CXCR4: from B-cell development to B cell-mediated diseases

Chemokine receptors are members of the G protein-coupled receptor superfamily. The C-X-C chemokine receptor type 4 (CXCR4), one of the most studied chemokine receptors, is widely expressed in hematopoietic and immune cell populations. It is involved in leukocyte trafficking in lymphoid organs and inflammatory sites through its interaction with its natural ligand CXCL12. CXCR4 assumes a pivotal role in B-cell development, ranging from early progenitors to the differentiation of antibody-secreting cells. This review emphasizes the significance of CXCR4 across the various stages of B-cell development, including central tolerance, and delves into the association between CXCR4 and B cell-mediated disorders, from immunodeficiencies such as WHIM (warts, hypogammaglobulinemia, infections, and myelokathexis) syndrome to autoimmune diseases such as systemic lupus erythematosus. The potential of CXCR4 as a therapeutic target is discussed, especially through the identification of novel molecules capable of modulating specific pockets of the CXCR4 molecule. These insights provide a basis for innovative therapeutic approaches in the field.

An immunogenomic exome landscape of triple positive primary antiphospholipid patients

Primary antiphospholipid syndrome is characterized by thrombosis and autoantibodies directed against phospholipids or associated proteins. The genetic etiology of PAPS remains unknown. We enrolled 21 patients with thromboembolic events associated to lupus anticoagulant, anticardiolipin and anti β2 glycoprotein1 autoantibodies. We performed whole exome sequencing and a systematic variant-based analysis in genes associated with thrombosis, in candidate genes previously associated with APS or inborn errors of immunity. Data were compared to public databases and to a control cohort of 873 non-autoimmune patients. Variants were identified following a state-of-the-art pipeline. Enrichment analysis was performed by comparing with the control cohort. We found an absence of significant HLA bias and genetic heterogeneity in these patients, including when testing combinations of rare variants in genes encoding for proteins involved in thrombosis and of variants in genes linked with inborn errors of immunity. These results provide evidence of genetic heterogeneity in PAPS, even in a homogenous series of triple positive patients. At the individual scale, a combination of variants may participate to the breakdown of B cell tolerance and to the vessel damage.

CD19 CAR T-Cell Therapy in Autoimmune Disease - A Case Series with Follow-up

BACKGROUND

Treatment for autoimmune diseases such as systemic lupus erythematosus (SLE), idiopathic inflammatory myositis, and systemic sclerosis often involves long-term immune suppression. Resetting aberrant autoimmunity in these diseases through deep depletion of B cells is a potential strategy for achieving sustained drug-free remission.

METHODS

We evaluated 15 patients with severe SLE (8 patients), idiopathic inflammatory myositis (3 patients), or systemic sclerosis (4 patients) who received a single infusion of CD19 chimeric antigen receptor (CAR) T cells after preconditioning with fludarabine and cyclophosphamide. Efficacy up to 2 years after CAR T-cell infusion was assessed by means of Definition of Remission in SLE (DORIS) remission criteria, American College of Rheumatology-European League against Rheumatism (ACR-EULAR) major clinical response, and the score on the European Scleroderma Trials and Research Group (EUSTAR) activity index (with higher scores indicating greater disease activity), among others. Safety variables, including cytokine release syndrome and infections, were recorded.

RESULTS

The median follow-up was 15 months (range, 4 to 29). The mean (±SD) duration of B-cell aplasia was 112±47 days. All the patients with SLE had DORIS remission, all the patients with idiopathic inflammatory myositis had an ACR-EULAR major clinical response, and all the patients with systemic sclerosis had a decrease in the score on the EUSTAR activity index. Immunosuppressive therapy was completely stopped in all the patients. Grade 1 cytokine release syndrome occurred in 10 patients. One patient each had grade 2 cytokine release syndrome, grade 1 immune effector cell-associated neurotoxicity syndrome, and pneumonia that resulted in hospitalization.

CONCLUSIONS

In this case series, CD19 CAR T-cell transfer appeared to be feasible, safe, and efficacious in three different autoimmune diseases, providing rationale for further controlled clinical trials. (Funded by Deutsche Forschungsgemeinschaft and others.).

Drug upgrade: A complete methodology from old drug to new chemical entities using Nematic Protein Organization Technique

Drug repurposing is used to propose new therapeutic perspectives. Here, we introduce "Drug Upgrade", that is, characterizing the mode of action of an old drug to generate new chemical entities and new therapeutics. We proposed a novel methodology covering target identification to pharmacology validation. As an old drug, we chose hydroxychloroquine (HCQ) for its well-documented clinical efficacy in lupus and its side effect, retinal toxicity. Using the Nematic Protein Organization Technique (NPOT®) followed by liquid chromatography-tandem mass spectrometry analyses, we identified myeloperoxidase (MPO) and alpha-crystallin β chain (CRYAB) as primary and secondary targets to HCQ from lupus patients' peripheral blood mononuclear cells (PBMCs) and isolated human retinas. Surface plasmon resonance (SPR) and enzymatic assays confirmed the interaction of HCQ with MPO and CRYAB. We synthesized INS-072 a novel analog of HCQ that increased affinity for MPO and decreased binding to CRYAB compared to HCQ. INS-072 delayed cutaneous eruption significantly compared to HCQ in the murine MRL/lpr model of spontaneous lupus and prevents immune complex vasculitis in mice. In addition, long-term HCQ treatment caused retinal toxicity in mice, unlike INS-072. Our study illustrates a method of drug development, where new applications or improvements can be explored by fully characterizing the drug's mode of action.

Loss of function of XBP1 splicing activity of IRE1α favors B cell tolerance breakdown

Anti-nuclear antibodies are the hallmark of autoimmune diseases such as systemic lupus erythematosus (SLE) and scleroderma. However, the molecular mechanisms of B cell tolerance breakdown in these pathological contexts are poorly known. The study of rare familial forms of autoimmune diseases could therefore help to better describe common biological mechanisms leading to B cell tolerance breakdown. By Whole-Exome Sequencing, we identified a new heterozygous mutation (p.R594C) in ERN1 gene, encoding IRE1α (Inositol-Requiring Enzyme 1α), in a multiplex family with several members presenting autoantibody-mediated autoimmunity. Using human cell lines and a knock-in (KI) transgenic mouse model, we showed that this mutation led to a profound defect of IRE1α ribonuclease activity on X-Box Binding Protein 1 (XBP1) splicing. The KI mice developed a broad panel of autoantibodies, however in a subclinical manner. These results suggest that a decrease of spliced form of XBP1 (XBP1s) production could contribute to B cell tolerance breakdown and give new insights into the function of IRE1α which are important to consider for the development of IRE1α targeting strategies.

Normal B cells express ZAP70 in chronic lymphocytic leukemia: A link between autoimmunity and lymphoproliferation?

ZAP70 has a prognostic value in chronic lymphocytic leukemia (CLL), through altered B-cell receptor signaling, which is important in CLL pathogenesis. A good correlation between ZAP70 expression in CLL cells and the occurrence of autoimmune phenomena has been reported. Yet, the great majority of CLL-associated autoimmune cytopenia is due to polyclonal immunoglobulin (Ig) G synthesized by nonmalignant B cells, and this phenomenon is poorly understood. Here, we show, using flow cytometry, that a substantial percentage of CD5- nonmalignant B cells from CLL patients expresses ZAP70 compared with CD5- B cells from healthy subjects. This ZAP70 expression in normal B cells from CLL patients was also evidenced by the detection of ZAP70 mRNA at single-cell level with polyclonal Ig heavy- and light-chain gene transcripts. ZAP70+ normal B cells belong to various B-cell subsets and their presence in the naïve B-cell subset suggests that ZAP70 expression may occur during early B-cell development in CLL patients and potentially before malignant transformation. The presence of ZAP70+ normal B cells is associated with autoimmune cytopenia in CLL patients in our cohort of patients, and recombinant antibodies produced from these ZAP70+ nonmalignant B cells were frequently autoreactive including anti-platelet reactivity. These results provide a better understanding of the implication of ZAP70 in CLL leukemogenesis and the mechanisms of autoimmune complications of CLL.

Targeting the chemokine receptor CXCR4 with histamine analog to reduce inflammation in juvenile arthritis

Introduction

Among immune cells, activated monocytes play a detrimental role in chronic and viral-induced inflammatory pathologies, particularly in Juvenile Idiopathic Arthritis (JIA), a childhood rheumatoid arthritis (RA) disease. The uncontrolled activation of monocytes and excessive production of inflammatory factors contribute to the damage of bone-cartilage joints. Despite the moderate beneficial effect of current therapies and clinical trials, there is still a need for alternative strategies targeting monocytes to treat RA.

Methods

To explore such an alternative strategy, we investigated the effects of targeting the CXCR4 receptor using the histamine analog clobenpropit (CB). Monocytes were isolated from the blood and synovial fluids of JIA patients to assess CB's impact on their production of key inflammatory cytokines. Additionally, we administered daily intraperitoneal CB treatment to arthritic mice to evaluate its effects on circulating inflammatory cytokine levels, immune cell infiltrates, joints erosion, and bone resorption, as indicators of disease progression.

Results

Our findings demonstrated that CXCR4 targeting with CB significantly inhibited the spontaneous and induced-production of key inflammatory cytokines by monocytes isolated from JIA patients. Furthermore, CB treatment in a mouse model of collagen-induce arthritis resulted in a significant decrease in circulating inflammatory cytokine levels, immune cell infiltrates, joints erosion, and bone resorption, leading to a reduction in disease progression.

Discussion

In conclusion, targeting CXCR4 with the small amino compound CB shows promise as a therapeutic option for chronic and viral-induced inflammatory diseases, including RA. CB effectively regulated inflammatory cytokine production of monocytes, presenting a potential targeted approach with potential advantages over current therapies. These results warrant further research and clinical trials to explore the full therapeutic potential of targeting CXCR4 with CB-like molecules in the management of various inflammatory diseases.

The efficacy and safety of systemic corticosteroids as first line treatment for granulomatous lymphocytic interstitial lung disease

BACKGROUND

Granulomatous and lymphocytic interstitial lung disease (gl-ILD) is a major cause of morbidity and mortality among patients with common variable immunodeficiency. Corticosteroids are recommended as first-line treatment for gl-ILD, but evidence for their efficacy is lacking.

OBJECTIVES

This study analyzed the effect of high-dose corticosteroids (≥0.3 mg/kg prednisone equivalent) on gl-ILD, measured by high-resolution computed tomography (HRCT) scans, and pulmonary function test (PFT) results.

METHODS

Patients who had received high-dose corticosteroids but no other immunosuppressive therapy at the time (n = 56) and who underwent repeated HRCT scanning or PFT (n = 39) during the retrospective and/or prospective phase of the Study of Interstitial Lung Disease in Primary Antibody Deficiency (STILPAD) were included in the analysis. Patients without any immunosuppressive treatment were selected as controls (n = 23). HRCT scans were blinded, randomized, and scored using the Hartman score. Differences between the baseline and follow-up HRCT scans and PFT were analyzed.

RESULTS

Treatment with high-dose corticosteroids significantly improved HRCT scores and forced vital capacity. Carbon monoxide diffusion capacity significantly improved in both groups. Of 18 patients, for whom extended follow-up data was available, 13 achieved a long-term, maintenance therapy independent remission. All patients with relapse were retreated with corticosteroids, but only one-fifth of them responded. Two opportunistic infections were found in the corticosteroid treatment group, while overall infection rate was similar between cohorts.

CONCLUSIONS

Induction therapy with high-dose corticosteroids improved HRCT scans and PFT results of patients with gl-ILD and achieved long-term remission in 42% of patients. It was not associated with major side effects. Low-dose maintenance therapy provided no benefit and efficacy was poor in relapsing disease.

NBEAL2 deficiency in humans leads to low CTLA-4 expression in activated conventional T cells

Loss of NBEAL2 function leads to grey platelet syndrome (GPS), a bleeding disorder characterized by macro-thrombocytopenia and α-granule-deficient platelets. A proportion of patients with GPS develop autoimmunity through an unknown mechanism, which might be related to the proteins NBEAL2 interacts with, specifically in immune cells. Here we show a comprehensive interactome of NBEAL2 in primary T cells, based on mass spectrometry identification of altogether 74 protein association partners. These include LRBA, a member of the same BEACH domain family as NBEAL2, recessive mutations of which cause autoimmunity and lymphocytic infiltration through defective CTLA-4 trafficking. Investigating the potential association between NBEAL2 and CTLA-4 signalling suggested by the mass spectrometry results, we confirm by co-immunoprecipitation that CTLA-4 and NBEAL2 interact with each other. Interestingly, NBEAL2 deficiency leads to low CTLA-4 expression in patient-derived effector T cells, while their regulatory T cells appear unaffected. Knocking-down NBEAL2 in healthy primary T cells recapitulates the low CTLA-4 expression observed in the T cells of GPS patients. Our results thus show that NBEAL2 is involved in the regulation of CTLA-4 expression in conventional T cells and provide a rationale for considering CTLA-4-immunoglobulin therapy in patients with GPS and autoimmune disease.

Current Transition Practice for Primary Immunodeficiencies and Autoinflammatory Diseases in Europe: a RITA-ERN Survey

BACKGROUND

Due to the absence of curative treatments for inborn errors of immunity (IEI), children born with IEI require long-term follow-up for disease manifestations and related complications that occur over the lifespan. Effective transition from pediatric to adult services is known to significantly improve adherence to treatment and long-term outcomes. It is currently not known what transition services are available for young people with IEI in Europe.

OBJECTIVE

To understand the prevalence and practice of transition services in Europe for young people with IEI, encompassing both primary immunodeficiencies (PID) and systemic autoinflammatory disorders (AID).

METHODS

A survey was generated by the European Reference Network on immunodeficiency, autoinflammatory, and autoimmune diseases Transition Working Group and electronically circulated, through professional networks, to pediatric centers across Europe looking after children with IEI.

RESULTS

Seventy-six responses were received from 52 centers, in 45 cities across 17 different countries. All services transitioned patients to adult services, mainly to specialist PID or AID centers, typically transferring up to ten patients to adult care each year. The transition process started at a median age of 16-18 years with transfer to the adult center occurring at a median age of 18-20 years. 75% of PID and 68% of AID centers held at least one joint appointment with pediatric and adult services prior to the transfer of care. Approximately 75% of PID and AID services reported having a defined transition process, but few centers reported national disease-specific transition guidelines to refer to.

CONCLUSIONS

Transition services for children with IEI in Europe are available in many countries but lack standardized guidelines to promote best practice.

The course of non-infectious uveitis in pregnancy: a retrospective study of 79 pregnancies

PURPOSE

The study aims to describe the course and management of non-infectious uveitis during pregnancy and postpartum period in European populations.

METHODS

A retrospective observational study in two tertiary centers in France was performed. Pregnant patients during the follow-up of a non-infectious uveitis as well as those with new-onset uveitis were included. The medical records were analyzed with a systematic collection of the characteristics of the uveitis, the treatment and evolution of the uveitis, and the course of the pregnancy including obstetric complications.

RESULTS

Seventy-nine pregnancies in 59 women were included: 48 patients (68 pregnancies) were followed for uveitis and 11 had a new-onset uveitis diagnosis. Most patients had idiopathic uveitis (32.2%) or sarcoid uveitis (27.1%). Among the patients followed for uveitis at the time of conception, there were 18 relapses (26.5%) requiring treatment escalation. Relapses occurred mainly in the two first trimester (n = 12) or during the postpartum period (n = 5) and were significantly associated with an active uveitis at the time of conception (OR = 9.2, 95% CI [1.57-48.4], p = 0.01). The characteristics of the new-onset uveitis were similar to those already existing before pregnancy. Obstetric complications occurred in 25 pregnancies (31.6%), mainly gestational hypertension and gestational diabetes.

CONCLUSION

The frequency of non-infectious uveitis relapses decreases as pregnancy progresses, in agreement with data from other non-European studies. However, multidisciplinary monitoring should be advised, especially to uncontrolled patients at the time of conception.

Tolerance and efficacy of targeted therapies prescribed for off-label indications in refractory systemic autoimmune diseases: data of the first 100 patients enrolled in the TATA registry (TArgeted Therapy in Autoimmune Diseases)

Objectives

To assess the tolerance and efficacy of targeted therapies prescribed off-label in refractory low-prevalence autoimmune and inflammatory systemic diseases.

Methods

The TATA registry (TArgeted Therapy in Autoimmune Diseases) is a prospective, observational, national and independent cohort follow-up. The inclusion criteria in the registry are as follows: age >18 years; low-prevalence autoimmune and inflammatory systemic disease treated with off-label drugs started after 1 January 2019.

Results

Hundred (100) patients (79 women) were enrolled. The median age was 52.5 years (95% CI 49 to 56) and the median disease duration before enrolment was 5 years (3 to 7). The targeted therapies at enrolment were as follows: Janus kinase/signal transducers and activators of transcription inhibitors (44%), anti-interleukin (IL)-6R (22%), anti-IL-12/23, anti-IL-23 and anti-IL-17 (9%), anti-B cell activating factor of the tumour necrosis factor family (5%), abatacept (5%), other targeted treatments (9%) and combination of targeted treatments (6%). 73% of patients were receiving corticosteroid therapy at enrolment (median dose 10 mg/day). The current median follow-up time is 9 months (8 to 10).

Safety: 11 serious infections (incidence rate of 14.8/100 patient-years) and 1 cancer (1.3 cancers/100 patient-years) were observed. Two patients died from severe COVID-19 (2.7 deaths/100 patient-years).

Efficacy: the targeted treatment was considered effective by the clinician in 56% of patients and allowed, in responders, a median reduction of oral corticosteroids of 15 (9 to 21) mg/day, below 7.5 mg/day in 76% of patients, while 28% discontinued.

Conclusion

These initial results of the TATA registry confirm the diversity of targeted treatments prescribed off-label in refractory autoimmune diseases and their corticosteroid-sparing effect when effective. Tolerance was acceptable in these refractory patients with a long history of treatment with immunosuppressive drugs.

Fatigue is independently associated with disease activity assessed using the Physician Global Assessment but not the SLEDAI in patients with systemic lupus erythematosus

OBJECTIVES

To analyse whether reported fatigue, one of the most challenging manifestations of systemic lupus erythematosus (SLE), may bias the assessment of disease activity in SLE according to the Physician Global Assessment (PGA).

METHODS

Patients from the Lupus BioBank of the upper Rhein database, a cross-sectional multicentre collection of detailed clinical and biological data from patients with SLE, were included. Patients had to fulfil the 1997 American College of Rheumatology criteria for SLE and the PGA (0-3 scale) at the time of inclusion had to be available. Fatigue was assessed according to the Fatigue Scale for Motor and Cognitive Functions. Univariate and multivariate regression models were built to determine which variables were associated with the PGA.

RESULTS

A total of 350 patients (89% female; median age: 42 years, IQR: 34-52) were included. The median Safety of Estrogens in Lupus Erythematosus National Assessment-Systemic Lupus Erythematosus Disease Activity Index (SELENA-SLEDAI) score was 4 (IQR: 2-6). Of these 350 patients, 257 (73%) reported significant fatigue. The PGA (p=0.004) but not the SELENA-SLEDAI (p=0.43) was significantly associated with fatigue. Both fatigue and SELENA-SLEDAI were independently associated with the PGA in two different multivariate models.

CONCLUSION

Fatigue is independently associated with disease activity assessed using the PGA but not the SLEDAI. These findings highlight the fact that the PGA should capture only objectively active disease manifestations in order to improve its reliability.

Biochemically deleterious human NFKB1 variants underlie an autosomal dominant form of common variable immunodeficiency

Autosomal dominant (AD) NFKB1 deficiency is thought to be the most common genetic etiology of common variable immunodeficiency (CVID). However, the causal link between NFKB1 variants and CVID has not been demonstrated experimentally and genetically, as there has been insufficient biochemical characterization and enrichment analysis. We show that the cotransfection of NFKB1-deficient HEK293T cells (lacking both p105 and its cleaved form p50) with a κB reporter, NFKB1/p105, and a homodimerization-defective RELA/p65 mutant results in p50:p65 heterodimer–dependent and p65:p65 homodimer–independent transcriptional activation. We found that 59 of the 90 variants in patients with CVID or related conditions were loss of function or hypomorphic. By contrast, 258 of 260 variants in the general population or patients with unrelated conditions were neutral. None of the deleterious variants displayed negative dominance. The enrichment in deleterious NFKB1 variants of patients with CVID was selective and highly significant (P = 2.78 × 10⁻¹⁵). NFKB1 variants disrupting NFKB1/p50 transcriptional activity thus underlie AD CVID by haploinsufficiency, whereas neutral variants in this assay should not be considered causal.

Case Report: Acquired Disseminated BCG in the Context of a Delayed Immune Reconstitution After Hematological Malignancy

Context

Disseminated infections due to Mycobacterium bovis Bacillus Calmette-Guérin (BCG) are unusual and occur mostly in patients with inborn error of immunity (IEI) or acquired immunodeficiency. However, cases of secondary BCGosis due to intravesical BCG instillation have been described. Herein, we present a case of severe BCGosis occurring in an unusual situation.

Case Description

We report one case of severe disseminated BCG disease occurring after hematological malignancy in a 48-year-old man without BCG instillation and previously vaccinated in infancy with no complication. Laboratory investigations demonstrated that he was not affected by any known or candidate gene of IEI or intrinsic cellular defect involving IFNγ pathway. Whole genome sequencing of the BCG strain showed that it was most closely related to the M. bovis BCG Tice strain, suggesting an unexpected relationship between the secondary immunodeficiency of the patient and the acquired BCG infection.

Conclusion

This case highlights the fact that, in addition to the IEI, physicians, as well as microbiologists and pharmacists should be aware of possible acquired disseminated BCG disease in secondary immunocompromised patients treated in centers that administrate BCG for bladder cancers.

Patterns of fatigue and association with disease activity and clinical manifestations in systemic lupus erythematosus

OBJECTIVE

The prevalence of fatigue is high in patients with systemic lupus erythematosus (SLE). In this study, we used latent class analysis to reveal patterns of fatigue, anxiety, depression and organ involvement in a large international cohort of SLE patients.

METHODS

We used the Lupus BioBank of the upper Rhein to analyse patterns of fatigue using latent class analysis (LCA). After determining the optimal number of latent classes, patients were assigned according to model generated probabilities, and characteristics of classes were compared.

RESULTS

A total of 502 patients were included. Significant fatigue, anxiety and depression were reported by 341 (67.9%), 159 (31.7%) and 52 (10.4%) patients, respectively. LCA revealed a first cluster (67.5% of patients) with low disease activity [median (25th-75th percentile interquartile range) Safety of Estrogens in Lupus Erythematosus National Assessment (SELENA)-SLEDAI: 2 (0-4)], significant fatigue (55.5%, P < 0.0001), low anxiety (11.8%, P < 0.0001) and depression (0.9%, P < 0.0001). Cluster 2 (25.3%) also comprised patients with low disease activity [SELENA-SLEDAI: 2 (0-6)], but those patients had a very high prevalence of fatigue (100%, P < 0.0001), anxiety (89%, P < 0.0001) and depression (38.6%, P < 0.0001). Cluster 3 (7.2%) comprised patients with high disease activity [SELENA-SLEDAI: 12 (8-17), P < 0.0001] and high fatigue (72.2%, P < 0.0001) with low levels of anxiety (16.7%, P < 0.0001) and no depression (0%, P < 0.0001).

CONCLUSION

LCA revealed three patterns of fatigue with important practical implications. Based on these, it is crucial to distinguish patients with active disease (in whom remission will be achieved) from those with no or mild activity but high levels of fatigue, depression and anxiety, for whom psychological counselling should be prioritized.

Genetic Analysis of a Cohort of 275 Patients with Hyper-IgE Syndromes and/or Chronic Mucocutaneous Candidiasis

Hyper-IgE syndromes and chronic mucocutaneous candidiasis constitute rare primary immunodeficiency syndromes with an overlapping clinical phenotype. In recent years, a growing number of underlying genetic defects have been identified. To characterize the underlying genetic defects in a large international cohort of 275 patients, of whom 211 had been clinically diagnosed with hyper-IgE syndrome and 64 with chronic mucocutaneous candidiasis, targeted panel sequencing was performed, relying on Agilent HaloPlex and Illumina MiSeq technologies. The targeted panel sequencing approach allowed us to identify 87 (32 novel and 55 previously described) mutations in 78 patients, which generated a diagnostic success rate of 28.4%. Specifically, mutations in DOCK8 (26 patients), STAT3 (21), STAT1 (15), CARD9 (6), AIRE (3), IL17RA (2), SPINK5 (3), ZNF341 (2), CARMIL2/RLTPR (1), IL12RB1 (1), and WAS (1) have been detected. The most common clinical findings in this cohort were elevated IgE (81.5%), eczema (71.7%), and eosinophilia (62.9%). Regarding infections, 54.7% of patients had a history of radiologically proven pneumonia, and 28.3% have had other serious infections. History of fungal infection was noted in 53% of cases and skin abscesses in 52.9%. Skeletal or dental abnormalities were observed in 46.2% of patients with a characteristic face being the most commonly reported feature (23.1%), followed by retained primary teeth in 18.9% of patients. Targeted panel sequencing provides a cost-effective first-line genetic screening method which allows for the identification of mutations also in patients with atypical clinical presentations and should be routinely implemented in referral centers.

Incidence and predictors of COVID-19 and flares in patients with rare autoimmune diseases: a systematic survey and serological study at a national reference center in France

Background

The risk of severe COVID-19 and its determinants remain largely unknown in patients with autoimmune and inflammatory rheumatic diseases. The objective of this study was to assess the prevalence of COVID-19 infection in patients followed for rare autoimmune diseases as well as the predictors of COVID-19 and disease flare-ups.

Methods

Cross-sectional phone survey from April 9, 2020, to July 2, 2020, during which patients with autoimmune diseases followed at the National Reference Center for Rare Autoimmune diseases of Strasbourg were systematically contacted by phone and sent a prescription for a SARS-CoV-2 serology.

Results

One thousand two hundred thirty-two patients were contacted. One thousand fifty-five patients with a confirmed diagnosis of systemic autoimmune disease were included (4 unreachable, 4 moves abroad, 5 deaths before pandemic, 50 without consent, and 114 without autoimmune disease). Among them, 469 (44.5%) patients were tested for SARS-CoV-2 serology.

Thirty-nine patients (7.9%) had SARS-CoV-2 infection (either through chest CT-scan [n = 5], RT-PCR on nasopharyngeal swab [n = 14], or serology [n = 31]) among the 496 who underwent at least one of those 3 diagnosis modalities. Of the 39 proven cases, 33 had clinical manifestations (6 asymptomatic patients were diagnosed through systematic serology testing), 31 were managed by home care, 3 were hospitalized due to a need for oxygenation, two required admission to an intensive care unit, and one died. Among patients with confirmed SARS-CoV-2 infection, reported flares were more frequent than in uninfected patients (26.3% [10/38] vs. 7.0% [32/457], p < 0.0001). Preventive sick leave had no significant impact on the prevalence of SARS-CoV-2 infection (5.8% [3/53]) compared to work continuation (7.6% [30/397], p = 0.64).

Overall, the seroprevalence of SARS-CoV-2 was 6.6% (31/469) which was numerically lower to the Grand-Est general population estimated to be 9.0%.

Conclusions

This systematic survey of more than 1000 patients with rare systemic autoimmune diseases reports a low prevalence of proven SARS-CoV-2 infection and very rare severe infections, probably related to good compliance with prophylactic measures in these patients.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13075-021-02565-0.

Significance of Sjögren's syndrome and anti-cN1A antibody in myositis patients

OBJECTIVE

We recently recorded a high prevalence of inclusion body myositis (IBM) in patients with Sjögren's syndrome (SS). Whether myositis patients with SS differ from myositis patients without SS in terms of the characteristics of the myositis is currently unknown. Anti-cytosolic 5'-nucleotidase 1 A (cN1A) has recently been proposed as a biomarker for IBM but is also frequent in SS. Whether anti-cN1A is independently associated with IBM is still an open question. We aimed to assess the significance of SS and anti-cN1A in myositis patients.

METHODS

Cumulative data on all myositis patients (EULAR/ACR 2017 criteria) screened for SS (ACR/EULAR 2016 criteria) in a single center were analyzed. Ninety-nine patients were included, covering the whole spectrum of EULAR/ACR 2017 myositis subgroups and with a median follow-up of 6 years [range 1.0-37.5]. The 34 myositis patients with SS (myositis/SS+) were compared with the 65 myositis patients without SS (myositis/SS-).

RESULTS

IBM was present in 24% of the myositis/SS+ patients vs 6% of the myositis/SS- group (p = 0.020). None of the IBM patients responded to treatment, whether they had SS or not. Anti-cN1A was more frequent in myositis/SS+ patients (38% vs 6%, p = 0.0005), independently of the higher prevalence of IBM in this group (multivariate p-value: 0.02). Anti-cN1A antibody specificity for IBM was 0.96 [95% CI, 0.87-0.99] in the myositis SS- group but dropped to 0.70 [95% CI, 0.48-0.85] in the myositis SS/+ group.

INTERPRETATION

In myositis patients, SS is associated with IBM and with anti-cN1A antibodies, independently of the IBM diagnosis. As a consequence, anti-cN1A has limited specificity for IBM in myositis patients with SS.

Systemic lupus erythematosus and neutropaenia: a hallmark of haematological manifestations

Objective

Systemic lupus is a chronic autoimmune disease characterised by its phenotypic heterogeneity. Neutropaenia is a frequent event in SLE occurring in 20%–40% of patients depending on the threshold value of neutrophil count. On a daily basis, the management of neutropaenia in SLE is difficult with several possible causes. Moreover, the infectious consequences of neutropaenia in SLE remain not well defined.

Methods

998 patients from the Lupus BioBank of the upper Rhein (LBBR), a large German and French cohort of patients with SLE, mostly of Caucasian origin (83%), were included in this study. Neutropaenia was considered when neutrophil count was below 1800×10⁶/L. An additional analysis of detailed medical records was done for 65 LBBR patients with neutropaenia.

Results

208 patients with neutropaenia (21%) were compared with 779 SLE patients without neutropaenia. Neutropaenia in SLE was significantly associated with thrombocytopaenia (OR 4.11 (2.57–10.3)), lymphopaenia (OR 4.41 (2.51–11.5)) and low C3 (OR 1.91 (1.03–4.37)) in multivariate analysis. 65 representative patients with neutropaenia were analysed. Neutropaenia was moderate to severe in 38%, chronic in 31%, and both severe and chronic in 23% of cases. Moderate to severe and chronic neutropaenia were both associated with lymphopaenia and thrombopaenia. Chronic neutropaenia was also associated anti-Ro/SSA antibodies and moderate to severe neutropaenia with oral ulcers.

Conclusion

This study is to date the largest cohort to describe neutropaenia in SLE. Neutropaenia displays a strong association with other cytopaenias, suggesting a common mechanism. Chronic neutropaenia is associated with anti-Ro/SSA antibodies with or without identified Sjögren’s disease.

Implication of a lysosomal antigen in the pathogenesis of lupus erythematosus

Naturally-occurring autoantibodies to certain components of autophagy processes have been described in a few autoimmune diseases, but their fine specificity, their relationships with clinical phenotypes, and their potential pathogenic functions remain elusive. Here, we explored IgG autoantibodies reacting with a panel of cytoplasmic endosomal/lysosomal antigens and individual heat-shock proteins, all of which share links to autophagy. Sera from autoimmune patients and from MRL/lpr and NZB/W lupus-prone mice reacted with the C-terminal residues of lysosome-associated membrane glycoprotein (LAMP)2A. No cross-reaction was observed with LAMP2B or LAMP2C variants, with dsDNA or mononucleosomes, or with heat-shock protein A8. Moreover, administering chromatography-purified LAMP2A autoantibodies to MRL/lpr mice accelerated mortality. Furthermore, flow cytometry revealed elevated cell-surface expression of LAMP2A on MRL/lpr B cells. These findings reveal the involvement of a new class of autoantibodies targeting the C-terminus of LAMP2A, a receptor for cytosolic proteins targeted for degradation via chaperone-mediated autophagy. These autoantibodies could affect the autophagy process, which is abnormally upregulated in lupus. The data presented support a novel connection between autophagy dysregulation, autoimmune processes and pathophysiology in lupus.

Prevalence of antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis and spatial association with quarries in a French Northeast region

OBJECTIVE

Silica is one of the strongest environmental substances linked with autoimmunity. The aim of this study was to assess the prevalence of granulomatosis with polyangiitis (GPA), microscopic polyangiitis (MPA) and renal limited vasculitis (RLV) in a French northeast region, and their geospatial association with quarries.

METHODS

Potential ANCA-Associated Vasculitis (AAV) cases were identified using three sources: hospital records, immunology laboratories and the National Health Insurance System. Patients who resided in Alsace on January 1, 2016 and fulfilled ACR AAV criteria or Chapel Hill Consensus Conference 2012 definition were included. Incomplete case ascertainment was corrected using capture-recapture analysis. The spatial association between the number of cases and quarries in each administrative entity was assessed using geographical weighted regression (GWR).

RESULTS

From 910 potential AAV cases, we identified 185 patients meeting inclusion criteria: 120 GPA, 35 MPA, 30 RLV. The number of cases missed by any source was 6.4 (95%CI 3.6-11.5). Accordingly, the 2016 estimated prevalence in Alsace was 65.5 cases per million inhabitants (95%CI 47.3-93.0) for GPA, 19.1 (95%CI 11.3-34.3) for MPA, and 16.8 (95%CI 8.7-35.2) for RLV. The risk of AAV was significantly increased in communes with quarries (OR: 2.51 [95%CI: 1.66-3.80]) and GWR revealed a significant spatial association between quarries and GPA cases (p = 0.039), and, regarding ANCA serotype, between quarries and both PR3-AAV (p = 0.04) and MPO-AAV (p = 0.03)."

CONCLUSION

In a region with a high density of quarries, the spatial association of AAV with quarries supports the role of silica as a specific environmental factor.

B cells in primary antiphospholipid syndrome: Review and remaining challenges

It is now widely accepted that antiphospholipid antibodies (aPL) have direct pathogenic effects and that B cells, notably through aPL production, play a key role in the development of antiphospholipid syndrome (APS). Recent findings strengthened the implication of B cells with the description of specific B cell phenotype abnormalities and inborn errors of immunity involving B cell signaling in APS patients. In addition, it has been shown in preclinical models that cross-reactivity between APS autoantigens and mimotopes expressed by human gut commensals can lead to B cell tolerance breakdown and are sufficient for APS development. However, B cell targeting therapies are surprisingly not as effective as expected in APS compared to other autoimmune diseases. Elucidation of the B cell tolerance breakdown mechanisms in APS patients may help to develop and guide the use of novel therapeutic agents that target B cells or specific immune pathway.

Severe pulmonary arterial hypertension and massive ascites in a patient with systemic lupus erythematosus and secondary Sjogren's syndrome

BACKGROUND

Pulmonary arterial hypertension (PAH), is a rare manifestation of systemic lupus erythematosus (SLE), characterized by pulmonary arterial remodeling leading to right ventricular failure and death. To date, optimal management of SLE-associated PAH should be clarified, especially regarding the respective places of immunosuppressants and PAH vasodilator treatments.

CASE REPORT

We report the case of a 48-year-old woman with SLE and secondary Sjogren syndrome, associated with severe PAH and lupus peritonitis with massive ascites, who showed a remarkable response, both for SLE flare and PAH, to a treatment combining immunosuppressants and pulmonary arterial vasodilator treatment.

CONCLUSION

This observation highlights the interest of combining immunosuppressive therapy in SLE-PAH, whose modalities in association with PAH treatments should be clarified.

Progressive multifocal leukoencephalopathy and sarcoidosis under interleukin 7: The price of healing

Objective

To report the association of JC virus infection of the brain (progressive multifocal encephalopathy [PML]) during the course of sarcoidosis and the challenging balance between immune reconstitution under targeted cytokine interleukin 7 (IL7) therapy for PML and immunosuppression for sarcoidosis.

Methods

Original case report including deep sequencing (whole-exome sequencing) to exclude a primary immunodeficiency (PID) and review of the literature of cases of PML and sarcoidosis.

Results

We report and discuss here a challenging case of immune reconstitution with IL7 therapy for PML in sarcoidosis in a patient without evidence for underling PID or previous immunosuppressive therapy.

Conclusions

New targeted therapies in immunology and infectiology open the doors of more specific and more specialized therapies for patients with immunodeficiencies, autoimmune diseases, or cancers. However, before instauration of these treatments, the risk of immune reconstitution inflammatory syndrome and potential exacerbation of an underlying disease must be considered. It is particularly true in case of autoimmune disease such as sarcoidosis or lupus.

Beyond Anti-viral Effects of Chloroquine/Hydroxychloroquine

As the world is severely affected by COVID-19 pandemic, the use of chloroquine and hydroxychloroquine in prevention or for the treatment of patients is allowed in multiple countries but remained at the center of much controversy in recent days. This review describes the properties of chloroquine and hydroxychloroquine, and highlights not only their anti-viral effects but also their important immune-modulatory properties and their well-known use in autoimmune diseases, including systemic lupus and arthritis. Chloroquine appears to inhibit in vitro SARS virus' replication and to interfere with SARS-CoV2 receptor (ACE2). Chloroquine and hydroxychloroquine impede lysosomal activity and autophagy, leading to a decrease of antigen processing and presentation. They are also known to interfere with endosomal Toll-like receptors signaling and cytosolic sensors of nucleic acids, which result in a decreased cellular activation and thereby a lower type I interferons and inflammatory cytokine secretion. Given the antiviral and anti-inflammatory properties of chloroquine and hydroxychloroquine, there is a rational to use them against SARS-CoV2 infection. However, the anti-interferon properties of these molecules might be detrimental, and impaired host immune responses against the virus. This duality could explain the discrepancy with the recently published studies on CQ/HCQ treatment efficacy in COVID-19 patients. Moreover, although these treatments could be an interesting potential strategy to limit progression toward uncontrolled inflammation, they do not appear per se sufficiently potent to control the whole inflammatory process in COVID-19, and more targeted and/or potent therapies should be required at least in add-on.

Primary Immunodeficiencies With Defects in Innate Immunity: Focus on Orofacial Manifestations

The field of primary immunodeficiencies (PIDs) is rapidly evolving. Indeed, the number of described diseases is constantly increasing thanks to the rapid identification of novel genetic defects by next-generation sequencing. PIDs are now rather referred to as “inborn errors of immunity” due to the association between a wide range of immune dysregulation-related clinical features and the “prototypic” increased infection susceptibility. The phenotypic spectrum of PIDs is therefore very large and includes several orofacial features. However, the latter are often overshadowed by severe systemic manifestations and remain underdiagnosed. Patients with impaired innate immunity are predisposed to a variety of oral manifestations including oral infections (e.g., candidiasis, herpes gingivostomatitis), aphthous ulcers, and severe periodontal diseases. Although less frequently, they can also show orofacial developmental abnormalities. Oral lesions can even represent the main clinical manifestation of some PIDs or be inaugural, being therefore one of the first features indicating the existence of an underlying immune defect. The aim of this review is to describe the orofacial features associated with the different PIDs of innate immunity based on the new 2019 classification from the International Union of Immunological Societies (IUIS) expert committee. This review highlights the important role played by the dentist, in close collaboration with the multidisciplinary medical team, in the management and the diagnostic of these conditions.

Immune Defect in Adults With Down Syndrome: Insights Into a Complex Issue

Children with Down syndrome (DS) suffer from recurrent respiratory infections, which represent the leading cause of mortality during childhood. This susceptibility to infections is usually considered multifactorial and related to both impaired immune function and non-immunological factors. Infections are also one of the top causes of death in DS at adulthood. DS is considered an immunodeficiency with syndromic features by some researchers because of this high rate of infection and the immunological characteristics observed in children with DS. Little is known about the immune status of adult patients. Herein, we report the clinical and immune phenotype of 44 adults with DS, correlated with their infectious history. We observed that these adults had an aberrant lymphocyte phenotype with decreased naïve/memory T cell ratios and reduced numbers of switched memory B cells. The lower incidence of infectious events at adulthood distinguish DS from other inborn errors of immunity. Primary immunodeficiency-related features in DS could explain the increased risk of developing autoimmunity, malignancies, and infections. During adulthood, this immune dysfunction may be compensated for in mid-life, and infection-related mortality observed in older patients might be favored by multiple factors such as neurological impairment or nosocomial antigen exposure.

Clinical Trial Registration:www.ClinicalTrials.gov, identifier NCT01663675 (August 13, 2012).

Worldwide trends in all-cause mortality of auto-immune systemic diseases between 2001 and 2014

AIM

To describe changes in the 2001-2014 mortality of 6 autoimmune systemic diseases (AISDs), namely Systemic Lupus Erythematosus (SLE), Systemic Sclerosis (SSc), Idiopathic Inflammatory Myopathies (IIM), Sjögren's Syndrome (SS), Mixed Connective Tissue Disease (MCTD) and ANCA-associated vasculitis (AAV) at the country-, continent-, and world-levels.

METHODS

Mortality data were retrieved from the World Health Organization (WHO) mortality database for each disease, based on ICD-10 codes. We computed age-standardized mortality rate (ASMR) as the estimated number of deaths per million inhabitants and its 95% confidence interval (95%CI). The association between gender, geographical areas and disease-specific mortality was analyzed using multivariate Poisson regression. The 2001-2014 temporal trends were analyzed using Jointpoint software.

RESULTS

In 2014, the worldwide ASMR for SLE was 2.68 (95%CI: 2.62-2.75) deaths/millions inhabitants, 1.46 (1.42-1.51) for SSc, 0.47 (0.44-0.49) for IIM, 0.17 (0.15-0.18) for SS, 0.11 (0.10-0.13) for MCTD and 0.53 (0.50-0.56) for AAV, with ASMRs generally lower in Europe than in North America, Latin America and Asia. Between 2001 and 2014, the worldwide ASMR decreased significantly for SSc (-0.71%/year), IIM (-1.65%/year) and AAV (-1.01%/year; p < .001 for all) and increased for SS (+1.53%/year, p = .01). The worldwide ASMR of SLE decreased significantly between 2001 and 2003 (-6.37%, p < .05) before increasing slightly between 2004 and 2014 (+0.58%, p < .01).

CONCLUSIONS

We observed a strong heterogeneity of standardized mortality rates across all countries analyzed for 6 autoimmune diseases. Those results further highlight the impact of world-wide inequities and major gaps in access to care and strategies for diagnosis and management of rare diseases, a crucial finding for world-wide physicians, patient associations and policy makers.

Control of TLR7-mediated type I IFN signaling in pDCs through CXCR4 engagement-A new target for lupus treatment

Type I interferons are highly potent cytokines essential for self-protection against tumors and infections. Deregulations of type I interferon signaling are associated with multiple diseases that require novel therapeutic options. Here, we identified the small molecule, IT1t, a previously described CXCR4 ligand, as a highly potent inhibitor of Toll-like receptor 7 (TLR7)-mediated inflammation. IT1t inhibits chemical (R848) and natural (HIV) TLR7-mediated inflammation in purified human plasmacytoid dendritic cells from blood and human tonsils. In a TLR7-dependent lupus-like model, in vivo treatment of mice with IT1t drives drastic reduction of both systemic inflammation and anti-double-stranded DNA autoantibodies and prevents glomerulonephritis. Furthermore, IT1t controls inflammation, including interferon α secretion, in resting and stimulated cells from patients with systemic lupus erythematosus. Our findings highlight a groundbreaking immunoregulatory property of CXCR4 signaling that opens new therapeutic perspectives in inflammatory settings and autoimmune diseases.

T1 mapping cardiac magnetic resonance imaging frequently detects subclinical diffuse myocardial fibrosis in systemic sclerosis patients

OBJECTIVES

cardiac involvement is the second most frequent systemic sclerosis (SSc) related cause of death. It remains mostly asymptomatic in the early stage and is underdiagnosed with routine screening. Cardiac magnetic resonance imaging (CMR) could improve cardiac assessment of patients and noteworthily, new sequences allow the detection of diffuse myocardial fibrosis (DMF) by native T1 mapping. The aim of this study was to determine the prevalence of cardiac involvement by CMR native T1 mapping and its correlation with echocardiography data and non-cardiac manifestations in SSc patients.

METHODS

patients fulfilling the ACR/EULAR classification criteria for SSc were prospectively included between 2014 and 2016. They underwent CMR at 1.5T, including native T1 and T2 mapping, and Late Gadolinium Enhancement (LGE) as a part of routine follow up. Routine biological tests (mainly BNP and CRP) were centralized in the hospital laboratory.

RESULTS

seventy-two unselected patients were included. Thirty six patients (50%) had elevated T1 (ET1) (mean T1 1097±14 ms). CMR cardiac functional parameters were similar in ET1 and normal T1 (NT1). Echocardiography was normal in 18 (50%) of ET1. ET1 and NT1 groups were similar for cardiovascular risk factors and ischemic heart disease. ET1 was not correlated with any clinical or echocardiographic parameter or antibody profile. Thirty-six percent of patients with ET1 had no cardiac symptoms, normal echocardiography and CMR LVEF, and no LGE.

CONCLUSION

native T1 mapping detects left ventricular ET1 (potential DMF) in 50% of patients with SSc and a third of them had a normal conventional screening including standard CMR. In the future, further studies are needed to confirm the benefit of use of native T1 mapping as a part of routine follow up to detect earlier pejorative cardiac involvement in SSc patients.

Infection risk among adults with down syndrome: a two group series of 101 patients in a tertiary center

Background

Down syndrome (DS) is the most common form of viable chromosomal abnormality. DS is associated with recurrent infections, auto-immunity and malignancies in children. Little is known about immunity and infections in DS at adulthood.

Methods

We studied two separate group of adults (> 18 years old) with DS in a single referral tertiary center (Strasbourg University Hospital). The first group included 37 ambulatory DS patients between November 2014 and May 2017. We analyzed exhaustive serological and immunobiological parameters, at one point, together with the prevalence of infections, autoimmune manifestations and malignancies. The second group included 64 hospitalized patients (138 stays) in the same center, between January 2005 and December 2016.

Results

One hundred and one adult patients with DS were included. Unlike children and despite a global lymphopenia, adults with DS underwent few infections in our ambulatory group. They did not experience any malignancy and, apart from hypothyroidism, they presented only occasional autoimmune manifestations. Hospitalized DS patients were older than ambulatory ones (median age 47 years (18–73) vs. 27 (18–52), p < 0.0001) and admitted mostly for infections (76.8%). Infections were associated with epilepsy and dementia (OR 6.5 (2.2–19), p = 0.001; p = 0.0006 in multivariate analysis) and higher mortality (OR 7.4 (1.4–37), p = 0.01).

Conclusion

Despite persistent immunobiological abnormalities at adulthood, young ambulatory adults with DS remain healthy with a low rate of infections. Infections are associated with neurological degeneration and increase the mortality arguing for a dedicated support of older DS patients.

Trial registration

ClinicalTrials.gov: NCT01663675 (August 13, 2012). Hospital Clinical Research Program (PHRC): number 2012-A00466–37 (Dr Y. Alembik).

Electronic supplementary material

The online version of this article (10.1186/s13023-018-0989-x) contains supplementary material, which is available to authorized users.

10 most important contemporary challenges in the management of SLE

From a 1-year survival of less than 50% before the discovery of glucocorticoids to over 90% at 10 years in most dedicated centres, the spectrum of SLE has profoundly evolved. Despite this improvement, several major challenges currently remain. The aim of this review is to analyse what are, according to us, the 10 most important contemporary challenges in the management of SLE. Among those are the need to treat to target to favour disease remission (or low disease activity), limit the use of glucocorticoids, derive more comprehensive tools for the evaluation of disease activity, develop more effective drugs (yielding successful trials), dissect the heterogeneity of the disease both at the molecular and genetic levels, identify relevant biomarkers for individualised treatment, manage fertility and pregnancy, tackle comorbidities such as cardiovascular risk, the prevention of infections and osteoporosis, improve the network of care (from the patients’ perspective), and favour a holistic approach (integrating fatigue, adherence to treatment, physical activity). Altogether, these 10 contemporary challenges in SLE may be considered as a roadmap for those involved in the daily care of patients with SLE, as well as for researchers who may wish to contribute to an improved management of this rare and complex disease.

Rare diseases that mimic Systemic Lupus Erythematosus (Lupus mimickers)

Several conditions have clinical and laboratory features that can mimic those present in Systemic Lupus Erythematosus (SLE). Some of these "SLE mimickers" are very common, such as rosacea which can be mistaken for the butterfly rash, while others such as Kikuchi disease, type-1 interferonopathies, Castleman's disease, prolidase deficiency, angioimmunoblastic T-cell lymphoma, Evans' syndrome in the context of primary immune deficiencies and the autoimmune lymphoproliferative syndrome are exceptionally uncommon. A proper diagnosis of SLE must therefore be based upon a complete medical history as well as on the adequate constellation of clinical or laboratory findings. While there is no single test that determines whether a patient has lupus or not, the search for auto-antibodies towards nuclear antigens is a key step in the diagnosis strategy, keeping in mind that ANAs are not specific for SLE. In case of persistent doubt, patients should be referred to reference centers with experience in the management of the disease.

Adolescents and young adults (AYAs) affected by chronic immunological disease: A tool-box for success during the transition to adult care

Adolescence is a time of physical, psychological and social changes between childhood and adulthood. All adolescents and young adults (AYAs) are in transition and experience key underlying processes that will influence their later life. It is a critical period, particularly for AYAs with a chronic medical condition. Diseases can start at any point during adolescence. The transition of care will concern health care providers, as well as more unexpected actors such as social workers, teachers, business managers and the family. In this review, we focus on transition in primary immunodeficiencies (PIDs) and autoimmune diseases (AIDs). We describe the challenges and needs of transition in the field. Questions that AYAs with PID and/or AID must face during transition in their familial, professional and personal life are discussed. We expose a practical, AYA centered approach to help physicians in their daily practice, and we propose a position for the future.

Characteristics and clinical outcomes after treatment of a national cohort of PCR-positive Lyme arthritis

OBJECTIVES

To describe the clinical and microbiological characteristics and outcomes after antibiotic treatment of a national cohort of patients with Lyme arthritis confirmed by PCR testing on synovial fluid and by serology, when available.

METHODS

Using the French National Reference Center for Borrelia database, patients with a positive PCR on synovial fluid for Borrelia were identified. Patient clinical and biological characteristics were reviewed from patient records. Long-term outcomes after treatment were studied through a questionnaire and with follow-up data.

RESULTS

Among 357 synovial fluid testing by PCR between 2010 and 2016, 37 (10.4%) were positive for Borrelia. Patients' median age was 36 years (range 6-78) with 61% of men and 28% patients under 18. The presentation was monoarticular in 92% and the knee was involved in 97%. Contrary to the Borrelia species repartition in European ticks, B. burgdorferi sensu stricto was the most prevalent species found in synovial fluid (54%) followed by B. azfelii (29%) and B. garinii (17%). Antibiotic treatments were mainly composed of doxycycline (n = 24), ceftriaxone (n = 10) and amoxicillin (n = 6), for a median duration of 4 weeks (range 3-12). Despite a properly conducted treatment, 34% of patients (n = 12) developed persistent synovitis for at least 2 months (median duration 3 months, range 2-16). Among those, 3 developed systemic inflammatory oligo- or polyarthritis in previously unaffected joints with no signs of persistent infection (repeated PCR testing negative), which mandated Disease-Modifying Antirheumatic Drugs (DMARD) introduction, leading to remission.

CONCLUSION

In France and contrary to ticks ecology, Lyme arthritis is mainly caused by B. burgdorferi sensu stricto. Despite proper antibiotic therapy, roughly one third of patients may present persistent inflammatory synovitis and a small proportion may develop systemic arthritis. In such cases, complete remission can be reached using DMARD.

Severe combined immunodeficiency in stimulator of interferon genes (STING) V154M/wild-type mice

BACKGROUND

Autosomal dominant gain-of-function mutations in human stimulator of interferon genes (STING) lead to a severe autoinflammatory disease called STING-associated vasculopathy with onset in infancy that is associated with enhanced expression of interferon-stimulated gene transcripts.

OBJECTIVE

The goal of this study was to analyze the phenotype of a new mouse model of STING hyperactivation and the role of type I interferons in this system.

METHODS

We generated a knock-in model carrying an amino acid substitution (V154M) in mouse STING, corresponding to a recurrent mutation seen in human patients with STING-associated vasculopathy with onset in infancy. Hematopoietic development and tissue histology were analyzed. Lymphocyte activation and proliferation were assessed in vitro. STING V154M/wild-type (WT) mice were crossed to IFN-α/β receptor (IFNAR) knockout mice to evaluate the type I interferon dependence of the mutant Sting phenotype recorded.

RESULTS

In STING V154M/WT mice we detected variable expression of inflammatory infiltrates in the lungs and kidneys. These mice showed a marked decrease in survival and developed a severe combined immunodeficiency disease (SCID) affecting B, T, and natural killer cells, with an almost complete lack of antibodies and a significant expansion of monocytes and granulocytes. The blockade in B- and T-cell development was present from early immature stages in bone marrow and thymus. In addition, in vitro experiments revealed an intrinsic proliferative defect of mature T cells. Although the V154M/WT mutant demonstrated increased expression of interferon-stimulated genes, the SCID phenotype was not reversed in STING V154M/WT IFNAR knockout mice. However, the antiproliferative defect in T cells was rescued partially by IFNAR deficiency.

CONCLUSIONS

STING gain-of-function mice developed an interferon-independent SCID phenotype with a T-cell, B-cell, and natural killer cell developmental defect and hypogammaglobulinemia that is associated with signs of inflammation in lungs and kidneys. Only the intrinsic proliferative defect of T cells was partially interferon dependent.

Trib1 Is Overexpressed in Systemic Lupus Erythematosus, While It Regulates Immunoglobulin Production in Murine B Cells

Systemic lupus erythematosus (SLE) is a severe and heterogeneous autoimmune disease with a complex genetic etiology, characterized by the production of various pathogenic autoantibodies, which participate in end-organ damages. The majority of human SLE occurs in adults as a polygenic disease, and clinical flares interspersed with silent phases of various lengths characterize the usual evolution of the disease in time. Trying to understand the mechanism of the different phenotypic traits of the disease, and considering the central role of B cells in SLE, we previously performed a detailed wide analysis of gene expression variation in B cells from quiescent SLE patients. This analysis pointed out an overexpression of TRIB1. TRIB1 is a pseudokinase that has been implicated in the development of leukemia and also metabolic disorders. It is hypothesized that Trib1 plays an adapter or scaffold function in signaling pathways, notably in MAPK pathways. Therefore, we planned to understand the functional significance of TRIB1 overexpression in B cells in SLE. We produced a new knock-in model with B-cell-specific overexpression of Trib1. We showed that overexpression of Trib1 specifically in B cells does not impact B cell development nor induce any development of SLE symptoms in the mice. By contrast, Trib1 has a negative regulatory function on the production of immunoglobulins, notably IgG1, but also on the production of autoantibodies in an induced model. We observed a decrease of Erk activation in BCR-stimulated Trib1 overexpressing B cells. Finally, we searched for Trib1 partners in B cells by proteomic analysis in order to explore the regulatory function of Trib1 in B cells. Interestingly, we find an interaction between Trib1 and CD72, a negative regulator of B cells whose deficiency in mice leads to the development of autoimmunity. In conclusion, the overexpression of Trib1 could be one of the molecular pathways implicated in the negative regulation of B cells during SLE.

Impaired TLR9 responses in B cells from patients with systemic lupus erythematosus

B cells play a central role in systemic lupus erythematosus (SLE) pathophysiology but dysregulated pathways leading to a break in B cell tolerance remain unclear. Since Toll-like receptor 9 (TLR9) favors the elimination of autoreactive B cells in the periphery, we assessed TLR9 function in SLE by analyzing the responses of B cells and plasmacytoid dendritic cells (pDCs) isolated from healthy donors and patients after stimulation with CpG, a TLR9 agonist. We found that SLE B cells from patients without hydroxychloroquine treatment displayed defective in vitro TLR9 responses, as illustrated by the impaired upregulation of B cell activation molecules and the diminished production of various cytokines including antiinflammatory IL-10. In agreement with CD19 controlling TLR9 responses in B cells, decreased expression of the CD19/CD21 complex on SLE B cells was detected as early as the transitional B cell stage. In contrast, TLR7 function was preserved in SLE B cells, whereas pDCs from SLE patients properly responded to TLR9 stimulation, thereby revealing that impaired TLR9 function in SLE was restricted to B cells. We conclude that abnormal CD19 expression and TLR9 tolerogenic function in SLE B cells may contribute to the break of B cell tolerance in these patients.

Defective Early B Cell Tolerance Checkpoints in Sjögren's Syndrome Patients

OBJECTIVE

Central and peripheral B cell tolerance checkpoints are defective in many patients with autoimmune diseases, but the functionality of each discrete checkpoint has not been assessed in patients with Sjögren's syndrome (SS). We undertook this study to assess this functionality in SS patients.

METHODS

Using a polymerase chain reaction-based approach that allows us to clone and express, in vitro, recombinant antibodies produced by single B cells, we tested the reactivity of recombinant antibodies cloned from single CD19+CD21^low CD10+IgM^high CD27- newly emigrant/transitional B cells and CD19+CD21+CD10-IgM+CD27- mature naive B cells from 5 SS patients.

RESULTS

We found that the frequencies of newly emigrant/transitional B cells expressing polyreactive antibodies were significantly increased in SS patients compared to those in healthy donors, revealing defective central B cell tolerance in SS patients. Frequencies of mature naive B cells expressing autoreactive antibodies were also significantly increased in SS patients, thereby illustrating an impaired peripheral B cell tolerance checkpoint in these patients.

CONCLUSION

Defective counterselection of developing autoreactive B cells observed in SS patients is a feature common to many other autoimmune diseases and may favor the development of autoimmunity by allowing autoreactive B cells to present self antigens to T cells.

[Thymic B cells: not simple bystanders of T cell lymphopoiesis]

The thymus is the central site for the differentiation and selection of T cells. It has been known for decades that B lymphocytes reside in the thymus, but little attention has been paid to this unique population. Thymic B cells are mainly located in the medulla and at the cortico-medullary junction. They develop intrathymically, do not recirculate and harbor a distinct phenotype in comparison to peripheral B cells. Furthermore, because of their activated phenotype and their precise histological localization, they have been suspected to play a role in the selection of self-reactive T cells. But it is only during this last decade that murine and human studies have highlighted their functions, such as antigen-presenting cells shaping the T cell repertoire. These works have demonstrated the major role of thymic B cells in the immune system.

History and Outcome of Febrile Neutropenia Outside the Oncology Setting: A Retrospective Study of 76 Cases Related to Non-Chemotherapy Drugs

BACKGROUND

Despite major advances in its prevention and treatment, febrile neutropenia remains a most concerning complication of cancer chemotherapy. Outside the oncology setting, however, only few data are currently available on febrile neutropenia related to non-chemotherapy drugs. We report here data on 76 patients with febrile neutropenia related to non-chemotherapy drugs, followed up in a referral center within a university hospital.

PATIENTS AND METHODS

Data from 76 patients with idiosyncratic drug-induced febrile neutropenia were retrospectively reviewed. All cases were extracted from a cohort study on agranulocytosis conducted at the Strasbourg University Hospital (Strasbourg, France).

RESULTS

Mean patient age was 52.2 years old (range: 18-93) and gender ratio (F/M) 1.6, with several comorbidities present in 86.8% of patients. The most common causative drugs were: antibiotics (37.4%), antithyroid drugs (17.2%), neuroleptic and anti-epileptic agents (13.1%), non-steroidal anti-inflammatory agents and analgesics (8%), and platelet aggregation inhibitors (8%). Main clinical presentations upon hospitalization included isolated fever (30%), sore throat, acute tonsillitis and sinusitis (18.4%), documented pneumonia (18.4%), septicemia (14.5%), and septic shock (6.6%). Mean neutrophil count at nadir was 0.13 × 10(9)/L (range: 0-0.48). While in hospital, 22 patients (28.9%) worsened clinically and required intensive care unit placement. All patients were promptly treated with broad-spectrum antibiotics, and 45 (59.2%) with hematopoietic growth factors. Mean duration of hematological recovery (neutrophil count ≥1.5 × 10(9)/L) was 7.5 days (range: 2-21), which was reduced to 0.7 days (range: 2-16) (p = 0.089) with hematopoietic growth factors. Outcome was favorable in 89.5% of patients, whereas eight died.

CONCLUSIONS

Like in oncology and myelosuppressive chemotherapy settings, idiosyncratic febrile neutropenia is typically serious, about 40% of patients exhibiting severe pneumonia, septicemia, and septic shock, with a mortality rate of 10%. Like in febrile, chemotherapy-related neutropenia, modern and timely management (immediate broad spectrum antibiotherapy, hematopoietic growth factors) may reduce infection-related mortality. All practitioners should be aware of this potential side-effect that may even occur in the event of "daily medication" exposure.

Clinical spectrum and therapeutic management of systemic lupus erythematosus-associated macrophage activation syndrome: A study of 103 episodes in 89 adult patients

OBJECTIVES

Macrophage activation syndrome (MAS) is a life-threatening hyperinflammatory syndrome that can occur during systemic lupus erythematosus (SLE). Data on MAS in adult SLE patients are very limited. The aim of this study is to describe the clinical characteristics, laboratory findings, treatments, and outcomes of a large series of SLE-associated MAS.

METHODS

We conducted a retrospective study that included 103 episodes of MAS in 89 adult patients with SLE.

RESULTS

103 episodes in 89 adult patients were analyzed. Median age at first MAS episode was 32 (18-80) years. MAS was inaugural in 41 patients (46%).Thirteen patients relapsed. Patients had the following features: fever (100% episodes), increased serum levels of AST (94.7%), LDH (92.3%), CRP (84.5%), ferritin (96%), procalcitonin (41/49 cases). Complications included myocarditis (n=22), acute lung injury (n=15) and seizures (n=11). In 33 episodes, patients required hospitalization in an ICU and 5 died. Thrombocytopenia and high CRP levels were associated independently with an increased risk for ICU admission. High dose steroids alone as first line therapy induced remission in 37/57 cases (65%). Additional medications as first or second line therapies included IV immunoglobulins (n=22), cyclophosphamide (n=23), etoposide (n=11), rituximab (n=3). Etoposide and cyclophosphamide-based regimens had the best efficacy.

CONCLUSION

MAS is a severe complication and is often inaugural. High fever and high levels of AST, LDH, CRP, ferritin and PCT should be considered as red flags for early diagnosis. High dose steroids lead to remission in two third of cases. Cyclophosphamide or etoposide should be considered for uncontrolled/severe forms.