Comparative single-cell multiplex immunophenotyping of therapy-naive patients with rheumatoid arthritis, systemic sclerosis, and systemic lupus erythematosus shed light on disease-specific composition of the peripheral immune system

Introduction

Systemic autoimmune diseases (SADs) are a significant burden on the healthcare system. Understanding the complexity of the peripheral immunophenotype in SADs may facilitate the differential diagnosis and identification of potential therapeutic targets.

Methods

Single-cell mass cytometric immunophenotyping was performed on peripheral blood mononuclear cells (PBMCs) from healthy controls (HCs) and therapy-naive patients with rheumatoid arthritis (RA), progressive systemic sclerosis (SSc), and systemic lupus erythematosus (SLE). Immunophenotyping was performed on 15,387,165 CD45+ live single cells from 52 participants (13 cases/group), using an antibody panel to detect 34 markers.

Results

Using the t-SNE (t-distributed stochastic neighbor embedding) algorithm, the following 17 main immune cell types were determined: CD4+/CD57- T cells, CD4+/CD57+ T cells, CD8+/CD161- T cells, CD8+/CD161+/CD28+ T cells, CD8dim T cells, CD3+/CD4-/CD8- T cells, TCRγ/δ T cells, CD4+ NKT cells, CD8+ NKT cells, classic NK cells, CD56dim/CD98dim cells, B cells, plasmablasts, monocytes, CD11cdim/CD172dim cells, myeloid dendritic cells (mDCs), and plasmacytoid dendritic cells (pDCs). Seven of the 17 main cell types exhibited statistically significant frequencies in the investigated groups. The expression levels of the 34 markers in the main populations were compared between HCs and SADs. In summary, 59 scatter plots showed significant differences in the expression intensities between at least two groups. Next, each immune cell population was divided into subpopulations (metaclusters) using the FlowSOM (self-organizing map) algorithm. Finally, 121 metaclusters (MCs) of the 10 main immune cell populations were found to have significant differences to classify diseases. The single-cell T-cell heterogeneity represented 64MCs based on the expression of 34 markers, and the frequency of 23 MCs differed significantly between at least twoconditions. The CD3- non-T-cell compartment contained 57 MCs with 17 MCs differentiating at least two investigated groups. In summary, we are the first to demonstrate the complexity of the immunophenotype of 34 markers over 15 million single cells in HCs vs. therapy-naive patients with RA, SSc, and SLE. Disease specific population frequencies or expression patterns of peripheral immune cells provide a single-cell data resource to the scientific community.

Disrupted Neural Regeneration in Dry Eye Secondary to Ankylosing Spondylitis-With a Theoretical Link between Piezo2 Channelopathy and Gateway Reflex, WDR Neurons, and Flare-Ups

This study aimed at analyzing the corneal neural regeneration in ankylosing spondylitis patients using in vivo corneal confocal microscopy in correlation with Langerhans cell density, morphology, and dry eye parameters. Approximately 24 ankylosing spondylitis subjects and 35 age- and gender-matched control subjects were enrolled. Data analysis showed that all corneal nerve-fiber descriptives were lower in the ankylosing spondylitis group, implicating disrupted neural regeneration. Peripheral Langerhans cell density showed a negative correlation with nerve fiber descriptions. A negative correlation between tear film break-up time and corneal nerve fiber total branch density was detected. The potential role of somatosensory terminal Piezo2 channelopathy in the pathogenesis of dry eye disease and ankylosing spondylitis is highlighted in our study, exposing the neuroimmunological link between these diseases. We hypothesized earlier that spinal neuroimmune-induced sensitization due to this somatosensory terminal primary damage could lead to Langerhans cell activation in the cornea, in association with downregulated Piezo1 channels on these cells. This activation could lead to a Th17/Treg imbalance in dry eye secondary to ankylosing spondylitis. Hence, the corneal Piezo2 channelopathy-induced impaired Piezo2-Piezo1 crosstalk could explain the disrupted neural regeneration. Moreover, the translation of our findings highlights the link between Piezo2 channelopathy-induced gateway to pathophysiology and the gateway reflex, not to mention the potential role of spinal wide dynamic range neurons in the evolution of neuropathic pain and the flare-ups in ankylosing spondylitis and dry eye disease.

Comparison of humoral and cellular immune responses in hematologic diseases following completed vaccination protocol with BBIBP-CorV, or AZD1222, or BNT162b2 vaccines against SARS-CoV-2

Background

Vaccination has proven the potential to control the COVID-19 pandemic worldwide. Although recent evidence suggests a poor humoral response against SARS-CoV-2 in vaccinated hematological disease (HD) patients, data on vaccination in these patients is limited with the comparison of mRNA-based, vector-based or inactivated virus-based vaccines.

Methods

Forty-nine HD patients and 46 healthy controls (HCs) were enrolled who received two-doses complete vaccination with BNT162b2, or AZD1222, or BBIBP-CorV, respectively. The antibodies reactive to the receptor binding domain of spike protein of SARS-CoV-2 were assayed by Siemens ADVIA Centaur assay. The reactive cellular immunity was assayed by flow cytometry. The PBMCs were reactivated with SARS-CoV-2 antigens and the production of activation-induced markers (TNF-α, IFN-γ, CD40L) was measured in CD4+ or CD8+ T-cells ex vivo.

Results

The anti-RBD IgG level was the highest upon BNT162b2 vaccination in HDs (1264 BAU/mL) vs. HCs (1325 BAU/mL) among the studied groups. The BBIBP-CorV vaccination in HDs (339.8 BAU/mL ***p < 0.001) and AZD1222 in HDs (669.9 BAU/mL *p < 0.05) resulted in weaker antibody response vs. BNT162b2 in HCs. The response rate of IgG production of HC vs. HD patients above the diagnostic cut-off value was 100% vs. 72% for the mRNA-based BNT162b2 vaccine; 93% vs. 56% for the vector-based AZD1222, or 69% vs. 33% for the inactivated vaccine BBIBP-CorV, respectively. Cases that underwent the anti-CD20 therapy resulted in significantly weaker (**p < 0.01) anti-RBD IgG level (302 BAU/mL) than without CD20 blocking in the HD group (928 BAU/mL). The response rates of CD4+ TNF-α+, CD4+ IFN-γ+, or CD4+ CD40L+ cases were lower in HDs vs. HCs in all vaccine groups. However, the BBIBP-CorV vaccine resulted the highest CD4+ TNF-α and CD4+ IFN-γ+ T-cell mediated immunity in the HD group.

Conclusion

We have demonstrated a significant weaker overall response to vaccines in the immunologically impaired HD population vs. HCs regardless of vaccine type. Although, the humoral immune activity against SARS-CoV-2 can be highly evoked by mRNA-based BNT162b2 vaccination compared to vector-based AZD1222 vaccine, or inactivated virus vaccine BBIBP-CorV, whereas the CD4+ T-cell mediated cellular activity was highest in HDs vaccinated with BBIBP-CorV.

Neural Regeneration in Dry Eye Secondary to Systemic Lupus Erythematosus Is Also Disrupted like in Rheumatoid Arthritis, but in a Progressive Fashion

Our objective in this study was to analyze the aberrant neural regeneration activity in the cornea by means of in vivo confocal microscopy in systemic lupus erythematosus patients with concurrent dry eye disease. We examined 29 systemic lupus erythematosus patients and 29 age-matched healthy control subjects. Corneal nerve fiber density (CNFD, the number of fibers/mm²) and peripheral Langerhans cell morphology were lower (p < 0.05) in systemic lupus erythematosus patients compared to the control group. Interestingly, corneal nerve branch density, corneal nerve fiber length, corneal nerve fiber total branch density, and corneal nerve fiber area showed a negative correlation with disease duration. A negative correlation was also demonstrated between average corneal nerve fiber density and central Langerhans cell density. This is in line with our hypothesis that corneal somatosensory terminal Piezo2 channelopathy-induced impaired Piezo2-Piezo1 crosstalk not only disrupts regeneration and keeps transcription activated, but could lead to Piezo1 downregulation and cell activation on Langerhans cells when we consider a chronic path. Hence, Piezo2 containing mechanosensory corneal nerves and dendritic Langerhans cells could also be regarded as central players in shaping the ocular surface neuroimmune homeostasis through the Piezo system. Moreover, lost autoimmune neuroinflammation compensation, lost phagocytic self-eating capacity, and lost transcription regulation, not to mention autoantibodies against vascular heparin sulfate proteoglycans and phospholipids, could all contribute to the progressive fashion of dry eye disease in systemic lupus erythematosus.

Evidence of Disruption in Neural Regeneration in Dry Eye Secondary to Rheumatoid Arthritis

The purpose of our study was to analyze abnormal neural regeneration activity in the cornea through means of confocal microscopy in rheumatoid arthritis patients with concomitant dry eye disease. We examined 40 rheumatoid arthritis patients with variable severity and 44 volunteer age- and gender-matched healthy control subjects. We found that all examined parameters were significantly lower (p < 0.05) in rheumatoid arthritis patients as opposed to the control samples: namely, the number of fibers, the total length of the nerves, the number of branch points on the main fibers and the total nerve-fiber area. We examined further variables, such as age, sex and the duration of rheumatoid arthritis. Interestingly, we could not find a correlation between the above variables and abnormal neural structural changes in the cornea. We interpreted these findings via implementing our hypotheses. Correspondingly, one neuroimmunological link between dry eye and rheumatoid arthritis could be through the chronic Piezo2 channelopathy-induced K_2P-TASK1 signaling axis. This could accelerate neuroimmune-induced sensitization on the spinal level in this autoimmune disease, with Langerhans-cell activation in the cornea and theorized downregulated Piezo1 channels in these cells. Even more importantly, suggested principal primary-damage-associated corneal keratocyte activation could be accompanied by upregulation of Piezo1. Both activation processes on the periphery would skew the plasticity of the Th17/Treg ratio, resulting in Th17/Treg imbalance in dry eye, secondary to rheumatoid arthritis. Hence, chronic somatosensory-terminal Piezo2 channelopathy-induced impaired Piezo2-Piezo1 crosstalk could result in a mixed picture of disrupted functional regeneration but upregulated morphological regeneration activity of these somatosensory axons in the cornea, providing the demonstrated abnormal neural corneal morphology.

Assessment of the right ventricular-pulmonary circulation unit during stress in ankylosing spondylitis and psoriatic arthritis patients

Background

Cardiopulmonary complications are common in ankylosing spondylitis (AS) and arthritis psoriatica (APs), which have an unfavourable impact on mortality and quality of life. APs may be connected with pulmonary hypertension, while AS is linked to interstitial lung disease and chest wall restriction.

We aimed to assess the response of the pulmonary circulation unit during stress in AS and APs patients.

Methods

A total of 71 patients were enrolled in the study: 28 of them had AS (age 50.8±11.8 years), 17 APs (age 52.1±13.5 years), and 26 were healthy individuals (age 54.23±9.9 years). To the maximally tolerated workload, all subjects underwent resting and exercise stress echocardiography on a supine bicycle ergometer. Echocardiographic measurements were taken at rest, at 50 watts workload, and at maximal exercise.

Results

AS patients had significantly higher pulmonary artery systolic pressure (PASP; AS: 32.6±16.8 mmHg, APs: 21.6±12.7 mmHg, p&lt;0.05) and pulmonary vascular resistance (PVR; AS: 1.3±0.4 WU, PsA: 1.1±0.3 WU, p&lt;0.05) at maximal workload, while the right ventricular-pulmonary arterial (RV-PA) coupling at peak stress was higher in APs patients (AS: 1.2±0.6 mm/mmHg, PsA: 1.8±1.1 mm/mmHg, p&lt;0.05). Comparing to the control group, AS and PsA patients had significantly higher resting PASP (control: 12.6±6.4 mmHg; AS: 22.8±7.6 mmHg, p&lt;0.001; PsA: 21.4±7.0 mmHg, p&lt;0.001), lower resting RV-PA coupling (control: 2.7±1.4 mm/mmHg; AS: 1.3±0.4, p&lt;0.001; PsA 1.3±0.4 mm/mmHg, p&lt;0.001), and higher peak PVR (control: 0.6±0.4 WU; AS: 1.3±0.4, p&lt;0.001; PsA: 1.1±0.3 WU, p&lt;0.005). One-way analysis of variance of the three groups also showed significant differencies in the resting PASP (p&lt;0.001), peak PASP (p&lt;0.05), resting RV-PA coupling (p&lt;0.001), peak PVR (p&lt;0.001).

Conclusion

Stress echocardiography is a promising, radiation-free method for assessing the subclinical cardiopulmonary changes among AS and PsA patients. The changes of PVR during stress may highlight the pulmonary complications in the subclinical stage.

Funding Acknowledgement

Type of funding sources: None.

Trends in Opioid Utilisation in Hungary, 2006-2020: A Nationwide Retrospective Study with Multiple Metrics

BACKGROUND

Opioid use is well-documented in several countries: some countries struggle with overuse while others have almost no access to opioids. For Europe, limited data are available. This study analysed Hungarian opioid utilisation in ambulatory care between 2006 and 2020.

METHODS

We obtained national drug utilization data on reimbursed opioid analgesics (ATC code: N02A) from a national health insurance database for a 15-year period. We investigated utilisation trends, using three volume-based metrics (defined daily dose per 1000 inhabitants per day (DID), oral morphine equivalent per 1000 inhabitants per day, packages dispensed per 1000 inhabitants per year). We stratified data based on administration routes, analgesic potency and reimbursement categories.

RESULTS

Total opioid utilisation increased during the study period according to all three metrics (74% in DID) and reached 5.31 DID by 2020. Upward trends were driven by an increase both in weak and strong opioid use (79% vs. 53%). The most commonly used opioids were fentanyl (in the strong category; 0.76 DID in 2020) and tramadol (in the weak category; 2.62 DID in 2020). Overall, tramadol was also the most commonly used opioid throughout the study period. Oral administration of opioid medications was dominant. Based on reimbursement categories, musculoskeletal pain was becoming a more frequent indication for opioid use (1552% increase in DID), while opioid use for cancer pain declined significantly during the study period (-33% in DID).

CONCLUSIONS

Our low utilisation numbers might indicate underuse of opioid analgesia, especially for cancer pain.

Humoral and Cellular Immunogenicity and Safety of Five Different SARS-CoV-2 Vaccines in Patients With Autoimmune Rheumatic and Musculoskeletal Diseases in Remission or With Low Disease Activity and in Healthy Controls: A Single Center Study

Background

Vaccine-induced immunity is essential for controlling the COVID-19 pandemic. Data on humoral and cellular immunogenicity and safety of different SARS-CoV-2 vaccines in patients with autoimmune rheumatic and musculoskeletal diseases (RMDs) are limited.

Methods

A single center observational study evaluated the immunogenicity and safety of the two-dose regimen of the BBIBP-CorV inactivated, Gam-COVID-Vac and AZD1222 adenovirus-based, and BNT162b2 and mRNA-1273 mRNA-based vaccines in patients with RMDs (n = 89) compared with healthy controls (n = 74). Neutralizing anti-RBD (receptor binding domain) specific antibodies and SARS-CoV-2 specific T-cell response were measured one and four months after the second vaccine dose in parallel with vaccination efficacy and safety.

Results

Disease-specific comparison showed that antibody response at four months was higher in spondylarthropathies compared to rheumatoid arthritis and autoimmune RMDs. Risk factors for reduced immunogenicity included longer disease duration, positive immunoserological profile and anti-CD20 therapy of patients. The rate of positive anti-RBD antibody response for healthy controls versus patients after 4 months post vaccination was 69% vs. 55% for the inactivated viral vaccine BBIBP-CorV, 97% vs. 53% for the pooled data of adenovirus vector-based vaccines Gam-COVID-Vac and AZD1222, or 100% vs. 81% for the pooled data of mRNA vaccines BNT162b2 and mRNA-1273, respectively. Patients who received the Gam-COVID-Vac or mRNA-1273 vaccines had a higher proportion of TNF-α producing CD4+ T-cells upon SARS-CoV-2 antigen stimulation compared to the inactivated viral vaccine.

Conclusion

All five investigated vaccines were immunogenic in the majority of patients and healthy controls with variable antibody and T-cell response and an acceptable safety profile.

Disease status in human and experimental arthritis, and response to TNF blockade, is associated with MHC class II invariant chain (CD74) isoform expression

Splice variants of CD74 differentially modulate the activity of cathepsin L (CTSL). As CD74 and CTSL participate in the pathogenesis of inflammatory diseases such as rheumatoid arthritis (RA), we determined whether splice variants of CD74 could be biomarkers of disease activity. Gene expression was measured in mice with collagen-induced arthritis using quantitative PCR (qPCR). In vitro studies using murine macrophage/DC-lineage cells determined the relative influence of macrophage phenotype on isoform expression and the potential to produce CTSL in response to TNF. CD74 splice variants were measured in human RA synovium and RA patients' monocytes. In arthritic mice, the expression of the p41 CD74 isoform was significantly higher in severely affected paws compared with unaffected paws or the paws of naïve mice; the p41 isoform significantly correlated with the expression of TNF in arthritic paws. Compared with M2-like macrophages, M1-like macrophages expressed increased levels of CD74 and had higher expression, secretion and activity of CTSL. RA patients that responded to TNF blockade had significantly higher expression levels of CD74 in circulating monocytes after treatment, compared with non-responders. The expression of the human CD74 isoform a was significantly higher in RA synovia, compared with osteoarthritis synovia, and was associated with CSTL enzymatic activity. This study is the first to demonstrate differential expression of the CD74 p41 isoform in an auto-immune disorder and in response to therapy. The differential expression of CD74 splice variants indicates an association, and potentially a mechanistic role, in the pathogenesis of RA.

Assessment of pulmonary circulation unit during exercise in patients with ankylosing spondilitis and sporiatic arthritis

Funding Acknowledgements

Type of funding sources: None.

Background  Ankylosing spondylitis (AS) and psoriatic arthritis (PsA) are chronic multisystem inflammatory disorders that present with articular and extra-articular features. Cardiac dysfunction and pulmonary disease are well-known and commonly reported extra-articular manifestations of AS and PsA.  The inflammatory process can induce respiratory complications, including chest wall restriction, significantly impacting patients" cardiorespiratory status.

We aimed to assess pulmonary circulation and right ventricle behaviour during exercise in patients with AS and PsA and to detect the possible effect of chest wall restriction on right heart function.

Methods  A total of 45 spondylarthritis patients were enrolled in the study (age 51.5 ± 12.3 years, 82.2% men): 27 of them were diagnosed with AS (20 of them had ankylosis at the time of the study), while 18 had PsA (2 of them in ankylosis). According to a standardized protocol, all subjects underwent resting and exercise stress echocardiography on a semi-recumbent cycle ergometer with an incremental workload up to the maximal tolerated workload. Basic echocardiographic measurements were taken, focusing on the right and left ventricular functions and the systolic pulmonary artery pressure (PASP) at rest, at 50 watts workload, and maximal exercise. During the examination, non-invasive blood pressure measurements, transcutaneous capillary oxygen saturation and continuous ECG recording were performed. 

Results PASP did not differ between the AS and PsA patients at rest (15.6 ± 6.7 mmHg vs 13.7 ± 8.3 mmHg; p = ns); however, PASP measured at the maximal workload was significantly higher among AS patients  (31.4 ± 15.9mmHg vs 21.6 ± 12.7mmHg; p &lt; 0.05; Figure 1). PASP did not correlate with the age or the time that passed since the diagnosis. Parameters describing the left and right ventricular systolic and diastolic function did not differ significantly between AS and PsA patients at rest and peak stress. Comparing the LV diastolic parameters of ankylosing patients with non-ankylosing patients irrespective of the underlying disease showed significantly different values in peak E/e"ratio (8.9 ± 3 vs 7.4 ± 1.6; p &lt; 0,05; Figure 2).

Conclusion  Exercise stress echocardiography is a promising diagnostic modality in autoimmune diseases. In AS patients, the chest wall restriction may results in elevation of PASP during the exercise. The noninvasive indice of left ventricular filling pressure increases significantly in patients with ankylosis in both groups, explaining the effect of the rigid chest wall on the left ventricular filling. Abstract Figure.  Abstract Figure.

Integrative Analysis Reveals a Molecular Stratification of Systemic Autoimmune Diseases

OBJECTIVE

Clinical heterogeneity, a hallmark of systemic autoimmune diseases, impedes early diagnosis and effective treatment, issues that may be addressed if patients could be classified into groups defined by molecular pattern. This study was undertaken to identify molecular clusters for reclassifying systemic autoimmune diseases independently of clinical diagnosis.

METHODS

Unsupervised clustering of integrated whole blood transcriptome and methylome cross-sectional data on 955 patients with 7 systemic autoimmune diseases and 267 healthy controls was undertaken. In addition, an inception cohort was prospectively followed up for 6 or 14 months to validate the results and analyze whether or not cluster assignment changed over time.

RESULTS

Four clusters were identified and validated. Three were pathologic, representing "inflammatory," "lymphoid," and "interferon" patterns. Each included all diagnoses and was defined by genetic, clinical, serologic, and cellular features. A fourth cluster with no specific molecular pattern was associated with low disease activity and included healthy controls. A longitudinal and independent inception cohort showed a relapse-remission pattern, where patients remained in their pathologic cluster, moving only to the healthy one, thus showing that the molecular clusters remained stable over time and that single pathogenic molecular signatures characterized each individual patient.

CONCLUSION

Patients with systemic autoimmune diseases can be jointly stratified into 3 stable disease clusters with specific molecular patterns differentiating different molecular disease mechanisms. These results have important implications for future clinical trials and the study of nonresponse to therapy, marking a paradigm shift in our view of systemic autoimmune diseases.

Urine soluble urokinase plasminogen activator receptor as a potential biomarker of lupus nephritis activity

There is a lack of non-invasive biomarkers to identify lupus nephritis (LN). Soluble urokinase plasminogen activator receptor (suPAR) is a sensitive biomarker of ongoing inflammation and a potential marker of podocyte dysfunction. The aim of this study was to assess urine and plasma suPAR in LN. 14 systemic lupus erythematosus (SLE) patients with newly diagnosed LN, 8 active SLE patients (SLEDAI >8) without LN and 31 healthy individuals were enrolled. Urine and plasma samples were taken before the initiation of LN induction therapy, and monthly thereafter. Global and renal disease activity were defined using the SLEDAI-2K and the SLEDAI-2K renal domain score, respectively. suPAR concentrations were measured with the suPARnostic Flex ELISA assay. Urine and plasma suPAR levels were elevated in SLE patients with active LN compared with resolved LN and healthy controls. Urine suPAR levels were comparable to healthy controls in active SLE without LN. Urine and plasma suPAR levels were higher before than after the initiation of LN induction therapy. Prospective follow-up measurements also suggested that urine suPAR levels raised again in patients with a relapse of LN according to SLEDAI-2K renal domain score, whereas plasma suPAR levels did not correlate with renal disease activity. Urine suPAR is a promising LN activity biomarker, given its isolated elevation in urine in active LN and pronounced decrease with LN improvement.

Kynurenic Acid Analog Attenuates the Production of Tumor Necrosis Factor-α, Calgranulins (S100A 8/9 and S100A 12), and the Secretion of HNP1-3 and Stimulates the Production of Tumor Necrosis Factor-Stimulated Gene-6 in Whole Blood Cultures of Patients With Rheumatoid Arthritis

Objectives: Rheumatoid arthritis (RA) is a chronic, inflammatory joint disease with complex pathogenesis involving a variety of immunological events. Recently, it has been suggested that kynurenic acid (KYNA) might be a potential regulator of inflammatory processes in arthritis. KYNA has a definitive anti-inflammatory and immunosuppressive function. The aim of the present study is to investigate the complex effects of a newly synthesized KYNA analog—SZR72 on the in vitro production of tumor necrosis factor-α (TNF-α), tumor necrosis factor-stimulated gene-6 (TSG-6), calprotectin (SA1008/9), SA100 12 (EN-RAGE), and HNP1–3 (defensin-α) in the peripheral blood of patients with RA and the various effects of the disease.

Methods: Patients with RA (n = 93) were selected based on the DAS28 score, medication, and their rheumatoid factor (RF) status, respectively. Peripheral blood samples from 93 patients with RA and 50 controls were obtained, and activated by heat-inactivated S. aureus. Parallel samples were pretreated before the activation with the KYNA analog N-(2-N, N-dimethylaminoethyl)-4-oxo-1H-quinoline-2-carboxamide hydrochloride. Following the incubation period (18 h), the supernatants were tested for TNF-α, TSG-6, calprotectin, S100A12, and HNP1–3 content by ELISA.

Results: SZR72 inhibited the production of the following inflammatory mediators: TNF-α, calprotectin, S100A12, and HNP1–3 in whole blood cultures. This effect was observed in each group of patients in various phases of the disease. The basic (control) levels of these mediators were higher in the blood of patients than in healthy donors. In contrast, lower TSG-6 levels were detected in patients with RA compared to healthy controls. In addition, the KYNA analog exerted a stimulatory effect on the TSG-6 production ex vivo in human whole blood cultures of patients with RA in various phases of the disease.

Conclusion: These data further support the immunomodulatory role of KYNA in RA resulting in anti-inflammatory effects and draw the attention to the importance of the synthesis of the KYNA analog, which might have a future therapeutic potential.

Calcium Influx Kinetics and the Characteristics of Potassium Channels in Peripheral T Lymphocytes in Systemic Sclerosis

BACKGROUND

Systemic sclerosis (SSc) is a chronic, immune-mediated, connective tissue disease causing microvascular abnormalities and fibrosis. The cytoplasmic calcium influx kinetics in T lymphocytes governs lymphocyte activation in this inflammatory process. The inhibition of Kv1.3 and IKCa1 potassium channels reduces calcium influx.

METHODS

This study aimed to analyze cytoplasmic calcium influx kinetics following activation in Th1, Th2, and CD8 cells in peripheral blood of 12 healthy individuals and 16 patients with systemic sclerosis using flow cytometry. We also evaluated the effect of the specific inhibition of the Kv1.3 and IKCa1 potassium channels.

RESULTS

We observed higher levels of activation in CD8 compared with Th1 cells in SSc. However, the activation of CD8 cells was lower in SSc compared to healthy controls. Moreover, activation of Th1 lymphocytes was slower in SSc than in healthy controls. The inhibition of IKCa1 channels decreased the activation of Th1 cells, while the inhibition of Kv1.3 channels modified the dynamics of activation of Th1 and Th2 lymphocytes in SSc.

CONCLUSION

Th1 and CD8 cells demonstrate specific activation dynamics and sensitivity to potassium channel inhibition in SSc, distinguishing this condition both from healthy controls and other autoimmune diseases.

AB0107 INVESTIGATION OF THE EFFECTS OF KYNURENIC ACID ANALOGS IN RHEUMATOID ARTHRITIS

Background:

The investigation of anti-inflammatory and immunosuppressive functions of kynurenic acid (KYNA) is now in focus. Previously, we demonstrated the opposite effects of KYNA and different KYNA analogs on tumor necrosis factor-α (TNF-α) production and tumor necrosis factor-stimulated gene-6 (TSG-6) expression in U-937 monocytic cells. The potential effect of KYNA analogs on further immune mediators including alarmins (S100A12=EN-RAGE and S100A8/9=calprotectin), and on human neutrofil peptide 1-3(α-defensin) production has not been investigated.

Objectives:

Therefore, in the present study, we compared the effects of newly synthesized KYNA analog on the TNF-α, alarmins and α-defensin production, correlation with the effects on the TSG-6 expression in rheumatoid arthritis (RA).

Methods:

93 RA patients were involved and divided subgroups based on DAS28 activity score. Peripheral blood mononuclear cells (PBMC) was isolated from RA patients and healthy controls. As cytokine inducers heat inactivatedStaphylococcus aureus(SA1) were used. In parallel in vitro experiments, the SA1 induced PBMCs were pretreated with a newly synthesized KYNA analog (compound SZR-72 was synthesized by direct amidation of KYNA). The concentrations of the above mentioned inflammatory mediators in the supernatants were quantified by using ELISA kits and the TSG-6 expression was also determined by RTqPCR method.

Results:

The SA1 induced TNF-α, EN-RAGE, calprotectin and α-defensin production was significantly higher in RA patients’ group than in healthy controls. KYNA analog attenuated the SA1 induced TNF-α, EN-RAGE, calprotectin and α-defensin production, and increased TSG-6 production and TSG-6 mRNA expression in PBMC cells from RA patients. The SA1 induced TNF-α and TSG-6 production correlated with the DAS28 activity score. The TNF-α inhibitory effect of the KYNA analog correlated inversely with the TSG-6 stimulatory effect in all subgroups of RA patients based on DAS28 activity score.

Conclusion:

TSG-6 expression could participate in the suppression of inflammatory cytokines, such as TNF-α, EN-RAGE, calprotectin and α-defensin. We suppose that the elevation of the TSG-6 expression by KYNA and especially by new KYNA analogs might be one of the mechanisms that are responsible for their suppressive effect on TNF-α production as a feedback mechanism in RA. KYNA and KYNA analogs have an important role in influencing TSG-6 expression, and there is a possible benefit with potential therapeutic consequence of targeting TSG-6 expression by kynurenines in inflammatory conditions in RA.

References:

[1]Mándi Y, Endrész V, Mosolygó T, Burián K, Lantos I, Fülöp F, Szatmári I, Lőrinczi B, Balog A, Vécsei L, The Opposite Effects of Kynurenic Acid and Different Kynurenic Acid Analogs on Tumor Necrosis Factor-a (TNF-a) Production and Tumor Necrosis Factor-Stimulated Gene-6 (TSG-6) Expression. Frontiers in Immunology. doi: 10.3389/fimmu.2019.01406

Acknowledgments:

This work was supported by GINOP 2.3.2-2015-16-00034

Disclosure of Interests:

None declared

Specific T-Cell Subsets Can Predict the Efficacy of Anti-TNF Treatment in Inflammatory Bowel Diseases

The effect of TNF-blockers on T-lymphocyte subsets is largely unknown in inflammatory bowel diseases (IBDs). The aim of the present study was to analyze the prevalence of T-cell subtypes and their correlation to therapeutic response. Sixty-eight patients with Crohn’s disease (CD), 46 with ulcerative colitis (UC) were enrolled. (1) The clinical course was followed after the initiation of TNF-blockers (prospective study). (2) The immunophenotype was also compared between long-term anti-TNF treated-responders and non-responders (cross-sectional study). The results were compared with those of therapy-naïve patients with active disease and those in remission with non-biological immunosuppressive therapy, and with healthy controls. Fourteen subtypes of peripheral blood T cells were measured with flow cytometry. The prevalence of Th2 and Th17 cells, of HLA-DR- and CD69-positive CD4 and CD8 cells, was higher, whereas the percentage of CD45RA-positive CD4 and CD8 cells was lower in both IBDs than in controls. CD8CD69 cell frequency was lower in remission, and decreased during anti-TNF therapy in CD responders. CD8CD45RO memory cells had higher prevalence in UC non-responders than in those starting anti-TNF. CD4CD45RO percentage < 49.05 at the initiation of TNF-blockers was predictive of a subsequent therapeutic response in CD, and Th2 and Th17 prevalence correlated with the duration of remission on TNF-blockers in UC. This study provided a detailed description of the T-cell composition in IBDs. CD8CD69 prevalence may be an activity marker in CD, and CD4CD45RO, Th2 and Th17 levels could be predictive for a therapeutic response to anti-TNF.

'Bottom-up' effects in a tritrophic plant-aphid-parasitoid system: Why being the perfect host can have its disadvantages

In this study the host plant genotype effect on cabbage aphid, Brevicoryne brassicae (L.)(Hemiptera: Aphididae) preference and performance, the effect of aphid genotype on parasitoids performance, as well as the indirect effects of plant genotypes on aphid parasitoid performance, were tested using different population samples of the aphid and its primary endoparasitoid wasp, Diaeretiella rapae (M'Intosh) (Hymenoptera: Braconidae). Experiments were run as fully-factorial randomized block design in a greenhouse. Accordingly, host plant cultivar had significant effects on the total number of aphids and aphid-load whilst the fitness of the aphid genotypes were also influenced by plant cultivar. The effect of parasitism on cabbage aphids was significantly different between plant cultivars. Overall, the results revealed that cabbage aphid is under different selective pressures arising from both higher (parasitoid) and lower (host plant cultivar) trophic levels. The host plant cultivar had a significant effect on both aphid fitness and parasitism rate on particular aphid genotypes. This indicates that host-plant-adapted aphid species can create much context-dependency in the nature and strength of 'fitness benefits parasitism', which may in turn alter the costs and benefits of host specialization.

The Opposite Effects of Kynurenic Acid and Different Kynurenic Acid Analogs on Tumor Necrosis Factor-α (TNF-α) Production and Tumor Necrosis Factor-Stimulated Gene-6 (TSG-6) Expression

Purpose: The investigation of anti-inflammatory and immunosuppressive functions of Kynurenic acid (KYNA) is now in focus. There is also substantial evidence that TSG-6 has an anti-inflammatory activity. Therefore, in the present study, we compared the effects of newly synthetized KYNA analogs on the TNF-α production in U-937 monocytic cells in correlation with the effects on the TSG-6 expression.

Methods: TNF-α production was measured by ELISA, the TSG-6 expression was determined by RTqPCR method. As cytokine inducers Staphylococcus aureus and Chlamydia pneumoniae were used.

Results: KYNA and KYNA analogs attenuated TNF-α production and increased TSG-6 mRNA expression in U-937 cells stimulated by heat inactivated Staphylococcus aureus. In contrast, KYNA and some of the KYNA analogs increased the TNF-α production of C. pneumoniae infected U-937 cells; however, the newly synthetized analogs (SZR104, SZR 105, and SZR 109) exerted significant inhibitory effects on the TNF-α synthesis. The inhibitory and stimulatory effects correlated inversely with the TSG-6 expression.

Conclusions: TSG-6 expression following activation with bacterial components could participate in the suppression of inflammatory cytokines, such as TNF-α, We suppose that the elevation of the TSG-6 expression by KYNA and especially by new KYNA analogs might be one of the mechanisms that are responsible for their suppressive effect on TNF-α production as a feedback mechanism. KYNA and KYNA analogs have an important role in influencing TSG-6 expression, and there is a possible benefit of targeting TSG-6 expression by kynurenines in inflammatory conditions following infections.

Amelioration of Autoimmune Arthritis in Mice Treated With the DNA Methyltransferase Inhibitor 5'-Azacytidine

OBJECTIVE

Disease-associated, differentially hypermethylated regions have been reported in rheumatoid arthritis (RA), but no DNA methyltransferase inhibitors have been evaluated in either RA or any animal models of RA. The present study was conducted to evaluate the therapeutic potential of 5'-azacytidine (5'-azaC), a DNA methyltransferase inhibitor, and explore the cellular and gene regulatory networks involved in the context of autoimmune arthritis.

METHODS

A disease-associated genome-wide DNA methylation profile was explored by methylated CpG island recovery assay-chromatin immunoprecipitation (ChIP) in arthritic B cells. Mice with proteoglycan-induced arthritis (PGIA) were treated with 5'-azaC. The effect of 5'-azaC on the pathogenesis of PGIA was explored by measuring serum IgM and IgG1 antibody levels using enzyme-linked immunosorbent assay, investigating the efficiency of class-switch recombination (CSR) and Aicda gene expression using real-time quantitative polymerase chain reaction, monitoring germinal center (GC) formation by immunohistochemistry, and determining alterations in B cell subpopulations by flow cytometry. The 5'-azaC-induced regulation of the Aicda gene was explored using RNA interference, ChIP, and luciferase assays.

RESULTS

We explored arthritis-associated hypermethylated regions in mouse B cells and demonstrated that DNA demethylation had a beneficial effect on autoimmune arthritis. The 5'-azaC-mediated demethylation of the epigenetically inactivated Ahr gene resulted in suppressed expression of the Aicda gene, reduced CSR, and compromised GC formation. Ultimately, this process led to diminished IgG1 antibody production and amelioration of autoimmune arthritis in mice.

CONCLUSION

DNA hypermethylation plays a leading role in the pathogenesis of autoimmune arthritis and its targeted inhibition has therapeutic potential in arthritis management.

The Impact of Anti-TNF Therapy on CD4+ and CD8+ Cell Subsets in Ankylosing Spondylitis

OBJECTIVES

Ankylosing spondylitis (AS) is a chronic, progressive immune-mediated inflammatory disease, driven primarily by Th1 and Th17 cells. Anti-TNF therapies are successfully used in AS to achieve and maintain remission. However, their influence on the composition of T-cell subsets is not clear. We aimed to characterize the changes in the T-cell repertoire after a long-term anti-TNF treatment in AS patients.

METHODS

Twenty-two AS patients under long-term anti-TNF therapy were evaluated (15 anti-TNF responders and 7 nonresponders). A wide range of cell subtypes was analyzed with flow cytometry and compared with therapy-naïve and short-term data too.

RESULTS

Key findings include decreased proportions of naïve CD4 and CD8 cells, increased frequencies of Th1 and Th17 cells and higher Th1/Th2 ratios in the long-term anti-TNF-treated patients (responders, nonresponders and total), which was found to be significant not only when compared with healthy controls, but also with therapy-naïve and short-term anti-TNF-treated AS patients. We noted several alterations within the various activated T-cell subsets - increase in CD4HLADR cells in responders, in CD8HLADR cells in the whole AS group and in responders, and in CD4CD25 cells in responders, and decrease in CD4CD69 cell percentages in long-term treated patients - becoming evident only after long-term anti-TNF therapy.

CONCLUSIONS

This study provides a comprehensive assessment of the impact of anti-TNF therapy on the T-cell repertoire in AS. Changes in T-cell phenotype seem to develop progressively during therapy, even in inactive disease, and reflect an ongoing effector T-cell differentiation and activation, along with the parallel compensatory increase in regulatory T cells.

Characterization of the thrombin generation profile in systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is a multisystemic inflammatory autoimmune disorder. Thrombotic events occur at a higher incidence among SLE patients. The investigation of thrombin generation (TG) with calibrated automated thrombogram (CAT) test as a global hemostasis assay is applicable for the overall functional assessment of the hemostasis. The aim of this study was to characterize the hemostatic alterations observed in SLE by CAT assay. In this study, CAT parameters and basic coagulation parameters of SLE patients (n = 22) and healthy control subjects (n = 34) were compared. CAT area under the curve (i.e., endogenous thrombin potential) was lower than normal in SLE (807 vs. 1,159 nM*min, respectively), whereas other CAT parameters (peak, lag time, time to peak, and velocity index) and the basic coagulation tests were within the normal range. The presence of anti-phospholipid antibodies and the applied therapy was not associated with hemostasis parameters in SLE. We concluded that the reported high risk of thrombosis is not related to TG potential.

The effects of Kv1.3 and IKCa1 channel inhibition on cytokine production and calcium influx of T lymphocytes in rheumatoid arthritis and ankylosing spondylitis

Kv1.3 and IKCa1 lymphocyte potassium channels have been implicated as important targets of selective immunomodulation. We compared the alterations in cytokine production upon selective inhibition of Kv1.3 or IKCa1 channels (by MGTX and TRAM, respectively) in healthy donors (HD), RA and AS patients. We also determined calcium influx kinetics and its sensitivity to Kv1.3 and IKCa1 channel inhibition following PHA activation in CD4, Th1, Th2 and CD8 cells as well as monocytes. The application of TRAM resulted in a lower production of TNF-a and IL1-RA in all three study groups. Inhibition by TRAM had contrary effects on the production of IL-1b and IL-5: While their production was increased by PBMCs of RA patients, this effect was not observed in HD and AS PBMCs. While treatment with MGTX resulted in a similar decrease in calcium influx in the CD4 and Th2 subsets across all study groups, TRAM treatment had opposite effects on RA and HD samples: It decreased calcium influx in the Th2 and CD8 subsets in RA, while only Th1 cells were affected in HDs. The effects of IKCa1 channel inhibition are controversial in samples of RA and AS patients, since it shifts the inflammatory balance into the pro-inflammatory direction.

Postural control in degenerative diseases of the hip joint

BACKGROUND

Few studies investigated the postural control in patients with hip joint impairments; in some cases, balance impairments have been found, while other researchers have seen no significant changes. The goal of this study was to characterize postural stability in patients suffering from unilateral osteoarthritis or rheumatoid arthritis in different balance tasks and to reveal potential differences between the two diseases in this respect.

METHODS

Ten patients with hip osteoarthritis (mean age: 62.3years), 10 patients with rheumatoid arthritis (mean age: 55.4years) and 10 healthy control subjects (mean age: 54.3years) took part in the study. Displacement of centre of pressure was measured with a force plate in mediolateral and anteroposterior directions during two-leg standing on firm and compliant surfaces with eyes opened and closed.

FINDINGS

Standing on a firm surface sway path increased significantly in the anteroposterior direction in both patient groups and in the mediolateral direction in all groups with eyes closed as compared to eyes opened condition. Standing on a compliant surface, sway paths increased significantly in both directions in all groups with eyes closed as compared to eyes opened condition; furthermore, sway paths were significantly longer with eyes closed in patients with rheumatoid arthritis in comparison with control and osteoarthritis groups.

INTERPRETATION

Our data revealed that the manipulation of both visual and somatosensory information can reveal subtle impairments in balance control. Thus, this paradigm can unmask the effects of decreased proprioception due to joint capsule lesion in patients with rheumatoid arthritis.

The Clinical Value of Soluble Urokinase Plasminogen Activator Receptor (suPAR) Levels in Autoimmune Connective Tissue Disorders

The assessment of the general inflammatory condition of patients with autoimmune connective tissue disorders (ACTD) is a major challenge. The use of traditional inflammatory markers including CRP-levels and erythrocyte sedimentation rate (ESR) is limited by several preanalytical factors and their low specificities. Soluble urokinase plasminogen activator receptor (suPAR) is one of the novel candidate markers that is increasingly used in immune mediated disorders. In our studies we compared suPAR levels of patients with rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), systemic sclerosis (SSc) and ankylosing spondylitis with those of healthy controls. suPAR provided valuable clinical information on disease activity in RA, SLE and SSc. We identified a subgroup of remitted RA patients, who presented still clinical symptoms of inflammatory activity which correlated to high plasma suPAR (while ESR and CRP were normal). In SLE we established specific suPAR cut-off values that support the discrimination between patients with high and those with moderate SLE activity. In patients with SSc suPAR correlated with objective measures of lung and other complications. In the majority of ACTDs including SLE, SSc or RA, suPAR is seemingly a good biomarker that would provide valuable clinical information. However, before the introduction of this novel parameter in laboratory repertoire important issues should be elucidated. These include the establishment of appropriate and disease specific cutoff values, clarification of interfering preanalytical values and underlying conditions and declaration of age- and gender-specific reference ranges.

Increased plasma soluble urokinase plasminogen activator receptor levels in systemic sclerosis: possible association with microvascular abnormalities and extent of fibrosis

Urokinase plasminogen activator receptor (uPAR) is a key component of the fibrinolytic system involved in extracellular matrix remodeling and angiogenesis. Novel animal models supported the key role of uPAR not only in fibrosis but also in systemic sclerosis (SSc)-related microvascular abnormalities. The aim of this study was to investigate plasma soluble uPAR (suPAR) levels in SSc, and their association with organ-specific involvement.

suPAR concentrations were measured by ELISA in SSc patient (n=83) and in healthy controls (n=29). Simultaneously, CRP and ESR were assessed. Detailed clinical data including skin, lung, heart and microvascular characteristics were evaluated at sampling.

suPAR values were higher in SSc patients than in controls. Subgroup analysis showed higher suPAR values in diffuse cutaneous- than in limited cutaneous SSc and correlated with anti-Scl-70+. suPAR levels also associated with pulmonary function test parameters of fibrosis, presence of microvascular lesions (e.g., Raynaud phenomenon, naifold capillaroscopic abnormalities and digital ulcers) and arthritis.

Our data indicate that suPAR might be a valuable early diagnostic marker of SSc which also correlates with disease severity.

Soluble urokinase plasminogen activator receptor (suPAR) in the assessment of inflammatory activity of rheumatoid arthritis patients in remission

BACKGROUND

Soluble urokinase plasminogen activator receptor (suPAR) is a biomarker increasingly used for the assessment of systemic inflammation. We aimed to evaluate suPAR for the assessment of inflammatory activity in rheumatoid arthritis (RA) patients in remission.

METHODS

In our cross-sectional study we measured plasma suPAR and C-reactive protein (CRP) levels as well as erythrocyte sedimentation rate (ESR) in 120 RA patients at various stages of disease activity and 29 healthy age-matched controls.

RESULTS

suPAR, CRP and ESR values were higher in RA patients compared to healthy individuals. When suPAR levels were analyzed according to DAS28 scores of RA patients, suPAR level in the subgroup with DAS28≤2.6 was lower than in the subgroup with DAS28>2.6, but still higher than in controls [4.45 (3.33-5.56) ng/mL vs. 3.66 (3.10-4.67) ng/mL vs. 2.80 (2.06-3.42) ng/mL, p<0.0001, median (interquartile range)]. In contrast, CRP and ESR values were comparable in the subgroup with DAS28≤2.6 and in healthy individuals. We further analyzed the correlation between the number of tender and/or swollen joints and suPAR levels in RA patients in remission. suPAR values were significantly higher in patients with four tender and/or swollen joints than in patients with 2-3 or 0-1 tender and/or swollen joints.

CONCLUSIONS

While CRP and ESR values indicate remission of the chronic inflammatory process in RA, suPAR values are still elevated compared to healthy individuals. suPAR might be particularly valuable in the recognition of inflammatory activity in patients who are in remission according to DAS28 scores but have symptoms of tender and/or swollen joints.

Corneal Langerhans cell and dry eye examinations in ankylosing spondylitis

APCs of the ocular surface, including corneal Langerhans cells (LCs), offer the opportunity to gain insight into the activity of innate immunity. We examined corneal LCs and dry eye parameters in ankylosing spondylitis (AS). Twenty-four AS patients with varying degrees of disease activity and 24 healthy participants were enrolled. Central and peripheral LC numbers, and Langerhans cell morphology (LCM) were assessed with in vivo laser confocal microscopy. In addition, ocular surface disease index, lid parallel conjunctival folds, tear break up time, and Schirmer test were evaluated. LC densities and central LCM were greater in AS patients than in the controls. Moreover, LCM was significantly greater in patients with higher systemic inflammation according to elevated C-reactive protein (CRP). Also, tear production was greatly suppressed in patients with more severe onset of the systemic inflammation according to the Bath Ankylosing Spondylitis Disease Activity Index and elevated CRP. Greater corneal LC density and LCM in AS may reflect an increased activation state of the innate immune system of the cornea in AS, which correlates with the systemic activity of AS even without ocular symptoms. Nonetheless, higher systemic inflammation might impair tear production, and it might partly explain the dry eye mechanism.

Predation drives stable coexistence ratios between red and green pea aphid morphs

We conducted field surveys and experiments to evaluate the hypothesis that predation is an important driving factor determining the degree of coexistence between red and green morphs of the pea aphid Acyrthosiphon pisum. Theory suggests that the different colour morphs are differentially susceptible to natural enemies and selection by predation which in turn leads to variable relative abundances of red and green morphs among host plants across landscapes. Our field surveys on pea and alfalfa revealed, however, that the colour morphs tended to coexist closely in a ratio of one red to three green aphids across fields with different host plant monocultures. Experimentation involving manipulation of the relative abundances of the two colour morphs on host plants pea and alfalfa with and without predator presence revealed that red morphs had higher or same fitness (per capita reproduction) than green morphs on both pea and alfalfa only when in the proportion of one red/three green proportion. Moreover, experimentation evaluating predator efficiency revealed that red morphs are safest from predation when in a 1 : 3 ratio with green morphs. These results suggest that in addition to predation selection effects, red morphs may behaviourally choose to associate with green morphs in a narrow 1 : 3 ratio to maximize their fitness. This evidence, along with existing published data on red and green morph anti-predator behaviour indicates that a 1 : 3 red and green morph coexistence ratio is driven by a balance between predation pressure and behavioural assorting by red morphs across landscapes. In this way predators may have ecological-evolutionary consequences for traits that affect the colour morphs' proportion and tolerances to selective pressure.

Neuroimmune interactions in Sjögren's syndrome: relationship of exocrine gland dysfunction with autoantibodies to muscarinic acetylcholine receptor-3 and mental health status parameters

OBJECTIVES

Antimuscarinic acetylcholine receptor-3 (m3AChR) autoantibodies have been described in primary Sjögren's syndrome (pSS). The aim of this study was to compare various methods for their detection and to assess the contributions of anti-m3AChR and other immunological and psychosocial factors to the pathomechanism of secondary SS (sSS).

METHODS

Sixty-five rheumatoid arthritis (RA) patients, 103 systemic lupus erythematosus (SLE) patients, 76 pSS patients and 50 controls were compared. Three immunodominant epitopes of m3AChR were synthesized and used in ELISA. Two extracellular epitopes were also prepared in fusion with glutathione-S-transferase and one in conjugation with bovine serum albumin. Mental health status was assessed with the 36-item Short-Form Health Survey and Functional Assessment of Chronic Illness Therapy fatigue scale. Correlations were evaluated between glandular function and anti-m3AChR positivities and specificities, features of SLE and RA, and mental health parameters.

RESULTS

Fourteen RA and 27 SLE patients had sSS. The autoantibody levels to all epitopes of m3AChR were significantly higher in pSS and SLE patients than in the controls. The fusion protein forms discriminated RA from pSS and SLE; furthermore, the YNIP fusion protein also distinguished pSS from SLE. The prevalence and the mean levels of all autoantibodies did not differ statistically between sicca and non-sicca SLE or RA patients. Glandular dysfunction correlated with higher age in SLE and RA and an impaired health-related quality of life in SLE.

CONCLUSIONS

The second and third extracellular loops of m3AChR are antigenic in pSS. Immunoassays with antigens as fusion peptides demonstrate the best performance. Sicca SLE patients have worse mental health status. Anti-m3AChR antibodies represent a peculiar example of neuroimmune interactions.

In vivo confocal microscopic evaluation of corneal Langerhans cell density, and distribution and evaluation of dry eye in rheumatoid arthritis

Corneal Langerhans cells (LCs) offer the opportunity to gain insight into the activity of the innate immunity. We examined the density and the distribution of LCs and compared the results with dry-eye parameters in rheumatoid arthritis (RA). Fifty-two RA patients with various degrees of disease activity and 24 healthy subjects were enrolled. Peripheral and central LC number and morphology were assessed with in vivo laser confocal microscopy. In addition, ocular surface disease index (OSDI), lid parallel conjunctival folds, Schirmer test, and tear break-up time (TBUT) were evaluated. The prevalence of central and peripheral LC, and the central LC morphology values (LCM) were higher than normal in RA. Within the RA group, LC prevalence and morphology were not affected by disease activity. However, patients on anti-TNF or glucocorticosteroid (GCS) therapy exhibited normal LCM, and normal central and peripheral LC density. OSDI was higher and TBUT was lower than normal in RA. The alteration of LC in RA suggests an active inflammatory process in the cornea, which may reflect an increased activation state of the innate immune system-even in inactive stages of RA and without ocular symptoms. The results also indicate ocular effects of GCS therapy in RA.