence of the neutralizing anti-Shh Ab expression it was reduced. Collectively, our findings demonstrate that Shh-mediated signaling is a physiological component of T cell responses, which acts to modulate CD4+ T cell effector function.
Antigen-Nonspecific Recruitment of Th2 Cells to the Lung as a Mechanism for Viral Infection-Induced Allergic Asthma
Authors: Stephens Robin , Randolph David A. , Huang Guangming , Holtzman Michael J. , Chaplin David D. 
Published: April 2014

AbstractRespiratory viral infections have been shown to trigger exacerbations of asthma; however, the mechanism by which viral Th1-type inflammation exacerbates an allergic Th2-type disease remains unclear. We have previously shown that although adoptively transferred Th2 cells are inefficiently recruited to the lung in response to Ag, cotransfer of Th1 cells can increase accumulation of Th2 cells. In this study, we show that respiratory viral infection increases recruitment of resting Th2 cells specific for OVA even in the absence of OVA challenge. These findings suggest that the mechanism by which Th1-type inflammation enhances allergy is via an effect on recruitment. To study the role of the antigenic specificity of Th1 cells in the enhancement of Th2 cell recruitment and to determine whether virus-induced recruitment of OVA-specific Th2 cells may involve Th1 cells specific to a different Ag, we tested whether hen egg lysozyme-specific Th1 cells could synergize with OVA-specific Th2 cells. Challenge of mice that had received adoptively transferred Th1 cells plus Th2 cells induced the expression of inflammatory chemokines in the lung and increased both recruitment and activation of Th2 cells, leading to eosinophil recruitment, even in the absence of challenge with the Th2 Ag. Interestingly, as IL-5 supports eosinophilia, culture of resting Th2 cells with fresh APC induced production of IL-5 in the absence of specific Ag. Thus, Ag-specific activation of Th1 cells enhances the recruitment potential of the lung leading to recruitment and activation of Th2 cells. This implies that circulating Th2 cells in allergic individuals could enter the lungs in response to infection or inflammation and become activated to trigger allergy.