Myeloperoxidase-specific antineutrophil cytoplasmic antibody-associated vasculitis

Myeloperoxidase (MPO)-specific antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (MPO-ANCA-associated vasculitis) is one of two major ANCA-associated vasculitis variants characterised by systemic necrotising vasculitis with few or no immune deposits. MPO-ANCA-associated vasculitis predominantly affects small blood vessels and, in contrast to its counterpart proteinase 3-ANCA-associated vasculitis, is generally not associated with granulomatous inflammation. The kidneys and lungs are the most commonly affected organs. The pathogenesis of MPO-ANCA-associated vasculitis is characterised by loss of tolerance to the neutrophil enzyme MPO. This loss of tolerance leads to a chronic immunopathological response where neutrophils become both the target and effector of autoimmunity. MPO-ANCA drives neutrophil activation, leading in turn to tissue and organ damage. Clinical trials have improved the therapeutic approach to MPO-ANCA-associated vasculitis. However, there remains substantial unmet need regarding relapse frequency, toxicity of current treatment, and long-term morbidity. In this Series paper, we present the current state of research regarding pathogenesis, diagnosis, and treatment of MPO-ANCA-associated vasculitis.

Advanced portable micro-SORS prototype coupled with SERDS for heritage science

We investigate the subsurface composition of turbid materials at the micro scale by means of a portable non-invasive technique, micro-spatially offset Raman spectroscopy (micro-SORS), combined with shifted excitation Raman difference spectroscopy (SERDS). This combination enables the microscale layer analysis and allows to deal effectively with highly fluorescing samples as well as ambient light, all in a form of an in-house portable prototype device optimised for applications in heritage science. The instrument comprises ability to simultaneously collect multiple spectra by means of an optical fibre bundle, thus reducing the dead time and simplifying the ease of deployment of the technique. The performance of the synergy between micro-SORS and 785 nm SERDS dual-wavelength diode laser is demonstrated on a stratified mock-up painting samples including highly fluorescing painted layers. This instrumental approach could be ground-breaking in heritage science, due to the largely unmet need of analysing the molecular composition of subsurface of artworks non-invasively and in situ, and in the presence of fluorescent background and ambient light. Moreover, many other fields are expected to benefit from this technological advancement such as solar energy, forensic and food analytical areas.

Association between lung function and dyspnoea and its variation in the multinational Burden of Obstructive Lung Disease (BOLD) study

BACKGROUND

Dyspnoea is a common symptom of respiratory disease. However, data on its prevalence in general populations and its association with lung function are limited and are mainly from high-income countries. The aims of this study were to estimate the prevalence of dyspnoea across several world regions, and to investigate the association of dyspnoea with lung function.

METHODS

Dyspnoea was assessed, and lung function measured in 25,806 adult participants of the multinational Burden of Obstructive Lung Disease study. Dyspnoea was defined as ≥2 on the modified Medical Research Council (mMRC) dyspnoea scale. The prevalence of dyspnoea was estimated for each of the study sites and compared across countries and world regions. Multivariable logistic regression was used to assess the association of dyspnoea with lung function in each site. Results were then pooled using random-effects meta-analysis.

RESULTS

The prevalence of dyspnoea varied widely across sites without a clear geographical pattern. The mean prevalence of dyspnoea was 13.7 % (SD=8.2 %), ranging from 0 % in Mysore (India) to 28.8 % in Nampicuan-Talugtug (Philippines). Dyspnoea was strongly associated with both spirometry restriction (FVC

CONCLUSION

The prevalence of dyspnoea varies substantially across the world and is strongly associated with lung function impairment. Using the mMRC scale in epidemiological research should be discussed.

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Key Words

• Breathlessness
• Dyspnoea
• Lung function
• Spirometry

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MESH Headings Collapse

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Invasiveness of decompression surgery affects modeled lumbar spine kinetics in patients with degenerative spondylolisthesis

Introduction: The surgical treatment of degenerative spondylolisthesis with accompanying spinal stenosis focuses mainly on decompression of the spinal canal with or without additional fusion by means of a dorsal spondylodesis. Currently, one main decision criterion for additional fusion is the presence of instability in flexion and extension X-rays. In cases of mild and stable spondylolisthesis, the optimal treatment remains a subject of ongoing debate. There exist different opinions on whether performing a fusion directly together with decompression has a potential benefit for patients or constitutes overtreatment. As X-ray images do not provide any information about internal biomechanical forces, computer simulation of individual patients might be a tool to gain a set of new decision criteria for those cases. Methods: To evaluate the biomechanical effects resulting from different decompression techniques, we developed a lumbar spine model using forward dynamic-based multibody simulation (FD_MBS). Preoperative CT data of 15 patients with degenerative spondylolisthesis at the level L4/L5 who underwent spinal decompression were identified retrospectively. Based on the segmented vertebrae, 15 individualized models were built. To establish a reference for comparison, we simulated a standardized flexion movement (intact) for each model. Subsequently, we performed virtual unilateral and bilateral interlaminar fenestration (uILF, bILF) and laminectomy (LAM) by removing the respective ligaments in each model. Afterward, the standardized flexion movement was simulated again for each case and decompression method, allowing us to compare the outcomes with the reference. This comprehensive approach enables us to assess the biomechanical implications of different surgical approaches and gain valuable insights into their effects on lumbar spine functionality. Results: Our findings reveal significant changes in the biomechanics of vertebrae and intervertebral discs (IVDs) as a result of different decompression techniques. As the invasiveness of decompression increases, the moment transmitted on the vertebrae significantly rises, following the sequence intact ➝ uILF ➝ bILF ➝ LAM. Conversely, we observed a reduction in anterior-posterior shear forces within the IVDs at the levels L3/L4 and L4/L5 following LAM. Conclusion: Our findings showed that it was feasible to forecast lumbar spine kinematics after three distinct decompression methods, which might be helpful in future clinical applications.

In vivo characterization of the novel ebolavirus Bombali virus suggests a low pathogenic potential for humans

Ebolaviruses cause outbreaks of haemorrhagic fever in Central and West Africa. Some members of this genus such as Ebola virus (EBOV) are highly pathogenic, with case fatality rates of up to 90%, whereas others such as Reston virus (RESTV) are apathogenic for humans. Bombali virus (BOMV) is a novel ebolavirus for which complete genome sequences were recently found in free-tailed bats, although no infectious virus could be isolated. Its pathogenic potential for humans is unknown. To address this question, we first determined whether proteins encoded by the available BOMV sequence found in Chaerephon pumilus were functional in in vitro assays. The correction of an apparent sequencing error in the glycoprotein based on these data then allowed us to generate infectious BOMV using reverse genetics and characterize its infection of human cells. Furthermore, we used HLA-A2-transgenic, NOD-scid-IL-2γ receptor-knockout (NSG-A2) mice reconstituted with human haematopoiesis as a model to evaluate the pathogenicity of BOMV in vivo in a human-like immune environment. These data demonstrate that not only does BOMV show a slower growth rate than EBOV in vitro, but it also shows low pathogenicity in humanized mice, comparable to previous studies using RESTV. Taken together, these findings suggest a low pathogenic potential of BOMV for humans.

Elevated rates of dietary generalization in eusocial lineages of the secondarily herbivorous bees

BACKGROUND

Within the Hymenoptera, bees are notable for their relationship with flowering plants, being almost entirely dependent on plant pollen and nectar. Though functionally herbivorous, as a result of their role as pollinators, bees have received comparatively little attention as models for insect herbivory. Bees often display dietary specialization, but quantitative comparison against other herbivorous insects has not previously been conducted.

RESULTS

In the most comprehensive analysis to date for 860 bee species, dietary specialization amounted to 50.1% of studied species collecting pollen from between 1 and 2 botanical families with a relatively long tail of dietary generalists, with 11.1% of species collecting from more than 10 botanical families. This distribution deviated from the truncated Pareto distribution of dietary breadth seen in other herbivorous insect lineages. However, this deviation was predominantly due to eusocial bee lineages, which show a range of dietary breadths that conformed to a normal distribution, while solitary bees show a typical truncated distribution not strongly different from other herbivorous insects. We hypothesize that the relatively low level of dietary specialization in bees as a whole reflects the relaxation of the constraints typically observed in herbivorous insects with a comparatively reduced importance of plant chemistry and comparatively increased importance of phenology and foraging efficiency. The long flight periods of eusocial bees that are necessary to allow overlapping generations both allows and necessitates the use of multiple flowering resources, whereas solitary bees with short flight periods have more limited access to varied resources within a constrained activity period.

CONCLUSIONS

Collectively, solitary bees show slightly lower specialization compared to other herbivorous insects, possibly due to their balanced relationship with plants, rather than direct antagonism such as seen in the direct consumption of plant tissues. An additional factor may be the mediocre diversity of bees at low latitudes combined with low levels of dietary specialization, whereas these areas typically display a high rate of specialization by herbivorous insects in general. Though the most important factors structuring dietary specialization in bees appear to differ from many other herbivorous insects, solitary bees show a surprisingly similar overall pattern of dietary specialization.

Dynamic ventral disc contraction is necessary for Giardia attachment and host pathology

Giardia lamblia is a common parasitic protist that infects the small intestine and causes giardiasis, resulting in diarrhea, vomiting, weight loss, and malabsorption. Giardiasis leads to cellular damage, including loss of microvilli, disruption of tight junctions, impaired barrier function, enzyme inhibition, malabsorption, and apoptosis. In the host, motile Giardia trophozoites attach to the duodenal microvilli using a unique microtubule organelle called the ventral disc. Despite early observations of disc-shaped depressions in microvilli after parasite detachment, little is known about disc-mediated attachment mechanisms and there little direct evidence showing that parasite attachment causes cellular damage. However, advancements in in vitro organoid models of infection and genetic tools have opened new possibilities for studying molecular mechanisms of attachment and the impact of attachment on the host. Through high-resolution live imaging and a novel disc mutant, we provide direct evidence for disc contraction during attachment, resolving the long-standing controversy of its existence. Specifically, we identify three types of disc movements that characterize contraction, which in combination result in a decrease in disc diameter and volume. Additionally, we investigate the consequences of attachment and disc contractility using an attachment mutant that has abnormal disc architecture. In a human organoid model, we demonstrate that this mutant has a limited ability to break down the epithelial barrier as compared to wild type. Based on this direct evidence, we propose a model of attachment that incorporates disc contraction to generates the forces required for the observed "grasping" of trophozoites on the host epithelium. Overall, this work highlights the importance of disc contractility in establishing and maintaining parasite attachment, leading to intestinal barrier breakdown.

Skin microbiota secretomes modulate cutaneous innate immunity against Borrelia burgdorferi s.s

In Lyme borreliosis, the skin constitutes a major interface for the host, the bacteria and the tick. Skin immunity is provided by specialized immune cells but also by the resident cells: the keratinocytes and the fibroblasts. Discoveries on the role of the microbiome in the modulation of skin inflammation and immunity have reinforced the potential importance of the skin in vector-borne diseases. In this study, we analyzed in vitro the interaction of human primary keratinocytes and fibroblasts with Borrelia burgdorferi sensu stricto N40 in presence or absence of bacterial commensal supernatants. We aimed to highlight the role of resident skin cells and skin microbiome on the inflammation induced by B. burgdorferi s.s.. The secretomes of Staphylococcus epidermidis, Corynebacterium striatum and Cutibacterium acnes showed an overall increase in the expression of IL-8, CXCL1, MCP-1 and SOD-2 by fibroblasts, and of IL-8, CXCL1, MCP-1 and hBD-2 in the undifferentiated keratinocytes. Commensal bacteria showed a repressive effect on the expression of IL-8, CXCL1 and MCP-1 by differentiated keratinocytes. Besides the inflammatory effect observed in the presence of Borrelia on all cell types, the cutaneous microbiome appears to promote a rapid innate response of resident skin cells during the onset of Borrelia infection.

When natural antibodies become pathogenic: autoantibodies targeted against G protein-coupled receptors in the pathogenesis of systemic sclerosis

Systemic sclerosis (SSc) is a chronic, multisystem connective tissue, and autoimmune disease with the highest case-specific mortality and complications among rheumatic diseases. It is characterized by complex and variable features such as autoimmunity and inflammation, vasculopathy, and fibrosis, which pose challenges in understanding the pathogenesis of the disease. Among the large variety of autoantibodies (Abs) present in the sera of patients suffering from SSc, functionally active Abs against G protein-coupled receptors (GPCRs), the most abundant integral membrane proteins, have drawn much attention over the last decades. These Abs play an essential role in regulating the immune system, and their functions are dysregulated in diverse pathological conditions. Emerging evidence indicates that functional Abs targeting GPCRs, such as angiotensin II type 1 receptor (AT1R) and the endothelin-1 type A receptor (ETAR), are altered in SSc. These Abs are part of a network with several GPCR Abs, such as those directed to the chemokine receptors or coagulative thrombin receptors. In this review, we summarize the effects of Abs against GPCRs in SSc pathologies. Extending the knowledge on pathophysiological roles of Abs against GPCRs could provide insights into a better understanding of GPCR contribution to SSc pathogenesis and therefore help in developing potential therapeutic strategies that intervene with pathological functions of these receptors.

Corrigendum to "Integration of datasets to provide insights about households' natural gas expenditure as trigger to building stock decarbonisation" [Heliyon 9(4) (April 2023) e14922]

[This corrects the article DOI: 10.1016/j.heliyon.2023.e14922.].

Implementation of 2D Barcode Medication Labels and Smart Pumps in Pediatric Acute Care: Lessons Learned

BACKGROUND

In pediatric intensive care, prescription, administration, and interpretation of drug doses are weight dependent. The use of standardized concentrations simplifies the preparation of drugs and increases safety. For safe administration as well as easy interpretation of intravenous drug dosing regimens with standardized concentrations, the display of weight-related dose rates on the infusion device is of pivotal significance.

OBJECTIVES

We report on challenges in the implementation of a new information technology-supported medication workflow. The workflow was introduced on eight beds in the pediatric heart surgery intensive care unit as well as in the pediatric anesthesia at the University of Bonn Medical Center. The proposed workflow utilizes medication labels generated from prescription data from the electronic health record. The generated labels include a two-dimensional barcode to transfer data to the infusion devices.

METHODS

Clinical and technical processes were agilely developed. The reliability of the system under real-life conditions was monitored. User satisfaction and potential for improvement were assessed. In addition, a structured survey among the nursing staff was performed. The questionnaire addressed usability as well as the end-users' perception of the effects on patient safety.

RESULTS

The workflow has been applied 44,111 times during the pilot phase. A total of 114 known failures in the technical infrastructure were observed. The survey showed good ratings for usability and safety (median "school grade" 2 or B for patient safety, intelligibility, patient identification, and handling). The medical management of the involved acute care facilities rated the process as clearly beneficial regarding patient safety, suggesting a rollout to all pediatric intensive care areas.

CONCLUSION

A medical information technology-supported medication workflow can increase user satisfaction and patient safety as perceived by the clinical end-users in pediatric acute care. The successful implementation benefits from an interdisciplinary team, active investigation of possible associated risks, and technical redundancy.

Autoantibodies targeting G protein-coupled receptors: An evolving history in autoimmunity. Report of the 4th international symposium

G protein-coupled receptors (GPCR) are involved in various physiological and pathophysiological processes. Functional autoantibodies targeting GPCRs have been associated with multiple disease manifestations in this context. Here we summarize and discuss the relevant findings and concepts presented in the biennial International Meeting on autoantibodies targeting GPCRs (the 4th Symposium), held in Lübeck, Germany, 15-16 September 2022. The symposium focused on the current knowledge of these autoantibodies' role in various diseases, such as cardiovascular, renal, infectious (COVID-19), and autoimmune diseases (e.g., systemic sclerosis and systemic lupus erythematosus). Beyond their association with disease phenotypes, intense research related to the mechanistic action of these autoantibodies on immune regulation and pathogenesis has been developed, underscoring the role of autoantibodies targeting GPCRs on disease outcomes and etiopathogenesis. The observation repeatedly highlighted that autoantibodies targeting GPCRs could also be present in healthy individuals, suggesting that anti-GPCR autoantibodies play a physiologic role in modeling the course of diseases. Since numerous therapies targeting GPCRs have been developed, including small molecules and monoclonal antibodies designed for treating cancer, infections, metabolic disorders, or inflammatory conditions, anti-GPCR autoantibodies themselves can serve as therapeutic targets to reduce patients' morbidity and mortality, representing a new area for the development of novel therapeutic interventions.

Integration of datasets to provide insights about households’ natural gas expenditure as trigger to building stock decarbonisation

Deep-renovations measures are identified as possible solutions to support European Union's natural gas phase-out and fuel independency. However, it has been difficult to increase renovation rates (about 1% per year), and previous studies have recognized socio-economic barriers as one of the reasons for that. Then, integrated (techno-socio-economic) datasets are vital to support building policy measures that circumvent the negative consequences of high gas prices. This paper's main objective is to develop and to test a methodology that merges two data sources: the European Union Statistics on Income and Living Conditions and the Household Budget Survey in order to create an integrated techno-socio-economic dataset. The following research questions are answered: What is the replicable methodology for merging both datasets in order to create an accurate statistical model? What can we learn about household savings and natural gas expenditures of household types characterised by ownership status and dwelling type? The modelling results show that the developed logistic regression model presented an accuracy of 77% using 2015 data from Spain. The explorative statistical analysis showed that the owner-occupied single-family houses predominate in the highest natural gas expenditure quintiles, while the rented single-family houses in the lowest quintiles, indicating that ownership status may have a stronger influence on the natural gas expenditure than building type. The mean annual household savings are negative, an evidence of households' budget restrictions to finance deep renovation activities. As a conclusion, the generated techno-socio-economic synthetic dataset provides useful information about the relation between household budget restrictions, natural gas expenditure and potential investment on deep renovation. Based on the generated dataset, it is also concluded that higher natural gas prices alone are not sufficient to stimulate deep renovations. For boosting renovation activities, the design of financing and incentive schemes should be end-user targeted considering the households' heterogeneity. Then, the definition of households' profiles should include ownership status and other socio-economic parameters not only dwelling type. This work prepares the ground for setting techno-socio-economic databases that can be used to design more accurate incentives and financing schemes to accelerate European building stock decarbonisation and fossil fuel independency.

Vibrationally Resolved Inner-Shell Photoexcitation of the Molecular Anion C2. Chemphyschem 2023:e202300061. [PMID: 36815408 DOI: 10.1002/cphc.202300061] [Citation(s) in RCA: 0] [Impact Index Per Article: 0]

Carbon 1s core-hole excitation of the molecular anion C₂ ^- has been experimentally studied at high resolution by employing the photon-ion merged-beams technique at a synchrotron light source. The experimental cross section for photo-double-detachment shows a pronounced vibrational structure associated with 1 σ u → 3 σ g ${1\sigma _u \to 3\sigma _g }$ and 1 σ g → 1 π u ${1\sigma _g \to 1\pi _u }$ core excitations of the C₂ ^- ground level and first excited level, respectively. A detailed Franck-Condon analysis reveals a strong contraction of the C₂ ^- molecular anion by 0.2 Å upon this core photoexcitation. The associated change of the molecule's moment of inertia leads to a noticeable rotational broadening of the observed vibrational spectral features. This broadening is accounted for in the present analysis which provides the spectroscopic parameters of the C₂ ^- 1 σ u - 1 3 σ g 2 2 Σ u + ${1\sigma _u^{ - 1} \,3\sigma _g^2 \;^2 \Sigma _u^ + }$ and 1 σ g - 1 3 σ g 2 2 Σ g + ${1\sigma _g^{ - 1} \,3\sigma _g^2 \;^2 \Sigma _g^ + }$ core-excited levels.

An integrated ion trap for the photon-ion spectrometer at PETRA III

We have added a multipole ion trap to the existing photon-ion spectrometer at PETRA III (PIPE). Its hybrid structure combines a ring-electrode trap with a segmented 16-pole trap. The interaction of gases and ions with extreme ultraviolet radiation from the beamline P04 is planned to be investigated with the newly installed multipole trap. The research focus lies on radiation-induced chemical reactions that take place in the interstellar medium or in the atmospheres of planets, including natural as well as man-made processes that are important in the Earth's atmosphere. In order to determine the mass-to-charge ratio of the stored ions as efficiently as possible, we are using an ion time-of-flight spectrometer. With this technique, all stored ions can be detected simultaneously. To demonstrate the possibilities of the trap setup, two experiments have been carried out: The photoionization of xenon and the ion-impact ionization of norbornadiene. This type of ion-impact ionization can, in principle, also take place in planetary atmospheres. In addition to ionization by photon or ion impact, chemical reactions of the trapped ions with neutral atoms or molecules in the gas phase have been observed. The operation of the trap enables us to simulate conditions similar to those in the ionosphere.

Low Concentrations of C5a Complement Receptor Antibodies Are Linked to Disease Activity and Relapse in Antineutrophil Cytoplasmic Autoantibody-Associated Vasculitis

OBJECTIVE

To examine concentrations of circulating antibodies targeting C3a and C5a complement receptors in antineutrophil cytoplasmic autoantibody (ANCA)-associated vasculitis (AAV) and analyze their association with disease activity.

METHODS

Concentrations of antibodies against C3a and C5a complement receptors (anti-C3aR and anti-C5aR) and plasma complement fragments C3a and C5a were determined in patients with AAV (n = 110; granulomatosis with polyangiitis [GPA; n = 82] or microscopic polyangiitis [MPA; n = 28]), systemic lupus erythematosus (SLE) patients as disease controls (n = 36), and healthy donors (n = 220). C3aR and C5aR expression by circulating neutrophils, monocytes, and T cells was analyzed using flow cytometry. Clinical data were assessed at time of serum sampling and during follow-up for 60 months.

RESULTS

In AAV, anti-C3aR and anti-C5aR antibodies were decreased (P = 0.0026 and P ≤ 0.0001, respectively). In remission, anti-C3aR antibody concentrations rose to values comparable to healthy donors, whereas anti-C5aR antibody concentrations did not. In GPA, anti-C5a and anti-C5aR antibody concentrations inversely correlated with each other (r = -0.6831, P = 0.0127). In newly diagnosed GPA, decreased concentrations of anti-C5aR antibodies but not anti-C3aR antibodies were associated with disease activity (P = 0.0009). Moreover, low anti-C5aR antibodies were associated with relapse in GPA (hazard ratio 3.54, P = 0.0009) and MPA (hazard ratio 4.41, P = 0.0041). The frequency of C5aR-expressing cells within T cell populations was increased in GPA (P = 0.0021 for CD4+ T cells; P = 0.0118 for CD8+ T cells), but not in MPA.

CONCLUSION

Low concentrations of anti-C5aR antibodies reflect disease activity and are associated with an increased risk for relapse in AAV.

The arthroscopic Bankart operation: a 10-year follow-up study

INTRODUCTION

Traumatic shoulder instability most frequently occurs in young people often during sports events. Currently, the arthroscopic Bankart repair is the therapy of choice in the absence of extensive glenoid bone loss and has proved to be a safe and effective procedure. Nevertheless, we see recurrence of instability-especially if new trauma happens-and further data are needed to guide the right decision-making for these often young patients. The purpose of this study was to determine the long-term outcome 10 years after arthroscopic Bankart operation in terms of satisfaction of the patient, functional result, complications, recurrent instability, and development of osteoarthritis, and to look after possible risk factors for recurrence of instability and statistical proof of these.

MATERIALS AND METHODS

Thirty-nine out of 49 patients underwent physical examination of both shoulders. We could perform a postoperative shoulder a-p X-ray in 28 patients. According to Samilson, [24] the extent of osteoarthritis was measured. The Constant score and the postoperative ROWE score were determined for both shoulders as well as the WOSI Score. In 25 cases, we calculated the ISIS Score.

RESULTS

We could reach out to 89.6% of patients and 79.6% could be physically examined. The vast majority of 95.5% are either very satisfied or satisfied with the result at the time we ended the follow-up. The mean Constant score of 95.5 reflects this result. In contrast to this, we found at the same time in 15.3% ongoing clinical signs of instability of the concerning shoulder, even though 9.1% had to be re-operated for recurrent instability in between the follow-up timeline and we found in the X-rays (57.1% of all patients) in 35.7% at least moderate and in 10.7% severe signs of osteoarthritis. The Constant score but not the ROWE score differed significantly in patients with no or mild compared to those with moderate-to-severe osteoarthritis.

CONCLUSIONS

The arthroscopic Bankart stabilization procedure showed after 10 years to be a very safe operation and to be able to produce a satisfying and functional very good long-term result-reflected by the Constant score. We assume that the extent of osteoarthritis seems to be the determining factor of the very good functional result, even though ongoing instability was present in 15.3% of the patients.

Therapy satisfaction and health literacy are key factors to improve medication adherence in systemic sclerosis

OBJECTIVE

Although medication adherence (MA) contributes to therapeutic outcome in systemic sclerosis (SSc), research data are scarce. Factors influencing MA in SSc are hardly known.

METHOD

We conducted a monocentric, cross-sectional study on 85 patients with SSc at the University of Lübeck, Germany, using the Compliance Questionnaire of Rheumatology as the main measurement tool of MA. We also used the Scleroderma Health Assessment Questionnaire, Illness Perception Questionnaire - Revised, Health Literacy Questionnaire, Lübeck Medication Satisfaction Questionnaire (a novel instrument created for this study), and patients' demographic and clinical data, to find factors contributing to MA.

RESULTS

Good MA was seen in 51.8% of patients. MA was positively associated with therapy satisfaction (p < 0.001), modified Rodnan Skin Score (p = 0.032), age (p = 0.025), intake of micronutrients (p = 0.033), number of prescribed drugs (p = 0.014), and some dimensions of health literacy. Negative associations were found for patients with weight loss attributed to SSc (p = 0.009) and the perception that the disease is caused by the patient's personality (p = 0.011) or emotional state (p = 0.037).

CONCLUSION

Although most SSc patients display good MA, non-adherence remains a major problem. Patients should be assessed for non-adherence. The factors affecting MA identified herein could help to improve therapeutic outcomes.

Both T and B cells are indispensable for the development of a PBMC transfer-induced humanized mouse model for SSc

BACKGROUND

Recently, a novel humanized mouse model for systemic sclerosis (SSc) was established by transferring peripheral blood mononuclear cells (PBMC) from patients with SSc to Rag2^-/-Il2rg^-/- immunodeficient mice. Here, we aimed to investigate the role of T and B cells in this humanized mouse model.

METHODS

T and B cells were depleted in vitro from freshly isolated PBMC using anti-CD3 and anti-CD19 magnetic microbeads, respectively. Subsequently, PBMC and T or B cell-depleted PBMC were transferred into Rag2^-/-/Il2rg^-/- mice via intraperitoneal injection. Twelve weeks after the transfer, mice were sacrificed and evaluated.

RESULTS

Mice transferred with whole PBMC from SSc patients developed systemic inflammation in the lungs, kidneys, and liver, and 6 out of 11 mice died or had to be sacrificed during the experiment. By contrast, such inflammation and death were not observed in mice transferred with corresponding T or B cell-depleted PBMC. In line with this finding, transfer with whole PBMC restored the splenic white pulp composing of human T, B, and plasma cells and led to the production of a considerable amount of human autoantibodies in recipient mice, while those immunological features were rarely observed in mice that received T or B cell-depleted PBMC. In contrast to our previous findings demonstrating a transfer of the protective effect of a B cell therapy into the mouse, treatment of SSc patients with chemical immunosuppressive drugs did not affect the pathogenicity of PBMC.

CONCLUSIONS

This study demonstrates that both T and B cells are indispensable for the pathogenesis of the PBMC transfer-induced mouse model for SSc.

Neuronal effects of glabellar botulinum toxin injections using a valenced inhibition task in borderline personality disorder

Previous studies have indicated that glabellar botulinum toxin (BTX) injections may lead to a sustained alleviation of depression. This may be accomplished by the disruption of a facial feedback loop, which potentially mitigates the experience of negative emotions. Accordingly, glabellar BTX injection can attenuate amygdala activity in response to emotional stimuli. A prototypic condition with an excess of negative emotionality and impulsivity accompanied by elevated amygdala reactivity to emotional stimuli is borderline personality disorder (BPD). In order to improve the understanding of how glabellar BTX may affect the processing of emotional stimuli and impulsivity, we conducted a functional magnetic resonance imaging (fMRI) study. Our hypotheses were (1) glabellar BTX leads to increased activation in prefrontal areas during inhibition performance and (2) BTX decreases amygdala activity during the processing of emotional stimuli in general. Using an emotional go-/no-go paradigm during fMRI, the interference of emotion processing and impulsivity in a sample of n = 45 women with BPD was assessed. Subjects were randomly assigned to BTX treatment or serial acupuncture (ACU) of the head. After 4 weeks, both treatments led to a reduction in the symptoms of BPD. However, BTX treatment was specifically associated with improved inhibition performance and increased activity in the motor cortex. In addition, the processing of negative emotional faces was accompanied by a reduction in right amygdala activity. This study provides the first evidence that glabellar BTX injections may modify central neurobiological and behavioural aspects of BPD. Since the control treatment produced similar clinical effects, these neurobiological findings may be specific to BTX and not a general correlate of symptomatic improvement.

Induced antibodies directed to the angiotensin receptor type 1 provoke skin and lung inflammation, dermal fibrosis and act species overarching

OBJECTIVE

To determine contributions and functions of autoantibodies (Abs) directed to the angiotensin receptor type 1 (AT1R), which are suggested to be involved in the pathogenesis of AT1R Abs-related diseases such as systemic sclerosis (SSc).

METHODS

C57BL/6J mice were immunised with membrane-embedded human AT1R or empty membrane as control. Mice deficient for CD4+ or CD8+ T cells and B cells were immunised with membrane-embedded AT1R or an AT1R peptide proposed to be a dominant T cell epitope. A monoclonal (m)AT1R Ab was generated by hybridoma technique and transferred into C57BL/6J and AT1Ra/b knockout mice. The induced phenotype was examined by histology, immunohistochemistry, immunofluorescence, apoptosis assay and ELISA. In vitro, Abs responses towards AT1R were measured in cells of different origins and species.

RESULTS

AT1R-immunised mice developed perivascular skin and lung inflammation, lymphocytic alveolitis, weak lung endothelial apoptosis and skin fibrosis accompanied by Smad2/3 signalling, not present in controls or mice deficient for CD4+ T and B cells. The AT1R peptide 149-172 provoked lung inflammation. Application of the mAT1R Ab induced skin and lung inflammation, not observed in AT1Ra/b knockout mice. In vitro, AT1R Abs activated rat cardiomyocytes and human monocytes, enhanced angiotensin II-mediated AT1R activation in AT1R-transfected HEK293 cells via AT1R binding and mAT1R Ab-activated monocytes mediated the induction of profibrotic markers in dermal fibroblasts.

CONCLUSION

Our immunisation strategy successfully induced AT1R Abs, contributing to inflammation and, possibly, to fibrosis via activation of AT1R. Therefore, AT1R Abs are valuable targets for future therapies of SSc and other AT1R Ab-related diseases.

AB0137 SERA DERIVED EXTRACELLULAR VESICLES FROM SYTEMIC SCLEROSIS PATIENT AND AUTOANTIBODIES MEDIATE PERIPHAL BLOOD MONOCYTES ACTIVATION

Background

In SSc, autoantibodies (abs) directed against G protein-coupled receptors (GPCR) are prominent and for example induce release of inflammatory and profibrotic proteins by monocytes (1-3). Increased levels of autoantibodies against angiotensin II type 1 receptor (AT1R abs) have been found in patients with renal involvement in systemic sclerosis (SSc) (4-5). The elevated amount of anti-GPCR abs is accompanied by increased secretion of extracellular vesicles (EVs) in SSc (6). The importance of EVs in the pathogenesis is also based on packing and horizontal transfer of AT1R to different tissues and immune cells, exemplary shown by activated cardiomyocytes leading to higher responsiveness to Angiotensin II of recipient cells and vessels (7). Taken together, the relevance of studying anti-GPCR abs together with GPCR-EVs in SSc pathogenesis becomes evident (8). Interestingly, CCL18 is found to be upregulated in SSc patients and suggested to be upregulated by AT1R abs (9), indicating CCL18 and CCR8 cross-talk via EVs plays an essential role in the pathogenesis of SSc.

Objectives

Unravel the immune response of peripheral blood monocytes mediated by anti-AT1R abs and EVs to gain new insights into the pathomechanism in SSc.

Methods

Human peripheral blood monocytes of healthy donors were stimulated by the endogenous AT1R ligand angiotensin II as well as by a monoclonal anti-human AT1R ab and, in comparison, by purified IgG from HD (HD IgG) versus those from SSc (SSc IgG). Further, human peripheral blood monocytes of HD were treated with EVs derived from sera of SSc patients versus sera of HD, in the presence or absence of a monoclonal recombinant anti-AT1R ab. Monoclonal AT1R ab has been generated by hybridoma technique, sequenced and recombinantly expressed in HEK cells. The specificity of AT1R abs was tested by using an AT1R blocker (telmisartan, TEL). EVs were isolated from sera by differential centrifugation to exclude large particles and microvesicles and further by one-step polymer precipitation procedure utilising ExoQuick Exosome Precipitation Solution (System Biosciences, Palo Alto, CA) and subsequent purification by size exclusion. Further, primary human peripheral blood monocytes of HD (n=6) were treated with EVs derived from sera of SSc patients (n=6) versus sera of HD (n=6), in the presence or absence of a monoclonal recombinant anti-AT1R ab. The response of the monocytes was measured via CCL18 secretion by ELISA.

Results

The recombinant monoclonal anti-human AT1R antibody induced secretion of CCL18, a profibrotic cytokine, by primary monocytes derived from HD. Similarly, the purified IgG fractions derived from SSc patients also induced an increased CCL18 release by monocytes compared to IgG fractions derived from HD. Further, complete amelioration of the AT1R ab effect on CCL18 secretion was found, when monocytic AT1R expression was blocked with TEL. In addition, antagonistic effects of Angiotensin II to the monoclonal AT1R ab were observed. In line, enhanced CCL18 secretion of human monocytes stimulated with SSc-EVs alone and together with the monoclonal AT1R ab was induced.

Conclusion

The secretion of pro-fibrotic CCL18 by human monocytes in response to a monoclonal AT1R antibody as well as to SSc IgG indicates that anti-AT1R abs are involved in the SSc pathogenesis. Further, this effect could also be due to SSc-EVs potentially presenting anti-GPCR abs to their receptors on immune cells.

References

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Disclosure of Interests

None declared

AB0028 IL-2 DEPRIVED PHENOTYPE OF FOXP3+ REGULATORY T CELLS AND PHENOTYPIC ALTERATIONS CONVENTIONAL CD4+ T CELLS IN PATIENTS WITH INFLAMMATORY MYOPATHIES AND PRIMARY SJOGREN´S SYNDROME

Background

A defect in regulatory T cell (Treg) homeostasis due to an acquired deficiency of interleukin-2 (IL-2) plays an important role in the pathogenesis of systemic lupus erythematosus (SLE).1,2 However, it is still unclear whether a defect in the Treg-IL-2 axis is also involved in other connective tissue disease such as inflammatory myopathies or primary Sjogren´s syndrome (pSS).

Objectives

The aim of our study was to investigate whether Treg from patients with poly- and dermatomyositis (PM/DM) and pSS display typical features of IL-2 deficiency in parallel to phenotypic alterations of conventional CD4+ T cell (Tcon) subsets compared to healthy controls (HC).

Methods

PBMC were isolated from patients with PM/DM (n=22) and pSS (n=17) and from age- and sex-matched HC (n=19) using gradient density centrifugation. Treg and Tcon subsets were analyzed by using multicolor flow cytometry. Mann-Whitney test was used for statistical analyses.

Results

Frequencies of FoxP3+CD127lo Treg among CD3+CD4+T cells were higher in pSS compared to PM/DM patients (p<0.001) and to HC (p<0.05). However, in both, PM/DM and pSS patients, frequencies of CD25+ cells among FoxP3+CD127lo Treg were significantly lower compared to HC (PM/DM: p<0.05, pSS: p<0.0001), while the frequencies of Helios+ cells among the CD25- Treg subset were substantially higher in pSS patients compared to DM/PM and HC (both p<0.001). Conversely, we found lower frequencies of CXCR5+ follicular Treg only in PM/DM patients (p<0.05). In parallel, there were higher frequencies of CD45RO+CCR7- effector/memory cells (p<0.01) and of Ki67+ proliferating cells (p<0.05) among CD3+CD4+FoxP3- Tcon in pSS patients compared to HC, which was not observed in PM/DM patients.

Conclusion

The loss of the CD25+ Treg subset in PM/DM and pSS patients is similar to previous findings in SLE patients1 and represents a hallmark of IL-2 deficiency. This suggests that shortage of IL-2 is pathophysiologically relevant also in PM/DM and pSS providing a rationale for low-dose IL-2 therapy in these diseases. In addition, activation and expansion of effector/memory Tcon appears to be more pronounced in pSS compared to PM/DM. The different distribution of Treg and of Tcon subsets between pSS and PM/DM patients might reflect differences in the availability of IL-2 and in the regulation of Tcon responses in these diseases.

References

[1]von Spee-Mayer C, Siegert E, Abdirama D, et al. Low-dose interleukin-2 selectively corrects regulatory T cell defects in patients with systemic lupus erythematosus. Ann Rheum Dis. 2016; 75; 1407–1415.

[2]Humrich JY, von Spee-Mayer C, Siegert E, et al. Low-dose interleukin-2 therapy in refractory systemic lupus erythematosus: an investigator-initiated, single-centre phase 1 and 2a clinical trial. Lancet Rheumatol. 2019; 1; e44-e54

Disclosure of Interests

Luisa R. Monne: None declared, Sara Comduehr: None declared, Fynn Gerlach: None declared, Antje Müller: None declared, Gabriela Riemekasten: None declared, Jens Y. Humrich Speakers bureau: GSK, AstraZeneca, Pfizer, BMS, UCB, MSD, AbbVie, Consultant of: GSK, AstraZeneca, ILTOO Pharma, Selecta Biosciences, Janssen-Cilag, Grant/research support from: Sanofi