Udo Schneider

Detection of Rheumatoid Arthritis Using Non-Specific Contrast Enhanced Fluorescence Imaging

RATIONALE AND OBJECTIVES The aim of this study was to develop a new tool for the early detection of inflammatory joint diseases using fluorescence imaging in the near-infrared (NIR) spectral range following the intravenous administration of an unspecific contrast agent. MATERIALS AND METHODS A laser-supported system for fluorescence imaging of finger joints was designed and constructed. Five patients and a corresponding number of volunteers were examined using 0.1 mg/kg by weight of indocyanine green as an unspecific contrast agent. Fluorescence images were acquired continuously over a period of 15 minutes. As a control, 1 day before optical imaging, all patients and volunteers underwent contrast-enhanced magnetic resonance imaging (MRI) at 0.2 T. On the basis of MRI findings, all examined joints were divided into four groups: no change and mild, moderate, and severe synovitis. The emitted fluorescence photons were quantified in different regions of interest covering the finger joints and finger tips. The normalized fluorescence intensity of contrast agents was compared with MRI findings as a proven standard. RESULTS NIR dyes of the cyanine class are enriched in inflammatory joints and show a different kinetic behavior compared to normal joints after bolus injection. These findings demonstrate clearly the capability of contrast-enhanced fluorescence imaging to detect early changes caused by rheumatoid arthritis in finger joints. The NIR results were correlated with MRI findings (r = 0.84). CONCLUSION Contrast-enhanced fluorescence imaging provides adequate information for the evaluation of inflammatory involvement of finger joints comparable to low-field MRI.

Urinary CD4 T cells identify SLE patients with proliferative lupus nephritis and can be used to monitor treatment response

Objectives Proliferative lupus nephritis (LN) is one of the major concerns in the treatment of systemic lupus erythematosus (SLE). Here we evaluate urinary CD4 T cells as a biomarker of active LN and indicator of treatment response. Methods Urinary CD3CD4 T cells were quantified using flow cytometry in 186 urine samples from 147 patients with SLE. Fourteen patients were monitored as follow-up. Thirty-one patients with other nephropathies and 20 healthy volunteers were included as controls. Results In SLE, urinary CD4 T cell counts ≥800/100 ml were observed exclusively in patients with active LN. Receiver operator characteristic analysis documented clear separation of SLE patients with active and non-active LN (area under the curve 0.9969). All patients with up-to-date kidney biopsy results showing proliferative LN had high urinary CD4 T cell numbers. In patients monitored under therapy, normalisation of urinary CD4 T cell counts indicated lower disease activity and better renal function. In contrast, patients with persistence of, or increase in, urinary T cells displayed worse outcomes. Conclusions Urinary CD4 T cells are a highly sensitive and specific marker for detecting proliferative LN in patients with SLE. Furthermore, monitoring urinary CD4 T cells may help to identify treatment responders and treatment failure and enable patient-tailored therapy in the future.

Nuclear actin aggregation is a hallmark of anti-synthetase syndrome–induced dysimmune myopathy

Objective: To analyze antisynthetase syndrome–associated myositis by modern myopathologic methods and to define its place in the spectrum of idiopathic inflammatory myopathies (IIMs). Methods: Skeletal muscle biopsies from antisynthetase syndrome–associated myositis and other IIMs from different institutions worldwide were analyzed by histopathology, quantitative PCR, and electron microscopy. Results: Myonuclear actin filament inclusions were identified as a unique morphologic hallmark of antisynthetase syndrome–associated myositis. Nuclear actin inclusions were never found in dermatomyositis, polymyositis, sporadic inclusion body myositis, autoimmune necrotizing myopathy associated with signal recognition particle or 3-hydroxy-3-methylglutaryl-coenzyme A reductase autoantibodies, or nonspecific myositis associated with other systemic diseases, harboring myositis-associated autoantibodies, and presenting myofiber necrosis. We show that molecules involved in actin filament formation and actin shuttling mechanisms are altered in antisynthetase syndrome, and may thus be involved in pathologic myonuclear actin aggregation. In addition, we have identified a typical topographic distribution of necrotic myofibers predominantly located at the periphery of muscle fascicles accompanied by inflammation and destruction of the perimysial connective tissue. Conclusion: Antisynthetase syndrome–associated myositis is characterized by distinctive myonuclear actin filament inclusions, including rod formations and a typical necrotizing perimysial myositis. This supports the hypothesis that antisynthetase syndrome–associated myositis is unique and should not be grouped among dermatomyositis, polymyositis, sporadic inclusion body myositis, necrotizing autoimmune myositis, or nonspecific myositis. Classification of evidence: This study provides Class II evidence that for patients with IIMs, the presence of myonuclear actin filament inclusions accurately identifies patients with antisynthetase syndrome–associated myositis (sensitivity 81%, specificity 100%).

Delayed contrast-enhanced MRI of the coronary artery wall in takayasu arteritis.

Background Takayasu arteritis (TA) is a rare form of chronic inflammatory granulomatous arteritis of the aorta and its major branches. Late gadolinium enhancement (LGE) with magnetic resonance imaging (MRI) has demonstrated its value for the detection of vessel wall alterations in TA. The aim of this study was to assess LGE of the coronary artery wall in patients with TA compared to patients with stable CAD. Methods We enrolled 9 patients (8 female, average age 46±13 years) with proven TA. In the CAD group 9 patients participated (8 male, average age 65±10 years). Studies were performed on a commercial 3T whole-body MR imaging system (Achieva; Philips, Best, The Netherlands) using a 3D inversion prepared navigator gated spoiled gradient-echo sequence, which was repeated 34–45 minutes after low-dose gadolinium administration. Results No coronary vessel wall enhancement was observed prior to contrast in either group. Post contrast, coronary LGE on IR scans was detected in 28 of 50 segments (56%) seen on T2-Prep scans in TA and in 25 of 57 segments (44%) in CAD patients. LGE quantitative assessment of coronary artery vessel wall CNR post contrast revealed no significant differences between the two groups (CNR in TA: 6.0±2.4 and 7.3±2.5 in CAD; p = 0.474). Conclusion Our findings suggest that LGE of the coronary artery wall seems to be common in patients with TA and similarly pronounced as in CAD patients. The observed coronary LGE seems to be rather unspecific, and differentiation between coronary vessel wall fibrosis and inflammation still remains unclear.

Differential roles of hypoxia and innate immunity in juvenile and adult dermatomyositis

Dermatomyositis (DM) can occur in both adults and juveniles with considerable clinical differences. The links between immune-mediated mechanisms and vasculopathy with respect to development of perifascicular pathology are incompletely understood. We investigated skeletal muscle from newly diagnosed, treatment-naïve juvenile (jDM) and adult dermatomyositis (aDM) patients focusing on hypoxia-related pathomechanisms, vessel pathology, and immune mechanisms especially in the perifascicular region. Therefore, we assessed the skeletal muscle biopsies from 21 aDM, and 15 jDM patients by immunohistochemistry and electron microscopy. Transcriptional analyses of genes involved in hypoxia, as well as in innate and adaptive immunity were performed by quantitative Polymerase chain reaction (qPCR) of whole tissue cross sections including perifascicular muscle fibers.Through these analysis, we found that basic features of DM, like perifascicular atrophy and inflammatory infiltrates, were present at similar levels in jDM and aDM patients. However, jDM was characterized by predominantly hypoxia-driven pathology in perifascicular small fibers and by macrophages expressing markers of hypoxia. A more pronounced regional loss of capillaries, but no relevant activation of type-1 Interferon (IFN)-associated pathways was noted. Conversely, in aDM, IFN-related genes were expressed at significantly elevated levels, and Interferon-stimulated gene (ISG)15 was strongly positive in small perifascicular fibers whereas hypoxia-related mechanisms did not play a significant role.In our study we could provide new molecular data suggesting a conspicuous pathophysiological ‘dichotomy’ between jDM and aDM: In jDM, perifascicular atrophy is tightly linked to hypoxia-related pathology, and poorly to innate immunity. In aDM, perifascicular atrophy is prominently associated with molecules driving innate immunity, while hypoxia-related mechanisms seem to be less relevant.

Diagnostic value and clinical laboratory associations of antibodies against recombinant ribosomal P0, P1 and P2 proteins and their native heterocomplex in a Caucasian cohort with systemic lupus erythematosus

IntroductionIn this study, we sought to determine the diagnostic value and clinical laboratory associations of autoantibodies against recombinant ribosomal P0, P1 and P2 proteins and their native heterocomplex in systemic lupus erythematosus (SLE).MethodsAutoantibodies against recombinant ribosomal P proteins (aRibPR0, aRibPR1 and aRibPR2) and antibodies against native ribosomal P heterocomplex (aRibPNH) were determined in sera from patients with SLE (n = 163), systemic sclerosis (n = 66), Sjögrens syndrome (n = 54), rheumatoid arthritis (n = 90) and healthy donors (n = 100) using enzyme-linked immunosorbent assay. Test results were correlated to medical records, including the American College of Rheumatology criteria, the Systemic Lupus Erythematosus Disease Activity Index 2000, laboratory data and medications of all SLE patients.ResultsSensitivities of 22.0% for aRibPR0, 14.9% for aRibPR2, 14.3% for aRibPNH and 10.7% for aRibPR1 were obtained at a specificity of 99%. The assay for aRibPR0 detection demonstrated the best performance in receiver-operating characteristics analysis, with aRibPR0 detectable in 10% of anti-Smith antibody and anti-double-stranded DNA-negative sera at a specificity of 100%. ARibPR0 positivity was associated with lymphocytopenia. ARibPR1+ patients had significantly higher γ-glutamyl transpeptidase (GGT) levels than their aRibPR1- counterparts. No specific damage occurred in aRibP+ lupus patients compared with a group of age-, sex- and nephritis-matched aRibP- lupus patients within 3 years.ConclusionsThe determination of antibodies against ribosomal P proteins improves the diagnosis of SLE and should therefore be implemented in upcoming criteria for the diagnosis or classification of SLE. High titers of aRibPR0 can be associated with lymphocytopenia, and high titers of aRibPR1 can be associated with elevated GGT levels. So far, there is no evidence for a prognostic value of aRibPs for damage.

Unmasking of autoreactive CD4 T cells by depletion of CD25 regulatory T cells in systemic lupus erythematosus

Objective Autoreactive CD4 T cells specific for nuclear peptide antigens play an important role in tolerance breakdown during the course of systemic lupus erythematosus (SLE). However, reliable detection of these cells is limited due to their low frequency in peripheral blood. The authors assess autoreactive CD4 T cells in a representative SLE collective (n=38) by flow cytometry and study the influence of regulatory T cells (Treg) on their antigenic challenge. Methods CD4 T-cell responses were determined according to intracellular CD154 expression induced after 6-h short-term in-vitro stimulation with the SLE-associated autoantigen SmD1(83-119). To clarify the influence of Treg on the activation of autoreactive CD4 T cells, CD25 Treg were depleted by magnetic activated cell sorting before antigen-specific stimulation in selected experiments. Results In the presence of Treg, autoreactive CD4 T-cell responses to SmD1(83-119) were hardly observable. However, Treg removal significantly increased the frequency of detectable SmD1(83-119)-specific CD4 T cells in SLE patients but not in healthy individuals. Consequently, by depleting Treg the percentage of SmD1(83-119)-reactive SLE patients increased from 18.2% to 63.6%. This unmasked autoreactivity of CD4 T cells correlated with the disease activity as determined by the SLE disease activity index (p=0.005*, r=0.779). Conclusions These data highlight the pivotal role of the balance between autoreactive CD4 T cells and CD25 Treg in the dynamic course of human SLE. Analysing CD154 expression in combination with a depletion of CD25 Treg, as shown here, may be of further use in approaching autoantigen-specific CD4 T cells in SLE and other autoimmune diseases.

The lymphoid follicle variant of dermatomyositis

Objective: To investigate the clinical and morphologic spectrum of early adult–onset dermatomyositis (DM), an inflammatory disease that affects small vessels of the muscle and the skin. Methods: Histologic evaluation of frozen muscle samples was employed to visualize the cellular organization of ectopic lymphoid structures in muscle biopsies obtained from 2 patients diagnosed with DM. Clinical presentation and morphologic features, as well as treatment and follow-up, were assessed and documented. Electron microscopy was used to confirm the light microscopic diagnosis of DM. Clonality analysis of B-cell populations using PCR was performed. Results: Muscle biopsy of both patients fulfilled the morphologic European Neuromuscular Centre criteria of DM. Analyses of muscle biopsy samples revealed ectopic lymphoid follicle-like structures that showed a remarkable similarity to secondary lymphoid organs (SLOs) with distinct T- and B-cell compartmentalization. Our 2 patients exhibited an atypical and mild clinical presentation and responded favorably to therapy. Conclusions: The clinical and histopathologic features of DM can be atypical, and the presence of SLOs is not inevitably linked to an unfavorable prognosis.

Responders to cyclophosphamide: results of a single-centre analysis among systemic sclerosis patients

Interstitial lung fibrosis significantly contributes to morbidity and mortality in systemic sclerosis (SSc),1 but only a few established treatment options exist.2 Cyclophosphamide (CYC)3 is one of the effective options for interstitial lung disease and skin thickening.4 5 However, not all patients respond to this medication and based on the clinical routine practice in one centre, there has been no analysis using reduced intravenous cyclophosphamide (800–1200 mg monthly). 6,–,8 Therefore, we evaluated the response to intravenous cyclophosphamide treatment in 39 patients with SSc in our department. Responders were defined by any of the three outcome parameters: the modified Rodnan skin score (mRSS; responders: decrease by ≥5/51 points), forced vital capacity (FVC; responders: increase or no decline >10%) or diffusing lung capacity for carbon monoxide (DLCO; responders: increase or no decline >10%). Lung function test (LFT) denominated responders that fulfilled both …

Adulter Morbus Still mit Kleingefäßvaskulitis

This article presents a particularly severe case of adult onset Stills disease aggravated by small vessel vasculitis. A satisfactory therapy was concluded 1.5 years after onset of the disease. The small vessel vasculitis was difficult to treat: methotrexate (MTX), cyclophosphamide and rituximab were not sufficiently effective. Tocilizumab in combination with intravenous immunoglobulin (IVIG) induced remission and maintenance therapy was carried out with tocilizumab.