bluuebunny/crossref_metadata_2025_split huggingface dataset:
Distinct T Cell/Renal Tubular Epithelial Cell Interactions Define Differential Chemokine Production: Implications for Tubulointerstitial Injury in Chronic Glomerulonephritides
Authors: Kuroiwa Takashi , Schlimgen Ryan , Illei Gabor G. , McInnes Iain B. , Boumpas Dimitrios T. 
Published: April 2014

AbstractChemokines can promote interstitial fibrosis that is, in turn, a strong predictor of renal failure in chronic glomerulonephritides (GN). Resident renal cells, including renal tubular epithelial cells (RTEC), represent a prominent source of chemokine expression. Evaluating those factors responsible for sustained chemokine production by RTEC during GN is therefore crucial. The contribution of interstitial T cells to such expression, and in particular the precise nature of their interactions with RTEC, are poorly understood. Activated T cell/RTEC coculture induced production of high levels of monocyte chemoattractant protein-1 (MCP-1), RANTES, and IFN-inducible protein-10 from RTEC. Using double-chamber cultures and activated T cell plasma membrane preparations we demonstrated that both cell contact and soluble factors contributed to RTEC chemokine production. Importantly, different chemokines exhibited distinct activation requirements. Thus, for RANTES cell contact was essential, but not sufficient. In contrast, either soluble factors or cell contact induced MCP-1 and IFN-inducible protein-10 production, although both pathways were required for a maximal response. Neutralization experiments identified critical roles in this process for proinflammatory cytokines such as TNF-α, IL-1β, and IFN-γ as well as membrane molecules such as LFA-1, CD40 ligand, and membrane bound TNF-α. Finally, chemotactic bioassays of T cell/RTEC coculture supernatants demonstrated 80% reduction of monocyte migration following MCP-1 neutralization, indicating a dominant role for this chemokine. In summary, activation of renal tubular cells by infiltrating T cells can amplify and perpetuate local inflammatory responses through chemokine production differentially mediated by soluble and cell contact-dependent factors. Recognition of this regulatory diversity has important implications in the choice of potential therapeutic targets in GN.
High Susceptibility for Cystic Fibrosis Human Airway Gland Cells to Produce IL-8 Through the IκB Kinase α Pathway in Response to Extracellular NaCl Content
Authors: Tabary Olivier , Escotte Sandie , Couetil Jean Paul , Hubert Dominique , Dusser Daniel , Puchelle Edith , Jacquot Jacky 
Published: April 2014

Abstract
Increasing evidence suggests that in airways from cystic fibrosis (CF) patients, inflammation may precede bacterial infection and be related to an endogenous dysregulation of proinflammatory cytokines in airway epithelial cells. Several investigators have reported that, in CF airway fluids, elevated NaCl concentrations may also contribute to the diseased state by inhibiting the bactericidal properties of airway fluid. Because many proinflammatory cytokines are transcriptionally regulated by the NF-κB, we investigated whether an elevated extracellular NaCl content in airway fluids significantly impaired the regulation of the NF-κB/IκBα complex and the chemokine IL-8 production in primary non-CF and CF human bronchial gland epithelial cells. Exposure of non-CF gland cells to hypotonic (85 mM) NaCl solution, compared with isotonic (115 mM) NaCl and hypertonic (170 mM) NaCl solutions, resulted in a significant decrease in IL-8 production that was paralleled by a strong inhibition of activated NF-κB associated with an increased cytosolic expression of IκBα and a decrease in the IκB kinase α protein level. In CF gland cells, we demonstrated that, compared with the high IL-8 in an hypertonic solution, the release of IL-8 was significantly reduced 2-fold in an isotonic solution and 5-fold in a hypotonic solution. Strikingly, exposure of CF bronchial gland cells to either hypotonic or isotonic milieu did not result in a marked inhibition of the activated NF-κB/IκBα system. This is the first demonstration that primary human CF bronchial gland cells exhibit abnormally high IL-8 production through constitutively activated NF-κB and high IκB kinase α level, whatever the hypo-, iso-, and hypertonic NaCl milieu.
In Vitro Priming with Adenovirus/gp100 Antigen-Transduced Dendritic Cells Reveals the Epitope Specificity of HLA-A*0201-Restricted CD8+ T Cells in Patients with Melanoma
Authors: Linette Gerald P. , Shankara Srinivas , Longerich Simonne , Yang Sixun , Doll Rhonda , Nicolette Charles , Preffer Frederic I. , Roberts Bruce L. , Haluska Frank G. 
Published: April 2014

AbstractReplication-deficient recombinant adenovirus (Ad) encoding human gp100 or MART-1 melanoma Ag was used to transduce human dendritic cells (DC) ex vivo as a model system for cancer vaccine therapy. A second generation E1/E4 region deleted Ad which harbors the CMV immediate-early promoter/enhancer and a unique E4-ORF6/pIX chimeric gene was employed as the backbone vector. We demonstrate that human monocyte-derived DC are permissive to Ad infection at multiplicity of infection between 100 and 500 and occurs independent of the coxsackie Ad receptor. Fluorescent-labeled Ad was used to assess the kinetics and distribution of viral vector within DC. Ad-transduced DC show peak transgene expression at 24–48 h and expression remains detectable for at least 7 days. DC transduced with replication-deficient Ad do not exhibit any unusual phenotypic characteristics or cytopathic effects. DC transduced with Ad2/gp100v2 can elicit tumor-specific CTL in vitro from patients bearing gp100+ metastatic melanoma. Using a panel of gp100-derived synthetic peptides, we show that Ad2/gp100v2-transduced DC elicit Ag-specific CTL that recognize only the G209 and G280 epitopes, both of which display relatively short half-lives (∼7–8 h) on the surface of HLA-A*0201+ cells. Thus, patients with metastatic melanoma are not tolerant to gp100 Ag based on the detection of CD8+ T cells specific for multiple HLA-A*0201-restricted, gp100-derived epitopes.
Prediction of the Immunodominant Epitope of the Pyruvate Dehydrogenase Complex E2 in Primary Biliary Cirrhosis Using Phage Display
Authors: Rowley Merrill J. , Scealy Marita , Whisstock James C. , Jois Jennifer A. , Wijeyewickrema Lakshmi C. , Mackay Ian R. 
Published: April 2014

Abstract
Primary biliary cirrhosis (PBC) is an autoimmune liver disease characterized by autoantibodies reactive with the pyruvate dehydrogenase complex. A conformational epitope has been mapped to aa 91–227 within the inner lipoyl domain of the E2 subunit (pyruvate dehydrogenase complex E2 (PDC-E2)). We have used phage display to further localize this epitope. A random heptapeptide library was screened using IgG from two patients with PBC, with negative selection using pooled normal IgG. Phage that contained peptide inserts (phagotopes) selected using PBC sera differed from those selected using IgG from patients with RA or polychondritis. Two motifs occurred only among the PBC-selected phagotopes; these were MH (13 sequences, 16 phagotopes) and FV (FVEHTRW, FVEIYSP, FVLPWRI). The phagotopes selected were tested for reactivity with anti-PDC-E2 affinity purified from four patients with PBC. Phagotopes that contained 1 of 15 different peptide sequences were reactive with one or more of these four anti-PDC-E2 preparations, whereas phagotopes that contained 1of the remaining 28 sequences were negative. The peptides (FVLPWRI, MHLNTPP, MHLTQSP) encoded by three phagotopes that were strongly reactive with all four preparations of anti-PDC-E2 were synthesized. Each of the selected peptides, but not an irrelevant peptide, inhibited the reactivity by ELISA of PBC serum with recombinant PDC-E2 and reduced the inhibition of the enzyme activity of PDC by a PBC serum. The peptide sequences, along with the known NMR structure of the inner lipoyl domain of PDC-E2, allow the prediction of nonsequential residues 131HM132 and 178FEV180 that contribute to a conformational epitope.
Cutting Edge: Infection by the Agent of Human Granulocytic Ehrlichiosis Prevents the Respiratory Burst by Down-Regulatinggp91phox
Authors: Banerjee Rila , Anguita Juan , Roos Dirk , Fikrig Erol 
Published: April 2014

AbstractThe agent of human granulocytic ehrlichiosis (HGE) is an emerging tick-borne pathogen that resides in neutrophils and can be cultured in a promyelocytic (HL-60) cell line. In response to microbes, polymorphonuclear leukocytes normally activate the NADPH oxidase enzyme complex and generate superoxide anion (O2−). However, HL-60 cells infected with HGE bacteria did not produce O2− upon activation with PMA. RT-PCR demonstrated that HGE organisms inhibited mRNA expression of a single component of NADPH oxidase, gp91phox, and FACS analysis showed that plasma membrane-associated gp91phox protein was reduced on the infected cells. Infection with HGE organisms also decreased gp91phox mRNA levels in splenic neutrophils in a murine model of HGE, demonstrating this phenomenon in vivo. Therefore, HGE bacteria repress the respiratory burst by down-regulating gp91phox, the first direct inhibition of NADPH oxidase by a pathogen.
Cutting Edge: Increased Expression of Bcl-2 in Antigen-Specific Memory CD8+ T Cells
Authors: Grayson Jason M. , Zajac Allan J. , Altman John D. , Ahmed Rafi 
Published: April 2014

Abstract
Bcl-2 plays a critical role in regulating cell survival and apoptosis. We examined Bcl-2 expression in virus-specific CD8 T cells during the expansion, death, and memory phases of the T cell response following infection of mice with lymphocytic choriomeningitis virus (LCMV). Naive CD8 T cells expressed a basal level of Bcl-2 that was down-regulated in effector CD8 T cells just before the death phase. Bcl-2 levels remained low during the death phase but surviving memory CD8 T cells expressed higher levels of Bcl-2 than naive cells. These changes were shown to occur in LCMV TCR transgenic cells as well as virus-specific CD8 T cells in C57BL/6 and BALB/c mice identified by MHC class I tetramers. In all instances, memory CD8 T cells expressed higher levels of Bcl-2, suggesting that increased Bcl-2 expression plays a role in the long-term maintenance of memory CD8 T cells in vivo.
Cutting Edge: Ectopic Expression of the Chemokine TCA4/SLC Is Sufficient to Trigger Lymphoid Neogenesis
Authors: Fan Lian , Reilly Christina R. , Luo Yi , Dorf Martin E. , Lo David 
Published: April 2014

AbstractTo test whether accumulation of naive lymphocytes is sufficient to trigger lymphoid development, we generated mice with islet expression of the chemokine TCA4/SLC. This chemokine is specific for naive lymphocytes and mature dendritic cells (DC) which express the CCR7 receptor. Islets initially developed accumulations of T cells with DC, with scattered B cells at the perimeter. These infiltrates consolidated into organized lymphoid tissue, with high endothelial venules and stromal reticulum. Infiltrate lymphocytes showed a naive CD44low CD25− CD69− phenotype, though half were CD62L negative. When backcrossed to RAG-1 knockout, DC were not recruited. Interestingly, islet lymphoid tissue developed in backcrosses to Ikaros knockout mice despite the absence of normal peripheral nodes. Our results indicate that TCA4/SLC can induce the development and organization of lymphoid tissue through diffential recruitment of T and B lymphocytes and secondary effects on stromal cell development.
Persistence of Physiological Self Antigen Is Required for the Regulation of Self Tolerance
Authors: Garza Kristine M. , Agersborg Sally S. , Baker Elizabeth , Tung Kenneth S. K. 
Published: April 2014

AbstractEndogenous Ag requirement for induction and maintenance of T cell tolerance has been extensively investigated in mice that express a transgenic Ag and/or its cognate transgenic TCR. In contrast, studies on tolerance for physiologically expressed self Ag and normal T cells are limited. Herein, we showed that the murine ovarian-specific ZP3 Ag is detectable from birth. Tolerance to ZP3 is detected in female relative to male mice. In comparison to males, 100-fold more ovarian peptide (pZP3) is required to elicit a comparable pathogenic response in females. Female tolerance to pZP3 was dependent on the presence of endogenous ovarian Ag, because neonatal ovariectomy converted the female response to that of males. Moreover, in female mice that were ovariectomized from the ages of 1–6 wk, the pZP3 responses were enhanced to the male level if ovaries were removed up to 7 days, but not 3 days, before adult challenge with pZP3. Thus, the physiologically expressed ZP3 Ag induces tolerance to pZP3, and the maintenance of tolerance is critically dependent on the continuous presence of the endogenous ovarian Ag. In contrast, exposure to endogenous ovarian Ag confined to the neonatal period is insufficient for the induction and maintenance of tolerance to ZP3.
Engagement of CD28 Modulates CXC Chemokine Receptor 4 Surface Expression in Both Resting and CD3-Stimulated CD4+ T Cells
Authors: Secchiero Paola , Zella Davide , Curreli Sabrina , Mirandola Prisco , Capitani Silvano , Gallo Robert C. , Zauli Giorgio 
Published: April 2014

AbstractOptimal CD4+ T cell activation requires the cooperation of multiple signaling pathways coupled to the TCR-CD3 complex and to the CD28 costimulatory molecule. In this study, we have investigated the expression of surface CXC chemokine receptor 4 (CXCR4) in enriched populations of CD4+ T PBL, stimulated with anti-CD3 and anti-CD28 mAbs, immobilized on plastic. Anti-CD3 alone induced a progressive down-regulation of surface CXCR4, accompanied by a significant decline in the entry of the HXB2 T cell line-tropic (X4-tropic) HIV-1 clone in CD4+ T cells. Of note, this effect was strictly dependent on the presence in culture of CD14+ monocytes. On the other hand, anti-CD28 alone induced a small but reproducible increase in the expression of surface CXCR4 as well as in the entry of HXB2 HIV-1 clone in resting CD4+ T cells. When the two mAbs were used in combination, anti-CD28 potently synergized with anti-CD3 in inducing the expression of CD69 activation marker and stimulating the proliferation of CD4+ T cells. On the other hand, anti-CD28 counteracted the CXCR4 down-modulation induced by anti-CD3. The latter effect was particularly evident when anti-CD28 was associated to suboptimal concentrations of anti-CD3. Because CXCR4 is the major coreceptor for the highly cytopathic X4-tropic HIV-1 strains, which preferentially replicate in proliferating CD4+ T cells, the ability of anti-CD28 to up-regulate the surface expression of CXCR4 in both resting and activated CD4+ T cells provides one relevant mechanism for the progression of HIV-1 disease.
The CC Chemokine CKβ-11/MIP-3β/ELC/Exodus 3 Mediates Tumor Rejection of Murine Breast Cancer Cells Through NK Cells
Authors: Braun Stephen E. , Chen Keyue , Foster Richard G. , Kim Chang H. , Hromas Robert , Kaplan Mark H. , Broxmeyer Hal E. , Cornetta Kenneth 
Published: April 2014

AbstractCKβ-11 chemoattracts T cells, B cells, dendritic cells, macrophage progenitors, and NK cells and facilitates dendritic cell and T cell interactions in secondary lymphoid tissues. We hypothesized that expression of CKβ-11 in tumor cells may generate antitumor immunity through these interactions. After transduction with the retroviral vector L(CKβ11)SN, the murine breast cancer cell line C3L5 (C3L5-CKβ11) showed expression of retroviral mRNA by Northern analysis and production of functional CKβ-11 by chemotaxis of human NK cells to C3L5-CKβ11 supernatant. Only 10% of mice injected with C3L5-CKβ11 developed tumors, compared with 100% of mice injected with a transduced control C3L5 line (C3L5-G1N). Importantly, the in vitro growth characteristics of the CKβ-11-transduced cell line were unaffected, suggesting the difference in growth in vivo was a result of chemokine production. Vaccination with C3L5-CKβ11 partially protected animals from parental C3L5 challenge. Immunodepletion with anti-asialo-GM1 or anti-CD4 during C3L5-CKβ11 vaccination significantly reduced CKβ-11 antitumor activity compared with control and anti-CD8-treated groups. Splenocytes from NK-depleted animals transferred the acquired immunity generated with C3L5-CKβ11 vaccination, while splenocytes from the CD4-depleted animals did not. These results indicate, for the first time, that expression of CKβ-11 in a breast cancer cell line mediates rejection of the transduced tumor through a mechanism involving NK and CD4+ cells. Furthermore, CKβ-11-transduced tumor cells generate long-term antitumor immunity that requires CD4+ cells. These studies demonstrate the potential role of CKβ-11 as an adjuvant in stimulating antitumor responses.
Caspase Enzyme Activity Is Not Essential for Apoptosis During Thymocyte Development
Authors: Doerfler Petra , Forbush Katherine A. , Perlmutter Roger M. 
Published: April 2014

Abstract
Caspases, a family of cysteine proteases, are critical mediators of apoptosis. To address the importance of caspases in thymocyte development, we have generated transgenic mice that express the baculovirus protein p35, a viral caspase inhibitor, specifically in the thymus. p35 expression inhibited Fas (CD95)-, CD3-, or peptide-induced caspase activity in vitro and conferred resistance to Fas-induced apoptosis. However, p35 did not block specific peptide-induced negative selection in OT1 and HY TCR transgenic mouse models. Even the potent pharmacological caspase inhibitor zVAD-FMK (benzyloxycarbonyl-Val-Ala-Asp-fluoromethyl-ketone) could not prevent peptide-induced deletion of OT1 thymocytes, although it improved basal thymocyte survival in vitro. Moreover, the developmental block observed in rag1−/− thymocytes, which lack pre-TCR signaling, was also not rescued by p35 expression. These results indicate that caspase-independent signal transduction pathways can mediate thymocyte death during normal T cell development.
Contributions of CD8+ T Cells and Viral Spread to Demyelinating Disease
Authors: Marten Norman W. , Stohlman Stephen A. , Atkinson Roscoe D. , Hinton David R. , Fleming John O. , Bergmann Cornelia C. 
Published: April 2014

AbstractAcute and chronic demyelination are hallmarks of CNS infection by the neurotropic JHM strain of mouse hepatitis virus. Although infectious virus is cleared by CD8+ T cells, both viral RNA and activated CD8+ T cells remain in the CNS during persistence potentially contributing to pathology. To dissociate immune from virus-mediated determinants initiating and maintaining demyelinating disease, mice were infected with two attenuated viral variants differing in a hypervariable region of the spike protein. Despite similar viral replication and tropism, one infection was marked by extensive demyelination and paralysis, whereas the other resulted in no clinical symptoms and minimal neuropathology. Mononuclear cells from either infected brain exhibited virus specific ex vivo cytolytic activity, which was rapidly lost during viral clearance. As revealed by class I tetramer technology the paralytic variant was superior in inducing specific CD8+ T cells during the acute disease. However, after infectious virus was cleared, twice as many virus-specific IFN-γ-secreting CD8+ T cells were recovered from the brains of asymptomatic mice compared with mice undergoing demyelination, suggesting that IFN-γ ameliorates rather than perpetuates JHM strain of mouse hepatitis virus-induced demyelination. The present data thus indicate that in immunocompetent mice, effector CD8+ T cells control infection without mediating either clinical disease or demyelination. In contrast, demyelination correlated with early and sustained infection of the spinal cord. Rapid viral spread, attributed to determinants within the spike protein and possibly perpetuated by suboptimal CD8+ T cell effector function, thus ultimately leads to the process of immune-mediated demyelination.
Metabolism of Recombination Coding Ends in scid Cells
Authors: Brown Matthew L. , Chang Yung 
Published: April 2014

Abstract
V(D)J recombination cleavage generates two types of dsDNA breaks: blunt signal ends and covalently sealed hairpin coding ends. Although signal ends can be directly ligated to form signal joints, hairpin coding ends need to be opened and subsequently processed before being joined. However, the underlying mechanism of coding end resolution remains undefined. The current study attempts to delineate this process by analyzing various structures of coding ends made in situ from recombination-inducible pre-B cell lines of both normal and scid mice. These cell lines were derived by transformation of B cell precursors with the temperature-sensitive Abelson murine leukemia virus. Our kinetic analysis revealed that under conditions permissive to scid transformants, hairpin coding ends could be nicked to generate 3′ overhangs and then processed into blunt ends. The final joining of these blunt ends followed the same kinetics as signal joint formation. The course of this process is in sharp contrast to coding end resolution in scid heterozygous transformants that express the catalytic subunit of DNA-dependent protein kinase, in which hairpin end opening, processing, and joining proceeded very rapidly and appeared to be closely linked. Furthermore, we demonstrated that the opening of hairpin ends in scid cells could be manipulated by different culture conditions, which ultimately influenced not only the level and integrity of the newly formed coding joints, but also the extent of microhomology at the coding junctions. These results are discussed in the context of scid leaky recombination.
Methylation of Class IItrans-Activator Promoter IV: A Novel Mechanism of MHC Class II Gene Control
Authors: Morris Ann C. , Spangler Wendi E. , Boss Jeremy M. 
Published: April 2014

AbstractInhibition of class II trans-activator (CIITA) expression prevents embryonic trophoblast cells from up-regulating MHC class II genes in response to IFN-γ. This is thought to be one mechanism of maternal tolerance to the fetal allograft. The CIITA gene is regulated by four distinct promoters; promoter III directs constitutive (B cell) expression, and promoter IV regulates IFN-γ-inducible expression. Using in vivo genomic footprinting, promoter-reporter analysis, Southern blot analysis, and RT-PCR, we have examined the cause of CIITA silencing in a trophoblast-derived cell line. We report here that methylation of promoter IV DNA at CpG sites in Jar cells prevents promoter occupancy and IFN-γ-inducible transcription. The inhibition of CpG methylation in Jar cells by treatment with 5-aza-2′-deoxycytidine restores IFN-γ inducibility to CIITA. This is the first description of an epigenetic mechanism involved in regulation of CIITA and MHC class II gene expression.