The abnormal signaling of the B cell receptor and co-receptors of lupus B cells.

It is easily understood that studying the physiology and pathophysiology of the BCRtriggered cascade is of importance, particularly in such diseases as systemic lupus erythematosus (SLE) that are considered by many as a "B cell disease". Even though B cells are not considered as the only players in lupus pathogenesis, and other immune and non-immune cells are certainly involved, it is the success of recent B cell-targeting treatment strategies that ascribe a critical role to the lupus B cell.

Apremilast for biologic-naïve, peripheral psoriatic arthritis, including patients with early disease: results from the APROACH observational prospective study.

To evaluate the effect of the phosphodiesterase 4 inhibitor apremilast in biologic-naïve patients with early peripheral PsA in terms of disease activity, clinical manifestations, patient-perceived outcomes, as well as apremilast's safety profile in routine care settings of Greece. Non-interventional, multicenter, 52-week prospective cohort study, enrolling biologic-naïve patients with early active peripheral PsA who started apremilast after intolerance or inadequate response (within the first 12 months of treatment) to an initial conventional synthetic (cs)DMARD treatment. Non-responder imputation was applied for missing data.In total, 167 consecutive patients (mean age: 52.5 years; median PsA duration: 0.9 years) were analyzed. At baseline, the median (interquartile range) clinical Disease Activity in Psoriatic Arthritis (cDAPSA) score was 22.0 (16.0-29.0), with 86.8% of patients having at least moderate (29.3% high) disease activity; 87.4% had skin psoriasis, 37.7% nail psoriasis, 30.7% enthesitis, and 12.4% dactylitis. At 16, 24, and 52 weeks, 28.7, 42.5, and 48.5% of patients, achieved ≥ 50% improvement in their baseline cDAPSA score, respectively. At week 52, 55.6, 50, and 26.8% of evaluable patients achieved complete resolution of enthesitis, dactylitis and nail psoriasis, respectively. Improvements were also observed in patient's health state assessed by the Psoriatic Arthritis Impact of Disease 12-item questionnaire, and health-related quality of life. The 52-week drug survival rate was 75%, while 13.8% of patients experienced at least one adverse drug reaction.Biologic-naïve patients with early PsA, treated with apremilast experienced significant improvements in disease activity, extra-articular manifestations and patient-centered outcomes, accompanied by a favorable tolerability profile.

Better outcomes of COVID-19 in vaccinated compared to unvaccinated patients with systemic rheumatic diseases.

OBJECTIVE: Τo report outcomes of breakthrough COVID-19 in comparison with COVID-19 in unvaccinated patients with systemic rheumatic diseases (SRDs). METHODS: Patients with SRD with COVID-19 (vaccinated and unvaccinated) were included by their rheumatologists in a registry operated by the Greek Rheumatology Society in a voluntarily basis. Type, date and doses of SARS-CoV-2 vaccines were recorded, and demographics, type of SRD, concurrent treatment, comorbidities and COVID-19 outcomes (hospitalisation, need for oxygen supplementation and death) were compared between vaccinated and unvaccinated patients. RESULTS: Between 1 March 2020 and 31 August 2021, 195 patients with SRD with COVID-19 were included; 147 unvaccinated and 48 vaccinated with at least one dose of a SARS-CoV-2 vaccine (Pfizer n=38 or AstraZeneca n=10). Among vaccinated patients, 29 developed breakthrough COVID-19 >14 days after the second vaccine dose (fully vaccinated), while 19 between the first and <14 days after the second vaccine dose (partially vaccinated). Despite no differences in demographics, SRD type, treatment or comorbidities between unvaccinated and vaccinated patients, hospitalisation and mortality rates were higher in unvaccinated (29.3% and 4.1%, respectively) compared with partially vaccinated (21% and 0%) or fully vaccinated (10.3% and 0%) patients. CONCLUSIONS: Vaccinated patients with SRD with breakthrough COVID-19 have better outcomes compared with unvaccinated counterparts with similar disease/treatment characteristics.

Man-in-a-barrel syndrome: a rare presentation of giant cell arteritis.

We present herein the case of a patient with brachial plexopathy, the first manifestation of giant cell arteritis (GCA). A 71-year-old woman presented with a subacute-onset weakness of her upper extremities; the patient had an initially good clinical response to steroid treatment. However, a few weeks after steroid discontinuation, she manifested fever and fatigue and increased serum markers consistent with a systemic inflammatory response. A PET-CT scan revealed an increased uptake in the subclavian arteries and a temporal biopsy was typical for GCA. Oral administration of high dosage steroids improved the patient's clinical symptoms and normalised her inflammatory serum markers.

B cell depletion treatment decreases Th17 cells in patients with rheumatoid arthritis.

INTRODUCTION: We aimed to evaluate for any possible effects of treatment with rituximab (RTX) on the peripheral Th17 and Treg subpopulations in patients with rheumatoid arthritis (RA). PATIENTS AND METHODS: We analyzed 16 patients with RA initiating RTX treatment, 11 patients with RA initiating abatacept treatment, 11 patients with RA treated with other medications, 8 patients with other autoimmune rheumatic diseases initiating RTX, and 14 healthy volunteers. Th17 cells (CD4+IL23R+IL17A+) and Treg cells (CD4+CD25hiFoxP3+) were evaluated flow-cytometrically. RESULTS: Th17 cells from patients treated with RTX decreased significantly at weeks 8 and 16 (mean ± SEΜ: 3.01% ± 0.54℅ CD4+ cells at week 0 vs. 1.53% ± 0.24℅ at week 8 vs 1.10% ± 0.20℅ at week 16, p = 0.0004). Reductions of Th17 cells were evident in clinical responders (DAS28 score ≤ 3.2), ACPA (+) and RF (-) patients; circulating Tregs remained stable. Th17 and Tregs were not affected by ABA treatment or by changes in disease activity. Tregs, but not Th17 cells, decreased following treatment with RTX in patients with other autoimmune diseases (0.75% ± 0.16% at week 0 vs. 0.43% ± 0.16% at week 8, p = 0.033). CONCLUSION: RTX-induced B cell depletion results in a significant reduction of circulating Th17 cell percentages, whereas it has no effect on Tregs of patients with RA. This reduction of Th17 cells was evident particularly in responders to RTX treatment, ACPA+ and RF (-) patients with RA.

A prospective multicenter study assessing humoral immunogenicity and safety of the mRNA SARS-CoV-2 vaccines in Greek patients with systemic autoimmune and autoinflammatory rheumatic diseases.

OBJECTIVES: To investigate humoral responses and safety of mRNA SARS-CoV-2 vaccines in systemic autoimmune and autoinflammatory rheumatic disease (SAARD) patients subjected or not to treatment modifications during vaccination. METHODS: A nationwide, multicenter study, including 605 SAARD patients and 116 controls, prospectively evaluated serum anti-SARS-CoV-2 S1-protein IgG antibody titers, side-effects, and disease activity, one month after complete vaccination, in terms of distinct treatment modification strategies (none, partial and extended modifications). Independent risk factors associated with hampered humoral responses were identified by data-driven multivariable logistic regression analysis. RESULTS: Patients with extended treatment modifications responded to vaccines similarly to controls as well as SAARD patients without immunosuppressive therapy (97.56% vs 100%, p = 0.2468 and 97.56% vs 97.46%, p > 0.9999, respectively). In contrast, patients with partial or without therapeutic modifications responded in 87.50% and 84.50%, respectively. Furthermore, SAARD patients with extended treatment modifications developed higher anti-SARS-CoV-2 antibody levels compared to those without or with partial modifications (median:7.90 vs 7.06 vs 7.1, p = 0.0003 and p = 0.0195, respectively). Mycophenolate mofetil (MMF), rituximab (RTX) and methotrexate (MTX) negatively affected anti-SARS-CoV-2 humoral responses. In 10.5% of vaccinated patients, mild clinical deterioration was noted; however, no differences in the incidence of deterioration were observed among the distinct treatment modification SAARD subgroups. Side-effects were generally comparable between SAARD patients and controls. CONCLUSIONS: In SAARD patients, mRNA SARS-CoV-2 vaccines are effective and safe, both in terms of side-effects and disease flares. Treatment with MMF, RTX and/or MTX compromises anti-SARS-CoV-2 antibody responses, which are restored upon extended treatment modifications without affecting disease activity.

An MRI study of immune checkpoint inhibitor-induced musculoskeletal manifestations myofasciitis is the prominent imaging finding.

OBJECTIVE: To assess: (i) the prevalence, and clinical and imaging characteristics of immune checkpoint inhibitor (ICI)-induced musculoskeletal immune-related adverse events (ir-AEs) in a prospective manner and (ii) whether serum levels of cytokines associated with the Th1/Th2/Th17 response are differentially expressed in patients with and without musculoskeletal Ir-AEs. METHODS: All patients treated with ICI who developed musculoskeletal manifestations were referred to the Rheumatology Department, and an MRI of the involved area(s) was performed. RESULTS: During the study period, a total of 130 patients were treated with ICIs. Of these, 10 (7.7%) developed ICI-induced Ir-AEs. The median time from ICI treatment since development of symptoms was 2.5 months. Three different patterns of musculoskeletal manifestations were found: (i) prominent joint involvement (n = 3); (ii) prominent 'periarticular' involvement (n = 4). These patients had diffuse swelling of the hands, feet or knees. MRI depicted mild synovitis with more prominent myositis and/or fasciitis in the surrounding tissues in all cases; (iii) myofasciitis (n = 3). Clinically, these patients presented with pain in the knee(s)/thigh(s), whereas MRI depicted myofasciitis of the surrounding muscles. Patients with musculoskeletal ir-AEs had significantly higher oncologic response rates compared with patients not exhibiting musculoskeletal ir-AEs (50% vs 12.5%, respectively, P = 0.0016). Cytokine levels associated with a Th1/Th2/Th17 response were similar between patients with and without musculoskeletal ir-AEs. Overall, symptoms were mild/moderate and responded well to treatment, with no need for ICI discontinuation. CONCLUSION: In our cohort, ICI-induced musculoskeletal manifestations developed in 7.7% of patients. Imaging evidence of myofasciitis was found in most patients, indicating that the muscle/fascia is more frequently involved than the synovium.

B cell depletion treatment decreases CD4+IL4+ and CD4+CD40L+ T cells in patients with systemic sclerosis.

Recent data suggests that rituximab may favorably affect skin fibrosis and lung function in patients with systemic sclerosis. Based on experimental data suggesting a key role of B and T cells in scleroderma we aimed to explore the effect(s) of rituximab treatment on T cell subpopulations. Fifteen patients with scleroderma who received rituximab treatment and six who received standard treatment alone were recruited. Peripheral CD4+IL4+, CD4+INFγ+, CD4+IL17+ and CD4+CD40L+ T cells were assessed using flow cytometry. Using ELISA, serum levels of IL4 were assessed. Skin CD4+IL4+ T cells were assessed with confocal microscopy from skin biopsies. Following rituximab treatment skin CD4+IL4+ T cells obviously decreased as seen with confocal microscopy. Moreover, peripheral CD4+IL4+ T cells decreased significantly compared to those from patients who received standard treatment alone: median (IQR): 14.9 (22.63-12.88) vs 7.87 (12.81-4.9)%, p = 0.005 and 9.43 (19.53-7.50)% vs 14.86 (21.96-6.75)%, p = NS at baseline and 6 months later respectively, whereas there was no difference in serum IL4 levels. Peripheral CD4+CD40L+ T cells also decreased significantly following rituximab treatment compared to those from patients who received standard treatment alone: median (IQR): 17.78 (25.64-14.44)% vs 8.15 (22.85-3.08)%, p = 0.04 and 22.13 (58.77-8.20)% vs 72.11 (73.05-20.45)%, p = NS at baseline and 6 months later respectively. Furthermore, peripheral CD4+INFγ+ and CD4+IL17+ T cells revealed no differences following rituximab treatment. Our study demonstrates a link between rituximab treatment and CD4+IL4+ T cell decrease both in the skin and peripheral blood of patients with SSc.

Th1/17 cells, a subset of Th17 cells, are expanded in patients with active systemic lupus erythematosus.

Skewed cytokine production characterizes T cells in Systemic Lupus Erythematosus (SLE). Among Th17 cells that are expanded in lupus, a subset (Th1/17) retains the ability to produce IFNγ. We aimed to analyze Th17 and Th1/17 cells in patients with SLE. Patients with active disease displayed increased percentages of circulating Τh17 and Th1/17 cells. Stimulated T cells from patients with lupus secreted significantly more IL-17 compared to healthy donors. Also, T cells from patients with active SLE released significantly lower levels of IFN-γ compared to controls. However, following stimulation, levels of IFN-γ also rose significantly. Our data suggest that lupus Th1/17 cells are not only expanded but also functional. In summary, in this study it was shown that patients with active SLE display increased Th17 and functional Th1/17 cells. This impaired T-cell axis might represent a possible future therapeutic target.

Dickkopf-1 is downregulated early and universally in the skin of patients with systemic sclerosis despite normal circulating levels.

OBJECTIVES: The activity of the Wnt pathway, a critical mediator of fibrosis, is regulated by Dickkopf-1 (Dkk-1). Dkk-1 is absent from scleroderma skin in contrast to skin from healthy subjects where it is clearly expressed. There are no data on circulating levels and function of Dkk-1 in patients with systemic sclerosis (SSc). Our objectives are to assess: i) circulating and functional levels of Dkk-1 in patients with SSc and ii) whether the striking lack of Dkk-1 skin expression is also evident in a) clinically uninvolved skin from patients with SSc and b) very early disease prior to skin thickening. METHODS: Circulating Dkk-1 levels were measured in 50 patients with SSc and 50 controls. Skin biopsies were obtained from SSc patients from a) clinically involved skin b) clinically uninvolved skin, c) oedematous skin prior to skin thickening. RESULTS: Circulating and functional Dkk-1 levels were similar in patients with SSc and controls. Healthy skin displayed a high Dkk-1 immuno-expression in the epidermis and dermal fibroblasts in contrast to clinically involved scleroderma skin where Dkk-1 was totally absent. In all biopsies of clinically uninvolved skin Dkk-1 was only moderately expressed whereas skin from very early disease displayed only a weak Dkk-1 immunoreactivity. CONCLUSIONS: The downregulation of Dkk-1 at the oedematous phase of the disease indicates that the Wnt pathway is involved early in the disease process and may play a role in driving fibrosis. The decrease in Dkk-1 expression in clinically uninvolved scleroderma skin indicates that skin in SSc is universally affected.

Intestinal Involvement in Systemic Sclerosis: A Clinical Review.

Systemic sclerosis (SSc) is a chronic systemic disease characterized by microvasculopathy, autoantibodies, and extensive fibrosis. Intestinal involvement is frequent in SSc and represents a significant cause of morbidity. The pathogenesis of intestinal involvement includes vascular damage, nerve dysfunction, smooth muscle atrophy, and fibrosis, causing hypomotility, which leads to small intestinal bacterial overgrowth (SIBO), malabsorption, malnutrition, diarrhea, pseudo-obstruction, constipation, pneumatosis intestinalis, and fecal incontinence. Manifestations are often troublesome and reduce quality of life and life expectancy. Assessment of intestinal involvement includes screening for small intestine hypomotility, malnutrition, SIBO, and anorectal dysfunction. Current management of intestinal manifestations is largely inadequate. Patients with diarrhea are managed with low-fat diet, medium-chain triglycerides, avoidance of lactulose and fructose, and control of bacterial overgrowth with antibiotics for SIBO. In diarrhea/malabsorption, bile acid sequestrant and pancreatic enzyme supplementation may help, and nutritional support is needed. General measures are applied for constipation, and intestine rest plus antibiotics for pseudo-obstruction. Fecal incontinence is managed with measures for associated SIBO, or constipation, and with behavioral therapies. Pneumatosis intestinalis is usually an incidental finding that does not require any specific treatment. Immunomoduation should be considered early in intestinal involvement. Multidisciplinary approach of intestinal manifestations in SSc by gastroenterologists and rheumatologists is required for optimum management.

Decreased CD22 expression and intracellular signaling aberrations in B cells of patients with systemic sclerosis.

The objective of the study was to explore the phenotype and intracellular signaling events of B cells in patients with systemic sclerosis (SSc). Peripheral blood B cell surface markers CD19 and CD22 were evaluated by flow cytometry in 23 patients with SSc and seven healthy individuals. Levels of intracellular kinases Lyn, Syk and P-Y 348 Syk along with phosphatase SHP-1 were examined with Western immunoblotting in selected patients. P-Y 822 CD22 was subsequently evaluated flow cytometrically in antigen receptor stimulated B cells. A statistically significant decrease in CD22 B cell surface expression was found in the diffuse subset of patients (median CD22 MFI ± SD was 5.90 ± 2.35 vs 10.20 ± 1.88 for patients vs healthy controls respectively; p = 0.021), while no statistically significant change was found regarding CD19. CD22 underexpression was more pronounced when interstitial lung disease (ILD) was present (median CD22 MFI ± SD was 5.90 ± 2.25 vs 10.20 ± 1.88 for patients with ILD vs healthy controls respectively; p = 0.011). CD22 phosphorylation following B cell receptor (BCR) stimulation was also found to be impaired in patients with diffuse SSc (median change in MFI ± SD was 0.28 ± 0.09 vs 0.38 ± 0.08 for patients vs healthy controls respectively; p = 0.034). Low CD22 expression was arithmetically correlated with kinase Lyn underexpression (Pearson coefficient 0.926; p = ns) in B cells from a small sample of patients. These results suggest that CD22 underexpression and impaired phosphorylation along with implications for Lyn kinase aberrations could contribute to the activated B cell phenotype in SSc.

B Cell-Based Treatments in SLE: Past Experience and Current Directions.

PURPOSE OF REVIEW: B cells have been targeted recently by novel therapeutic approaches in patients with SLE. In this review, we discuss recent data that have emerged on this issue placing special emphasis in studies published during the last 5 years. RECENT FINDINGS: Despite the negative results stemming from double-blind placebo-controlled studies, B cell depletion with rituximab is indeed employed worldwide, particularly in standard treatment refractory lupus, with promising results. In addition, positive experience with the approved agent belimumab is steadily increasing. Both regimens have an acceptable safety profile. Identification of B cells as a therapeutic target in SLE has been so far rewarding, since one such treatment, belimumab, has been the only regulatory authority-approved medication in SLE for over half a century. Focusing specifically on autoreactive instead of non-specifically altering/depleting lupus, B cells may lead to more rational treatment modes.

Roles of the protein tyrosine phosphatase PTPN22 in immunity and autoimmunity.

PTPN22 is a protein tyrosine phosphatase expressed by the majority of cells belonging to the innate and adaptive immune systems. Polymorphisms in PTPN22 are associated with several autoimmune diseases, such as systemic lupus erythematosus, rheumatoid arthritis and type 1 diabetes. This review discusses the role of PTPN22 in T and B cells, and its function in innate immune cells, such as monocytes, dendritic cells and NK cells. We focus particularly on the complexity that underlies the function of PTPN22 in the biological processes of the immune system; such complexity has led various research groups to produce rather conflicting data.

Omicron variant dominance and anti-SARS-CoV-2 vaccination are key determinants for a milder course of COVID-19 in patients with systemic autoimmune rheumatic diseases.

INTRODUCTION: This study aimed to determine whether the introduction of anti-SARS-CoV-2 vaccines and the dominance of the omicron variant had a significant impact on the outcome of COVID-19 in patients with systemic autoimmune rheumatic diseases (SAIRDs). METHODS: Using data entered to the Greek Rheumatology Society COVID-19 registry, we investigated the incidence of hospitalization and death due to COVID-19, during the successive periods of the pandemic according to the prevalent strain (wild-type, Alpha, Delta, Omicron) in vaccinated and unvaccinated patients. Variables independently associated with hospitalization and death were explored using multivariate regression analyses, while Kaplan-Meier curves were used to depict survival data. RESULTS: From August 2020 until June 30, 2022, 456 cases (70.2% females) of COVID-19 with a mean age (± SD) of 51.4 ± 14.0 years were reported. In unvaccinated patients, the proportions of hospitalization and death were 24.5% and 4%, compared to 12.5% and 0.8% in the vaccinated group (p < 0.001 for both comparisons). The rates of hospitalization for the wild-type, Alpha, Delta, and Omicron periods were 24.7%, 31.3%, 25.9%, and 8.1% respectively (p < 0.0001), while the case fatality rates were 2.7%, 4%, 7%, and 0%, respectively (p = 0.001). Using multivariable regression analysis, factors independently associated with hospitalization were infection by a non-Omicron variant, being non-vaccinated, exposure to rituximab, older age, and respiratory and cardiovascular disease. Independent predictors for death were contracting COVID-19 during the Alpha or Delta period, pulmonary disease, and older age, while being vaccinated was protective. CONCLUSIONS: In this 2-year analysis, the rates of hospitalization and death among patients with SAIRDs have declined significantly. Vaccination and the dominance of the Omicron variant appear to be the major determinants for this shift. Key points • During the late phase of the pandemic, the proportion of severe COVID-19 cases, defined as requiring hospitalization or resulting in death, in patients with systemic autoimmune rheumatic diseases has declined. • Anti-SARS-CoV-2 vaccination and the dominance of the Omicron strain are the key factors that have independently contributed to this shift.

Effect of long-term treatment with rituximab on pulmonary function and skin fibrosis in patients with diffuse systemic sclerosis.

OBJECTIVES: To assess the safety and efficacy of long-term treatment with rituximab (RTX) in patients with systemic sclerosis (SSc). METHODS: Eight patients with SSc-associated interstitial lung disease (ILD) received 4 cycles of RTX and had a follow-up of 2 years. Lung involvement was assessed by pulmonary function tests and chest HRCT. Skin involvement was assessed both clinically and histologically. RESULTS: We found a linear improvement of lung function and skin thickening over the 2 years of RTX treatment. There was a significant increase of FVC at 2 years compared to baseline (mean ± SEM: 77.13±7.13 vs. 68.13±6.96, respectively, p<0.0001). Similarly, DLco increased significantly at 2 years compared to baseline (mean ± SEM: 63.13±7.65 vs. 52.25±7.32, respectively, p<0.001). Skin thickening, assessed with the MRSS, improved significantly at 2 years compared to baseline (mean ± SEM: 4.87±0.83 vs. 13.5±2.42, respectively, p<0.0001). A reduction in myofibroblast score was seen histologically following RTX treatment. CONCLUSIONS: Our results indicate that long-term treatment with RTX may favourably affect lung function and skin fibrosis in patients with SSc. Larger scale, multicentre, randomised, controlled studies are needed to further explore the efficacy of RTX in SSc.