B-Cell Activation Biomarkers in Salivary Glands Are Related to Lymphomagenesis in Primary Sjögren's Disease: A Pilot Monocentric Exploratory Study.

Primary Sjögren's disease is primarily driven by B-cell activation and is associated with a high risk of developing non-Hodgkin's lymphoma (NHL). Over the last few decades, microRNA-155 (miR-155) has arisen as a key regulator of B-cells. Nevertheless, its role in primary Sjögren's disease remains elusive. Thus, the purpose of this study was (i) to explore miR-155, B-cell activating factor (BAFF)-receptor (BAFF-R), and Interleukin 6 receptor (IL-6R) expression in the labial salivary glands (LSG) of patients with primary Sjögren's disease, aiming to identify potential B-cell activation biomarkers related to NHL development. Twenty-four patients with primary Sjögren's disease, and with available tissue blocks from a LSG biopsy performed at diagnosis, were enrolled. Among them, five patients developed B-cell NHL during follow-up (7.3 ± 3.1 years). A comparison group of 20 individuals with sicca disease was included. Clinical and laboratory parameters were recorded and the LSG biopsies were evaluated to assess local inflammation in terms of miR-155/BAFF-R and IL-6R expression. Stratifying the primary Sjögren's disease cohort according to lymphomagenesis, miR-155 was upregulated in primary Sjögren's disease patients who experienced NHL, more so than those who did not experience NHL. Moreover, miR-155 expression correlated with the focus score (FS), as well as BAFF-R and IL-6R expression, which were increased in primary Sjögren's disease patients and in turn related to neoplastic evolution. In conclusion, epigenetic modulation may play a crucial role in the aberrant activation of B-cells in primary Sjögren's disease, profoundly impacting the risk of NHL development.

Intensive training programme for ultrasound-guided minimally invasive synovial tissue biopsy on knees and wrists in different phases of inflammation.

OBJECTIVES: To develop an intensive training programme for ultrasound (US)-guided synovial tissue (ST) biopsy on knees and wrists in inflammatory arthritis and to assess the learning curve, patient tolerability, sample quality and trainees' expectations. METHODS: Active or remission rheumatoid arthritis patients were enrolled. Nine trainees joined the 4-month programme in a centre experienced in performing US-guided ST biopsies consisting of four sequential phases: (1) observation, (2) performance of guided step-by-step phases, (3) execution of the whole procedure on paired joints (knees or wrists) of the same patient in parallel with the trainer and (4) performance of the procedure autonomously. Sample representativity was assessed by histology, and procedure-related adverse events were recorded. Before and after the programme, trainees' expectations and perceptions were collected. RESULTS: 328 ST biopsy procedures were included. The rate of trainees' informative samples was: (1) comparable to the trainers in active and remission knees, but lower in active wrists (70% for trainees vs 100% for trainers, p=0.06) in phase 3; (2) excellent on active knees and wrists (91.9% and 90.9% respectively) but lower (77.6%, p=0.0089) on remission knees in phase 4. Procedures performed by trainees did not affect patient tolerability. Trainees' expectations about procedure-related invasiveness and pain infliction decreased while the difficulty of procedure execution on active wrists and remission knees remained perceived as moderately difficult. CONCLUSIONS: This intensive training programme develops advanced skills in the performance of US-guided ST biopsy on knees and wrists, yielding high-quality specimens available for basic and translational studies on inflammatory joint diseases.

Bosentan Does Not Affect Renal Resistive Index in Scleroderma/Systemic Sclerosis Patients.

INTRODUCTION: If properly evaluated, chronic kidney disease can be found in up to 50% of patients with systemic sclerosis (SSc). The renal resistive index (RRI) is a marker of intrarenal vascular resistance and can predict SSc-associated vasculopathy. This study aimed to determine the impact of bosentan, a nonselective endothelin-1 receptor antagonist, on RRI and kidney function in SSc patients with recurrent digital ulcers. METHODS: Twenty-one patients (age 57 ± 9 years, 19 females) were recruited in a 16-week prospective open-label uncontrolled study. Standardized procedures were used to measure general clinical and laboratory characteristics, systolic, diastolic, and mean arterial pressure (MAP), pulse pressure (PP), diastolic to systolic blood pressure (D/S) ratio, and urinary endothelin-1 levels. The Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation was used to calculate kidney function as an estimated glomerular filtration rate (eGFR). RRI was measured by Doppler ultrasound as the average of three samplings of intrarenal blood flow in different kidney regions of both kidneys. Patients with secondary causes of kidney disease or kidney diseases associated with albuminuria were excluded. RESULTS: Bosentan treatment for 16 weeks did not change RRI (0.731 ± 0.049-0.730 ± 0.054, p = 0.925), but increased urine endothelin-1 to creatinine ratio (0.27 ± 0.15-0.49 ± 0.57 pg/mg, p = 0.032) and reduced MAP (123 ± 10-101 ± 11 mm Hg, p < 0.001), PP (76 ± 11-68 ± 10 mm Hg, p = 0.003), D/S ratio (0.563 ± 0.044-0.538 ± 0.031, p = 0.006), and eGFR (92 ± 20-84 ± 24 mL/min/1.73 m2, p = 0.003). DISCUSSION/CONCLUSION: In conclusion, in patients with SSc complicated by digital ulcers and normal to mildly diminished kidney function, bosentan had no effect on intrarenal hemodynamics, but reduced blood pressure levels and kidney function.

COVID-19 illness: Different comorbidities may require different immunological therapeutic targets.

BACKGROUND: The SARS-CoV-2 pandemic has led to more than 6,870.000 deaths worldwide. Despite recent therapeutic advances, deaths in Intensive Care Units still range between 34 and 72%, comprising substantial unmet need as we move to an endemic phase. The general agreement is that in the first few days of infection, antiviral drugs and neutralizing monoclonal antibodies should be adopted. When the patient is hospitalized and develops severe pneumonia, progressing to a systemic disease, immune modifying therapy with corticosteroids is indicated. Such interventions, however, are less effective in the context of comorbidities (e.g., diabetes, hypertension, heart failure, atrial fibrillation, obesity and central nervous system-CNS diseases) which are by themselves associated with poor outcomes. Such comorbidities comprise common and some distinct underlying inflammatory pathobiology regulated by differential cytokine taxonomy. METHODS: Searching in the PubMed database, literature pertaining to the biology underlying the different comorbidities, and the data from the studies related to various immunological treatments for the Covid-19 disease were carefully analyzed. RESULTS: Several experimental and clinical data have demonstrated that hypertension and atrial fibrillation present an IL-6 dependent signature, whereas diabetes, obesity, heart failure and CNS diseases may exhibit an IL-1a/b predominant signature. Distinct selective cytokine targeting may offer advantage in treating severe COVID-19 illness based on single or multiple associated comorbidities. When the patient does not immediately respond, a broader target range through JAKs pathway inhibitors may be indicated. CONCLUSIONS: Herein, we discuss the biological background associated with distinct comorbidities which might impact the SARS-CoV-2 infection course and how these should to be addressed to improve the current therapeutic outcome.

Effects of house dust mite subcutaneous immunotherapy in real-life. Immunological and clinical biomarkers and economic impact analysis.

Background: Etiology of allergic rhinitis and asthma is frequently associated with house dust mite sensitization and allergen immunotherapy (AIT) represents the only disease modifying treatment. In a real world setting, clinicians would benefit from biomarkers to monitor or predict response to AIT. Methods: Twenty-four consecutive house dust mite (HDM) mono-sensitized rhinitic patients, treated with subcutaneous immunotherapy (SCIT) as per clinical practice, were enrolled. Multiple in vitro biomarkers such as basophil activation (BAT), IL-10 levels, and molecular allergen-specific IgE were performed during HDM SCIT, to monitor the effects of AIT and then correlated to in vivo scores (VAS, CMSS, RQLQ). Nasal cytology was performed at baseline and after 6 and 12 months of treatment. Finally, the economic impact of SCIT in this cohort of patients was evaluated. Results: Clinical biomarkers confirmed to be useful to monitor AIT efficacy. As for laboratory biomarkers, BAT showed a reduction trend, particularly for D2C1, suggesting that this is a useful parameter in monitoring patients. IL-10 levels tend to remain stable or slightly decrease during treatment. The economic analysis confirmed the favorable impact of immunotherapy. Conclusions: In this cohort of patients, SCIT confirmed its effectiveness in reducing symptoms and drug utilization. Clinical scores confirmed to be valid in monitoring patients and their response. BAT demonstrated to be useful in monitoring more than predicting response. Further studies are needed to better explore the usefulness of these biomarkers in AIT.

The forgotten key players in rheumatoid arthritis: IL-8 and IL-17 - Unmet needs and therapeutic perspectives.

Despite the relevant advances in our understanding of the pathogenetic mechanisms regulating inflammation in rheumatoid arthritis (RA) and the development of effective therapeutics, to date, there is still a proportion of patients with RA who do not respond to treatment and end up progressing toward the development of joint damage, extra-articular complications, and disability. This is mainly due to the inter-individual heterogeneity of the molecular and cellular taxonomy of the synovial membrane, which represents the target tissue of RA inflammation. Tumor necrosis factor alpha (TNFα) and interleukin-6 (IL-6) are crucial key players in RA pathogenesis fueling the inflammatory cascade, as supported by experimental evidence derived from in vivo animal models and the effectiveness of biologic-Disease Modifying Anti-Rheumatic Drugs (b-DMARDs) in patients with RA. However, additional inflammatory soluble mediators such as IL-8 and IL-17 exert their pathogenetic actions promoting the detrimental activation of immune and stromal cells in RA synovial membrane, tendons, and extra-articular sites, as well as blood vessels and lungs, causing extra-articular complications, which might be excluded by the action of anti-TNFα and anti-IL6R targeted therapies. In this narrative review, we will discuss the role of IL-8 and IL-17 in promoting inflammation in multiple biological compartments (i.e., synovial membrane, blood vessels, and lung, respectively) in animal models of arthritis and patients with RA and how their selective targeting could improve the management of treatment resistance in patients.

Ecology and Machine Learning-Based Classification Models of Gut Microbiota and Inflammatory Markers May Evaluate the Effects of Probiotic Supplementation in Patients Recently Recovered from COVID-19.

Gut microbiota (GM) modulation can be investigated as possible solution to enhance recovery after COVID-19. An open-label, single-center, single-arm, pilot, interventional study was performed by enrolling twenty patients recently recovered from COVID-19 to investigate the role of a mixed probiotic, containing Lactobacilli, Bifidobacteria and Streptococcus thermophilus, on gastrointestinal symptoms, local and systemic inflammation, intestinal barrier integrity and GM profile. Gastrointestinal Symptom Rating Scale, cytokines, inflammatory, gut permeability, and integrity markers were evaluated before (T0) and after 8 weeks (T1) of probiotic supplementation. GM profiling was based on 16S-rRNA targeted-metagenomics and QIIME 2.0, LEfSe and PICRUSt computational algorithms. Multiple machine learning (ML) models were trained to classify GM at T0 and T1. A statistically significant reduction of IL-6 (p < 0.001), TNF-α (p < 0.001) and IL-12RA (p < 0.02), citrulline (p value < 0.001) was reported at T1. GM global distribution and microbial biomarkers strictly reflected probiotic composition, with a general increase in Bifidobacteria at T1. Twelve unique KEGG orthologs were associated only to T0, including tetracycline resistance cassettes. ML classified the GM at T1 with 100% score at phylum level. Bifidobacteriaceae and Bifidobacterium spp. inversely correlated to reduction of citrulline and inflammatory cytokines. Probiotic supplementation during post-COVID-19 may trigger anti-inflammatory effects though Bifidobacteria and related-metabolism enhancement.

Effects of l-Arginine Plus Vitamin C Supplementation on l-Arginine Metabolism in Adults with Long COVID: Secondary Analysis of a Randomized Clinical Trial.

Altered l-arginine metabolism has been described in patients with COVID-19 and has been associated with immune and vascular dysfunction. In the present investigation, we determined the serum concentrations of l-arginine, citrulline, ornithine, monomethyl-l-arginine (MMA), and symmetric and asymmetric dimethylarginine (SDMA, ADMA) in adults with long COVID at baseline and after 28-days of l-arginine plus vitamin C or placebo supplementation enrolled in a randomized clinical trial, compared with a group of adults without previous history of SARS-CoV-2-infection. l-arginine-derived markers of nitric oxide (NO) bioavailability (i.e., l-arginine/ADMA, l-arginine/citrulline+ornithine, and l-arginine/ornithine) were also assayed. Partial least squares discriminant analysis (PLS-DA) models were built to characterize systemic l-arginine metabolism and assess the effects of the supplementation. PLS-DA allowed discrimination of participants with long COVID from healthy controls with 80.2 ± 3.0% accuracy. Lower markers of NO bioavailability were found in participants with long COVID. After 28 days of l-arginine plus vitamin C supplementation, serum l-arginine concentrations and l-arginine/ADMA increased significantly compared with placebo. This supplement may therefore be proposed as a remedy to increase NO bioavailability in people with long COVID.

Effects of l-Arginine Plus Vitamin C Supplementation on Physical Performance, Endothelial Function, and Persistent Fatigue in Adults with Long COVID: A Single-Blind Randomized Controlled Trial.

Long COVID, a condition characterized by symptom and/or sign persistence following an acute COVID-19 episode, is associated with reduced physical performance and endothelial dysfunction. Supplementation of l-arginine may improve endothelial and muscle function by stimulating nitric oxide synthesis. A single-blind randomized, placebo-controlled trial was conducted in adults aged between 20 and 60 years with persistent fatigue attending a post-acute COVID-19 outpatient clinic. Participants were randomized 1:1 to receive twice-daily orally either a combination of 1.66 g l-arginine plus 500 mg liposomal vitamin C or a placebo for 28 days. The primary outcome was the distance walked on the 6 min walk test. Secondary outcomes were handgrip strength, flow-mediated dilation, and fatigue persistence. Fifty participants were randomized to receive either l-arginine plus vitamin C or a placebo. Forty-six participants (median (interquartile range) age 51 (14), 30 [65%] women), 23 per group, received the intervention to which they were allocated and completed the study. At 28 days, l-arginine plus vitamin C increased the 6 min walk distance (+30 (40.5) m; placebo: +0 (75) m, p = 0.001) and induced a greater improvement in handgrip strength (+3.4 (7.5) kg) compared with the placebo (+1 (6.6) kg, p = 0.03). The flow-mediated dilation was greater in the active group than in the placebo (14.3% (7.3) vs. 9.4% (5.8), p = 0.03). At 28 days, fatigue was reported by two participants in the active group (8.7%) and 21 in the placebo group (80.1%; p < 0.0001). l-arginine plus vitamin C supplementation improved walking performance, muscle strength, endothelial function, and fatigue in adults with long COVID. This supplement may, therefore, be considered to restore physical performance and relieve persistent symptoms in this patient population.

Seropositivity-Dependent Association between LINE-1 Methylation and Response to Methotrexate Therapy in Early Rheumatoid Arthritis Patients.

BACKGROUND: Methotrexate (MTX) is considered the first choice among disease-modifying anti-rheumatic drugs (DMARDs) for rheumatoid arthritis (RA) treatment. However, response to it varies as approximately 40% of the patients do not respond and would lose the most effective period of treatment time. Therefore, having a predictive biomarker before starting MTX treatment is of utmost importance. Methylation of long interspersed nucleotide element-1 (LINE-1) is generally considered a surrogate marker for global genomic methylation, which has been reported to associate with disease activity after MTX therapy. METHODS: We performed a prospective study on 273 naïve early RA (ERA) patients who were treated with MTX, followed up to 12 months, and classified according to their therapy response. The baseline LINE-1 methylation levels in peripheral blood mononuclear cells (PBMC) of cases were assessed by bisulfite pyrosequencing. RESULTS: Baseline LINE-1 methylation level per se turned out not to predict the response to the therapy, nor did age, sex, body mass index, or smoking status. However, if cases were stratified according to positivity to rheumatoid factor (RF) and anti-citrullinated protein antibody (ACPA) or seronegativity, we observed an opposite association between baseline LINE-1 methylation levels and optimal response to MTX therapy among responders. The best response to MTX therapy was associated with hypermethylated LINE-1 among double-positive ERA cases (p-value: 0.002) and with hypomethylated LINE-1 in seronegative ERA patients (p-value: 0.01). CONCLUSION: The LINE-1 methylation level in PBMCs of naïve ERA cases associates with the degree of response to MTX therapy in an opposite way depending on the presence of RF and ACPA antibodies. Our results suggest LINE-1 methylation level as a new epigenetic biomarker for predicting the degree of response to MTX in both double-positive and seronegative ERA patients.

Peripheral blood CD4posCD25posFoxP3pos cells and inflammatory cytokines as biomarkers of response in rheumatoid arthritis patients treated with CTLA4-Ig.

BACKGROUND: Prognostic biomarkers of treatment response to distinct biologic disease-modifying anti-rheumatic drugs (b-DMARDs) are still lacking within the management of rheumatoid arthritis (RA). METHODS: Thirty-four b-DMARDs naive RA patients, divided by disease duration into early (cohort 1) and long standing (cohort 2), received CTLA4-Ig. At study entry, and every 3 months for 1 year, each patient underwent peripheral blood (PB)-derived CD4pos cell subpopulation assessment by flow cytometry, STAT3 and STAT5 expression by RT-PCR and IL-6, IL-12p70, TGFß, and IL-10 serum levels by ELISA. The DAS and CDAI remission was assessed at 6 and 12 months. RESULTS: DAS- and CDAI-defined remission within 12 months was achieved by 16 (47.1%) and 8 (23.5%) RA patients, respectively. Considering the whole RA cohort, CTLA4-Ig induced a significant decrease of IL-6 serum levels from baseline to 6 and 12 months, as well as of PB CD4posCD25posFoxP3pos cells at 6 and 12 months, and of CD4posIL17pos cells after 12 months. PB CD4pos cells of RA patients showed higher STAT3 and STAT5 expression than healthy controls, which remained unchanged within 12 months of treatment. At study entry, RA patients achieving DAS remission had significantly lower IL-6 serum levels than RA patients not achieving this outcome. In particular, having baseline IL-6 serum levels ≤ 8.4 pg/ml, significantly identified naïve to b-DMARDs RA patients more likely to achieve DAS-remission under CTLA4-Ig at 6 months (66.7%) compared to RA patients with baseline IL-6 serum levels > 8.4 pg/ml [15.4%, OR (95%Cis) 11.00 (1.75-55.82)]. Moreover, having CD4posCD25posFoxP3pos cells rate ≥ 6.0% significantly identifies naïve to b-DMARDs early RA patients more likely to achieve DAS remission at 6 months (83.3%) compared to RA patients with baseline CD4posCD25posFoxP3pos cells < 6.0% [16.7%, OR (95% Cis) 25.00 (1.00-336.81)]. CONCLUSIONS: Baseline IL-6 serum levels and peripheral blood-derived CD4pos subpopulations are putative novel prognostic biomarkers of CTLA4-Ig response in RA patients.

Infectious agents breaking the immunological tolerance: The holy grail in rheumatoid arthritis reconsidered.

Multiple Sclerosis (MS) has been shown to be linked to Epstein Barr Virus (EBV) infection, a virus that infects B cells inside the CNS. The seminal study raises a key interest into the infectious origin of several other autoimmune inflammatory diseases.We will discuss here the infectious agents that have been studied over the years in Rheumatoid Arthritis (RA), a crippling arthritis that was treated a century ago with gold salts (anti mycobacterial agent), chloroquine (anti malarial agent), or sulphasalazine (an antibacterial-antiinflammatory agent). Several infectious agents have been taken into consideration, i.e. Streptococcus group A, Proteus, Mycobacterium tuberculosis-MTB, Parvovirus B19, Epstein Barr virus, Porphyromonas gingivalis-Pg, Aggregatibacter actinomycetescomitans, and finally Haemophilus-Glaesserella parasuis-Hps. Of these agents only three satisfy the Witebski's criteria as possible pathogenetic causes of an autoimmune disease, i.e. MTB, Pg, Hps. We will discuss here how the immune tolerance might be broken, which could be the neoantigen or autoantigen involved, how the infectious agent was studied as a trigger capable of inducing arthritis in animal models. The preventive measures that should be adopted to lessen the impact of the infections, to prevent the burden and the severity of the illness are described.

Pro Nerve Growth Factor and Its Receptor p75NTR Activate Inflammatory Responses in Synovial Fibroblasts: A Novel Targetable Mechanism in Arthritis.

We have recently provided new evidence for a role of p75NTR receptor and its preferential ligand proNGF in amplifying inflammatory responses in synovial mononuclear cells of chronic arthritis patients. In the present study, to better investigate how activation of the p75NTR/proNGF axis impacts synovial inflammation, we have studied the effects of proNGF on fibroblast-like synoviocytes (FLS), which play a central role in modulating local immune responses and in activating pro-inflammatory pathways. Using single cell RNA sequencing in synovial tissues from active and treatment-naïve rheumatoid arthritis (RA) patients, we demonstrated that p75NTR and sortilin, which form a high affinity receptor complex for proNGF, are highly expressed in PRG4pos lining and THY1posCOL1A1pos sublining fibroblast clusters in RA synovia but decreased in RA patients in sustained clinical remission. In ex vivo experiments we found that FLS from rheumatoid arthritis patients (RA-FLS) retained in vitro a markedly higher expression of p75NTR and sortilin than FLS from osteoarthritis patients (OA-FLS). Inflammatory stimuli further up-regulated p75NTR expression and induced endogenous production of proNGF in RA-FLS, leading to an autocrine activation of the proNGF/p75NTR pathway that results in an increased release of pro-inflammatory cytokines. Our data on the inhibition of p75NTR receptor, which reduced the release of IL-1ß, IL-6 and TNF-α, further confirmed the key role of p75NTR activation in regulating inflammatory cytokine production. In a set of ex vivo experiments, we used RA-FLS and cultured them in the presence of synovial fluids obtained from arthritis patients that, as we demonstrated, are characterized by a high concentration of proNGF. Our data show that the high levels of proNGF present in inflamed synovial fluids induced pro-inflammatory cytokine production by RA-FLS. The blocking of NGF binding to p75NTR using specific inhibitors led instead to the disruption of this pro-inflammatory loop, reducing activation of the p38 and JNK intracellular pathways and decreasing inflammatory cytokine production. Overall, our data demonstrate that an active proNGF/p75NTR axis promotes pro-inflammatory responses in synovial fibroblasts, thereby contributing to chronic synovial inflammation, and point to the possible use of p75NTR inhibitors as a novel therapeutic approach in chronic arthritis.

Haemophilus parasuis (Glaesserella parasuis) as a Potential Driver of Molecular Mimicry and Inflammation in Rheumatoid Arthritis.

Background: Haemophilus parasuis (Hps; now Glaesserella parasuis) is an infectious agent that causes severe arthritis in swines and shares sequence similarity with residues 261-273 of collagen type 2 (Coll261-273), a possible autoantigen in rheumatoid arthritis (RA). Objectives/methods: We tested the presence of Hps sequencing 16S ribosomal RNA in crevicular fluid, synovial fluids, and tissues in patients with arthritis (RA and other peripheral arthritides) and in healthy controls. Moreover, we examined the cross-recognition of Hps by Coll261-273-specific T cells in HLA-DRB1*04pos RA patients, by T-cell receptor (TCR) beta chain spectratyping and T-cell phenotyping. Results: Hps DNA was present in 57.4% of the tooth crevicular fluids of RA patients and in 31.6% of controls. Anti-Hps IgM and IgG titers were detectable and correlated with disease duration and the age of the patients. Peripheral blood mononuclear cells (PBMCs) were stimulated with Hps virulence-associated trimeric autotransporter peptide (VtaA10755-766), homologous to human Coll261-273 or co-cultured with live Hps. In both conditions, the expanded TCR repertoire overlapped with Coll261-273 and led to the production of IL-17. Discussion: We show that the DNA of an infectious agent (Hps), not previously described as pathogen in humans, is present in most patients with RA and that an Hps peptide is able to activate T cells specific for Coll261-273, likely inducing or maintaining a molecular mimicry mechanism. Conclusion: The cross-reactivity between VtaA10755-766 of a non-human infectious agent and human Coll261-273 suggests an involvement in the pathogenesis of RA. This mechanism appears emphasized in predisposed individuals, such as patients with shared epitope.

Depression and Endothelial Dysfunction in Psoriatic Arthritis: Is There Any Possible Relationship?

Background: Cardiovascular events (CVEs) are the first cause of death in patients with psoriatic arthritis (PsA). Depression is a recognized risk factor in cardiovascular events and is frequently associated with PsA. Flow-mediated dilatation (FMD) is a widely used method for assessing endothelial dysfunction, a parameter with strong prognostic implications for CVEs. The study aims to explore the relationship between FMD, depressive symptoms and serum cytokines in a cohort of patients with PsA. Patients and Methods: FMD was assessed in 50 consecutive PsA patients aged between 30 and 75 years without known cerebrovascular and coronary heart disease or diabetes. Depressive symptoms were reported using the related subscale of the Hospital Anxiety and Depression Scale (HDS). Disease features, activity indexes, and adjusted Framingham risk score (aFRS) were calculated. Serum level of IL-6, TNF-α, and IL-17A were also assessed. Results: In PsA patients (age 50.7 ± 10.2 years, male 42%, disease duration 5.9 ± 3.3 years, Disease Activity in PSoriatic Arthritis (DAPSA) score 14.0 ± 9.4) FMD inversely correlated with the severity of depressive symptoms according to HDS (ρ = -0.339, p = 0.016), age (ρ = -0.507, p = 0.001), aFRS (rs = -0.453, p < 0.001), duration of PsA (ρ = -0.507, p = 0.001), intensity of pain (ρ = -0.507, p = 0.001), and DAPSA (ρ = -0.507, p = 0.001). No statistically significant correlation was found between FMD or HDS and serum cytokines concentrations. HDS predicted FMD in a model adjusted for age, aFRS, PsA duration, and pain intensity (ß = -0.271, p = 0.008), with depressive symptoms contributing directly to 6.4% of the variance. Conclusions: Depressive symptoms correlate with endothelial dysfunction with an exposure-response pattern in our cohort of PsA patients.

COVID-19 and RA share an SPP1 myeloid pathway that drives PD-L1+ neutrophils and CD14+ monocytes.

We explored the potential link between chronic inflammatory arthritis and COVID-19 pathogenic and resolving macrophage pathways and their role in COVID-19 pathogenesis. We found that bronchoalveolar lavage fluid (BALF) macrophage clusters FCN1+ and FCN1+SPP1+ predominant in severe COVID-19 were transcriptionally related to synovial tissue macrophage (STM) clusters CD48hiS100A12+ and CD48+SPP1+ that drive rheumatoid arthritis (RA) synovitis. BALF macrophage cluster FABP4+ predominant in healthy lung was transcriptionally related to STM cluster TREM2+ that governs resolution of synovitis in RA remission. Plasma concentrations of SPP1 and S100A12 (key products of macrophage clusters shared with active RA) were high in severe COVID-19 and predicted the need for Intensive Care Unit transfer, and they remained high in the post-COVID-19 stage. High plasma levels of SPP1 were unique to severe COVID-19 when compared with other causes of severe pneumonia, and IHC localized SPP1+ macrophages in the alveoli of COVID-19 lung. Investigation into SPP1 mechanisms of action revealed that it drives proinflammatory activation of CD14+ monocytes and development of PD-L1+ neutrophils, both hallmarks of severe COVID-19. In summary, COVID-19 pneumonitis appears driven by similar pathogenic myeloid cell pathways as those in RA, and their mediators such as SPP1 might be an upstream activator of the aberrant innate response in severe COVID-19 and predictive of disease trajectory including post-COVID-19 pathology.

Loss of α2-6 sialylation promotes the transformation of synovial fibroblasts into a pro-inflammatory phenotype in arthritis.

In healthy joints, synovial fibroblasts (SFs) provide the microenvironment required to mediate homeostasis, but these cells adopt a pathological function in rheumatoid arthritis (RA). Carbohydrates (glycans) on cell surfaces are fundamental regulators of the interactions between stromal and immune cells, but little is known about the role of the SF glycome in joint inflammation. Here we study stromal guided pathophysiology by mapping SFs glycosylation pathways. Combining transcriptomic and glycomic analysis, we show that transformation of fibroblasts into pro-inflammatory cells is associated with glycan remodeling, a process that involves TNF-dependent inhibition of the glycosyltransferase ST6Gal1 and α2-6 sialylation. SF sialylation correlates with distinct functional subsets in murine experimental arthritis and remission stages in human RA. We propose that pro-inflammatory cytokines remodel the SF-glycome, converting the synovium into an under-sialylated and highly pro-inflammatory microenvironment. These results highlight the importance of glycosylation in stromal immunology and joint inflammation.

Inclusion of Synovial Tissue-Derived Characteristics in a Nomogram for the Prediction of Treatment Response in Treatment-Naive Rheumatoid Arthritis Patients.

OBJECTIVE: This study applied a synovitis score obtained during routine care from ultrasound (US)-guided biopsies of synovial tissue (ST) in patients with rheumatoid arthritis (RA) and patients with other inflammatory and noninflammatory joint diseases to identify pretreatment synovial biomarkers associated with disease characteristics, and to integrate the findings into a multiparameter nomogram for use in baseline prediction of diagnosis and treatment response in treatment-naive rheumatoid arthritis (RA) patients. METHODS: The study enrolled a total of 1,015 patients with various autoimmune diseases (545 patients with RA, 167 patients with psoriatic arthritis [PsA], 199 patients with undifferentiated peripheral inflammatory arthritis [UPIA], 18 patients with crystal-induced arthritis, 26 patients with connective tissue diseases, and 60 patients with osteoarthritis [OA] [as part of the SYNGem cohort]). All patients underwent a US-guided ST biopsy at baseline, and patients were then stratified according to disease phase. The KSS, along with disease characteristics and clinical outcomes, were incorporated into a nomogram for prediction of achievement of clinical remission in RA patients who were previously naive to treatment. In patients in whom a treat-to-target strategy was applied, remission was defined as change in the Disease Activity Score in 28 joints (DAS28) at 6 months after treatment initiation. RESULTS: The KSS significantly differed among RA patients, as well as PsA patients and UPIA patients, when compared to OA patients. In RA, the KSS directly correlated with the DAS28 and was related to autoantibody positivity in treatment-naive RA patients. Moreover, at baseline, treatment-naive RA patients achieving 6-month remission according to DAS28 had a lower KSS, shorter duration of symptoms (very early RA [VERA]), and lower disease activity than treatment-naive RA patients not achieving remission according to DAS28. Results of logistic regression analysis identified the following synergistic predictive factors of achievement of DAS28-based disease remission at 6 months: having a short disease duration (VERA), not having high disease activity, and having a KSS of <5 at baseline. A nomogram integrating these baseline clinical and histologic characteristics in treatment-naive RA patients yielded an up to 81.7% probability of achieving 6-month remission according to the DAS28. CONCLUSION: The KSS is a reliable tool for synovitis assessment on US-guided ST biopsy, contingent on the phase of the disease and the autoimmune profile of each patient. This tool could be integrated within a therapeutic response-predictive nomogram for the prediction of treatment response in RA patients who were previously naive to treatment.

Systemic Bone Density at Disease Onset Is Associated With Joint Erosion Progression in Early Naive to Treatment Rheumatoid Arthritis: A Prospective 12-Month Follow-Up Open-Label Study.

Objectives: Osteoporosis and bone erosions are hallmarks of rheumatoid arthritis (RA) since disease onset is underpinned by the inflammatory burden. In this observational study, we aimed to dissect the putative RA-related parameters and bone-derived biomarkers associated with systemic and focal bone loss at disease onset and with their progression. Methods: One-hundred twenty-eight patients with early rheumatoid arthritis (ERA) were recruited at disease onset. At study entry, demographic, clinical, and immunological parameters were recorded. Each ERA patient underwent plain X-rays of the hands and feet at study entry and after 12 months to assess the presence of erosions. After enrollment, each patient was treated according to the recommendations for RA management and followed up based on a treat-to-target (T2T) strategy. At baseline, blood samples for soluble biomarkers were collected from each patient, and plasma levels of osteoprotegerin (OPG), receptor activator of nuclear factor κB ligand (RANKL), Dickkopf-1 (DKK1), and interleukin 6 (IL-6) were assessed by enzyme-linked immunosorbent assay (ELISA). Seventy-one ERA patients underwent bone mineral density (BMD) measurement at the left femoral neck and second to fourth lumbar spine vertebrae (L2-L4) by dual-energy X-ray absorptiometry (DXA). Results: Among the whole cohort, 34 (26.6%) ERA patients with bone erosions at study entry had a higher disease activity (p = 0.02) and IL-6 plasma levels (p = 0.03) than non-erosive ones. Moreover, at DXA, 33 (46.5%) ERA patients had osteopenia, and 16 (22.5%) had osteoporosis; patients with baseline bone erosions were more likely osteopenic/osteoporotic than non-erosive ones (p = 0.03), regardless of OPG, RANKL, and DKK1 plasma levels. Obese ERA patients were less likely osteopenic/osteoporotic than normal weight ones (p = 0.002), whereas anti-citrullinated protein antibodies (ACPA) positive ERA patients were more likely osteopenic/osteoporotic than ACPA negative ones (p = 0.034). At logistic regression analysis, baseline Disease Activity Score measured on 44 joints (DAS44) [OR: 2.46 (1.11-5.44)] and osteopenic/osteoporosis status [OR: 7.13 (1.27-39.94)] arose as independent factors of erosiveness. Baseline osteopenic/osteoporotic status and ACPA positivity were associated with bone damage progression during the follow-up. Conclusions: Bone erosions presence is associated with systemic bone loss since the earliest phases of RA, suggesting that the inflammatory burden and autoimmune biology, underpinning RA, represent crucial enhancers of bone remodeling either locally as at systemic level.