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Search Results (158)

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Keywords = anti-citrullinated antibodies

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13 pages, 440 KiB  
Article
Demographic Characteristics and Inflammatory Biomarker Profile in Psoriatic Arthritis Patients with Comorbid Fibromyalgia: A Cross-Sectional Study
by Marino Paroli, Chiara Gioia, Daniele Accapezzato and Rosalba Caccavale
Medicina 2025, 61(6), 1050; https://doi.org/10.3390/medicina61061050 - 6 Jun 2025
Viewed by 595
Abstract
Background and Objectives: Psoriatic arthritis (PsA) is a chronic rheumatic disease that is frequently associated with fibromyalgia (FM). The coexistence of FM complicates the evaluation of PsA disease activity and the planning of treatment strategies, as the two conditions share many overlapping clinical [...] Read more.
Background and Objectives: Psoriatic arthritis (PsA) is a chronic rheumatic disease that is frequently associated with fibromyalgia (FM). The coexistence of FM complicates the evaluation of PsA disease activity and the planning of treatment strategies, as the two conditions share many overlapping clinical symptoms. To investigate the contribution of demographic factors and available serum biomarkers of inflammation and autoimmunity in characterizing the heterogeneity among patients meeting the classification criteria for both PsA and FM. Materials and Methods: This cross-sectional, single-center study involved 1547 adult patients evaluated between January 2017 and December 2024 who met the CASPAR criteria for PsA. A patient subgroup also met the 2016 ACR criteria for FM. Demographic data, serum inflammatory markers such as C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR), and autoimmunity markers including antinuclear antibodies (ANA), rheumatoid factor (RF), and anti-citrullinated protein antibodies (ACPA) were evaluated. Statistical analyses included chi-square tests, t-tests, Mann–Whitney U tests, and multivariate logistic regression to identify independent predictors associated with the coexistence of PsA and FM. Results: A total of 254 patients (16.42%) were diagnosed with concomitant FM. Compared to patients with PsA alone, those with concurrent PsA and FM showed significantly lower C-reactive protein (CRP) levels (0.39 ± 0.74 vs. 2.88 ± 12.31 mg/dL; p < 0.001) and a higher frequency of antinuclear antibody (ANA) positivity (13.57% vs. 5.78%; p < 0.001). No significant differences were observed in rheumatoid factor (RF) or anti-citrullinated protein antibody (ACPA) positivity between the groups. Multivariate logistic regression identified female sex, ANA positivity, CRP levels ≤ 0.5 mg/dL, and elevated body mass index (BMI) as independent predictors of the presence of concomitant FM. Conclusions: Patients with concomitant PsA and FM have a distinct demographic and serological profile, suggesting the existence of a clinically significant subgroup within the PsA population. Recognition of these differences may improve diagnostic accuracy and support the development of personalized, non-immunosuppressive therapeutic strategies for this subgroup of patients. Full article
(This article belongs to the Section Hematology and Immunology)
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11 pages, 731 KiB  
Article
Comparative Evaluation of Four Different Anti-CCP Assays for the Diagnosis of Rheumatoid Arthritis: A Diagnostic Performance Analysis
by Lydia Lamara Mahammed, Tamazouzt Hadjout, Asma Bensaci, Ryma Hamma, Ghalya Bousbia, Nawel Dahmani, Halima Ismail, Nadia Tamechmacht and Reda Djidjik
Diagnostics 2025, 15(10), 1293; https://doi.org/10.3390/diagnostics15101293 - 21 May 2025
Viewed by 1612
Abstract
Background/Objectives: Anti-cyclic citrullinated peptide (anti-CCP) antibodies are highly specific markers for rheumatoid arthritis (RA). Over the past decade, novel automating detection systems have been developed for anti-CCP detection. The present study aimed to evaluate the diagnostic performances of three fully automated anti-CCP [...] Read more.
Background/Objectives: Anti-cyclic citrullinated peptide (anti-CCP) antibodies are highly specific markers for rheumatoid arthritis (RA). Over the past decade, novel automating detection systems have been developed for anti-CCP detection. The present study aimed to evaluate the diagnostic performances of three fully automated anti-CCP assays in comparison to a conventional manual enzyme-linked immunosorbent assay (ELISA). Methods: One hundred ninety-nine patients with rheumatic symptoms (100 with RA and 99 without RA) were tested for anti-CCP autoantibodies using four assays: a manual-ELISA (EUROIMMUN®), two chemiluminescence immunoassays (CLIAs) performed on the MAGLUMI X3® and iFlash 1800® platforms, and an enzyme immunoassay (EIA) run on the UNI® analyzer. Results: The Kappa statistic indicated a moderate qualitative agreement among the EUROIMMUN, iFlash, and UNI assays (0.734 ≤ ĸ ≤ 0.778), while the MAGLUMI anti-CCP assay showed only weak-to-moderate agreement with the others (0.510 ≤ ĸ ≤ 0.628). A strong positive correlation was observed between anti-CCP levels measured by the four assays (0.747 ≤ rho ≤ 0.839). At the manufacturers’ cut-off values, sensitivities ranged from 76% to 99% and specificities from 69.7% to 99%, depending on the assay. However, at a fixed specificity of 95%, all the four assays showed good diagnostic performances for RA, with sensitivities ranging from 80% to 89% and positive likelihood ratios (LRs+) from 16 to 17.8. Conclusions: Our results revealed that at the manufacturers’ cut-offs, the UNI anti-CCP assay was the most valuable alternative to the conventional ELISA for diagnosing RA in our cohort. Nevertheless, after an appropriate adjustment of the thresholds, all the evaluated assays showed good diagnostic performances for RA. Full article
(This article belongs to the Section Clinical Laboratory Medicine)
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16 pages, 2136 KiB  
Systematic Review
Periodontal Pathogens Correlate with Rheumatoid Arthritis Disease Parameters: A Systematic Review Based on Clinical Studies
by Luki Astuti, Sri Lelyati Chaidar Masulili, Indrayadi Gunardi, Benso Sulijaya and Yuniarti Soeroso
Dent. J. 2025, 13(5), 214; https://doi.org/10.3390/dj13050214 - 15 May 2025
Viewed by 826
Abstract
Background: Numerous studies have found higher levels of autoantibodies including anti citrullinated protein antibodies (ACPAs), anti-cyclic citrullinated peptides (aCCP), or rheumatoid factor (RF) against periodontal microorganisms in rheumatoid arthritis (RA). Objective: To evaluate the correlation between periodontal bacteria and RA disease parameters. [...] Read more.
Background: Numerous studies have found higher levels of autoantibodies including anti citrullinated protein antibodies (ACPAs), anti-cyclic citrullinated peptides (aCCP), or rheumatoid factor (RF) against periodontal microorganisms in rheumatoid arthritis (RA). Objective: To evaluate the correlation between periodontal bacteria and RA disease parameters. Methods: We utilized PubMed, Scopus, ScienceDirect, and manual search databases up until March 2024 using PRISMA 2020 guidelines. The data were obtained from microbiological assays by RT-PCR/qPCR, sequencing, and serological testing of disease parameters (ACPA, aCCP, and RF) utilizing ELISA method. Results: A total of 1514 documents were discovered based on the inclusion criteria. Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans, and Prevotella_9 were associated with elevated levels of ACPA/aCCP and RF in RA with periodontitis. A positive correlation was found between Peptococcus simiae, Aminipila butyrica, Leptotrichia spp., Leptotrichia wadei, and Neisseria bacilliformis with ACPA, and Treponema sp. canine oral taxon 087 with RF. Conclusions: This study found that several oral microorganisms correlate with elevated ACPA/aCCP and RF in RA with periodontitis. Future studies of the oral microbiome and the molecular mechanisms are anticipated to discover new therapies and diagnostic methods for periodontitis and RA. Full article
(This article belongs to the Special Issue New Perspectives in Periodontology and Implant Dentistry)
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18 pages, 746 KiB  
Review
Animal Models in Rheumatoid Arthritis: Is There a Correlation Between Autoantibodies in Human Pathology and Animal Models?
by Miguel Marco-Bonilla, Maria Fresnadillo, Macarena de la Riva-Bueno, Gabriel Herrero-Beaumont, Raquel Largo and Aránzazu Mediero
Biology 2025, 14(5), 460; https://doi.org/10.3390/biology14050460 - 24 Apr 2025
Viewed by 1012
Abstract
RA is a chronic autoimmune disease characterized by synovial inflammation and joint damage, driven by autoantibodies such as ACPA, anti-CarP and RF. These autoantibodies, influenced by genetic and environmental factors, play a crucial role in RA pathogenesis through post-translational modifications like citrullination, carbamylation, [...] Read more.
RA is a chronic autoimmune disease characterized by synovial inflammation and joint damage, driven by autoantibodies such as ACPA, anti-CarP and RF. These autoantibodies, influenced by genetic and environmental factors, play a crucial role in RA pathogenesis through post-translational modifications like citrullination, carbamylation, and acetylation. The early detection of ACPA provides a potential window for intervention, while anti-CarP antibodies correlate with severe disease progression and RF aids in diagnosis. Translating these findings from human pathology to animal models presents significant challenges. Although the presence of adaptative immune cells (T cells) is well defined in animal models of RA, studies yield inconsistent results regarding autoantibody production and implication in the disease onset and progression, with varying detectability of ACPA, anti-CarP antibodies, and RF across different species and models. The collagen-induced arthritis (CIA) model shows PAD4 expression and citrullinated protein presence but inconsistent ACPA detection, while the K/BxN model elucidates the pathogenicity of anti-GPI autoantibodies and implicates Fcγ receptors in disease processes. Therefore, further research is needed to bridge the gap between animal models and human RA pathology. Future studies should focus on developing more representative animal models, exploring pharmacological targets and pathways that involve the interplay between anti-inflammatory and autoimmune responses, and investigating the complex interplay between genetic predisposition, environmental triggers, and autoimmune mechanisms. This approach may lead to improved early diagnostic tools, targeted therapies, and potentially preventive strategies for RA, ultimately enhancing patient outcomes and quality of life. Full article
(This article belongs to the Special Issue Animal Models of Arthritis)
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17 pages, 2551 KiB  
Article
Platelet-Derived Soluble CD40L and Its Impact on Immune Modulation and Anti-IL6R Antibody Treatment Outcome in Rheumatoid Arthritis
by Carlos Zamora, Cesar Diaz-Torne, Maria Angels Ortiz, Patricia Moya, Hye Sang Park, Concepció Pitarch, Elisabet Cantó, Ruben Osuna-Gomez, Maria Mulet, Maisa Garcia-Arguinzonis, Diego Collado, Hector Corominas and Silvia Vidal
Cells 2025, 14(9), 625; https://doi.org/10.3390/cells14090625 - 22 Apr 2025
Viewed by 765
Abstract
Background: Platelets (PLTs) from healthy donors (HD) modulate T lymphocyte responses but PLTs from rheumatoid arthritis (RA) patients contribute to persistent systemic inflammation. This suggests that PLTs from RA patients and HD have different immunomodulatory effects. Methods: Using cell culture, flow cytometry, proteomics, [...] Read more.
Background: Platelets (PLTs) from healthy donors (HD) modulate T lymphocyte responses but PLTs from rheumatoid arthritis (RA) patients contribute to persistent systemic inflammation. This suggests that PLTs from RA patients and HD have different immunomodulatory effects. Methods: Using cell culture, flow cytometry, proteomics, and ELISA, we compared PLTs from HD and RA patients and their effects on T lymphocyte activation and cytokine production. Results: HD PLTs suppressed T lymphocyte proliferation and IFNγ and TNF production, while RA PLTs exhibited reduced suppressive capacity. In the presence of RA PLTs, IFNγ levels correlated with T lymphocyte proliferation, greater disease activity, and anti-citrullinated protein antibodies (ACPA). Proteomic analysis revealed that RA PLTs show upregulation of proteins linked to acute-phase response and complement activation. RA PLTs secreted higher levels of soluble CD40L (sCD40L) and PDGF-BB that correlated with enhanced IFNγ production. Seropositive RA patients had higher levels of sCD40L, and these levels were predictive of disease remission in RA patients treated with anti-IL6R. sCD40L was found to enhance T lymphocyte activation and to contribute to increased pro-inflammatory cytokine production. Conclusions: This study highlights the diminished ability of RA PLTs to suppress T lymphocyte activation and that sCD40L can be a potential biomarker and therapeutic target in RA. Full article
(This article belongs to the Special Issue Molecular and Cellular Insights into Platelet Function)
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13 pages, 2771 KiB  
Case Report
Acquired Hemophilia Associated with Rheumatoid Arthritis: A Case Report and Review of the Literature
by Chiara Gioia, Marino Paroli, Valentina Morace, Lucrezia Nardacci, Sara Martina Ruffo, Elisabetta Rossi, Pasquale Pignatelli and Daniele Accapezzato
Int. J. Mol. Sci. 2025, 26(8), 3628; https://doi.org/10.3390/ijms26083628 - 11 Apr 2025
Viewed by 732
Abstract
A 63-year-old woman with rheumatoid arthritis and Hashimoto’s thyroiditis was admitted to the emergency room, because of left leg pain associated with spontaneous subcutaneous hematomas, for 15 days. Their symptoms also occurred after the discontinuation of aspirin, which the patient had taken for [...] Read more.
A 63-year-old woman with rheumatoid arthritis and Hashimoto’s thyroiditis was admitted to the emergency room, because of left leg pain associated with spontaneous subcutaneous hematomas, for 15 days. Their symptoms also occurred after the discontinuation of aspirin, which the patient had taken for a previous case of ocular papillitis. Laboratory tests showed anemia, a normal platelet count, but a prolonged activated partial thromboplastin time (aPTT) ratio; a computerized tomography scan of the left lower limb detected a recent hematoma in the left lateral rectus muscle, and subcutaneous soft tissue edema also involving the knee, without vascular involvement. Coagulation tests were performed showing normal levels of Lupus Anticoagulant, very low-factor FVIII activity (2.2%), normal FIX, FXI, and FXII activity, and the detection of FVIII inhibitors by a Bethesda assay (7.6 U). A diagnosis of acquired hemophilia A (AHA) was made, and hemostatic and immunosuppressive treatment was immediately started (activated prothrombin complex concentrates and methylprednisolone). Malignancies and infections were excluded. An autoantibodies panel confirmed the positivity to rheumatoid factor and anti-cyclic citrullinated peptide antibodies. In treatment, the patient did not present any new bruises, with aPTT normalizing, FVIII increasing, and inhibitors reducing until disappearance. A close follow-up continued every 1–2 week after discharge, with hemostatic treatment discontinuation and methylprednisolone decalage. Underlying autoimmune conditions induced this rare, autoimmune and life-threating disorder. Full article
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14 pages, 2223 KiB  
Article
Targeted Detection of 76 Carnitine Indicators Combined with a Machine Learning Algorithm Based on HPLC-MS/MS in the Diagnosis of Rheumatoid Arthritis
by Rui Zhang, Juan Wang, Xiaonan Zhai, Yuanbing Guo, Lei Zhou, Xiaoyan Hao, Liu Yang, Ruiqing Xing, Juanjuan Hu, Jiawei Gao, Fengjuan Wang, Jun Yang and Jiayun Liu
Metabolites 2025, 15(3), 205; https://doi.org/10.3390/metabo15030205 - 18 Mar 2025
Viewed by 650
Abstract
Background/Objectives: Early diagnosis and treatment of rheumatoid arthritis (RA) are essential to reducing disability. However, the diagnostic criteria remain unclear, relying on clinical symptoms and blood markers. Methods: Using high-performance liquid chromatography–mass spectrometry (HPLC-MS/MS) targeted detection, we evaluated 76 carnitine indicators (55 carnitines [...] Read more.
Background/Objectives: Early diagnosis and treatment of rheumatoid arthritis (RA) are essential to reducing disability. However, the diagnostic criteria remain unclear, relying on clinical symptoms and blood markers. Methods: Using high-performance liquid chromatography–mass spectrometry (HPLC-MS/MS) targeted detection, we evaluated 76 carnitine indicators (55 carnitines and 21 corresponding ratios) in the serum of patients with RA to investigate the role of carnitine in RA. A total of 359 patients (207 patients with RA and 152 healthy controls) were included in the study. Screening involved three methods and integrated 76 carnitine indicators and 128 clinical indicators to identify candidate markers to establish a theoretical basis for RA diagnosis and new therapeutic targets. The diagnostic model derived from the screened markers was validated using three machine learning algorithms. Results: The model was refined using eight candidate indicators (C0, C10:1, LYMPH, platelet distribution width, anti-keratin antibody, glucose, urobilinogen, and erythrocyte sedimentation rate (ESR)). The receiver operating characteristic curve, sensitivity, specificity, and accuracy of the V8 model obtained from the training set were >0.948, 79.46%, 92.99%, and 89.18%, whereas those of the test set were >0.925, 78.89%, 89.22%, and 85.87%, respectively. Twenty-four carnitines were identified as risk factors of RA, with three significantly correlating with ESR, four with anti-cyclic citrullinated peptide antibody activity, two with C-reactive protein, five with immunoglobulin-G, eight with immunoglobulin-A levels, and eleven with immunoglobulin-M levels. Conclusions: Carnitine is integral in the progression of RA. The diagnostic model developed shows excellent diagnostic capacity, improving early detection and enabling timely intervention to minimize disability associated with RA. Full article
(This article belongs to the Section Endocrinology and Clinical Metabolic Research)
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12 pages, 1301 KiB  
Article
Clinical Significance of Antinuclear Antibodies in Patients with Rheumatoid Arthritis: From SETOUCHI-RA Registry
by Kazuhisa Nakano, Shunichi Fujita, Sumie Hiramatsu-Asano, Akiko Nagasu, Shoko Tsuji, Yuka Koide, Masatomo Yamada, Yo Mizuta, Masakatsu Ikeda, Hiroyasu Hirano and Yoshitaka Morita
J. Clin. Med. 2025, 14(5), 1553; https://doi.org/10.3390/jcm14051553 - 26 Feb 2025
Viewed by 1469
Abstract
Background/Objectives: Rheumatoid arthritis (RA) is a representative systemic autoimmune rheumatic disease (SARD) characterized by synovial inflammation. While antinuclear antibodies (ANAs) positivity in patients with RA varies widely, the relationship between ANA patterns and clinical features remains unclear. This study aimed to evaluate the [...] Read more.
Background/Objectives: Rheumatoid arthritis (RA) is a representative systemic autoimmune rheumatic disease (SARD) characterized by synovial inflammation. While antinuclear antibodies (ANAs) positivity in patients with RA varies widely, the relationship between ANA patterns and clinical features remains unclear. This study aimed to evaluate the clinical significance of ANA in patients with RA. Methods: This single-center RA registry study included 814 Japanese patients after excluding those with coexisting SARDs. ANA titers and staining patterns were assessed by indirect immunofluorescence assays on HEp-2 cells. Clinical and laboratory features were analyzed, and logistic regression was used to identify risk factors for pulmonary involvement. Hierarchical clustering and statistical analyses were performed to explore associations between ANA patterns and clinical features. Results: ANA positivity was observed in 41.5% of patients, with the speckled and homogeneous patterns being the most common. ANA-positive patients exhibited significantly higher rheumatoid factor (RF) and anti-cyclic citrullinated peptide antibody (ACPA) positivity rates and titers, along with elevated disease activity markers, including Evaluator’s Global Assessment and Swollen Joint Count. Nucleolar pattern positivity was independently associated with pulmonary complications, predominantly interstitial lung disease, and higher rates of JAK inhibitor use. Discrete-speckled pattern-positive patients exhibited high ANA titers but lower RF and ACPA levels, reflecting a distinct subset of RA. Conclusions: ANA staining patterns and titers are clinically relevant in RA, with nucleolar and discrete-speckled patterns indicating distinct clinical and pathophysiological profiles. ANA should be interpreted alongside other serological markers and clinical parameters rather than as a standalone tool. Further studies are needed to refine its clinical applicability and integration into RA management. Full article
(This article belongs to the Special Issue Rheumatoid Arthritis: Clinical Updates on Diagnosis and Treatment)
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17 pages, 5705 KiB  
Article
A Multifaceted Computational Approach to Identify PAD4 Inhibitors for the Treatment of Rheumatoid Arthritis (RA)
by Mansour S. Alturki, Mohamed S. Gomaa, Nada Tawfeeq, Abdulaziz H. Al Khzem, Mohsina B. Shaik, Murtadha Alshaikh Jafar, Mohammad Alsamen, Hasan Al Nahab, Mohammad Al-Eid, Alhassan Almutawah, Thankhoe A. Rants’o, Khaled A. G. Ayil and Mohammed Almaghrabi
Metabolites 2025, 15(3), 156; https://doi.org/10.3390/metabo15030156 - 25 Feb 2025
Cited by 1 | Viewed by 1315
Abstract
Background/Objectives: Neutrophil cells’ lysis forms the extracellular traps (NETs) to counter the foreign body during insults to the body. Peptidyl arginine deiminase (PAD) participates in this process and is then released into the extracellular fluid with the lysed cell components. In some diseases, [...] Read more.
Background/Objectives: Neutrophil cells’ lysis forms the extracellular traps (NETs) to counter the foreign body during insults to the body. Peptidyl arginine deiminase (PAD) participates in this process and is then released into the extracellular fluid with the lysed cell components. In some diseases, patients with abnormal function of PADs, especially PAD 4, tend to form autoantibodies against the abnormal citrullinated proteins that are the result of PAD activity on arginine side chains. Those antibodies, which are highly distinct in RA, are distinctly anti-citrullinated protein antibodies (ACPA). This study used an in-silico drug repurposing approach of FDA-approved medications to identify potential alternative medications that can inhibit this process and address solutions to the current limitations of existing therapies. Methods: We utilized Maestro Schrödinger as a computational tool for preparing and docking simulations on the PAD 4 enzyme crystal structure that is retrieved from RCSB Protein Data Bank (PDB ID: 4X8G) while the docked FDA-approved medications are obtained from the Zinc 15 database. The protein was bound to GSK 199—an investigational compound—as a positive control for the docked molecules. Preparation of the protein was performed by Schrödinger Protein Preparation Wizard tool. Binding pocket determination was performed by Glide software (Schrödinger Release 2021–3:Schrödinger, LLC., New York, NY, USA, 2021). and validation of molecular docking was carried out through the redocking of GSK 199 and superimposition. After that, standard and induced fit docking were performed. Results/Conclusions: Among the four obtained hits Pemetrexed, Leucovorin, Chlordiazepoxide, and Ioversol, which showed the highest XP scores providing favorable binding interactions. The induced-fit docking (IFD) results displayed the strong binding affinities of Ioversol, Pemetrexed, Leucovorin, Chlordiazepoxide in the order IFD values −11.617, −10.599, −10.521, −9.988, respectively. This research investigates Pemetrexed, Leucovorin, Chlordiazepoxide, and Ioversol as potential repurposing agents in the treatment of rheumatoid arthritis (RA) as they are identified as PAD4 inhibitors. Full article
(This article belongs to the Section Advances in Metabolomics)
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20 pages, 3280 KiB  
Review
Rheumatoid Factor: Diagnostic and Prognostic Performance and Therapeutic Implications in Rheumatoid Arthritis
by Tasuku Togashi, Ryuhei Ishihara, Ryu Watanabe, Mayu Shiomi, Yuya Yano, Yuhei Fujisawa, Masao Katsushima, Kazuo Fukumoto, Shinsuke Yamada and Motomu Hashimoto
J. Clin. Med. 2025, 14(5), 1529; https://doi.org/10.3390/jcm14051529 - 25 Feb 2025
Cited by 3 | Viewed by 3478
Abstract
Rheumatoid factor (RF) is the first autoantibody identified in rheumatoid arthritis (RA) which targets the fragment crystallizable (Fc) region of immunoglobulin (Ig) G. Although IgM isotype is predominant, other Ig isotypes, including IgG and IgA, also exist. While RF is not specific to [...] Read more.
Rheumatoid factor (RF) is the first autoantibody identified in rheumatoid arthritis (RA) which targets the fragment crystallizable (Fc) region of immunoglobulin (Ig) G. Although IgM isotype is predominant, other Ig isotypes, including IgG and IgA, also exist. While RF is not specific to RA, it remains a valuable serological test for diagnosing the disease, as evidenced by its inclusion in the 2010 classification criteria for RA based on elevated serum RF levels. RF is also associated with RA severity, including joint damage and extra-articular manifestations, serving as a poor prognostic factor and aiding in the identification of difficult-to-treat RA. Recent studies have demonstrated that high serum RF levels are associated with a reduced response to tumor necrosis factor (TNF) inhibitors. In contrast, anti-TNF antibodies lacking the Fc portion have shown stable efficacy in RA patients regardless of baseline RF levels. These findings reaffirm the clinical significance of RF measurement, 80 years after its initial discovery. This review explores the diagnostic and prognostic significance of RF and its impact on treatment selection in RA management. Full article
(This article belongs to the Special Issue Rheumatoid Arthritis: Clinical Updates on Diagnosis and Treatment)
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28 pages, 5117 KiB  
Article
Exploring Anticitrullinated Antibodies (ACPAs) and Serum-Derived Exosomes Cargoes
by Mohammed A. Alghamdi, Sami M. Bahlas, Sultan Abdulmughni Alamry, Ehab H. Mattar and Elrashdy M. Redwan
Antibodies 2025, 14(1), 10; https://doi.org/10.3390/antib14010010 - 26 Jan 2025
Cited by 1 | Viewed by 1476
Abstract
Background: Autoantibodies such as rheumatoid factor (RF) and anticitrullinated protein autoantibodies (ACPAs) are useful tools for rheumatoid arthritis (RA). The presence of ACPAs against citrullinated proteins (CPs), especially citrullinated fibrinogen (cFBG), seems to be a useful serological marker for diagnosing RA. RA patients’ [...] Read more.
Background: Autoantibodies such as rheumatoid factor (RF) and anticitrullinated protein autoantibodies (ACPAs) are useful tools for rheumatoid arthritis (RA). The presence of ACPAs against citrullinated proteins (CPs), especially citrullinated fibrinogen (cFBG), seems to be a useful serological marker for diagnosing RA. RA patients’ sera were found to be enriched in exosomes that can transmit many proteins. Exosomes have been found to express citrullinated protein such as cFBG. Objective: We conducted this study in two stages. In the first phase, we aimed to evaluate the association between autoantibodies and risk factors. In the next step, ACPA-positive serum samples from the first phase were subjected to exosomal studies to explore the presence of cFBG, which is a frequent target for ACPAs. Methods: We investigated the autoantibodies in one hundred and sixteen Saudi RA patients and correlated with host-related risk factors. Exosomes were extracted from patients’ sera and examined for the presence of cFBG using monoclonal antibodies. Results: The study reported a high female-to-male ratio of 8:1, and seropositive RA (SPRA) was more frequent among included RA patients. The frequency and the levels of ACPAs were similar in both genders. Autoantibodies incidences have a direct correlations with patient age, while the average titers decreased as the age increased. Further, the highest incidence and levels of autoantibodies were reported in patients with RA duration between 5 and 10 years. Smoking and family history have no impact on autoantibody, except for ACPAs titers among smokers’ RA. Our analysis of serum exosomes revealed that about 50% of SPRA patients expressed cFBG. Conclusions: The female-to-male ratio is 8:1, which is higher than the global ratio. We can conclude that patients’ age and disease duration contribute to the autoantibodies, particularly RF and anti-MCV, whereas smoking and family history had no effects on autoantibodies. We detected cFBG in all exosomes from SPRA patients; thus, we suggest that the precise mechanism of exosomes in RA pathogenesis can be investigated to develop effective treatment strategies. Full article
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11 pages, 768 KiB  
Article
Impact of Likelihood Ratios of Rheumatoid Factor and Anti-Cyclic Citrullinated Peptide Antibody in Clinical Diagnosis of Rheumatoid Arthritis by Two Available Platforms
by Juan Irure-Ventura, María Díaz-Toledo, Noelia Palazuelos-Cayón and Marcos López-Hoyos
Diagnostics 2025, 15(2), 135; https://doi.org/10.3390/diagnostics15020135 - 8 Jan 2025
Cited by 1 | Viewed by 1129
Abstract
Background/Objectives: Rheumatoid arthritis (RA) is one of the most prevalent autoimmune diseases, characterized by an articular and extra-articular involvement, where autoantibodies, such as rheumatoid factor (RF) and anti-cyclic citrullinated peptide antibodies (ACPAs), are important biomarkers for the diagnosis. Autoantibody determination can be [...] Read more.
Background/Objectives: Rheumatoid arthritis (RA) is one of the most prevalent autoimmune diseases, characterized by an articular and extra-articular involvement, where autoantibodies, such as rheumatoid factor (RF) and anti-cyclic citrullinated peptide antibodies (ACPAs), are important biomarkers for the diagnosis. Autoantibody determination can be carried out using different assays. However, the results obtained are usually expressed in arbitrary units that are not comparable. Therefore, the aim of this study is to improve clinical interpretation of RF and ACPA test results using the likelihood ratio (LR). Methods: RF and ACPA titers were analyzed by turbidimetry and chemiluminescence using Optilite and BIO-FLASH systems, respectively, in 781 samples from patients with RA and in 1970 controls. Results: The higher the antibody titer of RF or ACPA, the higher the LR for RA. The definition of test result interval-specific LR based on predefined specificities for antibody levels provides more information than the use of the cut-off set by the manufacturer for each antibody. Conclusions: The LR for RA increased with an increasing antibody level. In addition, the use of test result interval-specific LR allows better clinical interpretation for RF and ACPA assays compared to the traditional idea of interpreting antibody results in a dichotomous manner, such as negative or positive. Full article
(This article belongs to the Special Issue Immune-Mediated Diseases: Diagnosis and Management)
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13 pages, 2004 KiB  
Article
Neutropenia and Felty Syndrome in the Twenty-First Century: Redefining Ancient Concepts in Rheumatoid Arthritis Patients
by Jorge Luis Rodas Flores, Blanca Hernández-Cruz, Víctor Sánchez-Margalet, Ana Fernández-Reboul Fernández, Esther Fernández Panadero, Gracia Moral García and José Javier Pérez Venegas
J. Clin. Med. 2024, 13(24), 7677; https://doi.org/10.3390/jcm13247677 - 17 Dec 2024
Viewed by 1910
Abstract
Objectives: To describe the frequency of neutropenia and Felty syndrome in patients with rheumatoid arthritis (RA) attended in routine clinical practice. Methods: We selected by randomization a sample of 270 RA patients attended from January 2014 to November 2022. Demographic, clinical, and neutropenia-related [...] Read more.
Objectives: To describe the frequency of neutropenia and Felty syndrome in patients with rheumatoid arthritis (RA) attended in routine clinical practice. Methods: We selected by randomization a sample of 270 RA patients attended from January 2014 to November 2022. Demographic, clinical, and neutropenia-related variables were collected from the electronic medical records. Neutropenia was defined as having an absolute neutrophil count (ANC) of less than 1500/mm3 once, and acute if it persisted for <3 months. Felty syndrome was defined as RA-related neutropenia, rheumatoid factor (RF) and/or anti citrullinated protein antibody (ACPA) positivity. Results: We found 50 patients who had at least one neutropenia episode, with an incidence of 18.5% (14.0–25.6%). Most were women, with age (mean, p25–p75) at the time of neutropenia of 61.5 (57.4–69.3) years, 85% RF+ and 76% ACPA+. The demographic and RA characteristics of patients with and without neutropenia were very similar, except for sex: most patients with neutropenia were women. The 50 patients had 99 episodes of neutropenia; 59% were acute. The lower ANC was 1240 (1000–1395) mm3, and most of the episodes were mild (74%). In 32% of cases, there was other cytopenia. The RA activity measured by DAS28 in patients with neutropenia was low, at 2.18 (1.75–2.97). A total of 82 of 99 neutropenia episodes were related to DMARDs, 60% to Anti-IL6 drugs in monotherapy, 13% to RA activity, 3% to infectious diseases and 1% to hematologic malignancy. There were five (1.8%) cases with Felty syndrome, but only one woman with the classic combination of RA, positivity of autoantibodies (RF and ACPA), neutropenia and splenomegaly. Conclusions: In the 21st century, neutropenia in RA patients is most commonly related to biologics, mostly IL6 inhibitors and methotrexate. Episodes are mild, acute, with low RA activity, and associated with severe infections in few cases. Felty syndrome is rare. Full article
(This article belongs to the Special Issue Rheumatoid Arthritis: Current Status and Future Challenges)
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16 pages, 1731 KiB  
Review
Unmet Needs and Current Challenges of Rheumatoid Arthritis: Difficult-to-Treat Rheumatoid Arthritis and Late-Onset Rheumatoid Arthritis
by Satoshi Takanashi and Yuko Kaneko
J. Clin. Med. 2024, 13(24), 7594; https://doi.org/10.3390/jcm13247594 - 13 Dec 2024
Cited by 3 | Viewed by 3462
Abstract
Despite remarkable advances in the management of RA, there are still unmet needs that rheumatologists need to address. In this review, we focused on difficult-to-treat RA (D2T RA) and late-onset RA (LORA), and summarized their characteristics and management. The prevalence of D2T RA [...] Read more.
Despite remarkable advances in the management of RA, there are still unmet needs that rheumatologists need to address. In this review, we focused on difficult-to-treat RA (D2T RA) and late-onset RA (LORA), and summarized their characteristics and management. The prevalence of D2T RA is reported to be 6–28% and many factors have been identified as risk factors for D2T RA, including female sex, long disease duration, seropositivity for rheumatoid factor and anti-cyclic citrullinated peptide antibody and their high titer, baseline high disease activity, and comorbidities. D2T RA is broadly divided into inflammatory and non-inflammatory conditions, and clinical features differ according to background. A proportion of D2T RA can be managed with treatment modification, mainly with interleukin-6 receptor inhibitors or Janus kinase inhibitors, but some D2T RA patients have a poor prognosis; thus, the implementation of precision medicine by stratifying patients according to disease status is needed. In the aging society, the epidemiology of RA is changing and the prevalence of LORA is increasing worldwide. LORA has distinct clinical features compared with young-onset RA, such as acute onset, low seropositivity, and high inflammation. The pathogenesis of LORA remains to be elucidated, but proinflammatory cytokines, including interleukin-6, have been reported to be significantly elevated. LORA has several management concerns other than RA itself, such as geriatric syndrome and multimorbidity. The treat-to-target strategy is effective for LORA, but the evidence is still lacking; thus, it is important to accumulate clinical and related basic data to establish the optimal treatment strategy for LORA. Full article
(This article belongs to the Special Issue Rheumatoid Arthritis: Clinical Updates on Diagnosis and Treatment)
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10 pages, 1148 KiB  
Article
Effectiveness and Predictors of Long-Term Treatment Response to Tofacitinib in Rheumatoid Arthritis Cohort: General Analysis and Focus on High-Cardiovascular-Risk Subgroup—A Multicenter Study
by Marta Priora, Andrea Becciolini, Eleonora Celletti, Myriam Di Penta, Alberto Lo Gullo, Marino Paroli, Elena Bravi, Romina Andracco, Valeria Nucera, Francesca Ometto, Federica Lumetti, Antonella Farina, Patrizia Del Medico, Matteo Colina, Viviana Ravagnani, Palma Scolieri, Maddalena Larosa, Elisa Visalli, Olga Addimanda, Rosetta Vitetta, Alessandro Volpe, Alessandra Bezzi, Francesco Girelli, Aldo Biagio Molica Colella, Rosalba Caccavale, Eleonora Di Donato, Giuditta Adorni, Daniele Santilli, Gianluca Lucchini, Eugenio Arrigoni, Emanuela Sabatini, Ilaria Platè, Natalia Mansueto, Aurora Ianniello, Enrico Fusaro, Maria Chiara Ditto, Vincenzo Bruzzese, Dario Camellino, Gerolamo Bianchi, Francesca Serale, Rosario Foti, Giorgio Amato, Francesco De Lucia, Ylenia Dal Bosco, Roberta Foti, Massimo Reta, Alessia Fiorenza, Guido Rovera, Antonio Marchetta, Maria Cristina Focherini, Fabio Mascella, Simone Bernardi, Gilda Sandri, Dilia Giuggioli, Carlo Salvarani, Veronica Franchina, Francesco Molica Colella, Giulio Ferrero, Alarico Ariani and Simone Parisiadd Show full author list remove Hide full author list
Medicina 2024, 60(12), 1982; https://doi.org/10.3390/medicina60121982 - 2 Dec 2024
Viewed by 1782
Abstract
Background and Objectives: The treatment landscape for Rheumatoid Arthritis (RA) has evolved significantly with the introduction of Janus kinase inhibitors (JAKi), such as Tofacitinib (TOFA), which offer a new therapeutic option for patients who have failed or are intolerant to conventional synthetic disease-modifying [...] Read more.
Background and Objectives: The treatment landscape for Rheumatoid Arthritis (RA) has evolved significantly with the introduction of Janus kinase inhibitors (JAKi), such as Tofacitinib (TOFA), which offer a new therapeutic option for patients who have failed or are intolerant to conventional synthetic disease-modifying antirheumatic drugs (csDMARDs). Safety concerns, particularly related to cardiovascular and cancer risks, prompted a need for additional investigation in real-world clinical settings. This study aimed to evaluate the long-term effectiveness and predictors of response to TOFA in two subpopulations of RA patients, categorized by differing cardiovascular risk profiles. Materials and Methods: This was a retrospective, multicenter observational study conducted as part of the BIRRA project, involving 23 Italian rheumatological referral centers. A total of 213 patients diagnosed with RA and treated with TOFA were included, with data collected on baseline demographics, clinical history, disease activity, and comorbidities. Patients were divided into high-risk and low-risk cardiovascular groups based on age (≥65 years) and the presence of at least one cardiovascular risk factor. Disease activity was assessed at baseline, 6 months, and 12 months using DAS28-ESR and DAS28-CRP. Treatment response was evaluated using intention-to-treat (ITT) and per-protocol (PP) approaches. Predictors of low disease activity (LDA) and remission were assessed through logistic regression, and clustering analyses were used to identify subgroups of patients with different therapeutic responses. Results: The study included 213 patients, with 129 classified as high-risk. For the overall cohort, patients achieving LDA and remission at 6 months were 20% and 12%, respectively, for the ITT analysis, and 29% and 14% for the PP analysis. At 12 months, 26% of patients reached LDA, and 17% achieved remission according to ITT, while for the PP analysis, these rates were 30% and 19%, respectively. No significant differences in remission or LDA rates were observed between the high-risk and low-risk groups. In the high-risk subgroup, 17% of patients reached LDA and 9% achieved remission at 6 months (ITT analysis), while these rates increased to 22% and 13%, respectively, in the PP analysis. At 12 months, 22% achieved LDA and 13% achieved remission in the ITT analysis, while 28% and 17% did so in the PP analysis. The reduction in DAS28-ESR and DAS28-CRP scores was significant (p < 0.001) across all time points for both high-risk and low-risk patients. Logistic regression analyses revealed that none of the baseline characteristics—including age, sex, comorbidities, rheumatoid factor, anti-citrullinated protein antibody (ACPA) positivity, initial disease severity, or treatment history—were significant predictors of remission or LDA at 6 or 12 months. The clustering analysis suggested that older patients, particularly those with worse baseline DAS28 scores, tended to show a less favorable response to treatment, potentially indicating impacts of age-related factors such as immunosenescence on therapeutic outcomes. Conclusions: Tofacitinib demonstrated similar effectiveness in both high- and low-risk cardiovascular subgroups of RA patients, with significant reductions in disease activity observed at both 6 and 12 months. Despite safety concerns related to cardiovascular risk, TOFA remained an effective treatment option across patient subgroups, with no significant differences in remission or LDA rates based on cardiovascular risk profiles. Age appeared to negatively impact treatment response, highlighting the role of immunosenescence in RA management. These findings support the use of TOFA as a personalized therapeutic option for RA, emphasizing the need for careful evaluation of cardiovascular and age-related risks in clinical decision-making. Full article
(This article belongs to the Special Issue Recent Advances in Autoimmune Rheumatic Diseases: 2nd Edition)
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