Potential involvement of the bone marrow in experimental Graves' disease and thyroid eye disease

Introduction

Graves' disease is an autoimmune disorder caused by auto-antibodies against the thyroid stimulating hormone receptor (TSHR). Overstimulation of the TSHR induces hyperthyroidism and thyroid eye disease (TED) as the most common extra thyroidal manifestation of Graves' disease. In TED, the TSHR cross talks with the insulin-like growth factor 1 receptor (IGF-1R) in orbital fibroblasts leading to inflammation, deposition of hyaluronan and adipogenesis. The bone marrow may play an important role in autoimmune diseases, but its role in Graves' disease and TED is unknown. Here, we investigated whether induction of experimental Graves' disease and accompanying TED involves bone marrow activation and whether interference with IGF-1R signaling prevents this activation.

Results

Immunization of mice with TSHR resulted in an increase the numbers of CD4-positive T-lymphocytes (p ≤0.0001), which was normalized by linsitinib (p = 0.0029), an increase of CD19-positive B-lymphocytes (p= 0.0018), which was unaffected by linsitinib and a decrease of GR1-positive cells (p= 0.0038), which was prevented by linsitinib (p= 0.0027). In addition, we observed an increase of Sca-1 positive hematopietic stem cells (p= 0.0007) and of stromal cell-derived factor 1 (SDF-1) (p ≤0.0001) after immunization with TSHR which was prevented by linsitinib (Sca-1: p= 0.0008, SDF-1: p ≤0.0001). TSHR-immunization also resulted in upregulation of CCL-5, IL-6 and osteopontin (all p ≤0.0001) and a concomitant decrease of the immune-inhibitory cytokines IL-10 (p= 0.0064) and PGE2 (p ≤0.0001) in the bone marrow (all p≤ 0.0001). Treatment with the IGF-1R antagonist linsitinib blocked these events (all p ≤0.0001). We further demonstrate a down-regulation of arginase-1 expression (p= 0.0005) in the bone marrow in TSHR immunized mice, with a concomitant increase of local arginine (p ≤0.0001). Linsitinib induces an upregulation of arginase-1 resulting in low arginase levels in the bone marrow. Reconstitution of arginine in bone marrow cells in vitro prevented immune-inhibition by linsitinib.

Conclusion

Collectively, these data indicate that the bone marrow is activated in experimental Graves' disease and TED, which is prevented by linsitinib. Linsitinib-mediated immune-inhibition is mediated, at least in part, by arginase-1 up-regulation, consumption of arginine and thereby immune inhibition.

Linsitinib, an IGF-1R inhibitor, attenuates disease development and progression in a model of thyroid eye disease

Introduction

Graves' disease (GD) is an autoimmune disorder caused by autoantibodies against the thyroid stimulating hormone receptor (TSHR) leading to overstimulation of the thyroid gland. Thyroid eye disease (TED) is the most common extra thyroidal manifestation of GD. Therapeutic options to treat TED are very limited and novel treatments need to be developed. In the present study we investigated the effect of linsitinib, a dual small-molecule kinase inhibitor of the insulin-like growth factor 1 receptor (IGF-1R) and the Insulin receptor (IR) on the disease outcome of GD and TED.

Methods

Linsitinib was administered orally for four weeks with therapy initiating in either the early ("active") or the late ("chronic") phases of the disease. In the thyroid and the orbit, autoimmune hyperthyroidism and orbitopathy were analyzed serologically (total anti-TSHR binding antibodies, stimulating anti TSHR antibodies, total T4 levels), immunohistochemically (H&E-, CD3-, TNFa- and Sirius red staining) and with immunofluorescence (F4/80 staining). An MRI was performed to quantify in vivo tissue remodeling inside the orbit.

Results

Linsitinib prevented autoimmune hyperthyroidism in the early state of the disease, by reducing morphological changes indicative for hyperthyroidism and blocking T-cell infiltration, visualized by CD3 staining. In the late state of the disease linsitinib had its main effect in the orbit. Linsitinib reduced immune infiltration of T-cells (CD3 staining) and macrophages (F4/80 and TNFa staining) in the orbita in experimental GD suggesting an additional, direct effect of linsitinib on the autoimmune response. In addition, treatment with linsitinib normalized the amount of brown adipose tissue in both the early and late group. An in vivo MRI of the late group was performed and revealed a marked decrease of inflammation, visualized by ¹⁹F MR imaging, significant reduction of existing muscle edema and formation of brown adipose tissue.

Conclusion

Here, we demonstrate that linsitinib effectively prevents development and progression of thyroid eye disease in an experimental murine model for Graves' disease. Linsitinib improved the total disease outcome, indicating the clinical significance of the findings and providing a path to therapeutic intervention of Graves' Disease. Our data support the use of linsitinib as a novel treatment for thyroid eye disease.

Item analysis of G8 screening in uro-oncologic geriatric patients

INTRODUCTION/BACKGROUND

The G8 score is a widespread screening tool for geriatric frailty in oncology. The aim of this study was to evaluate the scores and relevance of G8 items in a standard screening of geriatric patients with uro-oncologic diseases to better understand the results of the assessment.

METHODS

Eighty-two consecutive uro-oncologic geriatric patients aged 75 years and older were evaluated. All patients underwent a G8 screening that consisted of 8 items. Patients with a G8 score above 14 were considered geriatric "fit", while others were considered to be "frail". Overall results and single item scores were evaluated. Clinical data were gathered from patients' charts.

RESULTS

The mean age of the patients was 82 years (min. 75-max. 102). In 36 of the patients, the G8 score indicated "no-frailty", and in 46 patients, the G8 score indicated "frailty". The mean G8 score was 12.9 (min 4-max 17 pts). Item analysis revealed that points were most often lost in items H (polypharmacy), P (comparison of health status to peers) and Age. Fifty-nine, 56 and 52 patients lost points on item Age, item H and item P, respectively. In contrast, the majority of patients reached the maximum score for nutritional items [i.e., items A (food intake), B (weight loss) and F (body mass index (BMI))]. For item A, 73 patients reached the maximum score; for item B, 62 patients reached the maximum score; and for item F, 72 patients reached the maximum score. There were no differences in this distribution pattern when comparing tumour entities, sex, and patients with local vs. metastatic disease.

CONCLUSION

The present study revealed a high percentage of suspicious test results. Potential reasons for these findings include the low threshold of the G8 overall score and the fact that in some items, points were easily lost. Modifications of the test should be considered.

Macrophage-Orbital Fibroblast Interaction and Hypoxia Promote Inflammation and Adipogenesis in Graves' Orbitopathy

The inflammatory eye disease Graves' orbitopathy (GO) is the main complication of autoimmune Graves' disease. In previous studies we have shown that hypoxia plays an important role for progression of GO. Hypoxia can maintain inflammation by attracting inflammatory cells such as macrophages (MQ). Herein, we investigated the interaction of MQ and orbital fibroblasts (OF) in context of inflammation and hypoxia. We detected elevated levels of the hypoxia marker HIF-1α, the MQ marker CD68, and inflammatory cytokines TNFα, CCL2, CCL5, and CCL20 in GO biopsies. Hypoxia stimulated GO tissues to release TNFα, CCL2, and CCL20 as measured by multiplex enzyme-linked immunosorbent assay (ELISA). Further, TNFα and hypoxia stimulated the expression of HIF-1α, CCL2, CCL5, and CCL20 in OF derived from GO tissues. Immunofluorescence confirmed that TNFα-positive MQ were present in the GO tissues. Thus, interaction of M1-MQ with OF under hypoxia also induced HIF-1α, CCL2, and CCL20 in OF. Inflammatory inhibitors etanercept or dexamethasone prevented the induction of HIF-1α and release of CCL2 and CCL20. Moreover, co-culture of M1-MQ/OF under hypoxia enhanced adipogenic differentiation and adiponectin secretion. Dexamethasone and HIF-1α inhibitor PX-478 reduced this effect. Our findings indicate that GO fat tissues are characterized by an inflammatory and hypoxic milieu where TNFα-positive MQ are present. Hypoxia and interaction of M1-MQ with OF led to enhanced secretion of chemokines, elevated hypoxic signaling, and adipogenesis. In consequence, M1-MQ/OF interaction results in constant inflammation and tissue remodeling. A combination of anti-inflammatory treatment and HIF-1α reduction could be an effective treatment option.

An Early Wave of Macrophage Infiltration Intertwined with Antigen-Specific Proinflammatory T Cells and Browning of Adipose Tissue Characterizes the Onset of Orbital Inflammation in a Mouse Model of Graves' Orbitopathy

Background: Graves' orbitopathy (GO) is an autoimmune-driven manifestation of Graves' disease (GD) where pathogenic autoantibodies to the thyrotropin receptor (TSHR) activate orbital fibroblasts/preadipocytes in the orbital tissue to induce inflammation and extracellular matrix deposition. Since there are significant limitations to study immunological and proinflammatory mediator expression in early and during disease progression in GO patients, we used our experimental mouse model to elucidate early pathogenic processes. Methods: We have developed a robust mouse model of GD/GO induced by electroporation immunization of plasmid encoding human TSHR A-subunit, comprising multiple injections over a course of 15 weeks to fully recapitulate the orbital pathology. In this study, we investigated kinetics of GO development in the model by serial analyses of immunological and cellular parameters during course of orbital inflammation. Results: Pathogenic anti-TSHR antibodies with thyroid-stimulating properties developed early after the second immunization step with concomitant induction of hyperthyroidism. Examination of orbital tissue showed an early wave of macrophage infiltration followed subsequently by CD3⁺ T cells into the orbital tissue. Examination of antigen-specific T cell activity using recombinant human A-subunit protein showed high CD8⁺ T cell proliferation during this early phase of disease onset, whereas effector CD4⁺ T cells and CD25⁺FOXP3⁺ regulatory T cells (Tregs) were downregulated. The early phase of disease was also characterized by abundant presence of proinflammatory cytokines interferon-γ (IFN-γ) and tumor necrosis factor-α (TNF-α). Moreover, as the disease progressed, there was significant increase in browning of orbital fat tissue, which may be dependent on the proinflammatory milieu and/or the increased thyroid hormone levels during the established hyperthyroid status. Conclusions: This work revealed early infiltration of macrophages in the orbital region and induction of pathogenic anti-TSHR antibodies during disease onset in the model. This was followed subsequently by influx of CD8⁺ T cells specific for TSHR coupled with reduction in Tregs and substantial increase in brown adipose tissue. These new insights into the development of orbital inflammation in the model have implications for testing new therapeutic regimens by targeting macrophage function during early phases of orbital inflammation in the model.

Predicting the Course of Graves' Orbitopathy Using Serially Measured TSH-Receptor Autoantibodies by Automated Binding Immunoassays and the Functional Bioassay

The aim of the study was to investigate the use of serial measurements of TSH-receptor autoantibodies (TRAb) with the newest available assay technology to predict the course of Graves' Orbitopathy (GO) during the first 24 months from disease onset. Serial serum samples from patients with GO (103 mild/135 severe) were collected between 2007 and 2017 and retrospectively analyzed. The course of GO were classified into mild/severe 12 months after manifestation (severe: NOSPECS≥5; mild<5). TRAb were measured with automated binding immunoassays (IU/l): TRAb Elecsys (Cobas, Roche), TRAb bridge assay (IMMULITE, Siemens), and a cell-based bioassay (percent of specimen to reference ratio - SRR%) (Thyretain, Quidel). Variable cut off levels of measured TRAb were calculated at specificity of 90% from receiver operator curve (ROC) analysis for several timepoints during the course of GO. To select one: 5-8 months after first GO symptoms, which is the timepoint for usual referals for treatment mild course could be predicted at cut offs of 1.5 IU/l (Elecsys), 0.8 IU/l (Immulite) and 402% SRR (Thyretain) and the risc of severe course has to be anticipated if TRAb are above 11.6 IU/l (Elecsys), 6.5 IU/l (Thyretain), and 714% SRR (Thyretain). The Thyretain bioassay showed the highest diagnostic sensitivity (using the commercial cut off's) over the entire follow up period. TRAb measurements during the 24-month follow up of GO provide added value to the GO clinical activity and severity scores and should be used especially in the event of an unclear decision-taking situation with regard to therapy.

Predicting the Relapse of Hyperthyroidism in Treated Graves' Disease with Orbitopathy by Serial Measurements of TSH-Receptor Autoantibodies

The aim of this study was to investigate the potential of the new TSH-receptor antibody (TRAb) assays to predict remission or relapse of hyperthyroidism in patients with Graves' disease (GD) and Graves' orbitopathy (GO). TRAbs were measured retrospectively in sera from a cohort of GD patients with GO (n=117; remission n=38 and relapse n=79-Essen GO biobank) with automated binding immunoassays: TRAb Elecsys (Cobas Roche) and TRAb bridge assay (IMMULITE, Siemens), and the TSAb (thyroid stimulating Ab) cell-based bioassay (Thyretain, Quidel Corp.). To identify relapse risk/remission of hyperthyroidism patients were followed up at least 10 months after the end of antithyroid drug therapy (ATD) therapy. ROC plot analysis was performed to calculate cut-off levels of TRAb and TSAb for prediction of relapse and remission of hyperthyroidism. Cut-off serum levels are provided for timepoints around 3, 6, 10, and 15 months after the beginning of ATD. Repeated measurements of TRAb increase the rate of relapses predictions to 60% (Elecsys), 70% (IMMULITE), and 55% (Thyretain). Patients with remission have consistently TRAb levels below the cut off for relapse in repeated measurements. The cell-based bioassay was the most sensitive - and continued to be positive during follow up [at 15 months: 90% vs. 70% (IMMULITE) and 65% (Elecsys)]. Identification of relapsing hyperthyroidism is possible with automated immunoassays and cell-based bioassay especially with serial TRAb measurements during the course of ATD therapy. Patient who need eye surgery may profit from an early decision towards definitive treatment.

Modulating gut microbiota in a mouse model of Graves' orbitopathy and its impact on induced disease

BACKGROUND

Graves' disease (GD) is an autoimmune condition in which autoantibodies to the thyrotropin receptor (TSHR) cause hyperthyroidism. About 50% of GD patients also have Graves' orbitopathy (GO), an intractable disease in which expansion of the orbital contents causes diplopia, proptosis and even blindness. Murine models of GD/GO, developed in different centres, demonstrated significant variation in gut microbiota composition which correlated with TSHR-induced disease heterogeneity. To investigate whether correlation indicates causation, we modified the gut microbiota to determine whether it has a role in thyroid autoimmunity. Female BALB/c mice were treated with either vancomycin, probiotic bacteria, human fecal material transfer (hFMT) from patients with severe GO or ddH2O from birth to immunization with TSHR-A subunit or beta-galactosidase (βgal; age ~ 6 weeks). Incidence and severity of GD (TSHR autoantibodies, thyroid histology, thyroxine level) and GO (orbital fat and muscle histology), lymphocyte phenotype, cytokine profile and gut microbiota were analysed at sacrifice (~ 22 weeks).

RESULTS

In ddH2O-TSHR mice, 84% had pathological autoantibodies, 67% elevated thyroxine, 77% hyperplastic thyroids and 70% orbital pathology. Firmicutes were increased, and Bacteroidetes reduced relative to ddH2O-βgal; CCL5 was increased. The random forest algorithm at the genus level predicted vancomycin treatment with 100% accuracy but 74% and 70% for hFMT and probiotic, respectively. Vancomycin significantly reduced gut microbiota richness and diversity compared with all other groups; the incidence and severity of both GD and GO also decreased; reduced orbital pathology correlated positively with Akkermansia spp. whilst IL-4 levels increased. Mice receiving hFMT initially inherited their GO donors' microbiota, and the severity of induced GD increased, as did the orbital brown adipose tissue volume in TSHR mice. Furthermore, genus Bacteroides, which is reduced in GD patients, was significantly increased by vancomycin but reduced in hFMT-treated mice. Probiotic treatment significantly increased CD25+ Treg cells in orbital draining lymph nodes but exacerbated induced autoimmune hyperthyroidism and GO.

CONCLUSIONS

These results strongly support a role for the gut microbiota in TSHR-induced disease. Whilst changes to the gut microbiota have a profound effect on quantifiable GD endocrine and immune factors, the impact on GO cellular changes is more nuanced. The findings have translational potential for novel, improved treatments. Video abstract.

Comparative Prey Spectra Analyses on the Endangered Aquatic Carnivorous Waterwheel Plant (Aldrovanda vesiculosa, Droseraceae) at Several Naturalized Microsites in the Czech Republic and Germany

The critically endangered carnivorous waterwheel plant (Aldrovanda vesiculosa, Droseraceae) possesses underwater snap traps for capturing small aquatic animals, but knowledge on the exact prey species is limited. Such information would be essential for continuing ecological research, drawing conclusions regarding trapping efficiency and trap evolution, and eventually, for conservation. Therefore, we performed comparative trap size measurements and snapshot prey analyses at seven Czech and one German naturalized microsites on plants originating from at least two different populations. One Czech site was sampled twice during 2017. We recorded seven main prey taxonomic groups, that is, Cladocera, Copepoda, Ostracoda, Ephemeroptera, Nematocera, Hydrachnidia, and Pulmonata. In total, we recorded 43 different prey taxa in 445 prey-filled traps, containing in sum 461 prey items. With one exception, prey spectra did not correlate with site conditions (e.g. water depth) or trap size. Our data indicate that A. vesiculosa shows no prey specificity but catches opportunistically, independent of prey species, prey mobility mode (swimming or substrate-bound), and speed of movement. Even in cases where the prey size exceeded trap size, successful capture was accomplished by clamping the animal between the traps' lobes. As we found a wide prey range that was attracted, it appears unlikely that the capture is enhanced by specialized chemical- or mimicry-based attraction mechanisms. However, for animals seeking shelter, a place to rest, or a substrate to graze on, A. vesiculosa may indirectly attract prey organisms in the vicinity, whereas other prey capture events (like that of comparably large notonectids) may also be purely coincidental.

Gut Microbiome in BALB/c and C57BL/6J Mice Undergoing Experimental Thyroid Autoimmunity Associate with Differences in Immunological Responses and Thyroid Function

Experimental models of hyperthyroid Graves' disease (GD) and Graves' orbitopathy (GO) are efficiently developed by genetic immunisation by electroporation with human thyrotropin hormone receptor (hTSHR) A-subunit plasmid in female BALB/c (H-2d) mice. We investigated susceptibility in C57BL/6 J (H-2b) animals to allow studies on disease mechanisms in transgenic and immune response gene knock-out mice. Higher numbers of female C57BL/6 J were positive for pathogenic thyroid stimulating antibodies, but induced hyperthyroidism remained at a low frequency compared to BALB/c animals. Assessment of hTSHR specific T cells showed reduced proliferation in C57BL/6 J animals accompanied with anti-inflammatory IL-10, with less pro-inflammatory IFN-γ compared to BALB/c. Whilst the orbital tissue from immune BALB/c mice showed inflammation and adipogenesis, in contrast C57BL/6 J animals showed normal pathology. We characterised the gut microbiota using 16 S ribosomal RNA gene sequencing to explore its possible pathogenic role in the model. Despite being housed under identical conditions, we observed significantly different organisation of the microbiota (beta-diversity) in the two strains. Taxonomic differences were also noted, with C57BL/6 J showing an enrichment of Operational Taxonomic Units (OTUs) belonging to the Paludibacter and Allobaculum, followed by Limibacter, Anaerophaga and Ureaplasma genera. A higher number of genera significantly correlating with clinical features was observed in C57BL/6 J compared to BALB/c; for example, Limibacter OTUs correlated negatively with thyroid-stimulating antibodies in C57BL/6 J mice. Thus, our data suggest gut microbiota may play a pivotal immunomodulatory role that differentiates the thyroid function and orbital pathology outcome in these two inbred strains undergoing experimental GO.

Noninflammatory Diffuse Follicular Hypertrophy/Hyperplasia of Graves Disease: Morphometric Evaluation in an Experimental Mouse Model

OBJECTIVES

Experimental models of Graves hyperthyroid disease accompanied by Graves orbitopathy (GO) can be efficiently induced in susceptible inbred strains of mice by immunization by electroporation of heterologous human TSH receptor (TSHR) A-subunit plasmid. The interrelated pathological findings in the thyroid glands of Graves disease (GD) that explain the core changes classically include diffuse follicular hyperplasia and multifocal mild lymphocytic infiltrate. However, the relative contributions of different thyroid tissue components (colloid, follicular cells, and stroma) have not been previously evaluated. In this study, we characterize the thyroid gland of an experimental mouse model of autoimmune GD. Our objective was to define the relative contribution of the different thyroid tissue components to the pathology of glands in the experimental model.

METHODS

Mice were immunized with human TSHR A-subunit plasmid. Antibodies induced to human TSHR were pathogenic in vivo due to their cross-reactivity to mouse TSHR.

RESULTS

Autoimmune thyroid disease in the model was characterized by histopathology of hyperplastic glands with large follicular cells. Further examination of thyroid glands of immunized animals revealed a significantly increased follicular area and follicle/stroma ratio, morphometrically correlated with a noninflammatory follicular hyperplasia/hypertrophy. The increased follicle/stroma ratio was the most relevant morphometrically variable summarizing the pathological changes for screening purposes.

CONCLUSION

GD thyroid glands are enlarged and characterized by a noninflammatory diffuse follicular cell hyperplasia/hypertrophy and a significant increase in the follicles with an increased follicle/stroma ratio. Overall, this mouse model is a faithful model of an early hyperthyroid status of GD (diffuse glandular involvement and follicular expansion).

Gut microbiota in experimental murine model of Graves' orbitopathy established in different environments may modulate clinical presentation of disease

BACKGROUND

Variation in induced models of autoimmunity has been attributed to the housing environment and its effect on the gut microbiota. In Graves' disease (GD), autoantibodies to the thyrotropin receptor (TSHR) cause autoimmune hyperthyroidism. Many GD patients develop Graves' orbitopathy or ophthalmopathy (GO) characterized by orbital tissue remodeling including adipogenesis. Murine models of GD/GO would help delineate pathogenetic mechanisms, and although several have been reported, most lack reproducibility. A model comprising immunization of female BALBc mice with a TSHR expression plasmid using in vivo electroporation was reproduced in two independent laboratories. Similar orbital disease was induced in both centers, but differences were apparent (e.g., hyperthyroidism in Center 1 but not Center 2). We hypothesized a role for the gut microbiota influencing the outcome and reproducibility of induced GO.

RESULTS

We combined metataxonomics (16S rRNA gene sequencing) and traditional microbial culture of the intestinal contents from the GO murine model, to analyze the gut microbiota in the two centers. We observed significant differences in alpha and beta diversity and in the taxonomic profiles, e.g., operational taxonomic units (OTUs) from the genus Lactobacillus were more abundant in Center 2, and Bacteroides and Bifidobacterium counts were more abundant in Center 1 where we also observed a negative correlation between the OTUs of the genus Intestinimonas and TSHR autoantibodies. Traditional microbiology largely confirmed the metataxonomics data and indicated significantly higher yeast counts in Center 1 TSHR-immunized mice. We also compared the gut microbiota between immunization groups within Center 2, comprising the TSHR- or βgal control-immunized mice and naïve untreated mice. We observed a shift of the TSHR-immunized mice bacterial communities described by the beta diversity weighted Unifrac. Furthermore, we observed a significant positive correlation between the presence of Firmicutes and orbital-adipogenesis specifically in TSHR-immunized mice.

CONCLUSIONS

The significant differences observed in microbiota composition from BALBc mice undergoing the same immunization protocol in comparable specific-pathogen-free (SPF) units in different centers support a role for the gut microbiota in modulating the induced response. The gut microbiota might also contribute to the heterogeneity of induced response since we report potential disease-associated microbial taxonomies and correlation with ocular disease.

Genetic immunization with mouse thyrotrophin hormone receptor plasmid breaks self-tolerance for a murine model of autoimmune thyroid disease and Graves' orbitopathy

Experimental models of Graves' hyperthyroid disease accompanied by Graves' orbitopathy (GO) can be induced efficiently in susceptible inbred strains of mice by immunization by electroporation of heterologous human TSH receptor (TSHR) A-subunit plasmid. In this study, we report on the development of a bona fide murine model of autoimmune Graves' disease induced with homologous mouse TSHR A-subunit plasmid. Autoimmune thyroid disease in the self-antigen model was accompanied by GO and characterized by histopathology of hyperplastic glands with large thyroid follicular cells. Examination of orbital tissues showed significant inflammation in extra-ocular muscle with accumulation of T cells and macrophages together with substantial deposition of adipose tissue. Notably, increased levels of brown adipose tissue were present in the orbital tissue of animals undergoing experimental GO. Further analysis of inflammatory loci by ¹⁹ F-magnetic resonance imaging showed inflammation to be confined to orbital muscle and optic nerve, but orbital fat showed no difference in inflammatory signs in comparison to control β-Gal-immunized animals. Pathogenic antibodies induced to mouse TSHR were specific for the self-antigen, with minimal cross-reactivity to human TSHR. Moreover, compared to other self-antigen models of murine Graves' disease induced in TSHR knock-out mice, the repertoire of autoantibodies to mouse TSHR generated following the breakdown of thymic self-tolerance is different to those that arise when tolerance is not breached immunologically, as in the knock-out models. Overall, we show that mouse TSHR A-subunit plasmid immunization by electroporation overcomes tolerance to self-antigen to provide a faithful model of Graves' disease and GO.

Hypoxia-Dependent HIF-1 Activation Impacts on Tissue Remodeling in Graves' Ophthalmopathy-Implications for Smoking

CONTEXT

In Graves' ophthalmopathy (GO), inflammation with tissue expansion in a closed compartment like the bony orbit and smoking may cause tissue hypoxia.

OBJECTIVES

In this study, we investigated whether hypoxia-inducible factor-1 (HIF-1) action impacts on tissue remodeling in GO with the aim to identify possible new therapeutic targets.

DESIGN/SETTING/PARTICIPANTS

Orbital fibroblasts (OFs) were derived from GO patients and control (Ctrl) persons. We analyzed HIF-1α levels in response to hypoxia and cigarette smoke extract, as well as HIF-1-dependent vascular endothelial growth factor (VEGF) release and adipogenic differentiation, by using HIF-1α small interfering RNA, or HIF-1 inhibitor BAY 87-2243.

MAIN OUTCOME MEASURES

Western blot, real-time PCR, ELISA, and immunohistochemistry were used to analyze HIF-1α, VEGF, CD31, and adiponectin. Adipogenic differentiation was measured with Nile red assay.

RESULTS

Higher HIF-1α levels in OFs were correlated with the clinical activity score of GO patients. Cigarette smoke extract elevated HIF-1α levels. HIF-1-dependent VEGF secretion was enhanced in GO-OF compared to Ctrl-OF, and as an in vivo consequence, we found a higher vessel density in GO tissue than in Ctrl tissue. Hypoxia strongly stimulated HIF-1-dependent adipogenesis and adiponectin release of GO-OF and enhanced TSH receptor-mediated adipogenesis.

CONCLUSIONS

Hypoxia impacts on tissue remodeling in GO by stimulating angiogenesis and adipogenesis through activation of HIF-1-dependent pathways in OFs. Our results offer a molecular mechanism for the detrimental influence of smoking on GO and an explanation as to why decompression can improve the outcome of patients. Drug-targeted inhibition of HIF-1/VEGF may provide a therapeutic option to control tissue expansion in GO.

Pathogenic Phenotype of Adipogenesis and Hyaluronan in Orbital Fibroblasts From Female Graves' Orbitopathy Mouse Model

A mouse model of Graves' orbitopathy (GO) induced by genetic immunization of human TSH receptor (TSHR) A-subunit encoding plasmid has recently been established. The orbital pathology was characterized by adipogenesis, myopathy and fibrosis. Human orbital fibroblasts (OFs) express TSHR and IGF-1 receptor (IGF-1R) and are considered to be pathogenic in GO. We established conditions for growing ex vivo cultures of mouse OFs (mOFs) from orbital tissue of animals undergoing GO and controls. Early passage mOFs showed characteristic fibroblast morphology and expressed mesenchymal stem cell markers including a strong expression of CD90.2 and CD40, whereas display of CD73 and all other leucocyte markers was uniformly absent. Importantly, OFs derived from GO mice expressed elevated levels of TSHR and IGF-1R and showed enhanced adipogensis compared with controls. Activation of TSHR in mOFs from GO animals with TSH, monoclonal thyroid-stimulating antibody M22, or stimulation of IGF-1R with IGF-1-induced hyaluronan secretion to significantly elevated levels compared with control animals. Hyaluronan synthase 2 was more abundant in OFs derived from GO mice. In conclusion, mOFs established from GO model recapitulate the pathogenicity of human OFs from GO patients by their increased propensity for adipogenesis and hyaluronan production leading to disease activity. To our knowledge, this is the first report to show mOFs from the preclinical GO model have pathogenic properties that will aid in understanding the molecular and genetic changes during progression to adipogenesis and hyaluronan deposition to provide new insights into GO pathogenesis.

Comparative Assessment of Female Mouse Model of Graves' Orbitopathy Under Different Environments, Accompanied by Proinflammatory Cytokine and T-Cell Responses to Thyrotropin Hormone Receptor Antigen

We recently described a preclinical model of Graves' orbitopathy (GO), induced by genetic immunization of eukaryotic expression plasmid encoding human TSH receptor (TSHR) A-subunit by muscle electroporation in female BALB/c mice. The onset of orbital pathology is characterized by muscle inflammation, adipogenesis, and fibrosis. Animal models of autoimmunity are influenced by their environmental exposures. This follow-up study was undertaken to investigate the development of experimental GO in 2 different locations, run in parallel under comparable housing conditions. Functional antibodies to TSHR were induced in TSHR A-subunit plasmid-immunized animals, and antibodies to IGF-1 receptor α-subunit were also present, whereas control animals were negative in both locations. Splenic T cells from TSHR A-subunit primed animals undergoing GO in both locations showed proliferative responses to purified TSHR antigen and secreted interferon-γ, IL-10, IL-6, and TNF-α cytokines. Histopathological evaluation showed orbital tissue damage in mice undergoing GO, manifest by adipogenesis, fibrosis, and muscle damage with classic signs of myopathy. Although no inflammatory infiltrate was observed in orbital tissue in either location, the appearances were consistent with a "hit-and-run" immune-mediated inflammatory event. A statistically significant increase of cumulative incidence of orbital pathology when compared with control animals was shown for both locations, confirming onset of orbital dysimmune myopathy. Our findings confirm expansion of the model in different environments, accompanied with increased prevalence of T cell-derived proinflammatory cytokines, with relevance for pathogenesis. Wider availability of the model makes it suitable for mechanistic studies into pathogenesis and undertaking of novel therapeutic approaches.

[Differential diagnosis of hematuria]

Hematuria is the main symptom of many urological and nephrological diseases. In the differential diagnostics a distinction is made between painful and pain-free and between macrohematuria which is visible to the naked eye and microhematuria which is not visible. The reasons for hematuria are basically renal (glomerular) and non-renal (non-glomerular) causes. In order not to overlook early symptoms of malignant and relevant benign diseases and also to avoid excessive diagnostic tests, a differentiated approach is necessary.

TRPC1 regulates fMLP-stimulated migration and chemotaxis of neutrophil granulocytes

Neutrophils form the first line of defense of the innate immune system and are rapidly recruited by chemotactic signals to sites of inflammation. Understanding the mechanisms of neutrophil chemotaxis is therefore of great interest for the potential development of new immunoregulatory therapies. It has been shown that members of the transient receptor potential (TRP) family of cation channels are involved in both cell migration and chemotaxis. In this study, we demonstrate that TRPC1 channels play an important role in fMLP mediated chemotaxis and migration of murine neutrophils. The knock-out of TRPC1 channels leads to an impaired migration, transmigration and chemotaxis of the neutrophils. In contrast, Ca²⁺ influx but not store release after activation of the TRPC1(-/-) neutrophils with fMLP is strongly enhanced. We show that the enhanced Ca²⁺ influx in the TRPC1(-/-) neutrophils is associated with a steepened front to rear gradient of the intracellular Ca²⁺ concentration with higher levels at the cell rear. Taken together, this paper highlights a distinct role of TRPC1 in neutrophil migration and chemotaxis. We propose that TRPC1 controls the activity of further Ca²⁺ influx channels and thus regulates the maintenance of intracellular Ca²⁺ gradients which are critical for cell migration. This article is part of a Special Issue entitled: 13th European Symposium on Calcium.

[Prostate cancer]

For many clinical issues regarding prostate cancer magnetic resonance imaging (MRI) is gaining increasing importance for prostate diagnostics. The high morphological resolution of T2-weighted sequences is unsurpassed compared to other imaging modalities. It enables not only the detection and localization of prostate cancer but also allows the evaluation of extracapsular extensions. Functional MRI methods, such as diffusion-weighted imaging (DWI), dynamic contrast-enhanced (DCE) MRI and proton magnetic resonance spectroscopy ((1)H-MRS) increase the specificity and to a lesser extent, the sensitivity of diagnostics. In accordance with the interdisciplinary S3 guidelines, prostate MRI is recommended for patients with at least one negative biopsy for cancer detection. According to the guidelines areas suspected of being cancerous should be selectively biopsied in addition to the systematic biopsy. The transmission of findings about the suspected tumor areas according to the structured PI-RADS classification system has proven its worth. The localization and staging of prostate carcinoma is best achieved with the help of MRI and is recommended in the S3 guidelines especially for tumors with a clinical stage cT3/4 or with a Gleason grading system score ≥8. In addition to these applications MRI is mainly used under study conditions for local recurrence or active surveillance.

Pre-prostatic tissue removed in robotic assisted lymph node dissection for prostate cancer contains lymph nodes

Objective:

The on-going discussion about extent and best template for pelvic lymph dissection (PLND) motivated us to analyse pre-prostatic tissue (PPT) for lymph nodes and metastases.

Materials and Methods:

From December 2010 to August 2011 PPT was sent for histopathological evaluation during 80 robotic assisted radical prostatectomies (RARP) and one extended staging lymph node dissection. All patients had either a limited (lPLND, n = 44) or an extended lymph node dissection (ePLND, n = 36). Clinical data were retrospectively analyzed and compared to histopathological findings.

Results:

Lymph nodes were found in PPT in 10/80 (12.5%) patients after RARP and in the one patient after staging ePLND. Mean number of lymph nodes detected in PPT of them was 1.2 (range 1-3). Clinically no differences were found between patients with or without lymph nodes in PPT. In the standard template of either ePLND or lPLND the average number of lymph nodes was 13 (range 2-56). Herein metastases were found in 10 (12.5%) patients after RARP and in the patient after staging ePLND. A metastasis in PPT was only found after staging ePLND.

Conclusions:

Pre-prostatic tissue might contain lymph nodes that potentially harbour metastases. In the intention to perform the most accurate staging this tissue should be considered for histopathological evaluation.

[Technique of the urethral anastomosis in orthotopic neo-bladder following robot-assisted radical cystectomy (RARC)]

The urethral anastomosis in extracorporeally constructed orthotopic neo-bladder following robot-assisted radical cystectomy (RARC) remains a challenge. In principle either pre-posi-tioned single sutures or robotic continuous suture techniques can be applied. In the literature the different techniques are most often not described in detail. In the present work one example for each technique is given and the advantages and disadvantages of both methods are discussed.

[The urethral anastomosis in orthotopic neobladder following robot-assisted radical cystectomy (RARC) at German-speaking centres]

INTRODUCTION

Following robot-assisted radical cystectomy (RARC) and extracorporeal reconstruction, robotic continuous suture techniques and those using open or robotically pre-positioned single sutures are used for the urethroneovesical anastomosis.

METHODS

62 German-speaking robotic centres were asked in an online questionnaire whether they carried out RARC. Following an affirmative answer further questions were put to the form of the neobladder and the technique of the urethrovesical anastomosis.

RESULTS

80% of the online questionnaires were answered. 44% (n=22) of these centres perform the RARC. According to the answers, given all of the centres but one perform an extracorporeal construction of the neobladder [Studer bladder 73% (n=16), Hautmann bladder 18% (n=4), others 9% (n=2)]. After reconstruction 36% (n=8) of the teams perform a completely open surgical anastomosis with pre-positioned sutures, 24% (n=5) close the anastomosis in a single knot technique using robotically pre-positioned sutures and 40% (n=9) use continuous sutures during the intracorporeal reconstruction or after re-docking the robot.

CONCLUSION

According to this questionnaire to German-speaking centres the most common anastomotic technique following extracorporeal reconstruction, mostly a Studer bladder, is that of the pre-positioned single knot sutures. This offers the advantage that a re-docking of the robotic cart is unnecessary. In contrast, however, to robotically performed suturing, there must be enough space in the open procedure to surgically tie-off the sutures of the anastomosis.

Establishment of a protocol for large-scale gene expression analyses of laser capture microdissected bladder tissue

PURPOSE

Lower urinary tract symptoms (LUTS) can be caused by structural and functional changes in different compartments of the bladder. To enable extensive investigations of individual regions even in small bladder biopsies, we established a combination protocol consisting of three molecular techniques: laser capture microdissection microscopy (LCM), RNA preamplification and quantitative polymerase chain reaction (qPCR).

METHODS

Urinary bladders of ten mice were resected and frozen immediately or after a delay of 15 min. Cryosections were obtained and smooth muscle was isolated using the LCM technique. Then, RNA was extracted, including protocols with and without DNase digestion as well as with and without the addition of carrier RNA. Extracted RNA was either used for reverse transcriptase (RT)-PCR plus qPCR or for a combination of RNA preamplification and qPCR.

RESULTS

Our data showed that with RNA preamplification, 10 μg cDNA can be regularly generated from 2.5 ng RNA. Depending on expression levels, this is sufficient for hundreds of pPCR reactions. The efficiency of preamplification, however, was gene-dependent. DNase digestion before preamplification lead to lower threshold cycles in qPCR. The use of partly degraded RNA for RNA preamplification did not change the results of the following qPCR.

CONCLUSIONS

RNA preamplification strongly enlarges the spectrum of genes to be analyzed in distinct bladder compartments by qPCR. It is an easy and reliable method that can be realized with standard laboratory equipment. Our protocol may lead in near future to a better understanding of the pathomechanisms in LUTS.

Identification of germline susceptibility loci in ETV6-RUNX1-rearranged childhood acute lymphoblastic leukemia

Acute lymphoblastic leukemia (ALL) is a malignant disease of the white blood cells. The etiology of ALL is believed to be multifactorial and likely to involve an interplay of environmental and genetic variables. We performed a genome-wide association study of 355 750 single-nucleotide polymorphisms (SNPs) in 474 controls and 419 childhood ALL cases characterized by a t(12;21)(p13;q22) - the most common chromosomal translocation observed in childhood ALL - which leads to an ETV6-RUNX1 gene fusion. The eight most strongly associated SNPs were followed-up in 951 ETV6-RUNX1-positive cases and 3061 controls from Germany/Austria and Italy, respectively. We identified a novel, genome-wide significant risk locus at 3q28 (TP63, rs17505102, P(CMH)=8.94 × 10(-9), OR=0.65). The separate analysis of the combined German/Austrian sample only, revealed additional genome-wide significant associations at 11q11 (OR8U8, rs1945213, P=9.14 × 10(-11), OR=0.69) and 8p21.3 (near INTS10, rs920590, P=6.12 × 10(-9), OR=1.36). These associations and another association at 11p11.2 (PTPRJ, rs3942852, P=4.95 × 10(-7), OR=0.72) remained significant in the German/Austrian replication panel after correction for multiple testing. Our findings demonstrate that germline genetic variation can specifically contribute to the risk of ETV6-RUNX1-positive childhood ALL. The identification of TP63 and PTPRJ as susceptibility genes emphasize the role of the TP53 gene family and the importance of proteins regulating cellular processes in connection with tumorigenesis.

Kidney-specific cadherin correlates with the ontogenetic origin of renal cell carcinoma subtypes: an indicator of a malignant potential?

INTRODUCTION AND OBJECTIVES

To evaluate retrospectively kidney-specific cadherin (Ksp-cad) expression in renal cell carcinoma (RCC) subtypes and oncocytoma in correlation with its ontogenetic origin of distal and proximal tubules and to correlate Ksp-cad expression with tumour characteristics.

MATERIALS AND METHODS

Membranous and cytoplasmic expression of Ksp-cad was determined in 40 clear cell (ccRCC), 25 papillary (pRCC), 19 chromophobe carcinomas (chRCC), 27 oncocytomas (oncocytomas) (n = 111) and 32 benign kidney parenchyma specimens separated in distal tubules (DT) and proximal tubules (PT) by immunohistochemistry using tissue microarray technique. Staining intensity was quantified as a score ranging from 0 to 12. Comparison of data and correlation with tumour characteristics were done by Wilcoxon/Kruskal-Wallis tests (post hoc Tukey-Kramer analysis).

RESULTS

In benign renal tissue, membranous and cytoplasmic expression of Ksp-cad in the DT was significantly higher than that in the PT (12.0 ± 0 vs. 5.2 ± 0.3 and 6.3 ± 0.5 vs. 0.0 ± 0.0, respectively; (P < 0.05)). Membranous KSP-cad expression was significantly higher in chRCC (5.2 ± 0.8) and oncocytomas (3.7 ± 0.4) than that in ccRCC (0.8 ± 0.2) and pRCC (1.4 ± 0.4; P < 0.05), while expression between oncocytomas and chRCC did not differ significantly. In RCC, Ksp-cad expression was significantly associated with higher T stage and the occurrence of synchronous metastasis (P < 0.05). Higher N stages and grading tended to correlate with a lower Ksp-cad expression.

CONCLUSIONS

In this cohort, the origin of tumour subtypes-chRCC and oncocytomas develop from DT and ccRCC and pRCC from PT cells-is mirrored by the respective Ksp-cad expression. This raises the question whether DT-derived tumours have a less malignant potential than PT-derived tumours.

Complications of a buried penis in an extremely obese patient

The buried penis syndrome in adults is a rare condition of different aetiologies. Today extreme obesity is considered as a major contributor. We present a case of a 30-year-old extremely obese patient (BMI 65 kg/m(2)) with purulent infection of the penile cavity, a phlegmon of the mons pubis and urinary retention due to a buried penis. Whereas acute complications of a buried penis in obese patients include local infection and urinary retention, chronic problems are undirected voiding, disturbed vaginal penetration and erectile dysfunction. Even though several surgical techniques are described, weight reduction should be primarily preferred.

[Robotic laparoscopic cystectomy: on the way to a standard procedure?]

INTRODUCTION

Radical cystectomy is considered the standard treatment for muscle-invasive bladder cancer. Minimally invasive techniques - especially robot-assisted techniques (RARC) - are being increasingly employed for this indication. Herein, we evaluate the current status of RARC and its acceptance in the urological community.

RESULTS

The field of RARC is steadily increasing particularly due to an extremely short learning curve for surgeons with previous experience in robot-assisted radical prostatectomy. Lymph node yield has been shown to be adequate in several independent studies, being comparable to that of the open approach. Urinary diversion is most frequently done extracorporeally while several groups have commited themselves to intracorporeal techniques and have already shown excellent results. The perioperative outcome data compare favourably to those of open cystectomy. Short-term and interim oncological data are promising while a final long-term assessment is still lacking.

CONCLUSIONS

RARC completed by appropriate urinary diversion is gaining relevance in academic institutions worldwide. The relatively wide availability of the robotic system will further add to this development. Secondary to the final assessment of its oncological efficacy RARC has the potential to become a standard treatment of muscle-invasive bladder cancer since its perioperative efficacy is excellent.

[Brucellosis as a differential diagnosis of cancer of the testes]

Brucellosis has become a rarity in industrialized countries. The manifestation as a granulomatous inflammation of the testes is described with an incidence of 5-40% in the literature and therefore is a relatively common complication of brucellosis. In cases of pain of the testes combined with B symptoms, a systemic inflammation with a local complication should also be considered besides cancer of the testes.

[Peyronie's disease-often a disabling disease for sexually active men]

Peyronie's disease is an acquired penile condition characterized by fibrous plaques between the tunica albuginea and the subtunical tissue of the corpora cavernosa. Plaques are considered responsible for the main symptoms: penile pain and deviation. Even though several risk factors and associations with other diseases are known its exact aetiology remains unclear. Most commonly discussed hypotheses are micro traumata, inflammatory and/or ischemic processes. Currently different treatment forms exist raging form systemic or local medical treatment, to physical applications and surgery. All treatment forms are symptom based and evidence based treatment remains difficult to establish. Because conservative treatment is of limited success in many patients especially with severe deviations surgery becomes necessary.

Blended E-learning in a Web-based virtual hospital: a useful tool for undergraduate education in urology

INTRODUCTION

E-learning is a teaching tool used successfully in many medical subspecialties. Experience with its use in urology, however, is scarce. We present our teaching experience with the INMEDEA simulator to teach urological care to medical students.

METHODS

The INMEDEA simulator is an interactive e-learning system built around a virtual hospital which includes a department of urology. It allows students to solve virtual patient cases online. In this study, students were asked to prepare two urological cases prior to discussion of the cases in small groups. This blended teaching approach was evaluated by students through anonymous questionnaires.

RESULTS

Of 70 4th year medical students 76% judged this teaching method as good or very good. Eighty-seven percent felt that it offered a good way to understand urological diseases better and 72% felt that learning with this method was fun. Nevertheless, 30 out of 70 free text statements revealed that further improvements of the program, including an easier and more comfortable navigation and a faster supply of information are necessary.

CONCLUSIONS

Virtual patient cases offer a practicable solution for teaching based on problem solving in urology with a high acceptance rate by students.

Economic aspects of bladder cancer: what are the benefits and costs?

OBJECTIVE

Bladder cancer (BC) has the highest lifetime treatment costs per patient of all cancers. The high recurrence rate and ongoing invasive monitoring requirement are the key contributors to the economic and human toll of this disease. The purpose of this paper was to utilize the recent literature to identify opportunities for improving the benefits and costs of BC care.

METHODS

A PubMed search was performed of recent publications concerning (BC) cost-effectiveness. We reviewed studies, reviews, opinion papers and cost-effectiveness analyses, focusing primarily on non-muscle-invasive bladder cancer (Ta/T1; NMIBC).

RESULTS

New diagnostic tools such as urine markers may assist in more cost-effectively detecting BC at an earlier stage, however, these markers cannot replace the cystoscopy, which is the current standard of care. A photodynamic diagnostic tool (PDD) using hexylaminolevulinate (Hexvix) enhances tumor visibility and improves transurethral resection of bladder cancer (TURB) results, potentially reducing recurrence rates and lowering treatment costs. While the importance of BC research has been acknowledged, research investment has been continuously reduced during the last 5 years.

CONCLUSIONS

The economic burden of BC is well-characterized in the literature. This study suggests that new technologies (i.e., urine-based tests, PDD) and therapeutic regimes (intravesical chemotherapy, adjuvant immunotherapy) have significant potential to improve the diagnosis, treatment and on-going monitoring of BC patients, with potential improvements in clinical outcomes and concurrent cost-savings. A renewed interest and investment in BC research are required to ensure future advancements.

Cooperative genetic defects in TLX3 rearranged pediatric T-ALL

T-cell acute lymphoblastic leukemia (T-ALL) is an aggressive neoplastic disorder, in which multiple genetic abnormalities cooperate in the malignant transformation of thymocytes. About 20% of pediatric T-ALL cases are characterized by TLX3 expression due to a cryptic translocation t(5;14)(q35;q32). Although a number of collaborating genetic events have been identified in TLX3 rearranged T-ALL patients (NOTCH1 mutations, p15/p16 deletions, NUP214-ABL1 amplifications), further elucidation of additional genetic lesions could provide a better understanding of the pathogenesis of this specific T-ALL subtype. In this study, we used array-CGH to screen TLX3 rearranged T-ALL patients for new chromosomal imbalances. Array-CGH analysis revealed five recurrent genomic deletions in TLX3 rearranged T-ALL, including del(1)(p36.31), del(5)(q35), del(13)(q14.3), del(16)(q22.1) and del(19)(p13.2). From these, the cryptic deletion, del(5)(q35), was exclusively identified in about 25% of TLX3 rearranged T-ALL cases. In addition, 19 other genetic lesions were detected once in TLX3 rearranged T-ALL cases, including a cryptic WT1 deletion and a deletion covering the FBXW7 gene, an U3-ubiquitin ligase that mediates the degradation of NOTCH1, MYC, JUN and CyclinE. This study provides a genome-wide overview of copy number changes in TLX3 rearranged T-ALL and offers great new challenges for the identification of new target genes that may play a role in the pathogenesis of T-ALL.