Single-cell microbiota phenotyping reveals distinct disease and therapy-associated signatures in Crohn's disease.

IgA-coated fractions of the intestinal microbiota of Crohn's disease (CD) patients have been shown to contain taxa that hallmark the compositional dysbiosis in CD microbiomes. However, the correlation between other cellular properties of intestinal bacteria and disease has not been explored further, especially for features that are not directly driven by the host immune-system, e.g.

Age-stratification reveals age-specific intestinal microbiota signatures in juvenile idiopathic arthritis.

Objective: Juvenile Idiopathic Arthritis (JIA) comprises diverse chronic inflammatory conditions driven by malfunction of the immune system. The intestinal microbiota is considered a crucial environmental factor correlating with chronic inflammatory diseases, and for JIA certain alterations in the microbiota have already been described.

Methods: Here, we have characterized intestinal microbiota samples from 54 JIA patients and 38 pediatric healthy controls by conventional 16S rRNA sequencing and by single-cell analysis for phenotypic features by multi-parameter microbiota flow cytometry (mMFC), which complements the population-based taxonomic profiling with the characterization of individual bacterial cells.

Prophylactic antibodies inhibit spike-specific T and B cell responses after COVID-19 vaccination.

Active and passive immunization is used in high-risk patients to prevent severe courses of COVID-19, but the impact of prophylactic neutralizing antibodies on the immune reaction to the mRNA vaccines has remained enigmatic. Here we show that CD4 T and B cell responses to Spikevax booster immunization are suppressed by the therapeutic antibodies Casirivimab and Imdevimab. B cell and T cell responses were significantly induced in controls but not in antibody-treated patients.

[Autoantibody diagnostics in idiopathic inflammatory myopathy].

Idiopathic inflammatory myopathy (IIM) is a group of rare and heterogeneous systemic diseases that manifest not only in the muscles but also in the skin, joints, and lungs. Initial symptoms can be isolated and variable and thus the diagnosis poses challenges to various specialist groups. As autoantibodies are sometimes the only specific findings that lead to the diagnosis and appropriate treatment, basic knowledge of them is essential.

Performance of commercial SARS-CoV-2 wild-type and Omicron BA.1 antibody assays compared with pseudovirus neutralization tests.

Background: Commercially available ELISA-based antibody tests are used to approximate vaccination success against SARS-CoV-2 in at-risk patients, but it is unclear whether they correlate with neutralization of the Omicron variant.

Methods: 269 serum samples of a cohort of 44 non-immunosuppressed participants and 65 MTX-treated rheumatic patients taken before and after COVID-19 booster vaccinations were measured using COVID-19 antibody testing systems with wild-type and Omicron BA.1 antigens developed by three different manufacturers (surrogate virus neutralization test cPass, and binding antibody tests QuantiVac and SeraSpot), as well as with a pseudovirus neutralization test (pVNT).

Association between type I interferon pathway activation and clinical outcomes in rheumatic and musculoskeletal diseases: a systematic literature review informing EULAR points to consider.

Background: Type I interferons (IFN-I) contribute to a broad range of rheumatic and musculoskeletal diseases (RMDs). Compelling evidence suggests that the measurement of IFN-I pathway activation may have clinical value. Although several IFN-I pathway assays have been proposed, the exact clinical applications are unclear.

Type I interferon pathway assays in studies of rheumatic and musculoskeletal diseases: a systematic literature review informing EULAR points to consider.

Objectives: To systematically review the literature for assay methods that aim to evaluate type I interferon (IFN-I) pathway activation and to harmonise-related terminology.

Methods: Three databases were searched for reports of IFN-I and rheumatic musculoskeletal diseases. Information about the performance metrics of assays measuring IFN-I and measures of truth were extracted and summarised.

Improvement of humoral immunity by repeated dose-intensified COVID-19 vaccinations in primary non- to low-responders and B cell deficient rheumatic disease patients.

Objective: To determine whether repeated, dose-intensified mRNA vaccinations against COVID-19 increase humoral immunity in previously low-responding patients with autoimmune rheumatic diseases (AIRD), including rituximab-treated and B cell depleted patients.

Methods: Of 308 AIRD patients receiving basic immunization, 98 had a low serological response against SARS-CoV-2 with a neutralizing capacity of < 70% using surrogate neutralization assay. 38 patients received a third vaccination with 30 μg BNT162b2 16 weeks after second vaccination.

Performance of Deauville Criteria in FDG-PET/CT Diagnostics of Giant Cell Arteritis.

In this retrospective study, PET/CT data from 59 patients with suspected giant cell arteritis (GCA) were reviewed using the Deauville criteria to determine an optimal cut-off between PET positivity and negativity. Seventeen standardised vascular regions were analysed per patient by three investigators blinded to clinical information. Statistical analysis included ROC curves with areas under the curve (AUC), Cohen's and Fleiss' kappa (κ) to calculate sensitivity, specificity, accuracy, and agreement.

Type of vaccine and immunosuppressive therapy but not diagnosis critically influence antibody response after COVID-19 vaccination in patients with rheumatic disease.

Objective: The development of sufficient COVID-19 vaccines has been a big breakthrough in fighting the global SARS-CoV-2 pandemic. However, vaccination effectiveness can be reduced in patients with autoimmune rheumatic diseases (AIRD). The aim of this study was to identify factors that lead to a diminished humoral vaccination response in patients with AIRD.

SIGLEC-1 in Systemic Sclerosis: A Useful Biomarker for Differential Diagnosis.

Systemic Sclerosis (SSc) is a clinically heterogeneous disease that includes an upregulation of type I interferons (IFNs). The aim of this observational study was to investigate the IFN-regulated protein Sialic Acid−Binding Ig-like Lectin 1 (SIGLEC-1) as a biomarker for disease phenotype, therapeutic response, and differential diagnosis in SSc. Levels of SIGLEC-1 expression on monocytes of 203 SSc patients were determined in a cross-sectional and longitudinal analysis using multicolor flow cytometry, then compared to 119 patients with other rheumatic diseases and 13 healthy controls.

Pausing methotrexate prevents impairment of Omicron BA.1 and BA.2 neutralisation after COVID-19 booster vaccination.

Objective: The level of neutralising capacity against Omicron BA.1 and BA.2 after third COVID-19 vaccination in patients on paused or continuous methotrexate (MTX) therapy is unclear.

Optimising both disease control and glucocorticoid dosing is essential for bone protection in patients with rheumatic disease.

Objectives: Inflammatory rheumatic and musculoskeletal diseases (iRMDs) are associated with increased systemic bone loss that is mediated by chronic inflammation, treatment with glucocorticoids (GCs) and other factors. Our objective was to analyse the impact of variables that influence osteoporosis (OP) in patients with iRMD treated with GC.

Methods: Rh-GIOP (acronyme) is a prospective observational cohort study investigating bone health in consecutive patients with iRMD and current or prior GC treatment.

Contrast-enhanced CT techniques and MRI perform equally well in arthritis imaging of the hand: a prospective diagnostic accuracy study.

Objectives: To investigate the performance of dual-energy CT (DECT)-generated iodine maps (iMap) and CT subtraction (CT-S) in the detection of synovitis, tenosynovitis, and peritendonitis/paratenonitis compared to magnetic resonance imaging (MRI) using musculoskeletal ultrasound (MSUS) as standard of reference.

Methods: This IRB-approved prospective study consecutively investigated patients with undifferentiated arthritis. All patients underwent MSUS, MRI and contrast-enhanced DECT of the hand; from the latter conventional CT-S, image-based iMap (iMap-I) and raw data-based iMap (iMap-RD) were reconstructed.

Pausing methotrexate improves immunogenicity of COVID-19 vaccination in elderly patients with rheumatic diseases.

Objective: To study the effect of methotrexate (MTX) and its discontinuation on the humoral immune response after COVID-19 vaccination in patients with autoimmune rheumatic diseases (AIRD).

Methods: In this retrospective study, neutralising SARS-CoV-2 antibodies were measured after second vaccination in 64 patients with AIRD on MTX therapy, 31 of whom temporarily paused medication without a fixed regimen. The control group consisted of 21 patients with AIRD without immunosuppressive medication.

SIGLEC1 enables straightforward assessment of type I interferon activity in idiopathic inflammatory myopathies.

Objective: To evaluate sialic acid binding Ig-like lectin 1 (SIGLEC1) expression on monocytes by flow cytometry as a type I interferon biomarker in idiopathic inflammatory myopathies (IIM).

Methods: We performed a retrospective analysis of adult and paediatric patients with the diagnosis of IIM. SIGLEC1 expression was assessed by flow cytometry and was compared with Physician Global Assessment or Childhood Myositis Assessment Scale disease activity scores.