Objective: Individuals positive for anti-cyclic-peptide-antibodies (anti-CCP) and musculoskeletal complaints (MSK-C) are at risk for developing rheumatoid arthritis (RA). In this study we aimed to investigate factors involved in arthritis progression.
Methods: Anti-CCP2-positive individuals with MSK-C referred to a rheumatologist were recruited.
Objective: The objective of this study was to discover autoantibodies to non-modified proteins associated with the presence/absence of ACPAs in RA.
Methods: The autoantibody repertoire of 80 ACPA-negative and 80 ACPA-positive RA subjects from the Swedish population-based Epidemiological Investigation of RA (EIRA) cohort was screened using a suspension bead array built on protein fragments earlier described as autoimmunity targets. Four autoantibodies positive in the initial screening were validated in another set of EIRA samples containing 317 ACPA-positive, 302 ACPA-negative and 372 age- and sex-matched controls.
Autoantibodies to malondialdehyde (MDA) proteins constitute a subset of anti-modified protein autoantibodies in rheumatoid arthritis (RA), which is distinct from citrulline reactivity. Serum anti-MDA IgG levels are commonly elevated in RA and correlate with disease activity, CRP, IL6, and TNF-α. MDA is an oxidation-associated reactive aldehyde that together with acetaldehyde mediates formation of various immunogenic amino acid adducts including linear MDA-lysine, fluorescent malondialdehyde acetaldehyde (MAA)-lysine, and intramolecular cross-linking.
View Article and Find Full Text PDFBackground And Objective: Studies of autoimmunity and anti-citrullinated protein antibodies (ACPA) in idiopathic pulmonary fibrosis (IPF) have been confined to investigations of anti-cyclic citrullinated peptide (anti-CCP) antibodies which utilize synthetic peptides as surrogate markers for in vivo citrullinated antigens. We studied immune activation by analysing the prevalence of in vivo anti-modified protein antibodies (AMPA) in IPF.
Methods: We included patients with incident and prevalent IPF (N = 120), sex and smoking-matched healthy controls (HC) (N = 120) and patients with RA (N = 104).
Objective: The lung is implicated as a site for breach of tolerance prior to onset of seropositive rheumatoid arthritis (RA). To substantiate this, we investigated lung-resident B cells in bronchoalveolar lavage (BAL) samples from untreated early RA patients and anti-citrullinated protein antibody (ACPA)-positive individuals at risk for developing RA.
Methods: Single B cells (n = 7,680) were phenotyped and isolated from BAL samples from individuals at risk of RA (n = 3) and at RA diagnosis (n = 9).
Background: The COVID-19 pandemic resulted in a complete nationwide lockdown on March 24, 2020. The months of April and May had stringent lockdown measures followed by a gradual loosening of restrictions in a graded manner.
Methods: This observational study was performed in the emergency department (ED) of a tertiary hospital in south India triage Priority 1 and Priority 2 patients presented during the COVID-19 lockdown and unlock periods spanning from April 2020 to August 2020.
Background: There is a need for biomarker to identify patients "at risk" for rheumatoid arthritis (risk-RA) and to better predict the therapeutic response and in this study we tested the hypothesis that novel native and citrullinated heterogeneous nuclear ribonucleoprotein (hnRNP)-DL autoantibodies could be possible biomarkers.
Methods: Using protein macroarray and ELISA, epitope recognition against hnRNP-DL was analysed in sera from different developed RA disease and diagnosed SLE patients. Toll-like receptor (TLR) 7/9 and myeloid differentiation primary response gene 88 (MyD88)-dependency were studied in sera from murine disease models.
Objectives: Our knowledge about the effect of tocilizumab (TCZ) on the synovium in rheumatoid arthritis (RA) is limited. The aim of this study was to investigate the effect of TCZ on citrullination and on inflammation in the synovial tissue and in the peripheral blood.
Methods: 15 patients with RA underwent synovial biopsy before and 8 weeks after TCZ initiation.
Seropositive rheumatoid arthritis (RA) is characterized by the presence of rheumatoid factor (RF) and anti-citrullinated protein autoantibodies (ACPA) with different fine-specificities. Yet, other serum anti-modified protein autoantibodies (AMPA), e.g.
View Article and Find Full Text PDFIn this protocol, we describe a method to monitor cell migration by live-cell imaging of adherent cells. Scratching assay is a common method to investigate cell migration or wound healing capacity. However, achieving homogenous scratching, finding the optimal time window for end-point analysis and performing an objective image analysis imply, even for practiced and adept experimenters, a high chance for variability and limited reproducibility.
View Article and Find Full Text PDFIndian J Crit Care Med
February 2021
Background: Securing definitive airway with minimal complications is a challenging task for high-volume emergency departments (ED) that deal with patients with compromised airway.
Materials And Methods: We conducted a prospective observational study between September 2019 and March 2020. Cohort of adults presenting to the ED requiring rapid sequence induction (RSI) were recruited to determine the prevalence and risk factors for the development of aspiration pneumonia(AP) in patients intubated in the ED.
Background: Rheumatoid arthritis (RA)-associated anticitrullinated protein/peptide antibodies (ACPA) might originate at mucosal sites such as the lungs. We aimed to examine the relationship between the ACPA repertoire and lung abnormalities on high-resolution CT (HRCT) in patients with earlyuntreated RA.
Methods: 106 patients with newly diagnosed untreated RA were examined with HRCT of the lungs.
Objectives: (.) is discussed to be involved in triggering self-reactive immune responses. The aim of this study was to investigate the autocitrullinated prokaryotic peptidylarginine deiminase (PPAD) from .
View Article and Find Full Text PDFObjective: A 'mucosal connection' in RA presently attracts increasing attention. We recently described the occurrence of secretory antibodies to citrullinated protein (SC-ACPA) in sera from patients with recent-onset RA. The current study was performed to evaluate possible associations between serum levels of secretory ACPA and signs of lung involvement in patients with early, untreated RA.
View Article and Find Full Text PDFObjectives: Rheumatoid arthritis (RA)-specific anti-citrullinated protein/peptide antibodies (ACPAs) might contribute to bone loss and arthralgia before the onset of joint inflammation. We aimed to dissect additional mechanisms by which ACPAs might contribute to development of joint pathology.
Methods: Fibroblast-like synoviocytes (FLS) were isolated from the synovial membrane of patients with RA.
An increased repertoire of potential osteoclast (OC) precursors could accelerate the development of bone-erosive OCs and the consequent bone damage in rheumatoid arthritis (RA). Immature dendritic cells (DCs) can develop into OCs, however, the mechanisms underlying this differentiation switch are poorly understood. We investigated whether protein citrullination and RA-specific anti-citrullinated protein Abs (ACPAs) could regulate human blood-derived DC-OC transdifferentiation.
View Article and Find Full Text PDFBest Pract Res Clin Rheumatol
February 2017
Antibody-positive (seropositive) rheumatoid arthritis (RA) is a complex multiphasic disease developing in genetically susceptible individuals following environmental challenges (such as smoking). RA-associated autoantibodies can develop several years before any clinical signs of joint inflammation, suggesting that triggering of this autoimmunity occurs outside the joints. Epidemiological, clinical, and molecular studies in seropositive individuals at risk for developing RA as well as in early untreated RA suggest a potential role for mucosal sites (especially lung mucosa) as RA-associated autoimmunity trigger sites.
View Article and Find Full Text PDFBackground: Antibodies against citrullinated proteins (ACPA) are common in patients with rheumatoid arthritis (RA). ACPA can appear before disease onset and target many self-antigens. Citrullinated fibrin/fibrinogen represents a classical ACPA target antigen, and mass spectrometry of RA synovial fluid reveals elevated citrullinated (cit) fibrinogen (Fib) peptides compared to non-RA controls.
View Article and Find Full Text PDFBackground: Airway abnormalities and lung tissue citrullination are found in both rheumatoid arthritis (RA) patients and individuals at-risk for disease development. This suggests the possibility that the lung could be a site of autoimmunity generation in RA, perhaps in response to microbiota changes. We therefore sought to test whether the RA lung microbiome contains distinct taxonomic features associated with local and/or systemic autoimmunity.
View Article and Find Full Text PDFThe complexity of endometrial receptivity at the molecular level needs to be explored in detail to improve the management of infertility. Here, differential expression of transcriptomes in receptive endometrial glands and stroma revealed Ectonucleotide Pyrophosphatase/Phosphodiesterase 3 (ENPP3) as a progesterone regulated factor and confirmed by various methods, both at mRNA and protein level. The involvement of ENPP3 in embryo attachment was tested in an in vitro model for human embryo implantation.
View Article and Find Full Text PDFRheumatoid arthritis (RA) is a chronic inflammatory syndrome with a strong autoimmune component. The autoantigens in RA are neither tissue nor organ-specific, but comprise a broad collection of post-translational modified proteins, such as citrullinated proteins. These modifications are likely to be triggered by innate stimuli.
View Article and Find Full Text PDFObjectives: Rheumatoid arthritis (RA)-specific anti-citrullinated protein/peptide antibodies (ACPAs) appear before disease onset and are associated with bone destruction. We aimed to dissect the role of ACPAs in osteoclast (OC) activation and to identify key cellular mediators in this process.
Methods: Polyclonal ACPA were isolated from the synovial fluid (SF) and peripheral blood of patients with RA.