Current classification criteria for rheumatoid arthritis (RA) encompass clinical and immunological items and are capable of correctly identifying the majority of symptomatic RA patients. The presence of positive rheumatoid factor (RF) and/or and anti-cyclic citrullinated protein/peptide antibodies (ACPA) gaining increasing importance according to their serological titer eases the recognition of RA, yet the debate is open on whether this scoring system ought to be optimized by hierarchizing ACPA or the combination of ACPA and RF over single positivity, prioritizing specificity over sensitivity. The risk of misdiagnosis and misclassification are often entangled, yet they are not the same. In fact, while ideal diagnosis requires 100% sensitivity and specificity, classification criteria are conceived to gather a homogeneous patient population, favoring specificity over sensitivity. Nevertheless, as they are frequently summoned to support the diagnostic process in clinical practice, issues arise on how comprehensive those should be and on how frequently they should be updated in light of novel acquisitions regarding measurable RA-related abnormalities. In this viewpoint two different views on the topic are confronted, discussing the performance of available criteria and the potentiality and pitfalls of their refinement according to novel data on ACPA and RF contribution and emergence of newly discovered specificities.

Introduction: Tumour-associated antigens (TAA) have been implicated in cell adhesion and cancer metastasis formation, but also in inflammatory processes, such as rheumatoid arthritis (RA). There has been little information about the possible associations of TAAs with RA-related clinical and laboratory parameters, with impaired vascular pathophysiology in RA, as well as about the effects of antirheumatic drugs on TAA production. Therefore, we determined the effects of one-year tofacitinib treatment on TAA levels, as well as correlations of TAA levels with various RA-associated and vascular parameters. Patients and methods: Altogether, 26 RA patients received 5 mg bid or 10 mg bid tofacitinib treatment for 12 months. Ultrasound-based functional vascular assessments, such as common carotid intima-media thickness (ccIMT), brachial artery flow-mediated vasodilation (FMD) and carotid-femoral pulse-wave velocity (cfPWV), were determined at various timepoints. Serum concentrations of TAAs, including carcinoembryonic antigen (CEA), CA15-3, CA19-9, CA125, CA72-4, human epididymis protein 4 (HE4) and tissue polypeptide antigen (TPA), as well as various cytokines (TNF-α, IL-6, IL-8, VEGF) and PECAM-1 were determined by flow cytometry using a bead-based multiplex assay (LEGENDplex). Results: As previously determined and published, one-year tofacitinib treatment effectively suppressed disease activity and inflammation. Serum CA15-3 and HE4 levels significantly decreased both after 6 and 12 months compared to baseline (p < 0.05). CA19-9 levels significantly increased both after 6 and 12 months, while CEA levels transiently increased after 6 months versus baseline (p < 0.05). CA125, CA72-4 and TPA levels did not change over time. In various regression analyses, TAA levels showed variable, significant, positive associations with the 28-joint disease activity score (DAS28), CRP, ESR, RF, IL-6, TNF-α, IL-8 and PECAM-1 (p < 0.05). In addition, TAAs variably correlated with ccIMT and cfPWV (p < 0.05). Moreover, one-year changes in TAA levels variably correlated with DAS28, RF and some cytokines (p < 0.05), as well as with changes in DAS28, HAQ, CRP, ESR, IL-6, VEGF and ccIMT from baseline to 12 months (p < 0.05). Conclusions: JAK inhibition might decrease the levels of some TAAs and increase those of others. TAA levels might be associated with RA-related and vascular biomarkers. These results suggest that TAAs might play a role in inflammatory processes and vascular pathology underlying RA.

Background and Objectives: Multiple myeloma (MM) remains an incurable plasma cell malignancy with heterogeneous clinical outcomes. Although current prognostic systems integrate biochemical and cytogenetic parameters, they do not fully capture disease complexity. Adipocytes within the bone marrow microenvironment secrete adipokines that regulate inflammation, metabolism, and immune interactions and may influence disease progression. This study aimed to assess circulating adipokines and related microenvironmental mediators as potential biomarkers of disease activity and treatment response in MM. Materials and Methods: In this case–control, cross-sectional study, the serum levels of eight adipokine-related molecules—adiponectin, leptin, resistin, chemerin, adipsin, thrombospondin-1 (TSP-1), paraoxonase-1 (PON-1), and myeloperoxidase (MPO)—were measured in 40 MM patients and 38 age- and sex-matched healthy controls. Enzyme-linked immunosorbent assays (ELISA) and bead-based multiplex immunoassays were used. Associations with prognostic markers (serum β₂-microglobulin (sB2M), LDH, albumin, hemoglobin, renal function) and treatment response were analyzed using correlation and non-parametric statistical methods. Results: Compared to the controls, MM patients exhibited significantly higher circulating levels of adiponectin, resistin, chemerin, adipsin, TSP-1, and MPO, while leptin was decreased. Among clinical correlations, chemerin and PON-1 correlated positively with sB2M, TSP-1 correlated with LDH, and MPO correlated with M-protein and albumin. Resistin was lower in patients with renal impairment and an advanced disease stage. Adiponectin and TSP-1 were significantly lower in progressive disease compared to complete remission, suggesting their potential association with treatment response. Conclusions: This study demonstrates that multiple adipokines are dysregulated in MM and exhibit distinct associations with disease burden, renal function, and therapeutic response. Novel associations identified for TSP-1, PON-1, and adipsin highlight previously unrecognized microenvironmental pathways in MM biology. Adipokine profiling may complement established prognostic markers and provide new insights into the tumour microenvironment in MM.

Anti-melanoma differentiation-associated gene 5 (anti-MDA5) antibodies are critical biomarkers in myositis, associated with distinct clinical features and prognosis. This study aimed to evaluate the proportion of anti-MDA5 positivity and compare the diagnostic performance of local immunoblotting (IB) with gold-standard immunoprecipitation (IP). We performed a retrospective analysis of 3272 physician-requested anti-MDA5 IB determinations over a five-year period (2019–2023). A subsequent exploratory pilot study of ten Hungarian patients with myositis was conducted to compare IB results with radiolabeled protein IP. Confirmatory in-house enzyme-linked immunosorbent assay (ELISA) was used to distinguish between 140 kDa bands (anti-MDA5 vs. anti-NXP2). Indirect immunofluorescence (IIF) on HEp-2 cells was also evaluated. In the retrospective cohort, 3.7% (n = 121) of samples were non-negative. Among 64 borderline patients, only one (1.6%) had a definitive diagnosis of dermatomyositis (DM). Conversely, the proportion of confirmed myositis cases was notably higher among patients with strong positive IB results. In our exploratory cross-sectional pilot study, complete concordance between the two assays was observed for negative and strong positive results. Discrepancies were noted in borderline and weak positivity ranges, where anti-MDA5 was not detected by IP; instead, alternative autoantibodies were identified. The three IP-confirmed MDA5 positive samples were all validated by ELISA. The characteristic IIF cytoplasmic staining was identifiable in 2 out of 10 cases (20%). In our cohort, borderline IB cases were frequently potential false positives, highlighting the need for careful clinical evaluation. Borderline and weak results require clinical correlation or confirmatory testing to avoid misdiagnosis.

Systemic sclerosis (SSc) is a severe autoimmune rheumatic disease with high mortality. Epigenetic factors, particularly micro-RNAs (miRNAs), may contribute to its pathogenesis by regulating gene expression. In this cross-sectional study, we assessed altered miRNA–mRNA regulatory networks in SSc and associated them with disease-related biological processes. We analyzed the miRNA profiles and differentially expressed genes (DEGs) of peripheral blood mononuclear cells (PBMCs) from 52 SSc patients (42 women and 10 men; mean age: 59.1 years) and 24 age- and gender-matched healthy controls. Total RNA was isolated and subjected to high-throughput next-generation sequencing for both miRNA and mRNA profiling. We identified 58 differentially expressed miRNAs (DEMs), 33 upregulated and 25 downregulated in SSc. In parallel, 6610 DEGs were detected (Mann–Whitney U-test, p < 0.05); 31 remained upregulated and nine downregulated after false discovery rate (FDR) correction. Integration of miRNA and mRNA data revealed 180 validated inverse miRNA–mRNA interactions. Notably, 22 of 31 upregulated DEGs corresponded to targets of downregulated miRNAs, indicating coordinated derepression. Functional enrichment analyses highlighted pathways related to extracellular matrix (ECM) remodeling, immune responses, fibrosis, and transcriptional regulation. Our findings suggest that altered miRNA expression contributes to widespread transcriptional dysregulation in SSc, promoting pro-fibrotic and immune-activated molecular pathways through coordinated miRNA–mRNA interactions.

Systemic sclerosis (SSc) is associated with increased bone fragility, yet early, compartment-specific alterations and their osteoimmunological correlates remain incompletely characterized. This study aimed to assess bone status in SSc using dual X-ray absorptiometry (DXA) complemented by peripheral quantitative computed tomography (pQCT), and to evaluate their associations with a targeted osteoimmunological biomarker panel and clinical risk scores. This prospective cross-sectional study included 40 women with SSc (disease duration ≤ 7 years from diagnosis) and 45 non-immune female controls, frequency-matched by age. Bone status was assessed by DXA (lumbar spine, femoral neck) and distal radius pQCT. Serum levels of routine bone and mineral metabolism markers, alongside a targeted panel of osteoimmunological mediators (OPG, OPN, PDGF-BB, ACP5, RANKL, TNF-α, IL-6, IL-1β, DKK-1) using multiplex immunoassay were measured. FRAX scores were calculated to contextualize clinical fracture risk. With broadly comparable DXA-defined bone status, pQCT revealed significantly lower trabecular volumetric bone mineral density (vBMD) in SSc, while total and cortical+subcortical vBMD were comparable. Routine biochemical markers showed substantial overlap between groups, whereas SSc patients exhibited a distinct osteoimmune profile with significantly elevated OPG, ACP5, RANKL, PDGF-BB, IL-6, IL-1β, DKK-1, and RANKL/OPG after FDR correction. Exploratory biomarker–bone associations did not remain significant after correction for multiple testing. In women with relatively early SSc, pQCT identified compartment-specific differences, particularly within the trabecular compartment, despite comparable DXA-defined bone status. A distinct osteoimmunological biomarker profile was also observed in SSc, providing complementary information on disease-related skeletal alterations, while specific biomarker–bone associations require further confirmation.