bluuebunny/crossref_metadata_2025_split huggingface dataset:
Shift of C3 deposition from localization in the glomerulus into the tubulo-interstitial compartment in the absence of secreted IgM in immune complex glomerulonephritis
Authors: Vaculik C , Rüger B M , Yanagida G , Hollemann D , Soleiman A , Losert U M , Chen J , Fischer M B 
Published: July 2010

SummaryThe role of secretory IgM in protecting kidney tissue from immune complex glomerulonephritis induced by 4 mg horse spleen apoferritin and 0·05 mg lipopolysaccharide has been investigated in mutant mice in which B cells do not secrete IgM, but are capable of expressing surface IgM and IgD and secreting other Ig isotypes. Glomerular size, number of glomeruli per cross-section, glomerular cellularity and urine content of protein and creatinine was comparable in treated secreted IgM (sIgM)-deficient and wild-type mice. Assessment of urinary proteins by sodium dodecyl sulphate-polyacrylamide gel electrophoresis showed a 30 kDa low molecular weight protein in treated sIgM-deficient animals only, reflecting dysfunction of proximal tubules. A shift of bound C3 from glomeruli to the tubulo-interstitial compartment in sIgM-deficient mice also suggests tubulo-interstitial damage. In contrast, local C3 synthesis within the kidney tissue did not differ between the two treated groups. Apoptosis physiologically present to maintain kidney cell homeostasis was increased slightly in treated wild-type mice. These results indicate that secretory IgM can protect the tubulo-interstitial compartment from immune complex-induced damage without having an effect on the glomerulus.
Comparative therapeutic effects of orally administered 1,25-dihydroxyvitamin D3 and 1alpha-hydroxyvitamin D3 on type-1 diabetes in non-obese diabetic mice fed a normal-calcaemic diet
Authors: Driver J P , Foreman O , Mathieu C , Van Etten E , Serreze D V 
Published: July 2010

SummaryFrequent injections of the hormonal form of vitamin D3, 1,25 dihydroxyvitamin D3 (1,25D3) reportedly inhibits autoimmune type 1 diabetes (T1D) in non-obese diabetic (NOD) mice by correcting some of the abnormalities in antigen-presenting cells which contribute the development of pathogenic T cell responses. This route of administration greatly elevates the levels of these compounds in the bloodstream for hours after treatment, which requires mice to be fed diets formulated to contain much reduced levels of Ca to avoid the toxic effects of hypercalcaemia. In the current work, we demonstrate that feeding 1,25D3 or its synthetic precursor, 1alpha(OH) vitamin D3 (1alphaD3), as part of a T1D supportive chow diet containing normal levels of Ca, is an effective means of reducing the incidence of disease in NOD mice, but the doses required for protection elicited hypercalcaemia. However, T1D protection elicited by D3 analogue feeding appears, at least partially, to have an immunological basis, as splenic T cells from treated mice had a decreased capacity to adoptively transfer disease. Protection is associated with an increased proportion of T cells with CD4+ forkhead box P3+ regulatory phenotype within the islet infiltrate of treated animals. The 1alphaD3 precursor is converted rapidly to the active 1,25D3 isoform in vivo. However, feeding the 1alphaD3 analogue elicited stronger T1D protection than the 1,25D3 compound, but also induced more severe hypercalcaemia. In future, the dietary supplementation of novel low-calcaemic D3 analogues may enable their continuous delivery at levels that inhibit T1D development in susceptible humans consuming normal levels of Ca.
l-Ficolin binding and lectin pathway activation by acetylated low-density lipoprotein
Authors: Faro J , Chen Y , Jhaveri P , Oza P , Spear G T , Lint T F , Gewurz H 
Published: July 2010

Summary
l-Ficolin, like mannan-binding lectin (MBL), is a lectin pathway activator present in normal human plasma. Upon binding ligand, l-ficolin similarly initiates C4 cleavage via the serine protease MBL-associated serine protease-2 (MASP-2). We sought further insight into l-ficolin binding reactions and MASP-2 activation by passing plasma through GlcNAc-derivatized Sepharose. l-Ficolin bound in 1·0 M NaCl-ethylenediamine tetraacetic acid (EDTA), and remained bound in NaCl-free EDTA, while MASP-2 eluted in proenzyme form (∼20% yield, &gt; 40 000-fold purification). l-Ficolin was eluted with GlcNAc in 1·0 M NaCl (∼10% yield, &gt; 3000-fold purification), with trace amounts of C3, α2-macroglobulin and both native and activated MASP-2. These preparations were utilized to investigate l-ficolin reactivities with acetylated low-density lipoprotein (A-LDL) as a model ligand in albumin-free systems. l-Ficolin bound strongly to A-LDL in the absence as well as presence of calcium, including saline-EDTA, and was optimal in 1·0 M NaCl-EDTA, but binding failed to occur in EDTA in the absence of NaCl. The addition of l-ficolin to immobilized A-LDL resulted in activation of MASP-2 in unmodified but not ficolin-depleted plasma unless l-ficolin was restored. We conclude that A-LDL is a useful ligand for investigation of l-ficolin function; both binding and activation are optimally examined in systems free of albumin; and ligand binding in 1·0 M NaCl in EDTA can be useful in the isolation of l-ficolin and native MASP-2.
Preparing for first-in-man studies: the challenges for translational immunology post-TGN1412
Authors: Dayan C M , Wraith D C 
Published: July 2010

Summary
Current immunology research is generating many new approaches to immunotherapy. However, the recent disaster surrounding the testing of TGN1412, has unsettled regulators and the pharmaceutical industry regarding new immunotherapies and highlighted the complexities of conducting clinical trials with agents that target the immune system. Here we discuss the critical role for immunologists in ensuring that the development of new immunotherapies continues.
Basal lymphoid aggregates in ulcerative colitis colon: a site for regulatory T cell action
Authors: Sitohy B , Hammarström S , Danielsson Å , Hammarström M-L 
Published: July 2010

Summary
Regulatory T cells seem to play a central role in maintaining immune tolerance in the gut mucosa. Previously we have shown that interleukin (IL)-10 is produced at high levels in the inflamed colonic tissue of ulcerative colitis (UC) patients. The cellular source was CD4+ T cells, suggesting local activation of regulatory T cells. The present study was performed to determine whether the frequency of regulatory T cells is increased in UC colon and whether they are present in the basal lymphoid aggregates, the prominent microanatomical structure in UC colon. Colonic tissue specimens from UC and control patients were analysed for frequencies of lamina propria lymphocytes expressing the regulatory T cell markers forkhead box protein 3 (FoxP3), CD25 and glucocorticoid-induced tumour necrosis factor receptor family-related gene (GITR) as well as CD28, CD4 and CD3 by using marker specific reagents in immunomorphometry. Two-colour immunohistochemistry was used for detection of CD25/IL-10, FoxP3/IL-10 and CD25/FoxP3 double-positive cells. GITR+ and FoxP3+ cells were present in normal colon mucosa, although at a relatively low frequency, and were located preferentially within the solitary follicles. UC was associated with significantly increased frequencies of CD25+, GITR+ and FoxP3+ lamina propria lymphocytes both within the basal lymphoid aggregates and in the lamina propria outside. Many of the CD25+ cells co-expressed FoxP3 as well as IL-10, suggesting that these are indeed IL-10 secreting regulatory T cells, activated in an attempt to counteract the inflammation. Increased frequency of regulatory T cell subtypes seems insufficient to control the disease activity in UC.
T cell activation profiles in Kawasaki syndrome
Authors: Brogan P A , Shah V , Clarke L A , Dillon M J , Klein N 
Published: July 2010

SummarySuperantigens (SAgs) are potent stimulators of T cells bearing specific Vβ T cell receptors (TCR) and may play a role in the pathogenesis of Kawasaki syndrome (KS), although despite 15 years of intense study this area remains controversial. Because SAgs can cause Vβ restricted T cell activation in the absence of Vβ skewing the aims of this study were to describe a flow cytometric protocol to study both CD4 and CD8 Vβ repertoires, and CD69 expression across the CD4 and CD8 Vβ repertoire in children with KS. Sixteen children with KS were studied. There was no significant increase in overall peripheral blood CD4 or CD8 T cell activation as determined by CD69 expression. However, Vβ restricted CD4 and/or CD8 activation was observed in eight of 11 (72%) of the KS patients, a finding not observed in healthy controls. Thirteen of 16 (81%) of the KS patients had evidence of either Vβ skewing (particularly CD4 Vβ2 and Vβ5·1) and/or Vβ restricted activation. Three patients had Vβ restricted activation in the absence of skewing. We suggest that these preliminary observations highlight the many layers of complexity when considering T cell activation in KS, which could explain some of the conflicting studies regarding peripheral blood T cell activation and Vβ skewing. It is likely that in order to move forward with this debate a combination of detailed microbiological, immunological and molecular techniques applied to individual patients will be required ultimately to prove or refute the SAg hypothesis of KS.
Neurotrophins modulate monocyte chemotaxis without affecting macrophage function
Authors: Samah B , Porcheray F , Gras G 
Published: July 2010

SummaryNeurotrophins nerve growth factor (NGF), brain-derived growth factor (BDNF), neurotrophin-3 (NT-3) and neurotrophin-4 (NT-4) and their high-affinity tyrosine protein kinase receptor (Trk) family, TrkA, TrkB, TrkC, and low-affinity p75NTR receptor, are key molecules implicated in the development of the central nervous system. Increasing evidence suggests that they also have physiological and pathological roles outside the nervous system. In this study we examined the expression of neurotrophins and their receptors in human activated macrophages and to what extent neurotrophins themselves modulate macrophage activation, in a model of primary adult monocyte-derived macrophage. Our data indicate that macrophages express neurotrophin and neurotrophin receptor genes differentially, and respond to cell stimulation by specific inductions. Neurotrophins did not modify the antigen-presenting capacities of macrophages or their production of proinflammatory cytokines, but somehow skewed their activation phenotype. In contrast, NGF clearly increased CXCR-4 expression in macrophage and their chemotactic response to low CXCL-12 concentration. The differential effect of specific macrophage stimuli on neurotrophin expression, in particular NGF and NT-3, and the specific enhancement of CXCR-4 expression suggest that neurotrophins might participate in tissue-healing mechanisms that should be investigated further in vivo.
Naturally occurring Bruton's tyrosine kinase mutations have no dominant negative effect in an X-linked agammaglobulinaemia cellular model
Authors: Pérez de Diego R , López-Granados E , Rivera J , Ferreira A , Fontán G , Bravo J , García Rodríguez Ma C , Bolland S 
Published: July 2010

Summary
X-linked agammaglobulinaemia (XLA) is characterized by absence of mature B cells because of mutations in the Bruton's tyrosine kinase (Btk) gene. Btk-deficient early B cell precursors experience a block in their differentiation potentially reversible by the addition of an intact Btk gene. Btk expression was measured in 69 XLA patients with 47 different mutations and normal expression was detected in seven. We characterized these Btk mutant forms functionally by transfection into a lymphoma cell line that lacks endogenous Btk expression (Btk−/− DT40 cells) and analysed the calcium flux in response to B cell receptor stimulation. To test whether co-expression of a mutated form could compromise the function of the intact Btk transfection, studies in wild-type (WT) DT40 cells were also performed. Study reveals that none of the seven Btk mutants analysed was able to revert the absence of calcium mobilization upon IgM engagement in Btk−/− DT40 cells, as does intact Btk. In addition, calcium mobilization by anti-IgM stimulation in DT40 Btk+/+ cells was unaffected by co-expression with Btk mutants. These results suggest that gene addition would be feasible not only for patients with XLA and mutations that prevent Btk expression, but for those with expression of a mutant Btk.
Immune tolerance induction to enzyme-replacement therapy by co-administration of short-term, low-dose methotrexate in a murine Pompe disease model
Authors: Joseph A , Munroe K , Housman M , Garman R , Richards S 
Published: July 2010

SummaryClinical investigations of recombinant human acid α-glucosidase for the treatment of Pompe disease often reveal the appearance of therapy-specific antibodies. These antibodies could potentially interfere with recombinant human acid α-glucosidase efficacy and induce immunological consequences. Several immunosuppressive agents, including methotrexate, mycophenolate mofetil and cyclosporin A with azathioprine, were evaluated for their potential to induce immune tolerance to recombinant human acid α-glucosidase. Methotrexate was the only agent that reduced recombinant human acid α-glucosidase-specific antibody responses in acid α-glucosidase knock-out mice. A 3-week, low-dose methotrexate regimen controlled recombinant human acid α-glucosidase-specific antibody levels throughout 8 months of weekly recombinant human acid α-glucosidase treatment. The success of this methotrexate regimen appears to require methotrexate administration within the first 24 h of recombinant human acid α-glucosidase treatment. In an attempt to understand the benefit of methotrexate within the first day of recombinant human acid α-glucosidase administration, the immune response 24 h following intravenous recombinant human acid α-glucosidase treatment was investigated. A consistent expansion of peritoneal B1 B cells was observed. Control over this B1 B cell response may be part of the complex mechanism of action of methotrexate-induced immune tolerance.
Immunomodulatory effects of plasminogen activators on hepatic fibrogenesis
Authors: Higazi A A , El-Haj M , Melhem A , Horani A , Pappo O , Alvarez C E , Muhanna N , Friedman S L , Safadi R 
Published: July 2010

SummaryTissue-type plasminogen activators (tPA) and urokinase-type plasminogen activators (uPA) are involved in liver repair. We examined the potential immunomodulatory actions of uPA, tPA and uPA-receptor (uPAR) in carbon-tetrachloride-induced hepatic fibrosis in wild-type (WT), tPA−/−, uPA−/− and uPAR−/− mice. Carbon-tetrachloride treatment increased fibrosis in four groups but significantly less in three knock-out models. Serum cytokines and intrahepatic T cells elevated significantly following fibrosis process in WT animals but not in the knock-out groups. In culture, uPA increased lymphocyte proliferation significantly in WT and uPA−/− but not uPAR−/− animals. Following uPA exposure in vivo, there was CD8 predominance. To isolate uPA's effect on lymphocytes, WT mice were irradiated sublethally and then reconstituted with WT or uPA−/− lymphocytes. In these animals fibrosis was decreased and T cells were reduced in the uPA−/− recipients. Based on these data we postulate that plasminogen activators affect fibrosis in part by liver-specific activation of CD8 subsets that govern the fibrogenic activity of hepatic stellate cells.
Inhibition of casein kinase 2 enhances the death ligand- and natural kiler cell-induced hepatocellular carcinoma cell death
Authors: Kim H-R , Kim K , Lee K-H , Kim S J , Kim J 
Published: July 2010

SummaryRecent studies have shown that the inhibition of casein kinase 2 (CK2) sensitizes many cancer cells to Fas ligand- and tumour necrosis factor-related apoptosis-inducing ligand (TRAIL)-induced apoptosis. However, it has not been demonstrated directly whether CK2 inhibition can also enhance the cytotoxicity of natural killer (NK) cells, which actually use the death ligands to kill cancer cells in vivo. To address whether NK cell-mediated cancer cell death is affected by the inhibition of CK2, we first checked whether the death ligand-induced apoptosis of hepatocellular carcinoma cells (HCCs) and HeLa were affected by CK2 inhibition. We then investigated the effect of CK2 inhibition on NK cytotoxicity against HCCs and HeLa cells and its mechanistic features. Inhibition of CK2 by emodin increased the apoptotic cell death of HepG2, Hep3B and HeLa when the cancer cell lines were treated with a soluble form of recombinant TRAIL or an agonistic antibody of Fas. This phenomenon appeared to be correlated with the expression level of death receptors on the cancer cell surface. More interestingly, the inhibition of CK2 also greatly increased the NK cell-mediated cancer cell killing. The NK cytotoxicity against the cancer cells increased about twofold when the target cells were pretreated with a specific CK2 inhibitor, emodin or 4,5,6,7-tetrabromobenzotriazole. Furthermore, the increase of the NK cytotoxicity against cancer cells by CK2 inhibition was granule-independent and mediated possibly by the death ligands on the NK cell surface. This suggests that CK2 inhibitors could be used to enhance the cytotoxicity of NK cells and consequently increase host tumour immunity.
A novel, helminth-derived immunostimulant enhances human recall responses to hepatitis C virus and tetanus toxoid and is dependent on CD56+ cells for its action
Authors: MacDonald A J , Libri N A , Lustigman S , Barker S J , Whelan M A , Semper A E , Rosenberg W M 
Published: July 2010

SummaryWe have described previously an immunostimulant derived from Onchocerca volvulus, the helminth parasite that causes onchocerciasis. Recombinant O. volvulus activation-associated secreted protein-1 (rOv-ASP-1) was a potent adjuvant for antibody and cellular responses to protein, polypeptide and small peptide antigens. Our aims were to determine whether rOv-ASP-1 is immunostimulatory for human peripheral blood mononuclear cells (PBMC) and, if so, whether it could augment cellular responses against human pathogen antigens in vitro. Cytokines from rOv-ASP-1-stimulated human PBMC were measured by a fluorescence activated cell sorter-based multiplex assay. Recall responses of normal healthy donor (NHD) and chronic hepatitis C virus (c-HCV)-infected patient PBMC to tetanus toxoid (TT) or HCV core (HCVco) antigen, respectively, were measured by interferon-γ enzyme-linked immunospot assays. Interferon-γ was the predominant cytokine induced by rOv-ASP-1. 77·3% of NHD anti-TT and 88·9% of c-HCV anti-HCVco responses were enhanced by rOv-ASP-1. The immunostimulant effect was dependent upon contact between CD56+ and CD56– fractions of PBMC. We have described a helminth-derived protein that can act as an immunostimulant for human recall responses in vitro to TT and, perhaps more importantly, HCV antigens in patients with chronic HCV infection. Our longer-term goal would be to boost anti-viral responses in chronic infections such as HCV.
Involvement of innate immunity in the pathogenesis of intestinal Behçet's disease
Authors: Nara K , Kurokawa M S , Chiba S , Yoshikawa H , Tsukikawa S , Matsuda T , Suzuki N 
Published: July 2010

SummaryThe involvement of excessive T helper 1 (Th1) cell functions in the pathogenesis of Behçet's disease (BD) has been reported. We therefore studied Toll-like receptor (TLR)-expressing cells, which play important roles in innate immunity in patients with BD. Peripheral blood mononuclear cells (PBMC) of BD and healthy controls, and tissue specimens of intestinal BD and Crohn's disease (CD) were analysed for messenger RNA (mRNA) and protein expressions by reverse transcription–polymerase chain reaction and immunostaining respectively. PBMC of BD expressed TLR-2 and TLR-4 mRNA almost comparable with healthy controls. Intestinal lesions of BD expressed TLR-2 and TLR-4 mRNA consistently. In contrast, TLR-4 mRNA was expressed preferentially and TLR-2 mRNA was expressed less frequently in CD lesions. In intestinal samples of BD, TLR-2 and TLR-4 mRNA were detected in ileocaecal ulcer lesions, but not in unaffected sites of the same sample, indicating the association of the TLR expression with the disease manifestation of intestinal BD. TLR-2-expressing cells which were simultaneously cluster of distribution (CD)68-positive produced interleukin (IL)-12 in the lesions, indicating the participation of TLR-2-expressing cells in the Th1 skewed responses in vivo. As a possible ligand of TLR-2, in BD self-heat shock protein 60 was expressed in peripheral blood lymphocytes and intestinal tissues. Collectively, TLR-2-expressing cells as well as TLR-4-expressing cells accumulated in the intestinal lesions of BD. IL-12 produced by TLR-2-expressing cells may contribute to the induction of Th1-dominant immune responses in intestinal BD.
Varicella zoster virus glycoprotein E-specific CD4+ T cells show evidence of recent activation and effector differentiation, consistent with frequent exposure to replicative cycle antigens in healthy immune donors
Authors: Malavige G N , Jones L , Black A P , Ogg G S 
Published: July 2010

SummaryVaricella zoster viru (VZV)-specific T cell responses are believed to be vital in recovery from primary VZV infection and also in the prevention of viral reactivation. While glycoprotein E (gE) is the most abundant and one of the most immunogenic proteins of the virus, there are no data addressing potential T cell epitopes within gE, nor the phenotype of specific T cells. Using interferon gamma enzyme-linked immunospot assays and intracellular cytokine assays, we identified gE-specific immune responses in 20 adult healthy immune donors which were found to be dominated by the CD4+ subset of T cells. We characterized three immune dominant epitopes within gE restricted through DRB1*1501, DRB1*07 and DRB4*01, and used DRB1*1501 class II tetrameric complexes to determine the ex vivo frequency and phenotype of specific T cells. In healthy immune donors, the cells were largely positive for CCR7, CD28 and CD27, but expressed variable CD62L and low levels of cutaneous lymphocyte associated antigen with evidence of recent activation. In summary, we show that circulating gE-specific CD4+ T cells are detected at a relatively high frequency in healthy immune donors and show evidence of recent activation and mixed central and effector memory phenotype. These data would be compatible with frequent exposure to replicative cycle antigens in healthy donors and are consistent with a role for gE-specific CD4+ T cells in the control of viral replication.
Reduced arthritis in MIF deficient mice is associated with reduced T cell activation: down-regulation of ERK MAP kinase phosphorylation
Authors: Santos L L , Dacumos A , Yamana J , Sharma L , Morand E F 
Published: July 2010

SummaryMacrophage migration inhibitory factor (MIF) is a pleiotropic pro-inflammatory cytokine with many cellular targets in rheumatoid arthritis (RA). MIF has been reported to activate cells via mitogen-activated protein kinase and serine/threonine kinase (AKT or protein kinase B)-dependent signal transduction pathways. Its contribution to T cell activation and signalling in RA is not known. Using MIF −/− mice and a T cell-mediated model of RA, antigen-induced arthritis, we investigated the role of MIF in T cell activation and signalling. Arthritis severity was significantly reduced in MIF −/− mice compared with wildtype mice. This reduction was associated with decreased T cell activation parameters including footpad delayed type hypersensitivity, antigen-induced splenocyte proliferation and cytokine production. Splenocyte proliferation required extracellular signal-regulated kinase (ERK)1/2 phosphorylation, and decreased T cell activation in MIF −/− mice was associated with decreased phosphorylation of ERK1/2 but not AKT. Collectively, these data suggest that MIF promotes antigen-specific immune responses via regulation of ERK phosphorylation in T cells.