bluuebunny/crossref_metadata_2025_split huggingface dataset:
Deletion of Secretory Group V Phospholipase A2 Attenuates Cell Migration and Airway Hyperresponsiveness in Immunosensitized Mice
Authors: Muñoz Nilda M. , Meliton Angelo Y. , Arm Jonathan P. , Bonventre Joseph V. , Cho Wonhwa , Leff Alan R. 
Published: April 2014

Abstract
We investigated the role of group V phospholipase A2 (gVPLA2) in OVA-induced inflammatory cell migration and airway hyperresponsiveness (AHR) in C57BL/6 mice. Repeated allergen challenge induced biosynthesis of gVPLA2 in airways. By aerosol, gVPLA2 caused dose-related increase in airway resistance in saline-treated mice; in allergic mice, gVPLA2 caused persistent airway narrowing. Neither group IIa phospholipase A2, a close homolog of gVPLA2, nor W31A, an inactive gVPLA2 mutant with reduced activity, caused airway narrowing in immune-sensitized mice. Pretreatment with MCL-3G1, a blocking Ab against gVPLA2, before OVA challenge blocked fully gVPLA2-induced cell migration and airway narrowing as marked by reduction of migrating leukocytes in bronchoalveolar lavage fluid and decreased airway resistance. We also assessed whether nonspecific AHR caused by methacholine challenge was elicited by gVPLA2 secreted from resident airway cells of immune-sensitized mice. MCL-3G1 also blocked methacholine-induced airway bronchoconstriction in allergic mice. Blockade of bronchoconstriction by MCL-3G1 was replicated in allergic pla2g5−/− mice, which lack the gene encoding gVPLA2. Bronchoconstriction caused by gVPLA2 in pla2g4−/− mice was comparable to that in pla2g4+/+ mice. Our data demonstrate that gVPLA2 is a critical messenger enzyme in the development of AHR and regulation of cell migration during immunosensitization by a pathway that is independent of group IVa phospholipase A2.
A Critical Role for TLR4 in the Pathogenesis of Necrotizing Enterocolitis by Modulating Intestinal Injury and Repair
Authors: Leaphart Cynthia L. , Cavallo Jaime , Gribar Steven C. , Cetin Selma , Li Jun , Branca Maria F. , Dubowski Theresa D. , Sodhi Chhinder P. , Hackam David J. 
Published: April 2014

Abstract
Necrotizing enterocolitis (NEC) is the leading cause of death from gastrointestinal disease in preterm infants and is characterized by translocation of LPS across the inflamed intestine. We hypothesized that the LPS receptor (TLR4) plays a critical role in NEC development, and we sought to determine the mechanisms involved. We now demonstrate that NEC in mice and humans is associated with increased expression of TLR4 in the intestinal mucosa and that physiological stressors associated with NEC development, namely, exposure to LPS and hypoxia, sensitize the murine intestinal epithelium to LPS through up-regulation of TLR4. In support of a critical role for TLR4 in NEC development, TLR4-mutant C3H/HeJ mice were protected from the development of NEC compared with wild-type C3H/HeOUJ littermates. TLR4 activation in vitro led to increased enterocyte apoptosis and reduced enterocyte migration and proliferation, suggesting a role for TLR4 in intestinal repair. In support of this possibility, increased NEC severity in C3H/HeOUJ mice resulted from increased enterocyte apoptosis and reduced enterocyte restitution and proliferation after mucosal injury compared with mutant mice. TLR4 signaling also led to increased serine phosphorylation of intestinal focal adhesion kinase (FAK). Remarkably, TLR4 coimmunoprecipitated with FAK, and small interfering RNA-mediated FAK inhibition restored enterocyte migration after TLR4 activation, demonstrating that the FAK-TLR4 association regulates intestinal healing. These findings demonstrate a critical role for TLR4 in the development of NEC through effects on enterocyte injury and repair, identify a novel TLR4-FAK association in regulating enterocyte migration, and suggest TLR4/FAK as a therapeutic target in this disease.
Generation of Th1 and Th2 Chemokines by Human Eosinophils: Evidence for a Critical Role of TNF-α
Authors: Liu Lin Ying , Bates Mary Ellen , Jarjour Nizar N. , Busse William W. , Bertics Paul J. , Kelly Elizabeth A. B. 
Published: April 2014

Abstract
Emerging evidence suggests a role for eosinophils in immune regulation of T cells. Thus, we sought to determine whether human eosinophils may exert their effect via differential generation of Th1 and Th2 chemokines depending on cytokines in their microenvironment and, if so, to establish the conditions under which these chemokines are produced. Eosinophils cultured with TNF-α plus IL-4 had increased mRNA expression and protein secretion of the Th2-type chemokines, CCL17 (thymus and activation-regulated chemokine) and CCL22 (macrophage-derived chemokine). Conversely, the Th1-type chemokines, CXCL9 (monokine induced by IFN-γ) and CXCL10 (IFN-γ-inducible protein-10), were expressed after stimulation with TNF-α plus IFN-γ. Addition of TNF-α appeared to be essential for IFN-γ-induced release of Th1-type chemokines and significantly enhanced IL-4-induced Th2-type chemokines. Inhibition of NF-κB completely blocked the production of both Th1 and Th2 chemokines. Activation of NF-κB, STAT6, and STAT1 was induced in eosinophils by TNF-α, IL-4, and IFN-γ, respectively. However, there was no evidence for enhancement of these signaling events when eosinophils were stimulated with the combination of TNF-α plus IL-4 or TNF-α plus IFN-γ. Thus, independently activated signaling cascades appear to lead to activation of NF-κB, STAT1, and STAT6, which may then cooperate at the promoter level to increase gene transcription. Our data demonstrate that TNF-α is a vital component for eosinophil chemokine generation and that, depending on the cytokines present in their microenvironment, eosinophils can promote either a Th2 or a Th1 immune response, supporting an immunoregulatory role for eosinophils.
A Novel Inflammatory Pathway Involved in Leukocyte Recruitment: Role for the Kinin B1 Receptor and the Chemokine CXCL5
Authors: Duchene Johan , Lecomte Florence , Ahmed Saleh , Cayla Cecile , Pesquero Joao , Bader Michael , Perretti Mauro , Ahluwalia Amrita 
Published: April 2014

Abstract
The kinin B1 receptor is an inducible receptor not normally expressed but induced by inflammatory stimuli and plays a major role in neutrophil recruitment, particularly in response to the cytokine IL-1β. However, the exact mechanism involved in this response is unclear. The aim of this study was to dissect the molecular mechanism involved, in particular to determine whether specific ELR-CXCL chemokines (specific neutrophil chemoattractants) played a role. Using intravital microscopy, we demonstrated that IL-1β-induced leukocyte rolling, adherence, and emigration in mesenteric venules of wild-type (WT) mice, associated with an increase in B1 receptor mRNA expression, were substantially attenuated (&gt;80%) in B1 receptor knockout mice (B1KO). This effect in B1KO mice was correlated with a selective down-regulation of IL-1β-induced CXCL5 mRNA and protein expression compared with WT mice. Furthermore a selective neutralizing CXCL5 Ab caused profound suppression of leukocyte emigration in IL-1β-treated WT mice. Finally, treatment of human endothelial cells with IL-1β enhanced mRNA expression of the B1 receptor and the human (h) CXCL5 homologues (hCXCL5 and hCXCL6). This response was suppressed by ∼50% when cells were pretreated with the B1 receptor antagonist des-Arg9-[Leu8]-bradykinin while treatment with des-Arg9-bradykinin, the B1 receptor agonist, caused a concentration-dependent increase in hCXCL5 and hCXCL6 mRNA expression. This study unveils a proinflammatory pathway centered on kinin B1 receptor activation of CXCL5 leading to leukocyte trafficking and highlights the B1 receptor as a potential target in the therapeutics of inflammatory disease.
B Cells Amplify IFN-γ Production By T Cells via a TNF-α-Mediated Mechanism
Authors: Menard Laurence C. , Minns Laurie A. , Darche Sylvie , Mielcarz Daniel W. , Foureau David M. , Roos David , Dzierszinski Florence , Kasper Lloyd H. , Buzoni-Gatel Dominique 
Published: April 2014

AbstractAside from being the precursors of the Ab-secreting cells, B cells are engaged in other immune functions such as Ag presentation to T cells or cytokine production. These functions may contribute to the pathogenic role of B cells in a wide range of autoimmune diseases. We demonstrate that B cells acquire the capacity to amplify IFN-γ production by CD4 and CD8 T cells during the course of the Th1 inflammatory response to Toxoplasma gondii infection. Using the two following different strategies, we observed that B cells from T. gondii-infected mice, but not from naive mice, induce higher IFN-γ expression by splenic host T cells: 1) reconstitution of B cell-deficient mice with B cells expressing an alloantigen different from the recipients, and 2) adoptive transfer of B and T cells into RAG−/− mice. In vitro assays allowing the physical separation of T and B cells demonstrate that Ag-primed B cells enhance IFN-γ production by T cells in a contact-dependent fashion. Using an OVA-transgenic strain of T. gondii and OVA-specific CD4 T cells, we observed that the proinflammatory effect of B cells is neither Ag specific nor requires MHCII expression. However, TNF-α expressed on the surface of B cells appears to mediate in part the up-regulation of IFN-γ by the effector T cells.
Deficiency of the NF-κB Inhibitor Caspase Activating and Recruitment Domain 8 in Patients with Rheumatoid Arthritis Is Associated with Disease Severity
Authors: Fontalba Ana , Martinez-Taboada Victor , Gutierrez Olga , Pipaon Carlos , Benito Natividad , Balsa Alejandro , Blanco Ricardo , Fernandez-Luna Jose L. 
Published: April 2014

Abstract
Caspase activating and recruitment domain 8 (CARD8) potently inhibits NF-κB signaling, which plays a key role in inflammation, and may contribute to avoid a pathologic activation of NF-κB; however, the transcriptional mechanisms regulating CARD8 expression and the relevance of this protein in inflammatory diseases are poorly understood. We found a NF-κB-binding element within the human CARD8 promoter that was required for transcriptional activity in response to TNF-α and the p65 subunit of NF-κB. Moreover, TNF-α and overexpression of p65 induced the formation of NF-κB-CARD8 promoter complexes. Thus, CARD8 may control NF-κB activation through a regulatory loop. To study the relevance of CARD8 in chronic inflammatory disorders, we functionally characterized a deleterious polymorphism (p.C10X) and studied its association with rheumatoid arthritis (RA). Transfection of cell lines with the allelic variants of CARD8 revealed that full-length (CARD8-L) but not truncated (CARD8-S) protein inhibits NF-κB transcriptional activity, and abrogates the binding of NF-κB to its consensus site. Furthermore, in contrast to the full-length protein, CARD8-S did not modify the expression of NF-κB target genes (cIAP, A1), in response to TNF-α. We analyzed the p.C10X polymorphism in 200 patients with RA, and found that homozygous carriers of the CARD8-S allele have higher disease activity score (p = 0.014), more extra-articular manifestations (p = 0.03), and a lower probability of clinical remission (p = 0.03) than the CARD8-L allele carriers. Overall, our findings provide molecular insight into the expression of CARD8 by NF-κB, and suggest that a deleterious polymorphism of CARD8 may help predict the severity of RA.
Elf-1 Binds to GGAA Elements on the FcRγ Promoter and Represses Its Expression
Authors: Juang Yuang-Taung , Sumibcay Laarni , Tolnay Mate , Wang Ying , Kyttaris Vasileios C. , Tsokos George C. 
Published: April 2014

Abstract
The Fc receptor (FcR) γ-chain has been shown to be up-regulated in T cells when the TCR ζ-chain is decreased. We demonstrate that Elf-1, but not other Ets family transcription factors, bind to a cluster of GGAA sites located within the 200 bp upstream from the transcription initiation site of the FcRγ promoter. Forced expression of Elf-1 results in the suppression of FcRγ expression, whereas silencing its expression with small interfering RNA Elf-1 results in increased FcRγ expression. Elf-1 represents the first transcription factor identified to be involved in the transcriptional regulation of FcRγ, and cells that fail to express Elf-1, as is the case with human systemic lupus erythematosus T cells, will express FcRγ-chain.
Defective Expression of Ras Guanyl Nucleotide-Releasing Protein 1 in a Subset of Patients with Systemic Lupus Erythematosus
Authors: Yasuda Shinsuke , Stevens Richard L. , Terada Tomoko , Takeda Masumi , Hashimoto Toko , Fukae Jun , Horita Tetsuya , Kataoka Hiroshi , Atsumi Tatsuya , Koike Takao 
Published: April 2014

Abstract
Dysregulation of Ras guanyl nucleotide-releasing protein 1 (RasGRP1) in mice results in a systemic lupus erythematosus (SLE)-like disorder. We therefore looked for defective isoforms and/or diminished levels of human RasGRP1 in a cohort of SLE patients. PBMCs were collected from twenty healthy individuals and thirty-two patients with SLE. mRNA was isolated and five RasGRP1 cDNAs from each subject were sequenced. T cell lysates from healthy controls and SLE patients also were evaluated for their levels of RasGRP1 protein. The accumulated data led to the identification of 13 new splice variants of the human RasGRP1 gene. Not only did our SLE patients have increased levels and types of these defective transcripts relative to normal individuals, two SLE patients were identified whose PBMCs and T cells contained very little, if any, functional RasGRP1 mRNA and protein. The presence of aberrantly spliced RasGRP1 transcripts also was correlated with lower levels of RasGRP1 protein in the patients’ T cells. The lack of the normal isoform of RasGRP1 in some SLE patients and the increased prevalence of defective isoforms of RasGRP1 in others raise the possibility that dysregulation of this signaling protein contributes to the development of autoimmunity in a subset of SLE patients.
Achieving Donor-Specific Hyporesponsiveness Is Associated with FOXP3+ Regulatory T Cell Recruitment in Human Renal Allograft Infiltrates
Authors: Bestard Oriol , Cruzado Josep M. , Mestre Mariona , Caldés Anna , Bas Jordi , Carrera Marta , Torras Joan , Rama Inés , Moreso Francesc , Serón Daniel , Grinyó Josep M. 
Published: April 2014

AbstractExploring new immunosuppressive strategies inducing donor-specific hyporesponsiveness is an important challenge in transplantation. For this purpose, a careful immune monitoring and graft histology assessment is mandatory. Here, we report the results of a pilot study conducted in twenty renal transplant recipients, analyzing the immunomodulatory effects of a protocol based on induction therapy with rabbit anti-thymocyte globulin low doses, sirolimus, and mofetil mycophenolate. Evolution of donor-specific cellular and humoral alloimmune response, peripheral blood lymphocyte subsets and apoptosis was evaluated. Six-month protocol biopsies were performed to assess histological lesions and presence of FOXP3+ regulatory T cells (Tregs) in interstitial infiltrates. After transplantation, there was an early and transient apoptotic effect, mainly within the CD8+HLADR+ T cells, combined with a sustained enhancement of CD4+CD25+high lymphocytes in peripheral blood. The incidence of acute rejection was 35%, all steroid sensitive. Importantly, only pretransplant donor-specific cellular alloreactivity could discriminate patients at risk to develop acute rejection. Two thirds of the patients became donor-specific hyporesponders at 6 and 24 mo, and the achievement of this immunologic state was not abrogated by prior acute rejection episodes. Remarkably, donor-specific hyporesponders had the better renal function and less chronic renal damage. Donor-specific hyporesponsiveness was inhibited by depleting CD4+CD25+high T cells, which showed donor-Ag specificity. FOXP3+CD4+CD25+high Tregs both in peripheral blood and in renal infiltrates were higher in donor-specific hyporesponders than in nonhyporesponders, suggesting that the recruitment of Tregs in the allograft plays an important role for renal acceptance. In conclusion, reaching donor-specific hyporesponsiveness is feasible after renal transplantation and associated with Treg recruitment in the graft.
4-1BB Is Superior to CD28 Costimulation for Generating CD8+ Cytotoxic Lymphocytes for Adoptive Immunotherapy
Authors: Zhang Hua , Snyder Kristen M. , Suhoski Megan M. , Maus Marcela V. , Kapoor Veena , June Carl H. , Mackall Crystal L. 
Published: April 2014

AbstractArtificial APCs (aAPCs) genetically modified to express selective costimulatory molecules provide a reproducible, cost-effective, and convenient method for polyclonal and Ag-specific expansion of human T cells for adoptive immunotherapy. Among the variety of aAPCs that have been studied, acellular beads expressing anti-CD3/anti-CD28 efficiently expand CD4+ cells, but not CD8+ T cells. Cell-based aAPCs can effectively expand cytolytic CD8+ cells, but optimal costimulatory signals have not been defined. 4-1BB, a costimulatory molecule expressed by a minority of resting CD8+ T cells, is transiently up-regulated by all CD8+ T cells following activation. We compared expansion of human cytolytic CD8+ T cells using cell-based aAPCs providing costimulation via 4-1BB vs CD28. Whereas anti-CD3/anti-CD28 aAPCs mostly expand naive cells, anti-CD3/4-1BBL aAPCs preferentially expand memory cells, resulting in superior enrichment of Ag-reactive T cells which recognize previously primed Ags and efficient expansion of electronically sorted CD8+ populations reactive toward viral or self-Ags. Using HLA-A2-Fc fusion proteins linked to 4-1BBL aAPCs, 3-log expansion of Ag-specific CD8+ CTL was induced over 14 days, whereas similar Ag-specific CD8+ T cell expansion did not occur using HLA-A2-Fc/anti-CD28 aAPCs. Furthermore, when compared with cytolytic T cells expanded using CD28 costimulation, CTL expanded using 4-1BB costimulation mediate enhanced cytolytic capacity due, in part, to NKG2D up-regulation. These results demonstrate that 4-1BB costimulation is essential for expanding memory CD8+ T cells ex vivo and is superior to CD28 costimulation for generating Ag-specific products for adoptive cell therapy.
Administration of a CD25-Directed Immunotoxin, LMB-2, to Patients with Metastatic Melanoma Induces a Selective Partial Reduction in Regulatory T Cells In Vivo
Authors: Powell Daniel J. , Felipe-Silva Aloisio , Merino Maria J. , Ahmadzadeh Mojgan , Allen Tamika , Levy Catherine , White Donald E. , Mavroukakis Sharon , Kreitman Robert J. , Rosenberg Steven A. , Pastan Ira 
Published: April 2014

AbstractCD25+CD4+ T regulatory (Treg) cells regulate peripheral self tolerance and possess the ability to suppress antitumor responses, which may in part explain the poor clinical response of cancer patients undergoing active immunization protocols. We have previously shown that in vitro incubation of human PBMC with LMB-2, a CD25-directed immunotoxin, significantly reduced CD25+FOXP3+CD4+ Treg cells without impairing the function of the remaining lymphocytes. In the current study, eight patients with metastatic melanoma were treated with LMB-2 followed by MART-1 and gp100-specific peptide vaccination. LMB-2 administration resulted in a preferential, transient reduction in mean circulating CD25+CD4+ T cell number, from 83 ± 16 cells/μl to a nadir of 17 ± 5 cells/μl, a 79.1% reduction. FOXP3 analysis revealed a less robust depletion with mean FOXP3+CD4+ Treg cell number decreasing from 74 ± 15 cells/μl to 36 ± 8 cells/μl, a 51.4% reduction. FOXP3+CD4+ Treg cells that survived LMB-2-mediated cytotoxicity expressed little or no CD25. Similar to the peripheral blood, immunohistochemical analysis showed a 68.9% mean reduction in FOXP3+CD4+ Treg cell frequency in evaluable lesions. Despite inducing a reduction in Treg cell numbers in vivo, LMB-2 therapy did not augment the immune response to cancer vaccination and no patient experienced an objective response or autoimmunity. These data demonstrate the capacity of a CD25-directed immunotoxin to selectively mediate a transient partial reduction in circulating and tumor-infiltrating Treg cells in vivo, and suggest that more comprehensive Treg cell elimination may be required to bolster antitumor responses in patients with metastatic melanoma.
Autoantibodies in Canine Masticatory Muscle Myositis Recognize a Novel Myosin Binding Protein-C Family Member
Authors: Wu Xiaohua , Li Zhi-fang , Brooks Randolph , Komives Elizabeth A. , Torpey Justin W. , Engvall Eva , Gonias Steven L. , Shelton G. Diane 
Published: April 2014

Abstract
Inflammatory myopathies are a group of autoimmune diseases that affect muscles. In humans, the most common inflammatory myopathies are polymyositis, dermatomyositis, and inclusion body myositis. Autoantibodies may be found in humans with inflammatory myopathies, and these play an important role in diagnosis and disease classification. However, these Abs are typically not muscle specific. Spontaneously occurring canine inflammatory myopathies may be good parallel disorders and provide insights into human myositis. In dogs with inflammatory myopathy, muscle-specific autoantibodies have been found, especially in masticatory muscle myositis. We have identified the major Ag recognized by the autoantibodies in canine masticatory muscle myositis. This Ag is a novel member of the myosin binding protein-C family, which we call masticatory myosin binding protein-C (mMyBP-C). mMyBP-C is localized not only within the masticatory muscle fibers, but also at or near their cell surface, perhaps making it accessible as an immunogen. The gene for mMyBP-C also exists in humans, and mMyBP-C could potentially play a role in certain human inflammatory myopathies. Understanding the role of mMyBP-C in this canine inflammatory myopathy may advance our knowledge of mechanisms of autoimmune inflammatory muscle diseases, not only in dogs, but also in humans.
Cutting Edge: IL-4-Mediated Protection of Primary B Lymphocytes from Apoptosis via Stat6-Dependent Regulation of Glycolytic Metabolism
Authors: Dufort Fay J. , Bleiman Blair F. , Gumina Maria R. , Blair Derek , Wagner Dean J. , Roberts Mary F. , Abu-Amer Yousef , Chiles Thomas C. 
Published: April 2014

Abstract
IL-4 prevents the death of naive B lymphocytes through the up-regulation of antiapoptotic proteins such as Bcl-xL. Despite studies implicating glucose utilization in growth factor-dependent survival of hemopoietic cells, the role of glucose energy metabolism in maintaining B cell viability by IL-4 is unknown. We show that IL-4 triggers glucose uptake, Glut1 expression, and glycolysis in splenic B cells; this is accompanied by increased cellular ATP. Glycolysis inhibition results in apoptosis, even in the presence of IL-4. IL-4-induced glycolysis occurs normally in B cells deficient in insulin receptor substrate-2 or the p85α subunit of PI3K and is not affected by pretreatment with PI3K or MAPK pathway inhibitors. Stat6-deficient B cells exhibit impaired IL-4-induced glycolysis. Cell-permeable, constitutively active Stat6 is effective in restoring IL-4-induced glycolysis in Stat6-deficient B cells. Therefore, besides controlling antiapoptotic proteins, IL-4 mediates B cell survival by regulating glucose energy metabolism via a Stat6-dependent pathway.