bluuebunny/crossref_metadata_2025_split huggingface dataset:
Annexin 1 Modulates Monocyte-Endothelial Cell Interaction In Vitro and Cell Migration In Vivo in the Human SCID Mouse Transplantation Model
Authors: Perretti Mauro , Ingegnoli Francesca , Wheller Samantha K. , Blades Mark C. , Solito Egle , Pitzalis Costantino 
Published: April 2014

AbstractThe effect of the glucocorticoid inducible protein annexin 1 (ANXA1) on the process of monocytic cell migration was studied using transfected U937 cells expressing variable protein levels. An antisense (AS) (36.4AS; ∼50% less ANXA1) and a sense (S) clone (15S; overexpressing the bioactive 24-kDa fragment) together with the empty plasmid CMV clone were obtained and compared with wild-type U937 cells in various models of cell migration in vitro and in vivo. 15S-transfected U937 cells displayed a reduced (50%) degree of trans-endothelial migration in response to stromal cell-derived factor-1α (CXC chemokine ligand 12 (CXCL12)). In addition, the inhibitory role of endogenous ANXA1 on U937 cell migration in vitro was confirmed by the potentiating effect of a neutralizing anti-ANXA1 serum. Importantly, overexpression of ANXA1 in clone 15S inhibited the extent of cell migration into rheumatoid synovial grafts transplanted into SCID mice. ANXA1 inhibitory effects were not due to modifications in adhesion molecule or CXCL12 receptor (CXCR4) expression as shown by the similar amounts of surface molecules found in transfected and wild-type U937 cells. Likewise, an equal chemotactic response to CXCL12 in vitro excluded an intrinsic defect in cell motility in clones 15S and 36.4AS. These data strongly support the notion that ANXA1 critically interferes with a leukocyte endothelial step essential for U937 cell, and possibly monocyte, transmigration both in vitro and in vivo.
Nitric Oxide Stimulates Macrophage Inflammatory Protein-2 Expression in Sepsis
Authors: Skidgel Randal A. , Gao Xiao-pei , Brovkovych Viktor , Rahman Arshad , Jho David , Predescu Sanda , Standiford Thedodore J. , Malik Asrar B. 
Published: April 2014

AbstractNO is a crucial mediator of the inflammatory response, but its in vivo role as a determinant of lung inflammation remains unclear. We addressed the in vivo role of NO in regulating the activation of NF-κB and expression of inflammatory proteins using an in vivo mouse model of sepsis induced by i.p. injection of Escherichia coli. We observed time-dependent degradation of IκB and activation of NF-κB accompanied by increases in inducible NOS, macrophage inflammatory protein-2 (MIP-2), and ICAM-1 expression after E. coli challenge, which paralleled the ability of lung tissue to produce high-output NO. To determine the role of NO in this process, mice were pretreated with the NO synthase (NOS) inhibitor NG-methyl-l-arginine. Despite having relatively modest effects on NF-κB activation and ICAM-1 or inducible NOS expression, the NOS inhibitor almost completely inhibited expression of MIP-2 in response to E. coli challenge. These responses were associated with the inhibition of migration of neutrophils in lung tissue and increased permeability induced by E. coli. In mice pretreated with NG-methyl-l-arginine, coadministration of E. coli with the NO donor (Z)-1-[N-(2-aminoethyl)-N-(2-ammonioethyl)amino]diazen-1-ium-1,2-diolate substantially restored MIP-2 expression but decreased ICAM-1 expression. The results suggest that NO generated after administration of E. coli serves as an important proinflammatory signal to up-regulate MIP-2 expression in vivo. Thus, NO production in high quantities may be important in the mechanism of amplification of the lung inflammatory response associated with sepsis.
Complement C3a and C5a Induce Different Signal Transduction Cascades in Endothelial Cells
Authors: Schraufstatter Ingrid U. , Trieu Khanh , Sikora Lyudmila , Sriramarao P. , DiScipio Richard 
Published: April 2014

Abstract
In leukocytes, C3a and C5a cause chemotaxis in a Gi-dependent, pertussis toxin (PT)-sensitive fashion. Because we found that HUVECs and immortalized human dermal microvascular endothelial cells express small numbers of C3aRs and C5aRs, we asked what the function of these receptors was on these cells. Activation of the C3aR caused transient formation of actin stress fibers, which was not PT-sensitive, but depended on rho activation implying coupling to Gα12 or Gα13. Activation of the C5aR caused a delayed and sustained cytoskeletal response, which was blocked by PT, and resulted in cell retraction, increased paracellular permeability, and facilitated eosinophil transmigration. C5a, but not C3a, was chemotactic for human immortalized dermal microvascular endothelial cells. The response to C5a was blocked by inhibitors of phosphatidylinositol-3-kinase, src kinase, and of the epidermal growth factor (EGF) receptor (EGFR) as well as by neutralizing Abs against the EGFR and heparin-binding EGF-like factor. Furthermore, immune precipitations showed that the EGFR was phosphorylated following stimulation with C5a. The C5aR in endothelial cells thus uses a signaling cascade–transactivation of the EGFR–that does not exist in leukocytes, while the C3aR couples to a different G protein, presumably Gα12/13.
Lipopolysaccharide-Induced Leukocyte-Endothelial Cell Interactions: A Role for CD14 Versus Toll-Like Receptor 4 Within Microvessels
Authors: Andonegui Graciela , Goyert Sanna M. , Kubes Paul 
Published: April 2014

AbstractThe objective of this study was to systematically assess leukocyte-endothelial cell interactions in vivo in response to LPS in CD14-deficient (CD14−/−) and Toll-like receptor 4-deficient (TLR4d; C3H/HeJ) mice. Local injection of LPS (0.05 μg/kg) into muscle at a concentration that did not cause systemic effects produced a significant reduction in the speed with which leukocytes roll and a substantial increase in leukocyte adhesion and emigration 4 h postinjection. There was no response to LPS in the muscle microvasculature of CD14−/− mice or TLR4d animals. Systemic LPS induced leukopenia and significant sequestration of neutrophils in lungs in wild-type mice but not in CD14−/− or TLR4d mice. P-selectin expression was examined in numerous mouse organs using a dual radiolabeling mAb technique. The results revealed a 20- to 50-fold increase in P-selectin expression in response to LPS in all wild-type tissues examined but no response in any TLR4d tissues. Surprisingly, there was consistently a partial, significant increase in P-selectin expression in numerous microvasculatures including skin and pancreas, but no increase in P-selectin was detected in lung, muscle, and other organs in CD14−/− mice in response to LPS. Next, the skin and muscle microcirculation were visualized using intravital microscopy after systemic LPS treatment, and the results confirmed a CD14-independent mechanism of leukocyte sequestration in skin but not muscle. In summary, our results suggest that the LPS-induced leukocyte sequestration to some tissues is entirely dependent on both CD14 and TLR4 but there are CD14-independent, TLR4-dependent endothelial cell responses in some microvascular beds.
E- and P-Selectins Are Essential for the Development of Cockroach Allergen-Induced Airway Responses
Authors: Lukacs Nicholas W. , John Alison , Berlin Aaron , Bullard Daniel C. , Knibbs Randall , Stoolman Lloyd M. 
Published: April 2014

AbstractPeribronchial inflammation contributes to the pathophysiology of allergic asthma. In many vascular beds, adhesive interactions between leukocytes and the endothelial surface initiate the recruitment of circulating cells. Previous studies using OVA-induced airway hyperreactivity indicated that P-selectin, a member of the selectin family expressed by activated platelets and endothelium, contributed to both inflammation and bronchoconstriction. The current study used cockroach allergen (CRA), an allergen that induces asthmatic responses in both humans and mice, to further investigate the role of selectins in the development of peribronchial inflammation and airway hyperreactivity. P- and E-selectin mRNAs were detected in extracts of CRA-sensitized animals beginning shortly after intratracheal challenge with CRA. The P-selectin mRNA was transiently induced at early time points while up-regulation of the E-selectin mRNA was more prolonged. Mice with targeted deletions in E-selectin (E−), P-selectin (P−), and both genes (E−/P−) showed 70–85% reductions in airway hyperreactivity, peribronchial inflammation, and eosinophil accumulation. The P− and E−/P− groups showed the most profound reductions. The transfer of splenic lymphocytes from CRA-primed E−/P− into naive wild-type (WT) mice produced the same level of airway hyperreactivity as transfers from CRA-primed WT into naive WT hosts, indicating that peripheral immunization was similar. The observed changes in the selectin-deficient animals were not related to inadequate sensitization, because CRA priming and challenge increased serum IgE levels. Furthermore, pulmonary Th2-type cytokines and chemokines in the E-selectin−/− and WT animals were similar. The findings indicate that both P- and E-selectin contribute to CRA-induced peribronchial inflammation and airway hyperreactivity.
Mice Deficient in Complement Receptors 1 and 2 Lack a Tissue Injury-Inducing Subset of the Natural Antibody Repertoire
Authors: Fleming Sherry D. , Shea-Donohue Terez , Guthridge Joel M. , Kulik Liudmila , Waldschmidt Thomas J. , Gipson Matthew G. , Tsokos George C. , Holers V. Michael 
Published: April 2014

AbstractIntestinal ischemia-reperfusion (IR) injury is initiated when natural Abs recognize neoantigens that are revealed on ischemic cells. Cr2−/− mice, deficient in complement receptors (CR)1 and CR2, demonstrate defects in T-dependent B-2 B cell responses to foreign Ags and have also been suggested to manifest abnormalities of the B-1 subset of B lymphocytes. To determine whether these CRs might play a role in the generation of the natural Abs that initiate intestinal IR injury, we performed experiments in Cr2−/− and control Cr2+/+ mice. We found that Cr2−/− mice did not demonstrate severe intestinal injury that was readily observed in control Cr2+/+ mice following IR, despite having identical serum levels of IgM and IgG. Pretreatment of Cr2−/− mice before the ischemic phase with IgM and IgG purified from the serum of wild-type C57BL/6 mice reconstituted all key features of IR injury, demonstrating that the defect involves the failure to develop this subset of natural Abs. Pretreatment with IgM and IgG individually demonstrates that each contributes to unique features of IR injury. In sum, CR2/CR1 play an unanticipated but critical role in the development of a subset of the natural Ab repertoire that has particular importance in the pathogenesis of IR injury.
Ras Activation in T Cells Determines the Development of Antigen-Induced Airway Hyperresponsiveness and Eosinophilic Inflammation
Authors: Shibata Youichi , Kamata Tohru , Kimura Motoko , Yamashita Masakatsu , Wang Chrong-Reen , Murata Kaoru , Miyazaki Masaru , Taniguchi Masaru , Watanabe Naohiro , Nakayama Toshinori 
Published: April 2014

Abstract
The central role for Th2 cells in the development of Ag-induced airway hyperresponsiveness and eosinophilic inflammation is well documented. We have reported a crucial role for TCR-induced activation of the Ras/extracellular signal-regulated kinase mitogen-activated protein kinase cascade in Th2 cell differentiation. Here, we show that the development of both OVA-induced airway hyperresponsiveness and eosinophilic airway inflammation in a mouse asthma model are attenuated in transgenic mice by the overexpression of enzymatically inactive Ras molecules in T cells. In addition, reduced levels of IL-5 production and eosinophilic inflammation induced by nematode infection (Nippostrongylus brasiliensis or Heligmosomoides polygyrus) were detected. Thus, the level of Ras activation in T cells appears to determine Th2-dependent eosinophilic inflammation and Ag-induced airway hyperresponsiveness.
A Spontaneous CD8 T Cell-Dependent Autoimmune Disease to an Antigen Expressed Under the Human Keratin 14 Promoter
Authors: McGargill Maureen A. , Mayerova Dita , Stefanski Heather E. , Koehn Brent , Parke Evan A. , Jameson Stephen C. , Panoskaltsis-Mortari Angela , Hogquist Kristin A. 
Published: April 2014

Abstract
Using a previously described human keratin 14 (K14) promoter, we created mice expressing a peptide Ag (OVAp) in epithelial cells of the skin, tongue, esophagus, and thymus. Double transgenic mice that also express a TCR specific for this Ag (OT-I) showed evidence for Ag-driven receptor editing in the thymus. Surprisingly, such mice exhibited a severe autoimmune disease. In this work we describe the features of this disease and demonstrate that it is dependent on CD8 T cells. Consistent with the Ag expression pattern dictated by the human K14 promoter, an inflammatory infiltrate was observed in skin and esophagus and around bile ducts of the liver. We also observed a high level of TNF-α in the serum. Given that Ag expression in the thymus induced development of T cells with dual TCR reactivity, and that dual-reactive cells have been suggested to have autoimmune potential, we tested whether they were a causal factor in the disease observed here. We found that OT-I/K14-OVAp animals on a recombinase-activating gene-deficient background still suffered from disease. In addition, OT-I animals expressing OVA broadly in all tissues under a different promoter did not experience disease, despite having a similar number of dual-specific T cells. Thus, in this model it would appear that dual-reactive T cells do not underlie autoimmune pathology. Finally, we extended these observations to a second transgenic system involving 2C TCR-transgenic animals expressing the SIY peptide Ag with the hK14 promoter. We discuss the potential relationship between autoimmunity and self-Ags that are expressed in stratified epithelium.
IL-10 Regulates Murine Lupus
Authors: Yin Zhinan , Bahtiyar Gul , Zhang Na , Liu Lanzhen , Zhu Ping , Robert Marie E. , McNiff Jennifer , Madaio Michael P. , Craft Joe 
Published: April 2014

AbstractMRL/MpJ-Tnfrsf6lpr (MRL/MpJ-Faslpr; MRL-Faslpr) mice develop a spontaneous lupus syndrome closely resembling human systemic lupus erythematosus. To define the role of IL-10 in the regulation of murine lupus, IL-10 gene-deficient (IL-10−/−) MRL-Faslpr (MRL-Faslpr IL-10−/−) mice were generated and their disease phenotype was compared with littermates with one or two copies of an intact IL-10 locus (MRL-Faslpr IL-10+/− and MRL-Faslpr IL-10+/+ mice, respectively). MRL-Faslpr IL-10−/− mice developed severe lupus, with earlier appearance of skin lesions, increased lymphadenopathy, more severe glomerulonephritis, and higher mortality than their IL-10-intact littermate controls. The increased severity of lupus in MRL-Faslpr IL-10−/− mice was closely associated with enhanced IFN-γ production by both CD4+ and CD8+ cells and increased serum concentration of IgG2a anti-dsDNA autoantibodies. The protective effect of IL-10 in this lupus model was further supported by the observation that administration of rIL-10 reduced IgG2a anti-dsDNA autoantibody production in wild-type MRL-Faslpr animals. In summary, our results provide evidence that IL-10 can down-modulate murine lupus through inhibition of pathogenic Th1 cytokine responses. Modulation of the level of IL-10 may be of potential therapeutic benefit for human lupus.
Transdifferentiation of Cardiac Fibroblasts, a Fetal Factor in Anti-SSA/Ro-SSB/La Antibody-Mediated Congenital Heart Block
Authors: Clancy Robert M. , Askanase Anca D. , Kapur Raj P. , Chiopelas Efstathia , Azar Natalie , Miranda-Carus M. Eugenia , Buyon Jill P. 
Published: April 2014

AbstractThe signature lesion of autoantibody-associated congenital heart block (CHB) is fibrosis of the conducting tissue. To date, participation of myofibroblasts in the cascade to injury has been unexplored. The importance of myofibroblast/macrophage cross-talk is demonstrated by the novel finding of these cell types in the heart of a neonate dying of CHB. This clue to pathogenesis prompted consideration of the mechanism by which maternal anti-SSA/Ro-SSB/La Abs initiate an inflammatory response and promote fibrosis. Isolated cardiocytes from 16–24 wk abortuses were rendered apoptotic by exposure to poly (2-) hydroxyethylmethacrylate; flow cytometry confirmed surface expression of Ro/La. Apoptotic cardiocytes were incubated with affinity-purified Abs to 52 and 60 kDa Ro from CHB mothers (opsonized) or IgG fractions from healthy donors (nonopsonized). Macrophages cultured with opsonized apoptotic cardiocytes expressed proinflammatory markers, supported by a three-fold increase in active αVβ3 integrin. Fetal cardiac fibroblasts exposed to supernatants obtained from macrophages incubated with opsonized apoptotic cardiocytes (but not nonopsonized) dramatically increased expression of the myofibroblast marker α-smooth muscle actin (SMAc). The “opsonized” supernatant reversed an inhibitory effect of the “nonopsonized” supernatant on proliferation of fibroblasts (120 vs 69%, p &lt; 0.05). Parallel experiments examined the effects of two cytokines and their neutralizing Abs on fibroblasts. TGFβ1 increased SMAc staining but decreased proliferation. TNF-α did not affect either readout. Addition of anti-TGFβ1 Abs to the “opsonized” supernatant blocked SMAc expression but increased proliferation, while anti-TNF-α blocking Abs had no effects. These data suggest that transdifferentiation of cardiac fibroblasts to a scarring phenotype is a pathologic process initiated by maternal Abs.
Efficient Generation of Antigen-Specific Cytotoxic T Cells Using Retrovirally Transduced CD40-Activated B Cells
Authors: Kondo Eisei , Topp Max S. , Kiem Hans-Peter , Obata Yuichi , Morishima Yasuo , Kuzushima Kiyotaka , Tanimoto Mitsune , Harada Mine , Takahashi Toshitada , Akatsuka Yoshiki 
Published: April 2014

Abstract
The development of rapid, efficient, and safe methods for generating Ag-specific T cells is necessary for the clinical application of adoptive immunotherapy. We show that B cells stimulated with CD40 ligand and IL-4 (CD40-B cells) can be efficiently transduced with retroviral vectors encoding a model Ag, CMV tegument protein pp65 gene, and maintain high levels of costimulatory molecules after gene transfer. CTL lines specific for pp65 were readily generated in all four healthy CMV-seropositive donors by stimulating autologous CD8+ T cells with these transduced CD40-B cells, both of which were derived from 10 ml peripheral blood. ELISPOT assays revealed that the CTL lines used multiple HLA alleles as restricting elements. Thus, CD40-B cells transduced retrovirally with Ag-encoding cDNA can be potent APC and facilitate to generate Ag-specific CTL in vitro.
Inhibition of EBV-Induced Lymphoproliferation by CD4+ T Cells Specific for an MHC Class II Promiscuous Epitope
Authors: Omiya Ryusuke , Buteau Chantal , Kobayashi Hiroya , Paya Carlos V. , Celis Esteban 
Published: April 2014

AbstractPosttransplant lymphoproliferative disorder (PTLD) and B cell lymphomas induced by EBV continue to be a major life-threatening complication in transplant patients. The establishment and enhancement of T cell immunity to EBV before transplantation and immunosuppressive therapy could help diminish these complications, but the lack of an effective vaccine has limited this prophylactic approach. We describe here the identification of a peptide epitope from the EBV EBNA2 Ag that is capable of inducing in vitro CD4+ T cell responses that inhibit the EBV-mediated B lymphocyte proliferation associated with PTLD. Most significantly, T cell responses to the EBNA2 epitope were found to be restricted by numerous MHC class II alleles (DR1, DR7, DR16, DR52, DQ2, and DQ7), indicating that this peptide is highly promiscuous and would be recognized by a large proportion (&gt;50%) of the general population. These results are relevant for the design of a simple, inexpensive and widely applicable peptide-based vaccine to prevent PTLD in solid organ transplant patients.
Suppression of Experimental Autoimmune Encephalomyelitis Using Peptide Mimics of CD28
Authors: Srinivasan Mythily , Gienapp Ingrid E. , Stuckman Scott S. , Rogers Connie J. , Jewell Scott D. , Kaumaya Pravin T. P. , Whitacre Caroline C. 
Published: April 2014

AbstractThe B7:CD28/CTLA-4 costimulatory pathway plays a critical role in regulating the immune response and thus provides an ideal target for therapeutic manipulation of autoimmune disease. Previous studies have shown that blockade of CD28 signaling by mAbs can both prevent and exacerbate experimental autoimmune encephalomyelitis (EAE). In this study, we have designed two CD28 peptide mimics that selectively block B7:CD28 interactions. By surface plasmon resonance, both the end group-blocked CD28 peptide (EL-CD28) and its retro-inverso isomer (RI-CD28) compete effectively with the extracellular domain of CD28 for binding to B7-1. Both the CD28 peptide mimics inhibited expansion of encephalitogenic T cells in vitro. A single administration of EL-CD28 or RI-CD28 peptide significantly reduced disease severity in EAE. Importantly, we show that either CD28 peptide mimic administered during acute disease dramatically improved clinical signs of EAE, suppressing ongoing disease. The ratio of CD80:CD86 expression was significantly lower on CD4+ and F4/80+ spleen cells in CD28 peptide-treated mice. Peripheral deletion of Ag-specific CD4+ T cells occurs following in vivo blockade of CD28 with synthetic CD28 peptides.
Streptococcus sanguisModulates Type II Collagen-Induced Arthritis in DBA/1J Mice
Authors: Costalonga Massimo , Hodges James S. , Herzberg Mark C. 
Published: April 2014

AbstractNative type II collagen is tolerogenic when given orally or i.p. to DBA/1J mice and induces autoimmune arthritis when given s.c. in CFA. The tolerogenic epitope is contained in cyanogen bromide fragment 11 (CB11) and is structurally mimicked by PGEQGPK within the platelet aggregation-associated protein (PAAP) on Streptococcus sanguis. To learn whether S. sanguis modulates transmucosally the Ag-specific development of autoimmune arthritis, DBA/1J pups were given live S. sanguis, CB11, or type II collagen intragastrically. Feeding S. sanguis at 6 days postpartum delayed the onset of arthritis, and reduced the rate, final severity, and percentage of affected limbs. Next, PAAP+ S. sanguis and type II collagen were tested for T cell cross-reactivity. T cells primed with the tolerogenic epitope of type II collagen proliferated more when incubated with PAAP+ S. sanguis than with PAAP− Streptococcus gordonii or type II collagen, suggesting an Ag-specific transmucosal tolerogenic effect. In neonatal mice, therefore, bacterial surface Ags that mimic self can transmucosally stimulate Ag-specific inhibitory T cells. In adult mice immunized with type II collagen, these Ag-specific inhibitory T cells manifest later as attenuated arthritis. The PAAP+ S. sanguis appear to activate adult memory, rather than naive, type II collagen-specific T cells, suggesting that systemic challenge with commensal self-mimicking microorganisms may perpetuate existing autoimmunity, but not initiate autorecognition.