Identification and evolution of predictors of Sjögren's disease-associated mucosa-associated lymphoid tissue lymphoma development over time: a case-control study.

BACKGROUND: Non-Hodgkin lymphomas have a substantial impact on individuals with Sjögren's disease. This study focuses on mucosal-associated lymphoid tissue (MALT) lymphomas, which constitute the majority of Sjögren's disease-associated non-Hodgkin lymphomas. We aimed to identify reliable lymphoma predictors in patients with Sjögren's disease and study their progression over time. METHODS: In this case-control study, patients diagnosed with Sjögren's disease-associated MALT lymphoma, with a minimum of 3 years between Sjögren's disease diagnosis and MALT lymphoma diagnosis, were included from three centres specialising in Sjögren's disease (University of Athens, Athens, Greece; University of Pisa, Pisa, Italy; and University of Udine, Udine, Italy) and matched 1:1 with control participants with Sjögren's disease who did not have lymphoma according to age, sex, disease duration at last follow up, and treatment modality. Three harmonised datasets were constructed, curated, and analysed to identify MALT lymphoma predictors, representing three distinct timepoints in lymphomagenesis progression: V1 at Sjögren's disease diagnosis, V2 3-4 years before lymphoma diagnosis, and V3 0·5-1·5 years before lymphoma diagnosis. All recruited patients fulfilled the 2016 American College of Rheumatology-European League Against Rheumatism criteria for Sjögren's disease. The primary outcome was to identify MALT lymphoma predictors in Sjögren's disease, present at the timepoint of Sjögren's disease diagnosis and 3-4 years before the diagnosis of MALT lymphoma. A fast correlation-based feature selection and logistic regression model was used at V1 and V2 to identify MALT lymphoma predictors. The progression of potential predictors was studied across V1, V2, and V3. Histological parameters were not included in the analysis. An individual with lived experience of Sjögren's disease was involved in the study design. FINDINGS: 80 patients with Sjögren's disease-associated MALT lymphoma were included in the V1 dataset, 68 in the V2 dataset, and 80 in the V3 dataset, and matched to control participants with Sjögren's disease who did not have lymphoma. In both groups, 72 (90%) of 80 participants were women and eight (10%) were men. The mean age at Sjögren's disease diagnosis was 48·6 years (SD 11·6) in the lymphoma group and 48·7 years (11·5) in the control group. All patients were White, with 88 (55%) of 160 individuals of Greek nationality and 72 (45%) of Italian nationality. At the V1 timepoint, rheumatoid factor was the only independent lymphoma predictor (odds ratio 3·33 [95% CI 1·96-5·64]). At the V2 timepoint, rheumatoid factor (3·66 [95% CI 2·08-6·42]) and European League Against Rheumatism Sjögren's Syndrome Disease Activity Index ≥5 (3·88 [1·69-8·90]) were identified as independent lymphoma risk factors. The high disease activity during the transition from the V1 to V2 timepoint was attributed to specific B-cell-derived manifestations, including cryoglobulinaemia and glandular, cutaneous, and hematological manifestations. INTERPRETATION: Following up patients with high-risk of Sjögren's disease-associated MALT lymphoma based on the temporal progression of predictors presents an opportunity for early diagnosis and potential therapeutic interventions. Rheumatoid factor was the earliest and most persistent independent predictor of lymphoma. Specific B-cell manifestations in combination with rheumatoid factor indicate a more advanced stage of the lymphomagenesis process. FUNDING: European Commission-Horizon 2020.

Current Insights into Tissue Injury of Giant Cell Arteritis: From Acute Inflammatory Responses towards Inappropriate Tissue Remodeling.

Giant cell arteritis (GCA) is an autoimmune disease affecting large vessels in patients over 50 years old. It is an exemplary model of a classic inflammatory disorder with IL-6 playing the leading role. The main comorbidities that may appear acutely or chronically are vascular occlusion leading to blindness and thoracic aorta aneurysm formation, respectively. The tissue inflammatory bulk is expressed as acute or chronic delayed-type hypersensitivity reactions, the latter being apparent by giant cell formation. The activated monocytes/macrophages are associated with pronounced Th1 and Th17 responses. B-cells and neutrophils also participate in the inflammatory lesion. However, the exact order of appearance and mechanistic interactions between cells are hindered by the lack of cellular and molecular information from early disease stages and accurate experimental models. Recently, senescent cells and neutrophil extracellular traps have been described in tissue lesions. These structures can remain in tissues for a prolonged period, potentially favoring inflammatory responses and tissue remodeling. In this review, current advances in GCA pathogenesis are discussed in different inflammatory phases. Through the description of these-often overlapping-phases, cells, molecules, and small lipid mediators with pathogenetic potential are described.

FHBF: Federated hybrid boosted forests with dropout rates for supervised learning tasks across highly imbalanced clinical datasets.

Although several studies have deployed gradient boosting trees (GBT) as a robust classifier for federated learning tasks (federated GBT [FGBT]), even with dropout rates (federated gradient boosting trees with dropout rate [FDART]), none of them have investigated the overfitting effects of FGBT across heterogeneous and highly imbalanced datasets within federated environments nor the effect of dropouts in the loss function. In this work, we present the federated hybrid boosted forests (FHBF) algorithm, which incorporates a hybrid weight update approach to overcome ill-posed problems that arise from overfitting effects during the training across highly imbalanced datasets in the cloud. Eight case studies were conducted to stress the performance of FHBF against existing algorithms toward the development of robust AI models for lymphoma development across 18 European federated databases. Our results highlight the robustness of FHBF, yielding an average loss of 0.527 compared with FGBT (0.611) and FDART (0.584) with increased classification performance (0.938 sensitivity, 0.732 specificity).

Senescent cells in giant cell arteritis display an inflammatory phenotype participating in tissue injury via IL-6-dependent pathways.

OBJECTIVES: Age is the strongest risk factor of giant cell arteritis (GCA), implying a possible pathogenetic role of cellular senescence. To address this question, we applied an established senescence specific multimarker algorithm in temporal artery biopsies (TABs) of GCA patients. METHODS: 75(+) TABs from GCA patients, 22(-) TABs from polymyalgia rheumatica (PMR) patients and 10(-) TABs from non-GCA/non-PMR patients were retrospectively retrieved and analysed. Synovial tissue specimens from patients with inflammatory arthritis and aorta tissue were used as disease control samples. Senescent cells and their histological origin were identified with specific cellular markers; IL-6 and MMP-9 were investigated as components of the senescent associated secretory phenotype by triple costaining. GCA or PMR artery culture supernatants were applied to fibroblasts, HUVECs and monocytes with or without IL-6R blocking agent to explore the induction of IL-6-associated cellular senescence. RESULTS: Senescent cells were present in GCA arteries at higher proportion compared with PMR (9.50% vs 2.66%, respectively, p<0.0001) and were mainly originated from fibroblasts, macrophages and endothelial cells. IL-6 was expressed by senescent fibroblasts, and macrophages while MMP-9 by senescent fibroblasts only. IL-6(+) senescent cells were associated with the extension of vascular inflammation (transmural inflammation vs adventitia limited disease: 10.02% vs 4.37%, respectively, p<0.0001). GCA but not PMR artery culture supernatant could induce IL-6-associated senescence that was partially inhibited by IL-6R blockade. CONCLUSIONS: Senescent cells with inflammatory phenotype are present in GCA arteries and are associated with the tissue inflammatory bulk, suggesting a potential implication in disease pathogenesis.

Boosting the performance of MALT lymphoma classification in patients with primary Sjögren's Syndrome through data augmentation: a case study.

Sjögren's Syndrome (SS) patients with mucosa associated lymphoid tissue lymphomas (MALTLs) and diffuse large B-cell lymphomas (DLBCLs) have 10-year survival rates of 80% and 40%, respectively. This highlights the unique biologic burden of the two histologic forms, as well as, the need for early detection and thorough monitoring of these patients. The lack of MALTL patients and the fact that most studies are single cohort and combine patients with different lymphoma subtypes narrow the understanding of MALTL progression. Here, we propose a data augmentation pipeline that utilizes an advanced synthetic data generator which is trained on a Pan European data hub with primary SS (pSS) patients to yield a high-quality synthetic data pool. The latter is used for the development of an enhanced MALTL classification model. Four scenarios were defined to assess the reliability of augmentation. Our results revealed an overall improvement in the accuracy, sensitivity, specificity, and AUC by 7%, 6.3%, 9%, and 6.3%, respectively. This is the first case study that utilizes data augmentation to reflect the progression of MALTL in pSS.

Impact of gender and age at onset on Sjögren's syndrome presentation and outcome: state of the art.

Sjögren's syndrome (SS) is a complex and heterogeneous disease that typically affects middle-aged women. However, while it is rare, the disease may occur in male patients and in females during their childhood/adolescence or in the elderly. Contrasting data have been reported on these three subgroups clinical features and long-term outcomes. Notably, recent studies have pinpointed the severity of the disease in male patients and in both the early and the late-onset subgroups.The aim of this review is, therefore, to summarise the available evidence from the recent literature on these phenotypes. The focus will be on the clinical and laboratory features, and on the lymphoma risk observed in the three subgroups distinct phenotypes: of male patients as well as young-onset SS and elderly-onset SS. Ultimately, an accurate phenotypic stratification may represent the first step towards individualised medical approaches.

Utilisation of primary healthcare services by Sjögren's syndrome patients in the Community of Madrid and associated factors: a population-based cross-sectional study.

OBJECTIVES: To describe the utilisation of primary health care (PHC) services and factors associated with its use by patients diagnosed with Sjögren's syndrome (SS). METHODS: Population-based cross-sectional cohort of SS patients in Madrid, Spain (SIERMA). Sociodemographic, diagnostic, clinical and PHC service utilisation variables were studied by bivariate analyses and regression models. RESULTS: A total of 4,778 SS patients were included, 65.2% classified as primary SS (pSS), while 34.8% associated with another autoimmune disease (associated SS). Mean age was 64.3 years, and 92.8% of the patients were women. A total of 87.5% used PHC services, with a mean of 19.8 consultations/year. The general practitioner was the most visited health professional, with a mean of 10.9 consultations/year, followed by the nurse, with a mean of 5.7. Characteristics associated with a greater use of PHC services in SS patients were associated SS, higher adjusted morbidity groups (AMG) risk level and older age. Additional factors included symptoms such as dry mouth, fatigue, dry vagina and joint and muscle pain; comorbidities such as atrial fibrillation, diabetes, hypertension, solid malignant neoplasms, coronary heart disease and chronic obstructive pulmonary disease; and treatments such as sterile saline solution, corticosteroids, opioids and biologic disease-modifying anti-rheumatic drugs. CONCLUSIONS: Most SS patients used PHC services during the study period, and the mean number of consultations was remarkably high. Utilisation was mainly associated with AMG risk level, ageing, glandular and extra-glandular symptoms, substantial comorbidities and various treatments. An optimised design of PHC policies will facilitate early diagnosis, improved management and better quality of life for SS patients.

Tocilizumab improves clinical outcome in patients with active corticosteroid-resistant moderate-to-severe Graves' orbitopathy: an observational study.

Background: Graves' orbitopathy (GO) is an autoimmune disorder affecting the orbital fat and muscles. A significant role of IL-6 in the pathogenesis of GO has been described and tocilizumab (TCZ), an IL-6 inhibitor targeting IL-6R has been given in some patients. The aim of our case study was to evaluate the therapeutic outcome of TCZ in non-responders to first line treatments with corticosteroids. Methods: We conducted an observational study of patients with moderate to severe GO. Twelve patients received TCZ in intravenous infusions at a dose of 8mg/kg every 28 days for 4 months and followed up for additionally 6 weeks. The primary outcome was improvement in CAS by at least 2 points, 6 weeks after the last dose of TCZ. Secondary outcomes included CAS <3 (inactive disease) 6 weeks after TCZ last dose, reduced TSI levels, proptosis reduction by > 2mm and diplopia response. Results: The primary outcome, was achieved in all patients 6 weeks after treatment course. Furthermore all patients had inactive disease 6 weeks after treatment cessation. Treatment with TCZ reduced significantly median CAS by 3 units (p=0.002), TSI levels by 11.02 IU/L (p=0.006), Hertel score on the right eye by 2.3 mm (p=0.003), Hertel score on the left eye by 1.6 mm (p=0.002), while diplopia persisted in fewer patients (25%) after treatment with TCZ (not statistically significant, p=0.250). After treatment with TCZ, there was a radiological improvement in 75% of patients, while 16.7% showed no response, and in 8.3% of patients deterioration was established. Conclusion: Tocilizumab appears to be a safe and cost effective therapeutic option for patients with active, corticosteroid-resistant, moderate to severe Graves' orbitopathy.

Predicting lymphoma in Sjögren's syndrome and the pathogenetic role of parotid microenvironment through precise parotid swelling recording.

OBJECTIVE: Parotid swelling (PSW) is a major predictor of non-Hodgkin's lymphoma (NHL) in primary SS (pSS). However, since detailed information on the time of onset and duration of PSW is scarce, this was investigated to verify whether it may lead to further improved prediction. NHL localization was concomitantly studied to evaluate the role of the parotid gland microenvironment in pSS-related lymphomagenesis. METHODS: A multicentre study was conducted among patients with pSS who developed B cell NHL during follow-up and matched controls that did not develop NHL. The study focused on the history of salivary gland and lachrymal gland swelling, evaluated in detail at different times and for different durations, and on the localization of NHL at onset. RESULTS: PSW was significantly more frequent among the cases: at the time of first referred pSS symptoms before diagnosis, at diagnosis and from pSS diagnosis to NHL. The duration of PSW was evaluated starting from pSS diagnosis, and the NHL risk increased from PSW of 2-12 months to >12 months. NHL was prevalently localized in the parotid glands of the cases. CONCLUSION: A more precise clinical recording of PSW can improve lymphoma prediction in pSS. PSW as a very early symptom is a predictor, and a longer duration of PSW is associated with a higher risk of NHL. Since lymphoma usually localizes in the parotid glands, and not in the other salivary or lachrymal glands, the parotid microenvironment appears to be involved in the whole history of pSS and related lymphomagenesis.

The clinical phenotype of primary Sjögren's syndrome patients with lymphadenopathy.

OBJECTIVES: Previous cohort studies have shown that around 10% of patients with primary Sjögren's syndrome (pSS) develop lymphadenopathy during their disease course. However, no studies have described their clinical phenotype. The present study aims to describe the clinical manifestations and laboratory findings of pSS patients presenting long-standing lymphadenopathy. METHODS: From a total of 1234 consecutive pSS patients fulfilling the 2016 ACR-EULAR criteria, those with stable lymphadenopathy unrelated to lymphoma were identified (lymphadenopathy group). Their clinical data were collected and compared with 2 control groups: a) the remaining unmatched pSS patients without lymphadenopathy (unmatched non-lymphadenopathy group) and b) pSS patients without lymphadenopathy matched for age, sex, and disease duration, in an approximately 1:1 ratio (matched non-lymphadenopathy group). RESULTS: One hundred and sixty-five (13.37%) patients presented persistent, stable lymphadenopathy. They were characterised by younger age at both pSS onset and diagnosis, and by shorter disease duration. Compared to the unmatched nonlymphadenopathy group, patients with lymphadenopathy had more frequently salivary gland enlargement (p<0.001), higher focus score at first salivary gland biopsy (p=0.017), palpable purpura (p<0.001), peripheral nervous system involvement (p=0.012), glomerulonephritis (p<0.001), and leukopenia (p<0.001), while the results of the matched comparison were similar. Regarding the serological profile, the comparison with the unmatched group demonstrated higher frequency of ANA (p=0.013), anti-Ro/SSA (p=0.001), and anti-La/SSB (p<0.001) positivity for the lymphadenopathy group, while in the matched comparison only higher rates of anti-Ro/SSA positivity (p=0.002) remained statistically significant. CONCLUSIONS: pSS patients presenting non-lymphoma related stable lymphadenopathy constitute a subgroup of younger individuals with B-cell hyperactivation.

Experimental models of Sjögren's syndrome: differences and similarities with human disease.

Mouse models have been employed extensively to provide pathogenetic insights into many complex human disorders including systemic autoimmune diseases. The explosion of biotechnology and molecular biology have simplified the procedures to design and generate mouse models with the phenotype of interest. In this line, more than 30 mouse models have been proposed or developed to resemble Sjögren's syndrome (SS) in humans, in an attempt to better understand the pathophysiology of the disease and design more effective treatments. So far, none of these models has been proven an ideal recapitulation of the human disease, although each model mimics particular aspects of the human SS counterpart. This review summarises the main characteristics of the mouse models of SS that have been developed hitherto, comparing them with the human SS in terms of clinical features, sex predilection, histopathology, autoantibodies production, and propensity for lymphoma. The interpretation of these experimental models with cautiousness and the realisation of the differences between human and mouse physiology and disease pathophysiology, may render mice a useful tool to study in depth SS and reveal new therapeutic perspectives.

Clinical Phenotype and Mechanisms of Leukopenia/Neutropenia in Patients with Primary Sjögren's Syndrome.

Sjögren's syndrome (SS) is a chronic, systemic autoimmune disease which afflicts mainly the exocrine salivary and lachrymal glands, leading to mouth and eye dryness. However, any organ can be affected during the disease course, resulting in a variety of clinical manifestations. Sjögren's syndrome clinical manifestations can be classified into glandular (sicca manifestations or parotid swelling), extra-glandular, either nonspecific (arthralgias, arthritis, Raynaud's phenomenon, fatigue) or peri-epithelial (primary biliary cirrhosis, interstitial nephritis, bronchiolitis), and extra-epithelial (palpable glomerulonephritis, peripheral neuropathy, purpura). In addition, SS patients display high risk for B cell lymphomas due to chronic antigenic stimulation. Although disease pathogenesis remains unclear, genetic, environmental, and immunologic factors are implicated. In the context of systemic autoimmune manifestations, SS patients may also present with hematologic abnormalities including anaemia, leukopenia (mainly neutropenia or lymphopenia), and thrombocytopenia. Although leukopenia has been reported as a laboratory finding in many case series or cohorts of SS patients and in very few studies it has been proposed as an independent risk factor for lymphoma, the clinical phenotype of SS patients with leukopenia/neutropenia and the implicated pathogenetic mechanisms have not been elucidated. In the current study, we intend to analyse the clinical phenotype of leukopenic/neutropenic SS patients and explore the possible pathogenetic mechanisms by detecting anti-neutrophil antibodies and investigate the role of apoptotic pathways, especially the contribution of TRAIL pathway and the cFLIP molecule.

Hashimoto Thyroiditis, Anti-Parietal Cell Antibodies: Associations With Autoimmune Diseases and Malignancies.

Background: Hashimoto thyroiditis (HT) is an autoimmune disease which may result in extensive damage of the thyroid gland. Chronic atrophic gastritis (CAG), is the most frequent HT-associated disorder, with anti-parietal cell autoantibodies (APCA) being a screening test for autoimmune CAG. The aim of this study was to investigate, in a cohort of HT patients: a) the prevalence of APCA in an attempt to define their clinical phenotype and b) any possible associations of APCA with other autoimmune diseases and malignancies. Methods: This is a single-center, case-control study, conducted at a University Hospital. The study included patients with HT diagnosed between November 2017 and November 2020. Excluded were patients <18 years old, with sonographic features of HT but negative thyroid peroxidase (TPOAbs) or thyroglobulin autoantibodies (TgAbs), Graves' disease, Down or Turner's syndrome. Results: A total of 840 patients with HT were included in the study, from whom 180 (21.4%) had positive APCA. A total of 79 patients (9.4%) had one or more organ-specific autoimmune diseases and 61 (7.3%) had a systemic autoimmune disease. Autoimmune diseases were more frequent in female than in male patients (17.9% versus 10.9%, p = 0.05). APCA-positive patients were older than APCA-negative (54.1 ± 13.5 versus 49.0 ± 14.6, p <0.001) and had more often positive TPOAbs (93.3% versus 83.9%, p=0.001). Gastric neoplasms were documented only in APCA-positive patients (p <0.001). A higher frequency of organ-specific autoimmune diseases was observed in the APCA-positive group (14.4% versus 8%, p = 0.024). In the subgroup of patients with additional autoimmune diseases (n = 140), younger age and positive APCA were independently associated with the presence of organ-specific autoimmunity (OR 0.954, 95% CI 0.927-0.982 and OR 3.100, 95% CI 1.256-7.652, respectively). Papillary thyroid cancer (PTC) occurred in 3.5% of patients (26/29 women). Positive family history for thyroid autoimmunity and negative TPOAbs were the only independent risk factors for PTC among women (OR 3.228, 95% CI 1.173-8.887 and 0.315, 95% 0.113-0.881, respectively). Conclusion: This study reveals for the first time an association of APCA with organ-specific autoimmunity in HT patients. APCA together with patient age were independently associated with the presence of organ-specific autoimmunity. Finally, this study showed an association between APCA and gastric neoplasms in these patients.

Addressing the clinical unmet needs in primary Sjögren's Syndrome through the sharing, harmonization and federated analysis of 21 European cohorts.

For many decades, the clinical unmet needs of primary Sjögren's Syndrome (pSS) have been left unresolved due to the rareness of the disease and the complexity of the underlying pathogenic mechanisms, including the pSS-associated lymphomagenesis process. Here, we present the HarmonicSS cloud-computing exemplar which offers beyond the state-of-the-art data analytics services to address the pSS clinical unmet needs, including the development of lymphoma classification models and the identification of biomarkers for lymphomagenesis. The users of the platform have been able to successfully interlink, curate, and harmonize 21 regional, national, and international European cohorts of 7,551 pSS patients with respect to the ethical and legal issues for data sharing. Federated AI algorithms were trained across the harmonized databases, with reduced execution time complexity, yielding robust lymphoma classification models with 85% accuracy, 81.25% sensitivity, 85.4% specificity along with 5 biomarkers for lymphoma development. To our knowledge, this is the first GDPR compliant platform that provides federated AI services to address the pSS clinical unmet needs.

Clinical picture, outcome and predictive factors of lymphoma in primary Sjögren's syndrome: results from a harmonized dataset (1981-2021).

OBJECTIVES: Primary Sjögren's Syndrome (pSS) carries the highest risk for non-Hodgkin's lymphoma (NHL) development among systemic autoimmune diseases. However, the paucity of data on the long-term survival of those patients and the lack of established predictors for each lymphoma histologic subtype prompted our present study. METHODS: We retrospectively analysed 121 patients diagnosed with NHL according to the WHO classification criteria. All patients fulfilled the 2016 ACR-EULAR classification criteria for pSS. Cumulative clinical, laboratory, radiologic, treatment regimens and histologic data were recorded, harmonized and analysed. Overall survival (OS) and event-free survival (EFS) curves were calculated. A mucosa-associated lymphoid tissue lymphoma (MALTL) prediction model was developed by applying innovative data-driven analysis of clinical features present at the time of pSS diagnosis. RESULTS: MALTLs constituted the majority of lymphomas (92/121, 76.0%) followed by diffuse large B-cell lymphomas (DLBCL) (11/121, 9.0%) and nodal marginal zone lymphomas (NMZL) (8/121, 7%). MALTLs show salivary glands localization, limited disease and often bone marrow and nodal involvement. The 10-year OS and EFS rates were 79% and 45.5% for MALTLs, 40.9% and 24.2% for DLBCL and 46% and 31% for NMZL. Cryoglobulinemia, focus score and the total EULAR SS Disease Activity Index (ESSDAI) composite index at pSS diagnosis were proven independent MALTL predictors. Even though MALTLs have a comparatively good survival outlook, they are accompanied by frequent events throughout their clinical course. CONCLUSIONS: Common features of pSS, present at diagnosis, can predict future lymphomagenesis meriting a more intensive follow-up plan.

Neutrophil extracellular traps in giant cell arteritis biopsies: presentation, localization and co-expression with inflammatory cytokines.

OBJECTIVES: To explore the presence of neutrophil extracellular traps (NETs) in inflamed temporal artery biopsies (TABs) of patients with GCA. METHODS: Ten patients with GCA [five with limited and five with associated generalized vascular involvement, as defined by 18F-fluorodeoxyglucose PET with CT (PET/CT)] and eight with PMR were studied. The presence, location, quantitation and decoration of NETs with IL-6, IL-1ß and IL-17A were assessed in TABs at the time of disease diagnosis by tissue immunofluorescence and confocal microscopy. Paired serum levels of IL-6 and IL-17A were also evaluated in all patients. RESULTS: All temporal artery biopsies from GCA, but not PMR, patients had NETs located mainly in the adventitia, adjacent to the vasa vasorum. NETs decorated with IL-6 were present in 8/10 TABs of GCA patients, of whom 5 were PET/CT(+) and 3 PET/CT(-) patients. IL-17A(+) NETs were observed in all GCA patients. IL-1ß(+) NETs were not detected in any GCA patient. No relation was found between serum IL-6 and IL-17A levels and NETs containing IL-6 and/or IL-17A. CONCLUSIONS: NETs bearing pro-inflammatory cytokines are present in inflamed GCA-TABs. Future studies with a larger number of patients from different centres will show whether the findings regarding neutrophils/NETs in the TAB are consistent and disclose their clinical impact.

A federated AI strategy for the classification of patients with Mucosa Associated Lymphoma Tissue (MALT) lymphoma across multiple harmonized cohorts.

Mucosa Associated Lymphoma Tissue (MALT) type is an extremely rare type of lymphoma which occurs in less than 3% of patients with primary Sjögren's Syndrome (pSS). No reported studies so far have been able to investigate risk factors for MALT development across multiple cohort databases with sufficient statistical power. Here, we present a generalized, federated AI (artificial intelligence) strategy which enables the training of AI algorithms across multiple harmonized databases. A case study is conducted towards the development of MALT classification models across 17 databases on pSS. Advanced AI algorithms were developed, including federated Multinomial Naïve Bayes (FMNB), federated gradient boosting trees (FGBT), FGBT with dropouts (FDART), and the federated Multilayer Perceptron (FMLP). The FDART with dropout rate 0.3 achieved the best performance with sensitivity 0.812, and specificity 0.829, yielding 8 biomarkers as prominent for MALT development.

Combined seronegativity in Sjögren's syndrome.

OBJECTIVES: To describe the clinical spectrum of Sjögren's syndrome (SS) patients with combined seronegativity. METHODS: From a multicentre study population of consecutive SS patients fulfilling the 2016 ACR-EULAR classification criteria, patients with triple seronegativity [anti-Ro/SSA(-), anti-La/SSB(-), RF(-) and ANA(+)] and quadruple seronegativity [anti-Ro/SSA(-), anti-La/SSB(-), RF(-) and ANA(-)] were identified retrospectively. Both groups were matched in an 1:1 ratio with 2 distinct control SS groups: i) classic anti-Ro/SSA seropositive patients [SS(+)] and ii) classic anti-Ro/SSA seropositive patients with negative rheumatoid factor [SS(+)/RF(-)] to explore their effect on disease expression. Clinical, laboratory and, histologic features were compared. A comparison between triple and quadruple seronegative SS patients was also performed. REESULTS: One hundred thirty-five SS patients (8.6%) were identified as triple seronegative patients and 72 (4.5%) as quadruple. Triple seronegative patients had lower frequency of peripheral nervous involvement (0% vs. 7.2% p=0.002) compared to SS(+) controls and lower frequency of interstitial renal disease and higher prevalence of dry mouth than SS(+)/RF(-) controls. Quadruple seronegative patients presented less frequently with persistent lymphadenopathy (1.5% vs. 16.9 p=0.004) and lymphoma (0% vs. 9.8% p=0.006) compared to SS(+) controls and with lower prevalence of persistent lymphadenopathy (1.5% vs. 15.3% p=0.008) and higher frequency of dry eyes (98.6% vs. 87.5% p=0.01) and autoimmune thyroiditis (44.1% vs. 17.1% p=0.02) compared to SS(+)/RF(-) SS controls. Study groups comparative analysis revealed that triple seronegative patients had higher frequency of persistent lymphadenopathy and lymphoma, higher focus score and later age of SS diagnosis compared to quadruple seronegative patients. CONCLUSIONS: Combined seronegativity accounts for almost 9% of total SS population and is associated with a milder clinical phenotype, partly attributed to the absence of rheumatoid factor.

Serum, but Not Saliva, CXCL13 Levels Associate With Infiltrating CXCL13+ Cells in the Minor Salivary Gland Lesions and Other Histologic Parameters in Patients With Sjögren's Syndrome.

Recent studies suggest that elevated CXCL13 serum levels in patients with primary Sjögren's syndrome (pSS) associate with minor salivary gland (MSG) histologic features, disease severity, as well as high-risk status for non-Hodgkin lymphoma (NHL) development and NHL itself. In contrast, limited discriminative value of CXCL13 saliva levels has been reported. Prompt by these reports, we sought to validate the clinical utility of CXCL13 by investigating potential correlations of serum and saliva levels with MSG histopathologic [including CXCL13+-cell number, severity of infiltrates and germinal center (GC) formation], serologic and clinical parameters, as well as NHL. CXCL13 levels were evaluated in paired serum and saliva specimens of 45 pSS patients (15 with NHL; pSS-associated NHL: SSL), 11 sicca-controls (sicca-complaining individuals with negative MSG biopsy and negative autoantibody profile), 10 healthy individuals (healthy-controls) and 6 non-SS-NHLs. CXCL13+-cells were measured in paired MSG-tissues of 22 of pSS patients studied (including 7 SSLs) and all sicca-controls. CXCL13 serum levels were significantly increased in pSS and SSL patients compared to sicca- and healthy-controls and were positively correlated with the CXCL13+-cell number and biopsy focus-score. Serum CXCL13 was significantly higher in pSS patients with GCs, rheumatoid factor, hypocomplementemia, high disease activity, NHL and in high-risk patients for NHL development. CXCL13 saliva levels were significantly increased in SSL patients (compared to non-SS-NHLs), patients with GCs and in high-risk for NHL patients. Univariate analysis revealed that CXCL13 serum, but not saliva, levels were associated with lymphoma, an association that did not survive multivariate analysis. Conclusively, our findings confirm that serum, but not saliva, levels of CXCL13 are associated with histologic, serologic and clinical features indicative of more severe pSS.