bluuebunny/crossref_metadata_2025 huggingface dataset:
Immunoregulatory factors in multiple sclerosis patients during and after pregnancy: relevance of natural killer cells
Authors:   The Finnish Multiple Sclerosis and Pregnancy Study Group, Airas L , Saraste M , Rinta S , Elovaara I , Huang Y-H , Wiendl H
Published: July 2010

Multiple sclerosis (MS) ameliorates typically during pregnancy but after the delivery the relapse rate often increases. Our study was conducted to understand the immunoregulatory mechanisms accompanying this phenomenon. MS patients were followed-up prospectively during pregnancy and 6 months postpartum, with immunological characterization of the peripheral blood. Groups of age- and parity-matched healthy pregnant women, and age- and sex-matched non-pregnant women and non-pregnant MS patients were studied as controls. In our patient cohort, the annualized relapse rate was 1·0 ± 1·0 relapses/woman/year (mean ± standard deviation) during the year before pregnancy, but dropped to 0·2 ± 0·9 during the third trimester (P = 0·02). After the delivery the relapse rate increased again to 1·4 ± 1·9 (1–3 months postpartum versus third trimester P = 0·003). While percentages of peripheral blood CD3, CD4, CD8 and CD19 immune cell subsets were unchanged over the observation period, reduced disease activity during the last trimester was associated with a significant increase in the percentage of circulating CD56bright natural killer (NK) cells. Simultaneously, the proportion of circulating CD56dim NK cells was clearly reduced. No alteration was noted in CD4+ CD25high forkhead box P3+ regulatory T cells. Production of interferon-gamma by peripheral blood lymphocytes was down-regulated significantly during pregnancy in comparison to the postpartum period, resulting in an increased T helper type 2 (Th2) : Th1 ratio during pregnancy. In conclusion, pregnant state in MS patients is characterized by an increase in the percentage of CD56bright NK cells and by enhanced Th2 type cytokine secretion. Our findings suggest a potential role for CD56bright regulatory NK cells in the control of autoimmune inflammation during pregnancy in MS.
High serum YKL-40 level in a cohort of octogenarians is associated with increased risk of all-cause mortality
Authors: Johansen J S , Pedersen A N , Schroll M , Jørgensen T , Pedersen B K , Bruunsgaard H
Published: July 2010

YKL-40 is secreted by macrophages, neutrophils, chondrocytes, endothelial-, vascular smooth muscle- and cancer cells. Interleukin (IL)-6 stimulates YKL-40 production in human in vivo studies. High serum YKL-40 is associated with poor prognosis in patients with inflammatory diseases and cancer. We studied whether serum YKL-40 was associated with systemic low-level inflammation, an immune risk phenotype, and mortality in relatively healthy 80-year old humans. Serum YKL-40, IL-6 and tumour necrosis factor (TNF)-α were measured by enzyme-linked immunosorbent assays (ELISAs) in octogenarians (n = 151) and serum YKL-40 in 18–30-year-olds (n = 89). Fifty-one of the octogenarians died during the 6-year follow-up. Serum YKL-40 in octogenarians was higher compared to the level in young people (median 116 versus 31 μg/l, P < 0·0005). Serum YKL-40 correlated with serum IL-6 in elderly women (Spearman's rho = 0·30, P = 0·009) and men (rho = 0·25, P = 0·003), but only with serum TNF-α (rho = 0·23, P = 0·05) and C-reactive protein (CRP) (rho = 0·57, P < 0·0005) among the elderly women. In addition, high serum level of YKL-40 was associated with a low CD4 : CD8 cell ratio. Univariate analysis of serum YKL-40 (logarithmically transformed and divided by tertiles) showed significant association with all-cause mortality [tertile 3: hazard ratio (HR) = 2·38, 95% confidence interval (CI): 1·19–4·78, P = 0·02]. The effect persisted after adjusting for potential confounders (sex, smoking, body mass index, chronic disease and anti-inflammatory medicine). These results suggest that serum YKL-40 is a prognostic and sensitive biomarker of all-cause mortality in octogenarians.
Up-regulation of the phosphoinositide 3-kinase pathway in human lamina propria T lymphocytes
Authors: Braunstein J , Autschbach F , Giese T , Lasitschka F , Heidtmann A , Sido B , Funke B , Reiser C , Schröder A J , Nebl G , Samstag Y , Meuer S C
Published: July 2010

Human intestinal lamina propria T lymphocytes (LPT), when investigated ex vivo, exhibit functional properties profoundly different from those of peripheral blood T lymphocytes (PBT). One prominent feature represents their enhanced sensitivity to CD2 stimulation when compared to PBT. Given that LPT are hyporesponsive to T cell receptor (TCR)/CD3 stimulation, an alternative activation mode, as mimicked by CD2 triggering in vitro, may be functional in mucosal inflammation in vivo. This study provides insight into signalling events associated with the high CD2 responsiveness of LPT. When compared to PBT, LPT show an increased activation of the phosphoinositide 3/protein kinase B/glycogen synthase kinase 3β (PI3-kinase/AKT/GSK-3β) pathway in response to CD2 stimulation. Evidence is provided that up-regulation of this pathway contributes to the enhanced CD2-induced cytokine production in LPT. Given the importance of TCR-independent stimulation for the initiation of intestinal immune responses analysis of signalling pathways induced by ‘co-stimulatory’ receptors may provide valuable information for therapeutic drug design.
Leptin promotes cell survival and activates Jurkat T lymphocytes by stimulation of mitogen-activated protein kinase
Authors: Fernández-Riejos P , Goberna R , Sánchez-Margalet V
Published: July 2010

Leptin (Ob) is a non-glycosylated peptide hormone that regulates energy homeostasis centrally, but also has systemic effects including the regulation of the immune function. We have reported previously that leptin activates human peripheral blood lymphocytes co-stimulated with phytohaemagglutinin (PHA) (4 μg/ml), which prevented the employment of pharmacological inhibitors of signalling pathways. In the present study, we used Jurkat T cells that responded to leptin with minimal PHA co-stimulation (0·25 μg/ml). The long isoform of leptin receptor is expressed on Jurkat T cells and upon leptin stimulation, the expression of early activation marker CD69 increases in a dose-dependent manner (0·1–10 nM). We have also found that leptin activates receptor-associated kinases of the Janus family-signal transucers and activators of transcription (JAK-STAT), mitogen-activated protein kinase (MAPK) and phosphatidylinositol 3 kinase (PI3K) signalling pathways. Moreover, we sought to study the possible effect of leptin on cell survival and apoptosis of Jurkat T cells by culture in serum-free conditions. We have assayed the early phases of apoptosis by flow cytometric detection of fluorescein isothiocyanate (FITC)-labelled annexin V simultaneously with dye exclusion of propidium iodide (PI). As well, we have assayed the activation level of caspase-3 by inmunoblot with a specific antibody that recognizes active caspase-3. We have found that leptin inhibits the apoptotic process dose-dependently. By using pharmacological inhibitors, we have found that the stimulatory and anti-apoptotic effects of leptin in Jurkat T cells are dependent on MAPK activation, rather than the PI3K pathway, providing new data regarding the mechanism of action of leptin in T cells, which may be useful to understand more clearly the association between nutritional status and the immune function.
Association of TNF polymorphisms with sarcoidosis, its prognosis and tumour necrosis factor (TNF)-α levels in Asian Indians
Authors: Sharma S , Ghosh B , Sharma S K
Published: July 2010

Tumour necrosis factor (TNF)-α, an important proinflammatory cytokine, has been implicated in the pathogenesis of sarcoidosis, a multi-systemic granulomatous disorder of unknown aetiology. Here, we report for the first time the association of TNF haplotypes and genotypes with sarcoidosis and its prognosis in the Indian population. Five potentially functional promoter polymorphisms in the TNFA gene and a LTA_NcoI polymorphism (+252 position) of the LTA gene were genotyped in a clinically well-defined cohort of North-Indian patients with sarcoidosis (n = 96) and their regional controls (n = 155). Serum TNF-α (sTNF-α) and serum angiotensin converting enzyme (SACE) levels were measured and correlated with genotypes and haplotypes. The TNFA_-1031 and TNFA_-863 polymorphisms were identified as markers for disease onset (FET P = 0·006 and 0·042 for TNFA_-1031 and TNFA_-863, respectively). Additionally, the allele A of LTA_NcoI polymorphism was shown to be prevalent in the ‘no treatment’ group (FET P = 0·005), while the G allele was associated with frequent relapses on drug withdrawal (P = 0·057). Furthermore, the TNFA-308G>A and the TNFA-238G>A polymorphisms were found to influence sTNF-α (P = 0·054 and 0·0005, respectively) and SACE levels (P = 0·0017 and 0·056, respectively). The haplotype frequencies were significantly different in the patients and the controls (P = 0·0067). The haplotype GTCCGG was identified as the major risk/susceptibility haplotype (P = 0·003) and was associated with increased SACE levels in the patient population. In conclusion, our study suggests an association of TNF polymorphisms with sarcoidosis.
Multiple-antigen immunization of chickens facilitates the generation of recombinant antibodies to autoantigens
Authors: Hof D , Hoeke M O , Raats J M H
Published: July 2010

Antibody phage display is a powerful tool for the generation of monoclonal antibodies against virtually any given antigen. Chickens are phylogenetically more distant from humans compared to other laboratory animals, such as mice and rats. Therefore, the use of chickens is especially beneficial when generating recombinant antibodies against human autoantigens, which are often highly conserved among mammals. Another advantage of using chickens in antibody phage display is that the preparation of single chain variable fragment (scFv) antibody libraries is faster and easier compared to preparing such libraries from other species, as only two primer sets are needed for amplification of the chicken variable heavy chain (VH) and variable light chain (VL) genes. In the present study we explored the possibility to immunize chickens with antigen cocktails for the generation of recombinant antibody fragments directed to a range of human autoantigens. Two pairs of chickens were immunized with two cocktails of seven recombinant autoantigenic proteins, libraries were prepared and panned on the individual proteins. The polyclonal chicken sera reacted strongly with most of the antigens used for immunization. By creating and screening single-chain variable fragment antibody phage display libraries, recombinant monoclonal antibody fragments were isolated successfully against the autoantigens annexin XI, centromere protein B, heat shock protein B3, DNA topoisomerase I, histidyl tRNA synthetase, Ro52, Ro60, Rpp30 and U1A. In conclusion, the immunization of only four chickens with two distinct pools of a total of 14 autoantigenic proteins allowed the isolation of scFvs against nine of these antigens.
Treatment with glutamine is associated with down-regulation of Toll-like receptor-4 and myeloid differentiation factor 88 expression and decrease in intestinal mucosal injury caused by lipopolysaccharide endotoxaemia in a rat
Authors: Kessel A , Toubi E , Pavlotzky E , Mogilner J , Coran A G , Lurie M , Karry R , Sukhotnik I
Published: July 2010

Recent evidence suggests that lipopolysaccharide (LPS) endotoxaemia in a rat causes significant mucosal injury. Our objective was to determine the effects of glutamine (Gln) on Toll-like receptor 4 (TLR-4), myeloid differentiation factor 88 (Myd88) and tumour necrosis factor (TNF)-α receptor-associated factor 6 (TRAF6) expression in intestinal mucosa following LPS endotoxaemia in a rat. For this purpose, male Sprague–Dawley rats were assigned randomly to one of three experimental groups of 10 rats each: (i) control rats underwent intraperitoneal (i.p.) injection of sterile saline once a day; (ii) rats were treated with LPS given i.p. once a day at a dose of 10 mg/kg for 48 h (two doses); and (iii) rats were pretreated with oral Gln given in drinking water (2%) 48 h before and following injection of LPS. Intestinal mucosal parameters, enterocyte proliferation and apoptosis were determined at death. TLR-4 and MyD88 mRNA expression was measured with reverse transcription–polymerase chain reaction (RT–PCR). TLR-4 and MyD88 protein expression were analysed by Western immunoblotting. We observed a statistically significant (P < 0·05) decrease in mucosal weight, mucosal DNA and enterocyte proliferation and a significant increase in enterocyte apoptosis in rat intestine, following LPS administration. These changes were attenuated significantly by dietary Gln. Expression of TLR-4, MyD88 and TRAF6 mRNA in the mucosal ileum was significantly higher in LPS rats versus control rats (P = 0·0006, P = 0·0015, P = 0·03, respectively) as well as TLR-4 and MyD88 protein expression. The administration of Gln reduced significantly the expression of TLR-4, MyD88 and TRAF6 (P = 0·023, P = 0·014, P = 0·035, respectively) mRNA as well as TLR-4 and MyD88 protein expression in ileum compared to LPS animals. We did not find a significant change in the expression of TLR-4, MyD88 or TRAF6 in the jejunum of different groups. We conclude that treatment with Gln was associated with down-regulation of TLR-4, MyD88 and TRAF6 expression and concomitant decrease in intestinal mucosal injury caused by LPS endotoxaemia in a rat.
BDCA-1+, BDCA-2+ and BDCA-3+ dendritic cells in early human pregnancy decidua
Authors: Ban Y-L , Kong B-H , Qu X , Yang Q-F , Ma Y-Y
Published: July 2010

Dendritic cells (DCs) can acquire unique features or phenotypes in different tissue microenvironments and decide whether immunity or tolerance develops. DCs observed within the decidua have been implicated in pregnancy maintenance. However, the precise distribution of decidual DC subsets and their phenotypic characteristics are largely unknown. Using flow cytometry, we identified three DC subsets in normal human first-trimester decidua: BDCA-1+ CD19- CD14- myeloid DC type 1 (MDC1), BDCA-3+ CD14- myeloid DC type 2 (MDC2) and BDCA-2+ CD123+ plasmacytoid DC (PDC). The percentage of MDC1 to mononuclear cells in the decidua was similar to that in the peripheral blood controls. The percentage of MDC2 in the decidua was significantly higher than that in the peripheral blood controls, whereas the percentage of PDC was significantly lower. Both MDC1 and MDC2 subsets expressed human leucocyte antigen D-related, CD86 and CD80 at low levels, suggesting a characteristic of immature myeloid DCs. Immunoglobulin-like transcript 3, suggested to be involved in immune tolerance induction, was also expressed on decidual MDC1 and MDC2 subsets. In addition, as gestational age increased from 6 to 9 weeks, the numbers of MDC1 decreased but MDC2 increased significantly. This is the first study to demonstrate the presence of three previously unidentified BDCA-1+, BDCA-3+ and BDCA-2+ DC subsets in human decidua, these decidual DCs might play important role in the maintenance of pregnancy.
Elevated serum decoy receptor 3 with enhanced T cell activation in systemic lupus erythematosus
Authors: Lee C-S , Hu C-Y , Tsai H-F , Wu C-S , Hsieh S-L , Liu L-C , Hsu P-N
Published: July 2010

Decoy receptor 3 (DcR3/TR6) is a decoy receptor for the Fas ligand (FasL) and can inhibit FasL-induced apoptosis. It has been reported recently that DcR3 can induce T cell activation via co-stimulation of T cells, suggesting that DcR3 may be involved in the pathophysiology of autoimmune diseases. This study aims to analyse the serum DcR3 in patients with systemic lupus erythematosus (SLE) and to investigate the role of DcR3 in the pathogenesis of SLE. Significantly elevated serum DcR3 was observed in SLE patients, and the mean serum DcR3 level was significantly higher for those with active disease [SLE disease activity index (SLEDAI) ≥ 10] compared with that in patients with inactive disease (SLEDAI < 10). In addition to reducing activation-induced cell death in activated T cells via neutralization of the FasL, soluble DcR3–Fc enhanced T cell proliferation and increased interleukin-2 and interferon-γ production via co-stimulation of T cells. Moreover, enhanced T cell reactivity to DcR3-induced co-stimulation was demonstrated in lymphocytes from patients with SLE, suggesting the elevated serum DcR3 may associate with enhanced T cell activation in vivo. These findings are the first to demonstrate that serum DcR3 concentrations are increased in SLE patients, and this may imply a possible role of DcR3 in the pathogenesis of SLE via enhanced T cell hyperreactivity and reduced apoptosis in activated T cells.
Natural killer cells are required for accelerated type 1 diabetes driven by interferon-β
Authors: Alba A , Planas R , Clemente X , Carrillo J , Ampudia R , Puertas M-C , Pastor X , Tolosa E , Pujol-Borrell R , Verdaguer J , Vives-Pi M
Published: July 2010

The destruction of β cells by the islet infiltrating lymphocytes causes type 1 diabetes. Transgenic mice models expressing interferon (IFN)-β in β cells, in the non-obese diabetic (NOD) strain and in a diabetes-free, major histocompatibility complex-matched, homologous strain, the non-obese resistant (NOR) mice, developed accelerated type 1 diabetes after 3 weeks of age. Our aim was to determine if natural killer (NK) cells could affect the acceleration of the disease. We determined the amount of NK cells in the pancreas, spleen and lymph nodes from NOD rat insulin promoter (RIP)-IFN-β mice. Pancreatic cytokines were assessed by quantitative real-time polymerase chain reaction and protein arrays. To confirm the relevance of NK cells in the acceleration of autoimmune diabetes this subset was depleted with anti-asialo GM1 antibodies. An increase of intrapancreatic NK cells characterized the accelerated onset of diabetes both in NOD and NOR RIP-IFN-β transgenic models. Cytokines involved in NK function and migration were found to be hyperexpressed in the pancreas from accelerated diabetic mice. Interestingly, the depletion of NK cells in vivo abolished completely the acceleration of diabetes. NK cells connect innate to adaptive immunity and might play a role in autoimmunity. We report here that NK cells are required critically in the pancreas for accelerated diabetes. This model links inflammation to acceleration of β cell-specific autoimmunity mediated by NK cells.
Interleukin-21 stimulates antigen uptake, protease activity, survival and induction of CD4+ T cell proliferation by murine macrophages
Authors: Rückert R , Bulfone-Paus S , Brandt K
Published: July 2010

Interleukin (IL)-21 is a T cell-derived cytokine which uses a heterodimeric receptor, composed of the common γ-chain (CD132) and an IL-21Rα-chain. IL-21 activates lymphoid T and B cells, modulates antibody production but also suppresses maturation of myeloid dendritic cells; however, its role in the differentiation and function of other myeloid cells remains less clear. In this study we analysed IL-21/IL-21Rα effects on macrophage (MΦ) differentiation and function. MΦ could be generated readily from bone marrow with MΦ–colony-stimulating factor in the presence of IL-21 (designated IL-21MΦ) or from IL-21Rα–/– mice. IL-21Rα–/– mice had normal MΦ numbers, suggesting a non-essential role of both IL-21 and the IL-21Rα for MΦ generation. We could demonstrate that mature MΦ express the IL-21Rα and the common γ-chain. However, short-term IL-21 stimulation did not enhance MΦ proliferation but induced anti-apoptotic cell-cycle regulators p21waf1/p27Kip1 and expression of suppressors of cytokine signalling (SOCS)2/SOCS3. Moreover, IL-21 enhanced phagocytosis by MΦ via IL-21Rα signalling and supports protease activity and matrix metalloproteinase 12 expression. Stimulating MΦ with IL-21 enhanced their capacity to induce antigen-specific CD4+ T cell proliferation in dependence from the IL-21Rα, which was not the case for CD8+ T cells. Taken together, IL-21 plays a previously unrecognized role in modulating innate and acquired effector mechanisms of murine MΦ by linking these different functions to support CD4+ T cell-mediated immune responses.
AvirulantSalmonella typhimuriumstrains prevent food allergy in mice
Authors: Eigenmann P A , Asigbetse K E , Frossard C P
Published: July 2010

Oral tolerance to foods can be regulated by microorganisms in the gut lumen. We hypothesized that pretreatment with avirulent Salmonella typhimurium strains could prevent food allergy in mice. Mice were administered S. typhimurium PhoPc (STPhoPc) or S. typhimurium AroA prior to oral sensitization to β-lactoglobulin in the presence of cholera toxin. An oral antigen challenge after sensitization assessed antigen-induced anaphylaxis. Antigen-specific antibody titres were measured by enzyme-linked immunosorbent assay in the serum and enzyme-linked immunospot (ELISPOT) in the spleen, and cytokine-secreting cells were measured by ELISPOT in the Peyer's patches, lamina propria and epithelium cells. We showed first that S. typhimurium could up-regulate interleukin (IL)-12 and IL-10 secretion by gut T cells. Mice pretreated with STPhoPc had decreased anaphylaxis upon challenge, along with decreased immumoglobulin G1 (IgG1) and IgE antibody titres. Mice having received S. typhimurium AroA had partly decreased anaphylaxis as well as decreased serum IgG1 antibody titres in the serum, and increased serum IgA antibody titres. Antibody titres could be correlated with increased numbers of spleen and Peyer's patches antibody-producing cells. STPhoPc-treated mice showed significantly decreased anaphylaxis when compared with the control mice, while S. typhimurium AroA-pretreated mice had a similar immune response together with increased secretory IgA titres. Our experiments have proved a potential immunomodulatory protective effect by two avirulent S. typhimurium strains.
BeWo trophoblast cell susceptibility toToxoplasma gondiiis increased by interferon-γ, interleukin-10 and transforming growth factor-β1
Authors: Barbosa B F , Silva D A O , Costa I N , Mineo J R , Ferro E A V
Published: July 2010

The present study aimed to investigate BeWo trophoblast cell susceptibility to Toxoplasma gondii infection under stimulation with anti-inflammatory cytokines in comparison with HeLa cells. Both cell types were submitted to different treatments with recombinant cytokines [interleukin (IL)-10 and transforming growth factor (TGF)-β1] or the respective antibodies (anti-IL-10 and anti-TGF-β) before and after T. gondii infection. The effect of interferon (IFN)-γ was also assessed alone or in combination with anti-inflammatory cytokines or the respective antibodies after the parasite infection. Cells were fixed, stained and parasites quantified under light microscopy to evaluate intracellular replication (mean number of parasites per cell in 100 infected cells) and infection index (percentage of infected cells per 100 examined cells). In contrast with HeLa cells, treatments with IL-10 or TGF-β1 induced a considerable augmentation in both T. gondii intracellular replication and invasion into BeWo cells. In addition, treatment with IFN-γ alone or associated with IL-10 or TGF-β1 increased the same parameters in BeWo cells, whereas the opposite effect was observed in HeLa cells. When endogenous IL-10 or TGF-β was blocked, both BeWo and HeLa cells were able to control the parasite infection only in the presence of IFN-γ. Together, these results indicate that the higher susceptibility of BeWo cells to T. gondii may be due to immunomodulation mechanisms, suggesting that the role of trophoblast cells in maintaining a placental microenvironment favourable to pregnancy may facilitate the infection into the placental tissues.
Determinants of natural immunity against tuberculosis in an endemic setting: factors operating at the level of macrophage–Mycobacterium tuberculosisinteraction
Authors: Gaikwad A N , Sinha Sudhir
Published: July 2010

We aimed to delineate factors operating at the interface of macrophage–mycobacterium interaction which could determine the fate of a ‘subclinical’ infection in healthy people of a tuberculosis-endemic region. Ten study subjects (blood donors) were classified as ‘high’ or ‘low’ responders based on the ability of their monocyte-derived macrophages to restrict or promote an infection with Mycobacterium tuberculosis. Bacterial multiplication between days 4 and 8 in high responder macrophages was significantly lower (P < 0·02) than low responders. All donor sera were positive for antibodies against cell-membrane antigens of M. tuberculosis and bacilli opsonized with heat-inactivated sera were coated with IgG. In low responder macrophages, multiplication of opsonized bacilli was significantly less (P < 0·04) than that of unopsonized bacilli. The levels of tumour necrosis factor (TNF)-α and interleukin (IL)-12 produced by infected high responder macrophages was significantly higher (P < 0·05) than low responders. However, infection with opsonized bacilli enhanced the production of IL-12 in low responders to its level in high responders. The antibody level against membrane antigens was also significantly higher (P < 0·05) in high responders, although the antigens recognized by two categories of sera were not remarkably different. Production of certain other cytokines (IL-1β, IL-4, IL-6 and IL-10) or reactive oxygen species (H2O2 and NO) by macrophages of high and low responders did not differ significantly. The study highlights the heterogeneity of Indian subjects with respect to their capability in handling subclinical infection with M. tuberculosis and the prominent role that TNF-α, opsonizing antibodies and, to a certain extent, IL-12 may play in containing it.
Intracellular adhesion molecule-1 up-regulation on thyrocytes by iodine of non-obese diabetic.H2h4 mice is reactive oxygen species-dependent
Authors: Sharma R , Traore K , Trush M A , Rose N R , Burek C Lynne
Published: July 2010

Intracellular adhesion molecule-1 (ICAM-1) expression on the thyroid follicular cells of non-obese diabetic (NOD).H2h4 mice is enhanced by iodide treatment, which correlates with autoimmune thyroid disease in genetically susceptible NOD.H2h4 mice. The current study examines the mechanism of iodine-enhanced up-regulation of ICAM-1 on the surface of thyroid cells. We hypothesized that the up-regulation of ICAM-1 is due to a transient increase in production of reactive oxygen species (ROS). ROS may initiate signalling of the ICAM-1 gene promoter, enhancing up-regulated ICAM-1 protein on the cell surface. Single-cell suspensions of thyroid follicular cells from thyroiditis-susceptible NOD.H2h4 or non-susceptible BALB/c mice were treated in vitro with sodium iodide. Extracellular and intracellular ROS were assessed by luminol-derived chemiluminescence and flow cytometry assays respectively. Our results demonstrate that thyroid follicular cells of NOD.H2h4 generate higher levels of ROS compared with cells from non-susceptible strains of mice. Expression of a subunit protein of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase, p67phox, was analysed by Western blot immunoassay. A constitutive expression of the p67phox subunit protein was observed in NOD.H2h4 mice prior to iodine treatment. No such expression was found in BALB/c mice. Treatment of NOD.H2h4 thyroid cells with diphenyleneiodium, an inhibitor of NADPH oxidase, reduced generation of ROS and of ICAM-1 protein expression. Thus, thyrocytes from NOD.H2h4 mice produce enhanced levels of ROS that may be mediated by NADPH oxidase. Consequently, in NOD.H2h4 mice the ROS-induced signal for ICAM-1 up-regulation may contribute to mononuclear cellular infiltration of the thyroid gland and the progression of autoimmune thyroid disease.
Oestrogen exhibits type II collagen protective effects and attenuates collagen-induced arthritis in rats
Authors: Nielsen R H , Christiansen C , Stolina M , Karsdal M A
Published: July 2010

As anti-inflammatory treatments used in rheumatoid arthritis, such as glucocorticoids, often result in secondary detrimental effects on bone health, the objective of this study was to investigate the effects of oestrogen therapy (ET) on the development and activity of collagen-induced arthritis (CIA) in rats, with a focus on assessment of chondroprotective effects using biomarkers of type II collagen degradation. Forty female Lewis rats were allocated into four intervention groups: (i) control + vehicle; (ii) CIA + vehicle; (iii) CIA + ET; and (iv) CIA + prednisolone. During the 28-day intervention period we monitored body weight, time-point of disease onset, incidence of manifest disease and paw volume. Levels of the type II collagen degradation marker (CTX-II) were measured in serum. At euthanasia, hind paws were isolated, extracted for proteins and measured for the concentration of CTX-II. Matrix metalloproteinase (MMP) activity was evaluated using gelatinase zymography. Oestrogen treatment delayed the time-point of disease onset and reduced the incidence and degree of manifest immunoarthritis significantly, assessed by macroscopic evaluation of hind paw inflammation and paw volume. Measures of serum or tissue levels of CTX-II showed significantly reduced type II collagen degradation elicited by oestrogen treatment. In alignment, a decreased activity of MMP-2 and MMP-9 was found in the paw protein extracts. We have demonstrated that the anti-inflammatory effect of ET is linked to chondroprotective effects in an animal model of systemic immunoarthritis. As ET has positive rather than negative effects on bone health in contrast to prednisolone, these observations may be important for potential combination therapy.
Possible association between thyroid autoimmunity and Menière's disease
Authors: Fattori B , Nacci A , Dardano A , Dallan I , Grosso M , Traino C , Mancini V , Ursino F , Monzani F
Published: July 2010

Various aetiopathological mechanisms have been postulated to be at the root of Menière's disease (MD), and some data suggest that there may be also an underlying autoimmune factor. In fact, Menière patients manifest certain characteristics that are typical of autoimmune involvement association of particular human leucocyte antigen haplotypes, the presence of antibodies against internal ear antigens. In this study, we evaluated the association between thyroid autoimmunity and MD in a non-selected group of patients. We recruited 50 consecutive MD patients and two groups as controls: group A, 82 healthy volunteers; and group B, 50 subjects suffering from acute unilateral peripheral vestibulopathy. All subjects were submitted to instrumental assessment of cochlear–vestibular function and analysis of thyroid-stimulating hormone (TSH), free triiodothyronine, free thyroxine, anti-TSH receptor antibody (TR-Ab), anti-thyroperoxidase antibody (TPO-Ab) and anti-thyroglobulin antibody (Tg-Ab) in the blood. The prevalence of autoimmune thyroiditis in group B [6/50 (12%); 66·7% TPO-Ab and 33·3% Tg-Ab] was superimposable with the healthy controls [6/82 (7%); 66·7% TPO-Ab and 33·3% Tg-Ab]. In contrast, 38% of the MD patients (P = 0·0001 versus group A and group B) had significant autoantibody levels (68·4% TPO-Ab; 15·8% TPO-Ab + TR-Ab; 10·5% Tg-Ab; 5·2% TPO-Ab + Tg-Ab). Furthermore, 14% of the MD patients were hyperthyroid under l-thyroxine therapy, while no dysfunction was seen in the control groups. Overall, our data demonstrate a significant association between MD and thyroid autoimmunity, which suggests that an autoimmune factor is involved in the aetiopathogenesis of this disease. These findings suggest that it should be useful to submit MD patients to multi-disciplinary clinical investigation.
Coeliac disease-specific autoantibodies targeted against transglutaminase 2 disturb angiogenesis
Authors: Myrsky E , Kaukinen K , Syrjänen M , Korponay-Szabó I R , Mäki M , Lindfors K
Published: July 2010

Coeliac disease is characterized by immunoglobulin-A (IgA)-class autoantibodies targeted against transglutaminase 2 (TG2), a multi-functional protein also with a role in angiogenesis. These antibodies are present in patient serum but are also found bound to TG2 below the epithelial basement membrane and around capillaries in the small intestinal mucosa. Based on these facts and the information that the mucosal vasculature of coeliac patients on a gluten-containing diet is disorganized, we studied whether the coeliac disease-specific autoantibodies targeted against TG2 would disturb angiogenesis. The effects of coeliac disease-specific autoantibodies on in vitro angiogenesis were studied in angiogenic cell cultures. The binding of the antibodies to cells, endothelial sprouting, migration of both endothelial and vascular mesenchymal cells, the integrity of the actin cytoskeleton in both cell types and the differentiation of vascular mesenchymal cells were recorded. In vitro, IgA derived from coeliac disease patients on a gluten-containing diet binds to surface TG2 on endothelial and vascular mesenchymal cells and this binding can be inhibited by the removal of TG2. In addition, coeliac disease-specific autoantibodies targeting TG2 disturb several steps of angiogenesis: endothelial sprouting and the migration of both endothelial and vascular mesenchymal cells. Furthermore, the autoantibodies cause disorganization of the actin cytoskeleton in both capillary cell types that account most probably for the defective cellular migration. We conclude that coeliac disease-specific autoantibodies recognizing TG2 inhibit angiogenesis in vitro. This disturbance of the angiogenic process could lead in vivo to the disruption of the mucosal vasculature seen in coeliac disease patients on a gluten-containing diet.
The mechanism of development of acute lung injury in lethal endotoxic shock using α-galactosylceramide sensitization
Authors: Tumurkhuu G , Koide N , Dagvadorj J , Morikawa A , Hassan F , Islam S , Naiki Y , Mori I , Yoshida T , Yokochi T
Published: July 2010

The mechanism underlying acute lung injury in lethal endotoxic shock induced by administration of lipopolysaccharide (LPS) into α-galactosylceramide (α-GalCer)-sensitized mice was studied. Sensitization with α-GalCer resulted in the increase of natural killer T (NK T) cells and the production of interferon (IFN)-γ in the lung. The IFN-γ that was produced induced expression of adhesion molecules, especially vascular cell adhesion molecule-1 (VCAM-1), on vascular endothelial cells in the lung. Anti-IFN-γ antibody inhibited significantly the VCAM-1 expression in α-GalCer-sensitized mice. Very late activating antigen-4-positive cells, as the counterpart of VCAM-1, accumulated in the lung. Anti-VCAM-1 antibody prevented LPS-mediated lethal shock in α-GalCer-sensitized mice. The administration of LPS into α-GalCer-sensitized mice caused local production of excessive proinflammatory mediators, such as tumour necrosis factor (TNF)-α, interleukin (IL)-1β, IL-6 and nitric oxide. LPS caused microvascular leakage of proteins and cells into bronchoalveolar lavage fluid. Taken together, sensitization with α-GalCer was suggested to induce the expression of VCAM-1 via IFN-γ produced by NK T cells and recruit a number of inflammatory cells into the lung. Further, LPS was suggested to lead to the production of excessive proinflammatory mediators, the elevation of pulmonary permeability and cell death. The putative mechanism of acute lung injury in LPS-mediated lethal shock using α-GalCer sensitization is discussed.
Recombinant early secreted antigen target 6 protein as a skin test antigen for the specific detection of Mycobacterium tuberculosis infection
Authors: Wu X , Zhang L , Zhang J , Zhang C , Zhu L , Shi Y
Published: July 2010

Although the delayed-type hypersensitivity skin test reaction to tuberculin purified protein derivative (PPD) is used worldwide for tuberculosis (TB) detection, it is incapable of distinguishing Mycobacterium tuberculosis (MTB) infection from bacille Calmette–Guérin (BCG) vaccination or infection with non-tuberculous Mycobacteria. As a result, there is an urgent need for a more specific diagnostic tool for TB. This study reports the skin reactions of guinea pigs and human volunteers to recombinant early secreted antigen target 6 (rESAT6), a secretory protein found only in MTB, M. bovis and few other mycobacterial species. These volunteers had varying histories of BCG vaccination and exposure to MTB, allowing us to determine the specificity of their response to TB exposure. Our results show that 1·0 μg of the purified MTB rESAT6 antigen elicited a positive skin response in both animals and humans exposed to MTB, as well as in animals exposed to M. bovis and M. marinum, all species of Mycobacteria that contain the gene for early secreted antigen target 6 (ESAT6). ESAT6 appears to be more specific to MTB infection than PPD, as demonstrated by the fact that we saw no skin responses in the BCG-vaccinated volunteers, nor in the guinea pigs sensitized with BCG vaccine, or with Mycobacteria that do not contain the gene encoding ESAT6. We believe that this is the first report of the use of a rESAT6 protein in a skin test in human volunteers, and that these data support its use in the specific detection of MTB infection.
Mannan-binding lectinMBL2gene polymorphism in chronic hepatitis C: association with the severity of liver fibrosis and response to interferon therapy
Authors: Alves Pedroso M L , Boldt A B W , Pereira-Ferrari L , Steffensen R , Strauss E , Jensenius J C , Ioshii S O , Messias-Reason I
Published: July 2010

Hepatitis C virus (HCV) is a major cause of hepatic disease and of liver transplantation worldwide. Mannan-binding lectin (MBL), encoded by the MBL2 gene, can have an important role as an opsonin and complement activating molecule in HCV persistence and liver injury. We assessed the MBL2 polymorphism in 102 Euro–Brazilian patients with moderate and severe chronic hepatitis C, paired for gender and age with 102 HCV seronegative healthy individuals. Six common single nucleotide polymorphisms in the MBL2 gene, three in the promoter (H/L, X/Y and P/Q) and three in exon 1 (A, the wild-type, and B, C or D also known as O) were evaluated using real-time polymerase chain reaction with fluorescent hybridization probes. The concentration of MBL in plasma was measured by enzyme-linked immunosorbent assay. The frequency of the YA/YO genotype was significantly higher in the HCV patients compared with the controls (P = 0·022). On the other hand, the genotypes associated with low levels of MBL (XA/XA, XA/YO and YO/YO) were decreased significantly in the patients with severe fibrosis (stage F4), when compared with the patients with moderate fibrosis (stage F2) (P = 0·04) and to the control group (P = 0·011). Furthermore, MBL2 genotypes containing X or O mutations were found to be associated with non-responsiveness to pginterferon and ribavirin treatment (P = 0·023). MBL2 polymorphisms may therefore be associated not only with the development of chronic hepatitis C, but also with its clinical evolution and response to treatment.
Secretory immunoglobulin A (IgA) responses in IgA nephropathy patients after mucosal immunization, as part of a polymeric IgA response
Authors: Eijgenraam J W , Oortwijn B D , Kamerling S W A , De Fijter J W , Van Den Wall Bake A W L , Daha M R , Van Kooten C
Published: July 2010

Secretory immunoglobulin A (SIgA), although generated at mucosal surfaces, is also found in low concentrations in the circulation. Recently, SIgA was demonstrated in mesangial deposits of patients with immunoglobulin A nephropathy (IgAN), suggesting a role in the pathogenesis. This finding is in line with the belief that high molecular weight (HMW) immunoglobulin A (IgA) is deposited in the kidney. However, there is little information on the size distribution of antigen-specific IgA in circulation upon mucosal challenge. In this study we measured antigen-specific IgA, including SIgA, in serum following challenge of IgAN patients and controls via intranasal vaccination with a neoantigen, cholera toxin subunit B (CTB). We size-fractionated serum and nasal washes to study the size distribution of total IgA, SIgA and CTB-specific IgA. Finally, we compared the size distribution of antigen-specific IgA after mucosal immunization with the distribution upon systemic immunization. A significant induction of antigen-specific SIgA was detectable in serum of both patients with IgAN and controls after mucosal immunization with CTB. Independent of the route of immunization, in both groups the antigen-specific IgA response was predominantly in the polymeric IgA fractions. This is in contrast to total IgA levels in serum that are predominantly monomeric. We conclude that mucosal challenge results in antigen-specific SIgA in the circulation, and that the antigen-specific IgA response in both IgAN patients and in controls is of predominantly HMW in nature. No differences between IgAN patients and controls were detected, suggesting that the size distribution of antigen-specific IgA in the circulation is not disturbed specifically in IgAN patients.
Serum levels of interleukin 6 in recently hospitalized tick-borne encephalitis patients correlate with age, but not with disease outcome
Authors: Toporkova M G , Aleshin S E , Ozherelkov S V , Nadezhdina M V , Stephenson J R , Timofeev A V
Published: July 2010

Infection with many encephalitic viruses is associated with the induction of the proinflammatory cytokine interleukin (IL)-6. In some situations, induction of high levels of this cytokine is associated with a protective response, but in others it can be linked to tissue damage and disease. In the studies reported here, levels of serum IL-6 and virus-specific antibodies were measured on admission to hospital and correlated with clinical outcomes. Only some patients demonstrated raised levels of serum IL-6, and there was no correlation between high levels of this cytokine and either gender or the severity of clinical disease. A statistically significant association between raised IL-6 and age was observed, with all individuals below the age of 26 showing normal levels of serum IL-6, regardless of clinical presentation. Furthermore, not all patients had detectable levels of virus-specific serum immunoglobulin G (IgG) antibodies, but an inverse and statistically significant correlation between raised IL-6 levels and IgG titre was observed. Consequently, serum levels of IL-6 cannot be used as a reliable indicator of disease outcome.
Monitoring non-immediate allergic reactions to iodine contrast media
Authors: Torres M J , Mayorga C , Cornejo-Garcia J A , Lopez S , Chaves P , Rondon C , Fernandez T , Blanca M
Published: July 2010

Non-immediate reactions to iodine contrast media (ICM) affect 2–5% of patients receiving these agents. We studied the immunological mechanisms involved in patients with a confirmed non-immediate reaction, maculopapular exanthema, after administration of ICM. The diagnosis was carried out by skin testing or drug provocation test. The immunological study was performed in sequential peripheral blood mononuclear cells taken from the onset of the reaction by flow cytometry and in skin biopsy by immunohistochemistry, with specific recognition by the lymphocyte transformation test (LTT) with different ICM. Flow cytometry showed an increase in the different activation markers [CD69, CD25 and human leucocyte antigen D-related (HLA-DR)] and the skin homing receptor [cutaneous lymphocyte-associated antigen (CLA)] in CD4 lymphocytes, whereas perforin was higher in the CD8 lymphocytes. The skin biopsy showed a perivascular mononuclear infiltrate composed of CD4 lymphocytes, expressing CD25, HLA-DR and CLA, with eosinophils. Intradermal skin tests and the LTT were positive to several ICM, including the culprit agent in four and three patients, respectively, with negative results in all 10 tolerant controls. We showed that a specific immunological mechanism was implicated in patients with non-immediate reactions to ICM. Moreover, the positive results in skin tests and lymphocyte proliferation tests indicated that an important cross-reactivity exists.
Lidocaine down-regulates nuclear factor-κB signalling and inhibits cytokine production and T cell proliferation
Authors: Lahat A , Horin S B , Lang A , Fudim E , Picard O , Chowers Y
Published: July 2010

Lidocaine is a commonly used local anaesthetic agent which has also been found to possess anti-inflammatory activity in several disorders. However, the mechanism of this effect has been little explored. The aim of this study was to investigate the effect of lidocaine on stimulated human T cells. The effect of lidocaine on Jurkat T cells was examined by enzyme-linked immunosorbent assay (ELISA) to determine secretion of interleukin (IL)-2, and by the [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] viability assay. Tumour necrosis factor (TNF)-α and IL-2 mRNA expression was determined by reverse transcription–polymerase chain reaction. In addition, the effect of lidocaine on the proliferation of freshly isolated peripheral blood (PB) CD3+ T cells was examined by carboxyfluorescein succinimidyl ester dilution. Apoptosis induction and cytokine production and secretion were determined by annexin V/PI assay, intracellular immunostaining and ELISA respectively. The results showed that lidocaine exerts a dose-dependent inhibition of IL-2 and TNF-α secretion by Jurkat T cells at the protein and mRNA levels. Moreover, lidocaine reduced nuclear factor-κB (NF-κB) signalling in clinically relevant concentrations. Similarly, proliferation of anti-CD3 stimulated PB T cells was abrogated significantly by lidocaine, and the percentage of interferon-γ- and TNF-α-producing T cells was diminished after culture with this agent. In both experimental systems, lidocaine's effect was not mediated by cytotoxic mechanism, as no significant apoptosis or necrosis was demonstrated following co-culture of T cells with this drug. In conclusion, lidocaine's anti-inflammatory effect may be mediated by a drug-induced abrogation of T cell proliferation and cytokine secretion independent of cell death. These effects are mediated at least partly by inhibition of NF-κB signalling.
T helper 1 (Th1)/Th2 cytokine expression shift of peripheral blood CD4+ and CD8+ T cells in patients at the post-acute phase of stroke
Authors: Theodorou G L , Marousi S , Ellul J , Mougiou A , Theodori E , Mouzaki A , Karakantza M
Published: July 2010

Local humoral and cellular immune responses modulate the inflammatory processes involved in the development of atherosclerotic lesions, as well as in the evolution of brain infarcts in stroke patients. The role of systemic adaptive immunity on the progression of such disease manifestations is less clear. In the current study, we evaluated the percentages of T helper 1 (Th1) [interleukin (IL)-2, interferon (IFN)-γ] and Th2 (IL-4, IL-10) cytokine-producing peripheral blood CD4+ and CD8+ T cells in 23 patients with a history of ischaemic stroke (IS) at the chronic stable phase of the disease (median post-stroke time 34·5 months). Seven stroke-free individuals matched for age and vascular risk factors (matched controls, MC) were collected for comparison. To measure cytokine values at baseline and after stimulation, we used a flow cytometry method of intracellular cytokine staining. Intrinsic Th1 and Th2 cytokine production in unstimulated T cells was negligible in all study participants. Following mitogenic stimulation with phorbol 12-myristate13-acetate/ionomycin, both the IS and the MC groups exhibited a similarly strong Th1 response; IL-2 production predominated in the CD4+ T cells and IFN-γ in the CD8+ T cells. However, when measuring the Th2 cytokine-production capacity post-stimulation, a significant increase in the percentage of IL-4-producing T cells was observed in the IS groups, compared with the MC group, resulting in a significantly lower ratio of IFN-γ-/IL-4-producing T cells. No such Th2 enhancement could be confirmed for the case of IL-10. We propose that in IS patients there is a systemic shift of the immune system towards Th2 responses at the late post-acute phase of stroke.