Cyclophosphamide vs rituximab for eradicating inhibitors in acquired hemophilia A: A randomized trial in 108 patients

BACKGROUND

Acquired hemophilia A (AHA) is a rare autoimmune disorder due to autoantibodies against Factor VIII, with a high mortality risk. Treatments aim to control bleeding and eradicate antibodies by immunosuppression. International recommendations rely on registers and international expert panels.

METHODS

CREHA, an open-label randomized trial, compared the efficacy and safety of cyclophosphamide and rituximab in association with steroids in patients with newly diagnosed AHA. Participants were treated with 1 mg/kg prednisone daily and randomly assigned to receive either 1.5-2 mg/kg/day cyclophosphamide orally for 6 weeks, or 375 mg/m2 rituximab once weekly for 4 weeks. The primary endpoint was complete remission over 18 months. Secondary endpoints included time to achieve complete remission, relapse occurrence, mortality, infections and bleeding, and severe adverse events.

RESULTS

Recruitment was interrupted because of new treatment recommendations after 108 patients included (58 cyclophosphamide, 50 rituximab). After 18 months, 39 cyclophosphamide patients (67.2 %) and 31 rituximab patients (62.0 %) were in complete remission (OR 1.26; 95 % CI, 0.57 to 2.78). In the poor prognosis group (FVIII < 1 IU/dL, inhibitor titer > 20 BU mL-1), significantly more remissions were observed with cyclophosphamide (22 patients, 78.6 %) than with rituximab (12 patients, 48.0 %; p = 0.02). Relapse rates, deaths, severe infections, and bleeding were similar in the 2 groups. In patients with severe infection, cumulative doses of steroids were significantly higher than in patients without infection (p = 0.03).

CONCLUSION

Cyclophosphamide and rituximab showed similar efficacy and safety. As first line, cyclophosphamide seems preferable, especially in poor prognosis patients, as administered orally and less expensive.

FUNDING

French Ministry of Health.

CLINICALTRIALS

gov number: NCT01808911.

Difficult-to-treat primary immune thrombocytopenia in adults: Prevalence and burden. Results from the CARMEN-France registry

The aim of this study was to assess the prevalence and the burden of difficult-to-treat primary ITP (pITP), defined by the need for another ITP treatment after romiplostim and eltrombopag. Adult patients were selected in the prospective, real-world CARMEN-France registry up to December 2021. Out of 821 adult patients with pITP, 29 had difficult-to-treat ITP (3.5%; 95% confidence interval [CI]: 2.3%-4.8% in total; 7.6%; 95% CI: 4.9%-10.2% of patients needing ≥2nd line treatment). The 3-year cumulative incidence of bleeding, infection and thrombosis was 100%, 24.1% and 13.8% respectively. The median cumulative duration of hospital stays was 31 days (median follow-up: 30.3 months).

Clinical presentation, course, and prognosis of patients with mixed connective tissue disease: A multicenter retrospective cohort

OBJECTIVES

The objective of this study is to better characterize the features and outcomes of a large population of patients with mixed connective tissue disease (MCTD).

METHODS

We performed an observational retrospective multicenter cohort study in France. Patients who fulfilled at least one diagnostic criterion set for MCTD and none of the criteria for other differentiated CTD (dCTD) were included.

RESULTS

Three hundred and thirty patients (88% females, median [interquartile range] age of 35 years [26-45]) were included. The diagnostic criteria of Sharp or Kasukawa were met by 97.3% and 93.3% of patients, respectively. None met other classification criteria without fulfilling Sharp or Kasukawa criteria. After a median follow-up of 8 (3-14) years, 149 (45.2%) patients achieved remission, 92 (27.9%) had interstitial lung disease, 25 (7.6%) had pulmonary hypertension, and 18 (5.6%) died. Eighty-five (25.8%) patients progressed to a dCTD, mainly systemic sclerosis (15.8%) or systemic lupus erythematosus (10.6%). Median duration between diagnosis and progression to a dCTD was 5 (2-11) years. The presence at MCTD diagnosis of an abnormal pattern on nailfold capillaroscopy (odds ratio [OR] = 2.44, 95% confidence interval [95%CI] [1.11-5.58]) and parotid swelling (OR = 3.86, 95%CI [1.31-11.4]) were statistically associated with progression to a dCTD. Patients who did not progress to a dCTD were more likely to achieve remission at the last follow-up (51.8% vs. 25.9%).

CONCLUSIONS

This study shows that MCTD is a distinct entity that can be classified using either Kasukawa or Sharp criteria, and that only 25.8% of patients progress to a dCTD during follow-up.

Regulatory T-cell dysfunctions are associated with increase in tumor necrosis factor α in autoimmune hemolytic anemia and participate in Th17 polarization

Warm autoimmune hemolytic anemia (wAIHA) is a rare acquired autoimmune disease mediated by antibodies targeting red blood cells. The involvement of CD4 T-helper cells has been scarcely explored, with most findings extrapolated from animal models. Here, we performed quantification of both effector T lymphocytes (Teff) and regulatory T cells (Treg), associated with functional and transcriptomic analyses of Treg in human wAIHA. We observed a shift of Teff toward a Th17 polarization concordant with an increase in serum interleukin-17 concentration that correlates with red blood cell destruction parameters, namely lactate dehydrogenase and bilirubin levels. A decrease in circulating Treg, notably effector Treg, associated with a functional deficiency, as represented by their decrease capability to inhibit Teff proliferation, were also observed. Treg deficiency was associated with a reduced expression of Foxp3, the master transcription factor known to maintain the Treg phenotype stability and suppressive functions. Transcriptomic profiling of Treg revealed activation of the tumor necrosis facto (TNF)-α pathway, which was linked to increased serum TNF-α concentrations that were twice as high as in controls. Treg transcriptomic profiling also suggested that post-translational mechanisms possibly accounted for Foxp3 downregulation and Treg dysfunctions. Since TNF-α participates in the rupture of immune tolerance during wAIHA, its inhibition could be of interest. To this end, the effects of fostamatinib, a SYK inhibitor, were investigated in vitro, and we showed that besides the inhibition of erythrocyte phagocytosis by monocytes, fostamatinib is also able to dampen TNF-α production, thus appearing as a promising multitargeting therapy in wAIHA (clinicaltrials gov. Identifier: NCT02158195).

Giant cell arteritis associated with scalp, tongue or lip necrosis: A French multicenter case control study

BACKGROUND

Scalp, tongue and/or lip necrosis are rare complications of GCA.

OBJECTIVES

To describe characteristics and outcome of patients with giant cell arteritis (GCA) -related scalp, tongue and/or lip necrosis.

METHODS

A retrospective nationwide multicenter study included 20 GCA patients with scalp, tongue, and/or lip necrosis diagnosed between 1998 and 2021 and 80 GCA control patients matched for age, sex and management period. Logistic regression analyses were conducted to identify baseline characteristics associated with scalp, tongue and/or lip necrosis.

RESULTS

Compared to controls, patients with scalp, tongue and/or lip necrosis showed significantly more cranial manifestations (headache, p=0.045; scalp tenderness, p=0.006; jaw claudication, p=0.02). No differences were observed between both groups regarding the occurrence of visual symptoms or large vessel involvement. At diagnosis, GCA patients with necrosis more likely received IV methylprednisolone infusions and higher doses of oral prednisone. There were no differences regarding vascular complications during follow up. Compared to controls, survival was decreased in GCA patients with necrosis (p=0.003). In a multivariable logistic regression model, scalp tenderness [odds ratio (OR) 4.81(95 % CI: 1.57, 14.79), p = 0.006] and cognitive disorder [OR 6.42 (95 % CI: 1.01, 40.60), p=0.048] were identified as factors associated to scalp, tongue, and/or lip necrosis.

CONCLUSION

Our results suggest that scalp, tongue, and/or lip necrosis is associated to higher mortality in GCA patients. Scalp tenderness and cognitive disorder were significant factors associated to this very rare complication of GCA.

Rituximab as maintenance therapy for ANCA-associated vasculitides: pooled analysis and long-term outcome of 277 patients included in the MAINRITSAN trials

OBJECTIVE

To compare the long-term efficacy and safety of azathioprine (AZA), 18-month fixed-schedule rituximab (RTX), 18-month tailored RTX and 36-month RTX in preventing relapses in patients with antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis who achieved a complete remission after induction therapy. Patients treated with 36-month RTX received either a fixed or a tailored regimen for the first 18 months and a fixed regimen for the last 18 months (36-month fixed/fixed RTX and 36-month tailored/fixed RTX, respectively).

METHODS

The Maintenance of Remission using Rituximab in Systemic ANCA-associated Vasculitis (MAINRITSAN) trials sequentially compared: 18-month fixed-schedule RTX versus AZA (MAINRITSAN); 18-month fixed-schedule RTX versus 18-month tailored-RTX (MAINRITSAN2); and extended therapy to 36 months with four additional RTX infusions after MAINRITSAN2 versus placebo (MAINRITSAN3). Patients were then followed prospectively through month 84 and their data were pooled to analyse relapses and adverse events. The primary endpoint was relapse-free survival at month 84.

RESULTS

277 patients were enrolled and divided in 5 groups: AZA (n=58), 18-month fixed-schedule RTX (n=97), 18-month tailored-RTX (n=40), 36-month tailored/fixed RTX (n=42), 36-month fixed/fixed RTX (n=41). After adjustment for prognostic factors, 18-month fixed-schedule RTX was superior to AZA in preventing major relapses at month 84 (HR 0.38, 95% CI 0.20 to 0.71). The 18-month tailored-RTX regimen was associated with an increased risk of major relapse compared with fixed-schedule regimen (HR 2.92, 95% CI 1.43 to 5.96). The risk of major relapse was similar between 36-month fixed/fixed and 18-month fixed-RTX (HR 0.69, 95% CI 0.38 to 1.25).

CONCLUSIONS

According to these results, it appears that the 84-month remission rate is higher with an 18-month fixed RTX regimen compared with AZA and 18-month tailored RTX. Also, extending RTX to 36 months does not appear to reduce the long-term relapse rate compared with the 18-month fixed RTX regimen. However, as this study was underpowered to make this comparison, further prospective studies are needed to determine the potential long-term benefits of extending treatment in these patients.

Disease patterns and specific trajectories of anti-MDA5-related disease: a multicentre retrospective study of 70 adult patients

Introduction

This study aimed to provide an updated analysis of the different prognostic trajectories of patients with anti-melanoma differentiation-associated gene 5 (MDA5) antibodies.

Methods

Among a cohort of 70 patients, baseline characteristics and phenotypes, treatments and outcomes were analyzed. A Cox proportional hazards model was used to identify factors associated with poor outcomes, i.e., death or progressive disease at the last follow-up.

Results

Among the 70 patients, 45 were women, and 54 were Caucasian. A dermatologic involvement was observed in 58 (83%) patients, including 40 with MDA5 vasculopathy-related skin lesions. Muscular involvement was observed in 39 (56%) patients. Interstitial lung disease (ILD) was observed at baseline in 52 (74%) patients, including 23 (44%) who developed rapidly progressive (RP) ILD. Seven (10%) patients showed thromboembolic complications within the first weeks of diagnosis, and eight (11%) other patients developed a malignancy (4 before the diagnosis of anti-MDA5 disease). Poor outcomes were observed in 28 (40%) patients, including 13 (19%) deaths. Among the 23 patients with RP-ILD, 19 (79%) showed poor outcomes, including 12 (63%) who died. In multivariate analyses, RP-ILD (hazard ratio (HR), 95% CI: 8.24 [3.21-22], p<0.0001), the occurrence of thromboembolic events (HR: 5.22 [1.61-14.77], p=0.008) and the presence of any malignancy (HR: 19.73 [6.67-60], p<0.0001) were the three factors independently associated with poor outcomes.

Discussion

This new independent cohort confirms the presence of different clinical phenotypes of anti-MDA5 diseases at baseline and the poor prognosis associated with RP-ILD. Thromboembolic events and malignancies were also identified as prognostic factors.

Neointimal myofibroblasts contribute to maintaining Th1/Tc1 and Th17/Tc17 inflammation in giant cell arteritis

Vascular smooth muscle cells (VSMCs) have been shown to play a role in the pathogenesis of giant cell arteritis (GCA) through their capacity to produce chemokines recruiting T cells and monocytes in the arterial wall and their ability to migrate and proliferate in the neointima where they acquire a myofibroblast (MF) phenotype, leading to vascular stenosis. This study aimed to investigate if MFs could also impact T-cell polarization. Confocal microscopy was used to analyze fresh fragments of temporal artery biopsies (TABs). Healthy TAB sections were cultured to obtain MFs, which were then treated or not with interferon-gamma (IFN-γ) and tumor necrosis factor-alpha (TNF-α) and analyzed by immunofluorescence and RT-PCR. After peripheral blood mononuclear cells and MFs were co-cultured for seven days, T-cell polarization was analyzed by flow cytometry. In the neointima of GCA arteries, we observed a phenotypic heterogeneity among VSMCs that was consistent with a MF phenotype (α-SMA+CD90+desmin+MYH11+) with a high level of STAT1 phosphorylation. Co-culture experiments showed that MFs sustain Th1/Tc1 and Th17/Tc17 polarizations. The increased Th1 and Tc1 polarization was further enhanced following the stimulation of MFs with IFN-γ and TNF-α, which induced STAT1 phosphorylation in MFs. These findings correlated with increases in the production of IL-1β, IL-6, IL-12 and IL-23 by MFs. Our study showed that MFs play an additional role in the pathogenesis of GCA through their ability to maintain Th17/Tc17 and Th1/Tc1 polarizations, the latter being further enhanced in case of stimulation of MF with IFN-γ and TNF-α.

Correction: Full-field optical coherence tomography for the diagnosis of giant cell arteritis

[This corrects the article DOI: 10.1371/journal.pone.0234165.].

Pro-angiogenic changes of T-helper lymphocytes in hereditary hemorrhagic telangiectasia

Hereditary hemorrhagic telangiectasia (HHT) is a rare inherited disease due to heterozygous loss-of-function mutations on the BMP9/10 pathway (ENG, ACVRL1 or MADH4 mainly). HHT endothelial cells are prone to lose their quiescence, leading to progressive appearance of numerous telangiectases on skin and mucosa (complicated by epistaxis and anemia), and to larger arteriovenous malformations in lungs, liver and brain. HHT is also associated with T lymphocyte abnormalities, which are currently poorly understood. We quantified by flow-cytometry the main T lymphocyte circulating subsets in 40 HHT patients and 20 matched healthy controls. Immunostaining was done on 2 HHT skin telangiectases. Disruptions in T lymphocyte homeostasis was observed, characterized by increases in subsets known to promote angiogenesis: Th2 (1.38% vs 1.15%, p=0.021), Th17 (0.32% vs 0.22%, p=0.019 2) and Treg (4.94% vs 3.51%, p= 0.027). T angiogenic lymphocytes (Tang), defined as CD3+CD31+CXCR4+ T cells, were at similar levels in both groups, but the proportion of VEGF-A+ Tang after stimulation was higher in the HHT group compared to controls (68.2% vs 44.9%, p=0.012). The global HHT T lymphopenia predominantly affected the effector memory T-helper cells (200 vs 270 cells/mm3, p=0.017), and the lymphocytic infiltrate around HHT telangiectases consisted of memory T-helper cells. The Th17 circulating subset was positively correlated with the monthly epistaxis duration (r coefficient: +0,431, p=0.042), prospectively assessed. HHT T-helper lymphocytes are affected by several pro-angiogenic changes, potentially resulting from their recruitment by abnormal endothelial cells. They could constitute a biologically relevant source of VEGF-A and a valuable therapeutic target in HHT.

Efficacy and safety of two rituximab biosimilars for treating immune thrombocytopenia: a reference-product matched study

The emergence of rituximab biosimilars offers the prospect of significant savings to the healthcare system. However, these drugs have never been evaluated for treating immune thrombocytopenia (ITP). This was an observational, matched study. We included adults who received a rituximab biosimilar for ITP. Each rituximab-naïve biosimilar patient was matched with two controls from the historic ITP-ritux registry. For non-naïve patients, we compared the response to the biosimilar with that observed with the reference product. Response status was defined according to international criteria. We included 107 patients; 55 receiving Rixathon™ and 52 Truxima™. Three months after the first infusion of rituximab biosimilars, the overall response rate was 47/74 (63.5%) versus 76/142 (53.5%) for the matched controls receiving the reference product (p = .13). The 3-month overall response rate was 76.5% for Rixathon™ versus 51.5% for the matched control group (p = .01) and 21/40 (52.5%) for Truxima™ versus 41/74 (55.4%) for the matched controls (p = .81). For non-naïve patients, the response pattern was similar to that observed previously with the reference product. Safety was analogous to that observed with the reference product. Rituximab biosimilars seemed safe and effective for ITP treatment.

Specific blood monocyte distribution in histiocytoses correlates with vascular involvement and disease activity

Not available.

Dysregulation of neutrophil oxidant production and interleukin-1-related cytokines in granulomatosis with polyangiitis

OBJECTIVES

Neutrophils play a key role in ANCA-associated vasculitis, both as targets of autoimmunity and facilitators of vascular damage. In granulomatosis with polyangiitis (GPA), data regarding the production of reactive oxygen species (ROS) in neutrophils are unclear. Further, recent data suggests that ROS production could have an anti-inflammatory effect through the regulation of the inflammasome and IL-1-related cytokines. We aimed to analyse the ROS production in neutrophils from patients with GPA and investigate its association with IL-1-related cytokines and the autoantigen proteinase 3 (PR3).

METHODS

Seventy-two GPA patients with disease flare were included in the NEUTROVASC prospective cohort study. ROS production was evaluated in whole blood of patients with active GPA and compared with the same patients in remission or healthy controls. Associations between ROS production, PR3 membrane expression on neutrophils, serum levels of IL-1-related cytokines as well as inflammasome-related proteins were analyzed.

RESULTS

We observed a robust defect in ROS production by neutrophils from patients with active GPA compared with healthy controls, independent of glucocorticoid treatment. Serum levels of IL-1-related cytokines were significantly increased in GPA patients, particularly in patients with kidney involvement, and levels of these cytokines returned to normal after patients achieved remission. Further, inflammasome-related proteins were significantly dysregulated in the cytosol of neutrophils as well as the serum from GPA patients.

CONCLUSION

Our data suggests that ROS production and regulation of the inflammasome in neutrophils from patients with GPA are disturbed and may be a potential therapeutic target.

CLINICAL TRIAL REGISTRATION NUMBER

NCT01862068, clinicaltrials.gov, https://www.clinicaltrials.gov.

Heart and systemic sclerosis-findings from a national cohort study

OBJECTIVES

Heart involvement is one of the leading causes of death in systemic sclerosis (SSc). The prevalence of SSc-related cardiac involvement is poorly known. Our objective was to investigate the prevalence and prognosis burden of different heart diseases in a nationwide cohort of patients with SSc.

METHODS

We used data from a multicentric prospective study using the French SSc national database. Focusing on SSc-related cardiac involvement, we aimed to determine its incidence and risk factors.

RESULTS

Over the 3528 patients with SSc 312 (10.9%) had SSc-related cardiac involvement at baseline. They tended to have a diffuse SSc subtype more frequently, more severe clinical features, and presented more cardiovascular risk factors. From the 1646 patients available for follow-up analysis, SSc-related cardiac involvement was associated with an increased risk of death. There was no significant difference in overall survival between SSc-related cardiac involvement, ischaemic heart disease or pulmonary arterial hypertension. Regarding survival analysis, 98 patients developed SSc-related cardiac involvement at five years (5-year event rate: 11.15%). Regarding reduced LVEF < 50% and left ventricular diastolic dysfunction, the 5-year event rate was 2.49% and 5.84% respectively. Pericarditis cumulative incidence at five years was 3%. Diffuse SSc subtype was a risk factor for SSc-related cardiac involvement and pericarditis. Female sex was associated with less left ventricular diastolic dysfunction incidence.

CONCLUSIONS

Our results describe the incidence and prognostic burden of SSc-related cardiac involvement at a large scale, with gender and diffuse SSc subtype as risk factors. Further analyses should assess the potential impact of treatment on these various cardiac outcomes.

Increased neopterin in cerebrospinal fluid in active adult neurohistiocytosis

Diagnosis of neuro-histiocytosis is challenging and relies on clinical presentation, imaging, and cerebrospinal fluid (CSF) analysis to exclude differential diagnoses. Brain biopsy remains the gold standard for accurate diagnosis, but it is rarely performed because of the risk of the procedure and the low rentability in neurodegenerative presentation. Therefore, there is an unmet need to identify a specific biomarker for diagnosing neurohistiocytosis in adults. Because microglia (brain macrophages) is involved in the pathogenesis of neurohistiocytosis and produces neopterin secondary to aggression, the purpose of our study was to evaluate the value of the CSF neopterin levels for the diagnosis of active neurohistiocytosis. Of the 21 adult patients with histiocytosis, four patients had clinical symptoms compatible with neurohistiocytosis. In the two patients with a confirmed diagnosis of neurohistiocytosis, CSF neopterin levels were elevated as well as IL-6 and IL-10 levels. In contrast, the two other patients in whom the diagnosis of neurohistiocytosis was infirmed and all other patients with histiocytosis without active neurological disease involvement had normal CSF neopterin levels. In summary, increased CSF neopterin concentration represented a valuable tool for diagnosing active neuro-histiocytosis in adults with histiocytic neoplasms in this preliminary study.

Impact of BRAFV600E mutation on aggressiveness and outcomes in adult clonal histiocytosis

Histiocytoses encompass a wide spectrum of diseases, all characterized by tissue infiltration by CD68+ histiocytes. Most adult histiocytoses are considered clonal diseases because they highlight recurrent somatic mutations in the MAP-kinase pathway gene, primarily BRAF. The presence of BRAF mutation is associated with widespread disease in children with Langerhans cell histiocytosis (LCH) or cardiovascular/neurological involvement in Erdheim-Chester disease (ECD). Nevertheless, few data are available on adult clonal histiocytosis. This is why we have conducted a retrospective study of all patients with clonal histiocytosis in our institution and present the data according to the presence of BRAF mutation. Among 27 adult patients (10 ECD, 10 LCH, 5 Rosai-Dorfman disease (RDD), and 3 mixed ECD/LCH), 11 (39%) have BRAF mutation with gain of function (n = 9) and deletion (n = 2). Those patients had frequent multicentric disease with risk organ involvement, especially the brain and cardiovascular system. They had frequent associated myeloid neoplasms (mostly chronic myelomonocytic leukemia) and received more frequently targeted therapy as the front-line therapy. Nevertheless, its presence did not affect the overall survival or relapse-free survival probably due to the emergence of efficient therapies. To conclude, rapid and accurate molecular establishment in adult clonal histiocytoses is crucial because BRAFV600E mutation correlates with multicentric disease with organ involvement and incomplete metabolic response.

Mouth opening in systemic sclerosis: A longitudinal analysis from the French National Cohort Study

BACKGROUND

Few studies have evaluated mouth opening (MO) in systemic sclerosis (SSc). None have studied MO trajectories.

OBJECTIVE

To study MO trajectories in SSc.

METHODS

This multicentre study included patients enrolled in the French national SSc cohort with at least one MO assessment, described patients based on MO baseline measure, modeled MO trajectories, and associated MO measures with SSc prognosis.

RESULTS

We included 1101 patients. Baseline MO was associated with disease severity. On Kaplan-Meier analysis, MO < 30 mm was associated with worse 30-year-survival (p<0.01) and risk of pulmonary arterial hypertension (p<0.05). Individual MO trajectories were heterogenous among patients. The best model of MO trajectories according to latent-process mixed modeling showed that 88.8% patients had a stable MO trajectory and clustered patients into 3 groups that predicted SSc survival (p<0.05) and interstitial lung disease (ILD) occurrence (p<0.05). The model highlighted a cluster of 9.5% patients with diffuse cutaneous SSc (dcSSc) (p<0.05) and high but decreasing MO over 1 year (p<0.0001) who were at increased risk of poor survival and ILD.

CONCLUSION

MO, which is a simple and reliable measure, could be used to predict disease severity and survival in SSc. Although MO remained stable in most SSc patients, dcSSc patients with high but decreasing MO were at risk of poor survival and ILD. This article is protected by copyright. All rights reserved.

Prolonged response after TPO-RA discontinuation in primary ITP: results of a prospective multicenter study

Sustained response off treatment (SROT) after thrombopoietin receptor agonist (TPO-RA) discontinuation has been reported in immune thrombocytopenia (ITP). This prospective multicenter interventional study enrolled adults with persistent or chronic primary ITP and complete response (CR) on TPO-RAs. The primary end point was the proportion of patients achieving SROT (platelet count >30 × 109/L and no bleeding) at week 24 (W24) with no other ITP-specific medications. Secondary end points included the proportion of sustained CR off-treatment (SCROT, platelet count >100 × 109/L and no bleeding) and SROT at W52, bleeding events, and pattern of response to a new course of TPO-RAs. We included 48 patients with a median age of 58.5 years; 30 of 48 had chronic ITP at TPO-RA initiation. In the intention-to-treat analysis, 27 of 48 achieved SROT, 15 of 48 achieved SCROT at W24; 25 of 48 achieved SROT, and 14 of 48 achieved SCROT at W52. No severe bleeding episode occurred in patients who relapsed. Among patients rechallenged with TPO-RA, 11 of 12 achieved CR. We found no significant clinical predictors of SROT at W24. Single-cell RNA sequencing revealed enrichment of a tumor necrosis factor α signaling via NF-κB signature in CD8+ T cells of patients with no sustained response after TPO-RA discontinuation, which was further confirmed by a significant overexpression of CD69 on CD8+ T cells at baseline in these patients as compared with those achieving SCROT/SROT. Our results strongly support a strategy based on progressive tapering and discontinuation of TPO-RAs for patients with chronic ITP who achieved a stable CR on treatment. This trial was registered at www.clinicaltrials.gov as #NCT03119974.

Nephrotic syndrome and acute coronary syndrome in children, teenagers and young adults: Systematic literature review

Myocardial infarction is rare in children, teenagers and young adults (aged<20 years). The most common aetiologies identified include Kawasaki disease, familial hypercholesterolaemia, collagen vascular disease-induced coronary arteritis, substance abuse (cocaine, glue sniffing), trauma, complications of congenital heart disease surgery, genetic disorders (such as progeria), coronary artery embolism, occult malignancy and several other rare conditions. Nephrotic syndrome is a very rare cause of myocardial infarction, but it is probably underestimated. The purpose of this review was to determine the current state of knowledge on acute coronary syndrome related to nephrotic syndrome. We thus performed a comprehensive structured literature search of the Medline database for articles published between January 1st, 1969 and December 31st, 2021. Myocardial infarction in young adults can be broadly divided into two groups: cases of angiographically normal coronary arteries; and cases of coronary artery disease of varying aetiology. There are several possible mechanisms underlying the association between acute coronary syndrome and nephrotic syndrome: (1) coronary thrombosis related to hypercoagulability and/or platelet hyperactivity; (2) atherosclerosis related to hyperlipidaemia; and (3) drug treatment. All of these mechanisms must be evaluated systematically in the acute phase of disease because they evolve rapidly with the treatment of nephrotic syndrome. In this review, we propose a decision algorithm for the management of acute coronary syndrome in the context of nephrotic syndrome. The final part of the review presents the short- and medium-term therapeutic strategies available. Thromboembolism related to nephrotic syndrome is a rare non-atherosclerotic cause of acute coronary syndrome, and prospective studies are needed to evaluate a systematic approach with personalized therapeutic strategies.

[Diagnosis of giant cell arteritis]

DIAGNOSIS OF GIANT CELL ARTERITIS. The diagnosis of giant cell arteritis (GCA) must be made promptly in order to initiate appropriate treatment aimed at relieving symptoms and avoiding ischemic complications, particularly visual ones. The diagnosis of GCA is based on the occurrence, in a patient over 50, of clinical signs of GCA, primarily recent headaches, or polymyalgia rheumatica, as «evidence» of large-vessel vasculitis, which is provided by histological analysis of an arterial fragment, usually the temporal artery, or by imaging of the cephalic arteries, the aorta and/ or its main branches by Doppler US scan, angio-CT, 18fluorodeoxyglucose PET scan or more rarely by MRI angiography. In addition, in more than 95% of cases, patients have an elevation in markers of inflammatory syndrome. This is less marked in the case of visual or neurological ischemic complications. Two main GCA phenotypes can be distinguished: on the one hand, cephalic GCA, in which cephalic vessel involvement predominates and which identifies patients at the greatest risk of ischemic complications; on the other hand, extracephalic GCA concerns younger patients with a lower ischemic risk but with more aortic complications and more frequent relapses. The establishment «fast track» type structures in specialized centers allows for rapid management in order to identify patients to be treated in order to avoid ischemic complications and to quickly perform the necessary examinations to confirm the diagnosis and ensure that the patient receives appropriate management.

[Epidemiology and pathophysiology of giant cell arteritis]

EPIDEMIOLOGY AND PATHOPHYSIOLOGY OF GIANT CELL ARTERITIS. Giant cell arteritis (GCA) is a granulomatous vasculitis. It affects patients over 50 years of age, predominantly women. The pathophysiology of GCA involves genetic and environmental factors leading to the development of inflammation and subsequent large artery wall remodelling, the mechanisms of which are increasingly understood. The process is thought to begin with the activation of dendritic cells in the vessel wall. These then recruit and activate CD4 T cells, inducing their proliferation and polarisation into Th1 and Th17 cells, which produce interferon-gamma (IFN-γ) and interleukin-17 (IL-17) respectively. IFN-γ activates vascular smooth muscle cells, which produce chemokines that induce the recruitment of other mononuclear cells (CD4 and CD8 T cells and monocytes). This inflammatory infiltrate, the differentiation of monocytes into macrophages induce the production of other mediators that cause remodeling of the vascular wall based on destruction of the arterial wall, neoangiogenesis and intimal hyperplasia. This remodelling leads to the ischaemic manifestations of GCA by causing stenosis or even occlusion of the affected vessels. More recently, mechanisms have been identified that allow the perpetuation of inflammation and vascular remodelling, explaining the chronic evolution of GCA.

[Treatment of giant cell arteritis]

TREATMENT OF GIANT CELL ARTERITIS. The treatment of giant cell arteritis (GCA) is based on glucocorticoids. This treatment significantly reduces the risk of ischemic complications, especially those of a visual nature, rapidly relieves the symptoms of the disease, and eliminates the inflammatory syndrome. The diagnosis of GCA must be able to question if corticosteroid therapy is ineffective. Once the symptoms have resolved and the inflammatory syndrome has normalized, glucocorticosteroids are tapered very gradually. The goal is to discontinue glucocorticosteroids in 12 to 18 months. Nearly half of patients experience flares during the glucocorticoid taper. These are usually benign, not visually life-threatening, and easily controlled by increasing glucocorticoids. However, these relapses contribute to prolonging the treatment duration and thus the cumulative dose of glucocorticoids received by patients, which leads to the occurrence of adverse effects of glucocorticoids in almost all patients. For this reason, it is sometimes necessary to prescribe glucocorticoid-sparing treatments, particularly methotrexate and tocilizumab. The efficacy of these treatments and others in development is essential and to be discussed. In addition, the management of patients with GCA should include preventive measures to reduce cardiovascular, infectious and osteoporosis risks.

Human monocyte-derived suppressive cells (HuMoSC) for cell therapy in giant cell arteritis

Introduction

The pathogenesis of Giant Cell Arteritis (GCA) relies on vascular inflammation and vascular remodeling, the latter being poorly controlled by current treatments.

Methods

This study aimed to evaluate the effect of a novel cell therapy, Human Monocyte-derived Suppressor Cells (HuMoSC), on inflammation and vascular remodeling to improve GCA treatment. Fragments of temporal arteries (TAs) from GCA patients were cultured alone or in the presence of HuMoSCs or their supernatant. After five days, mRNA expression was measured in the TAs and proteins were measured in culture supernatant. The proliferation and migration capacity of vascular smooth muscle cells (VSMCs) were also analyzed with or without HuMoSC supernatant.

Results

Transcripts of genes implicated in vascular inflammation (CCL2, CCR2, CXCR3, HLADR), vascular remodeling (PDGF, PDGFR), angiogenesis (VEGF) and extracellular matrix composition (COL1A1, COL3A1 and FN1) were decreased in arteries treated with HuMoSCs or their supernatant. Likewise, concentrations of collagen-1 and VEGF were lower in the supernatants of TAs cultivated with HuMoSCs. In the presence of PDGF, the proliferation and migration of VSMCs were both decreased after treatment with HuMoSC supernatant. Study of the PDGF pathway suggests that HuMoSCs act through inhibition of mTOR activity. Finally, we show that HuMoSCs could be recruited in the arterial wall through the implication of CCR5 and its ligands.

Conclusion

Altogether, our results suggest that HuMoSCs or their supernatant could be useful to decrease vascular in flammation and remodeling in GCA, the latter being an unmet need in GCA treatment.

Diagnostics différentiels de la maladie de Castleman

Clinicians are sometimes confronted with the diagnostic difficulties of the idiopathic form of Castleman's Disease (iMCD). As this review reports with demonstrative clinical cases, iMCD can mimic various serious systemic pathologies such as certain autoimmune diseases, Still's disease, POEMS syndrome, and malignant lymphoproliferations, sharing a very similar histology and identical symptoms. To make a diagnosis of iMCD, the clinician must eliminate all the pathologies mentioned above, but he must first think of it and evoke this diagnosis of rare disease before the first symptoms but also know how to evoke this diagnosis again even after several years of evolution of a disease like those mentioned above whose evolution is not favorable. © 2022 Published by Elsevier Masson SAS on behalf of Société nationale française de médecine interne (SNFMI).

Rituximab vs Cyclophosphamide Induction Therapy for Patients With Granulomatosis With Polyangiitis

IMPORTANCE

Results of randomized clinical trials have demonstrated rituximab's noninferiority to cyclophosphamide as induction therapy for antineutrophil cytoplasm antibody (ANCA)-associated vasculitides (AAV), with neither treatment having a specific advantage for granulomatosis with polyangiitis (GPA). However, post hoc analysis results have suggested that rituximab might be more effective than cyclophosphamide in inducing remission in patients with proteinase 3-positive AAV.

OBJECTIVE

To compare the effectiveness of rituximab and cyclophosphamide in inducing GPA remission in a large population of unselected patients.

DESIGN, SETTING, AND PARTICIPANTS

This comparative effectiveness study used multicenter target trial emulation observational data from 32 French hospitals in the French Vasculitis Study Group Registry. Groups were determined according to treatments received, without any intervention from the investigators. Inverse probability of treatment weighting was used to correct for baseline imbalance between groups. Participants included patients with newly diagnosed or relapsing GPA who satisfied American College of Rheumatology classification criteria and/or Chapel Hill Consensus Conference nomenclature. Data were analyzed from October 1, 2021, to May 31, 2022.

EXPOSURES

At least 1 infusion of rituximab or cyclophosphamide for induction therapy between April 1, 2008, and April 1, 2018.

MAIN OUTCOMES AND MEASURES

The primary outcome was remission rate at month 6 (±2 months), with remission defined as a Birmingham Vasculitis Activity Score (BVAS) of 0 and prednisone dose of 10 mg/d or less. The BVAS is a validated tool for small-vessel vasculitis and used to assess the level of disease activity, with a numerical weight attached to each involved organ system. The BVAS has a range of 0 to 63 points; a score of 0 indicates no disease activity. Subgroup analyses included the primary outcome for patients with a new diagnosis, for most recently treated patients, and for patients with myeloperoxidase-ANCA positivity.

RESULTS

Among 194 patients with GPA included in the analysis (mean [SD] age, 54 [15] years; 110 men [56.7%]), 165 (85.1%) had a new diagnosis, and 147 of 182 with data available (80.8%) had proteinase 3-ANCA positivity. Sixty-one patients received rituximab and 133 received cyclophosphamide for induction therapy. In the weighted analysis, the primary outcome was reached for 73.1% of patients receiving rituximab vs 40.1% receiving cyclophosphamide (relative risk [RR], 1.82 [95% CI, 1.22-2.73]; risk difference, 33.0% [95% CI, 12.2%-53.8%]; E value for RR, 3.05). Similar results were observed in the subgroup of patients with newly diagnosed GPA and those with a more recent treatment. In the subset of 27 patients with myeloperoxidase-ANCA-positive GPA, 8 of 10 rituximab recipients and 8 of 17 cyclophosphamide recipients met the primary end point (unweighted RR, 1.73 [95% CI, 0.96-3.11]).

CONCLUSIONS AND RELEVANCE

In this comparativeness effectiveness study using clinical data, rituximab induction therapy for GPA was more frequently associated with remission than cyclophosphamide. These results inform clinical decision-making concerning the choice of remission induction therapy for this subset of patients with AAV.

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.

T-cell immune response predicts the risk of critical SARS-Cov2 infection in hospitalized COVID-19 patients

INTRODUCTION

This study aimed to identify markers of disease worsening in patients hospitalized for SARS-Cov2 infection.

PATIENTS AND METHODS

Patients hospitalized for severe recent-onset (<1 week) SARS-Cov2 infection were prospectively included. The percentage of T-cell subsets and plasma IL-6 at admission (before any steroid therapy) were compared between patients who progressed to a critical infection and those who did not.

RESULTS

Thirty-seven patients (18 men, 19 women) were included; 11 (30%) progressed to critical infection. At admission, the critical infection patients were older (P = 0.021), had higher creatinine levels (P = 0.003), and decreased percentages of circulating B cells (P = 0.04), T cells (P = 0.009), and CD4+ T cells (P = 0.004) than those with a favorable course. Among T cell subsets, there was no significant difference between the two groups except for the percentage of Th17 cells, which was two-fold higher in patients who progressed to critical infection (P = 0.028). Plasma IL-6 at admission was also higher in this group (P = 0.018). In multivariate analysis, the percentage of circulating Th17 cells at admission was the only variable associated with higher risk of progression to critical SARS-Cov2 infection (P = 0.021).

CONCLUSION

This study suggests that an elevated percentage of Th17 cells in patients hospitalized for SARS-Cov2 infection is associated with an increased risk of progression to critical disease. If these data are confirmed in a larger study, this marker could be used to better target the population of patients in whom tocilizumab could decrease the risk of progression to critical COVID-19.

Dramatic Efficacy of Interferon and Vemurafenib on Psychiatric Symptoms Revealing BRAFV600E -Mutated Erdheim-Chester Disease: A Case Report

Erdheim–Chester disease (ECD) is a rare condition with underestimated neurological involvement. Mild psychiatric symptoms such as mood swings have been rarely described in the clinical spectrum of neuro-ECD. We here describe the first patient with psychiatric manifestations of delirium revealing ECD with neurological involvement with favorable evolution under interferon followed by BRAF inhibitor monotherapy. An 81-year-old woman was referred to the hospital because of delirium and severe cognitive impairment associated with a cerebellar syndrome. Brain magnetic resonance imaging showed “FLAIR-changes” lesions in the pons and upper cerebellum peduncles. Blood and cerebrospinal fluid (CSF) analyses showed normal results except for an elevated neopterin level in the CSF. Whole-body CT scan (¹⁸FDG-PET) showed peri-nephric fat infiltration and aorta adventitia sheathing with radiotracer uptake in the pons, vessels, peri-nephric fat, and bone lesions, which was characteristic of ECD. The diagnosis was confirmed on perirenal tissue biopsy, which also showed a BRAF^V600E mutation. Treatment with interferon resulted in the resolution of delirium, and treatment with BRAF inhibitor subsequently resulted in a partial remission of all active sites. This case highlights that delirium can be the first manifestation of neurodegenerative ECD. ECD should be screened in unexplained psychiatric features as interferon and targeted therapy appear to be effective in this situation.

PET/CT of cranial arteries for a sensitive diagnosis of giant cell arteritis

OBJECTIVES

To investigate the performance of cranial PET/CT for the diagnosis of giant cell arteritis (GCA).

METHODS

All patients with a suspected diagnosis of GCA were prospectively enrolled in this study and had a digital PET/CT with evaluation of cranial arteries if they had not started glucocorticoids more than 72 hours previously. The diagnosis of GCA was retained after at least 6 months of follow-up if no other diagnosis was considered by the clinician and the patient went into remission after at least 6 consecutive months of treatment. Cranial PET/CT was considered positive if at least one arterial segment showed hypermetabolism similar to or greater than liver uptake.

RESULTS

For cranial PET/CT, sensitivity (Se), specificity (Sp), positive predictive value (PPV) and negative predictive value (NPV) were 73.3%, 97.2%, 91.7% and 89.7%, respectively. For extracranial PET/CT, diagnostic performance was lower (Se = 66.7%, Sp = 80.6%, PPV = 58.8%, NPV = 85.3%). The combination of cranial and extracranial PET/CT improved overall sensitivity (Se = 80%) and NPV (NPV = 90.3%) while decreasing overall specificity (Sp = 77.8%) and PPV (PPV = 60%).

CONCLUSION

Cranial PET/CT can be easily combined with extracranial PET/CT with a limited increase in examination time. Combined cranial and extracranial PET/CT showed very high diagnostic accuracy for the diagnosis of GCA.

TRIAL REGISTRATION

ClinicalTrials.gov, https://clinicaltrials.gov, NCT05246540.

POS0494 ARTERIAL WALL DENDRITIC CELLS IN GIANT CELL ARTERITIS (GCA) AND POLYMYALGIA RHEUMATICA (PMR)

Background

Polymyalgia rheumatica (PMR) is an inflammatory rheumatic disease (1) associated in 16 to 21% of cases with giant cell arteritis (GCA). The association of these two conditions raises the question of a pathophysiological continuum between PMR and GCA. An early study reported mature arterial wall dendritic cells (DC) in patients with GCA or PMR leading, during GCA, to CD4+ T cell recruitment and the development of vasculitis (2). However, these data have never been confirmed in other studies. There are 3 main types of DC: plasmacytoid DC (expressing CD123), conventional DC (cDC) expressing CD141 (cDC1) or CD1c (cDC2) and monocyte-derived DC (mo-DC) expressing CD14.

Objectives

The aim of this study was to describe the arterial wall infiltrating DCs, their phenotype and maturation state, during PMR and GCA.

Methods

Using temporal artery biopsies (TAB) from patients with PMR, GCA and healthy controls, the level of expression of CD11c, CD83, CCR7, CCR6, CD1c, CCL18, CCL19, CCL20, CCL21, GM-CSF, CD3, CD68 genes was assessed by RT-PCR. Expression of markers of DC lineage (CD209), DC maturation state (CD83 and CCR7) and DC origin (CD14, CD68, CD1c, CD141) were studied by confocal microscopy.

Results

Fourty-one patients were included (14 GCA, 16 PMR, 11 controls). Within the arterial wall, DCs were identified in GCA patients, with a mature DC phenotype (CD209+CD83+CCR7+). DC were present in all three layers of the arterial wall and also expressed CD14 and often CD68 but neither CD1c nor CD141, which could be explained by a monocytic/macrophage origin. TAB from GCA patients were characterized by a high level of expression of CD83, CCR7, CCR6, CCL18, CCL19, CCL20, CD11c, GM-CSF, CD3 and CD68 gene. This expression was significantly higher (p<0.05) compared to the control and PMR groups.

Confocal microscopy analyses of arteries from the PMR and controls did not detect the presence of DCs into the arterial wall. In addition, level of expression of CD83, CCR7, CCL18, CCL19, CCL21 and CD68 genes in temporal arteries was comparable between PMR and healthy controls.

Conclusion

This work confirms the presence of mature CD209+CD83+CCR7+ DCs within the arterial wall in GCA. The phenotype of these DCs mainly fits with DC of monocytic origin (mo-DCs). However, both by RT-PCR and confocal microscopy, we did not identify DCs in the arterial wall of PMR patients. This discrepancy with previous work (3) could be explained by a better diagnosis of GCA in PMR patients since the development of imaging techniques.

References

[1]Weyand CM, Goronzy JJ. Giant-Cell Arteritis and Polymyalgia Rheumatica. N Engl J Med. 2014;371:50-7.

[2]Samson M, Corbera-Bellalta M, Audia S, Planas-Rigol E, Martin L, Cid MC, et al. Recent advances in our understanding of giant cell arteritis pathogenesis. Autoimmun Rev. 2017;16:833-44.

[3]Ma-Krupa W, Jeon M-S, Spoerl S, Tedder TF, Goronzy JJ, Weyand CM. Activation of Arterial Wall Dendritic Cells and Breakdown of Self-tolerance in Giant Cell Arteritis. J Exp Med. 2004;199:173-83.

Disclosure of Interests

None declared.

L’augmentation du pourcentage de lymphocytes Th17 est associée à un risque d’évolution vers une forme grave d’infection à SARS-CoV-2

Introduction

Depuis décembre 2019, plus de 20 millions de français ont été infectés par le SARS-CoV-2 et plus de 130 000 en sont décédés. La physiopathologie de cette infection n’est pas totalement élucidée. Il a été démontré qu’elle provoquait une importante sécrétion de cytokines pro-inflammatoires, en particulier d’interleukine-6 (IL-6) [1]. Lorsque les patients infectés sont hospitalisés, ils reçoivent généralement de la dexaméthasone et parfois un traitement anti-infectieux. Si la maladie s’aggrave, le tocilizumab peut être ajouté [2]. Actuellement, seule l’évolution clinique incite à débuter le tocilizumab, mais parfois trop tardivement. Il manque aux cliniciens un marqueur précoce leur permettant de prédire le risque d’aggravation de la maladie. Cette étude, menée chez des patients hospitalisés pour infection à SARS-CoV-2 pendant la 2^e vague, avait pour objectif de rechercher un marqueur d’aggravation de la maladie en comparant la réponse lymphocytaire entre les patients évoluant vers une forme grave et les autres.

Patients et méthodes

Les patients hospitalisés pour infection à SARS-CoV-2 prouvée par RT-PCR datant de moins d’une semaine ont été inclus prospectivement dans cette étude monocentrique. Une infection grave était définie par un transfert en soins intensifs, en réanimation ou le décès. Des prélèvements sanguins ont été obtenus à l’admission à l’hôpital et avant de débuter la corticothérapie afin d’étudier les sous-populations lymphocytaires par cytométrie en flux et doser l’IL-6 plasmatique par immunofluorimétrie. Les données sont exprimées en nombre (%) ou médiane (espace inter-quartile).

Résultats

De septembre à décembre 2020, 37 patients (18 hommes, 19 femmes) hospitalisés pour infection à SARS-Cov2 ont été inclus : âge = 81,7 (70,3–87,5) ans, IMC = 25,7 (23,7–29) kg/m², hypertension artérielle (54 %), diabète (24 %), dyslipidémie (35 %), tabagisme (24 %), cardiopathie ischémique (8 %), maladie cérébrovasculaire (11 %). La durée de suivi était de 10 (8–15) jours. Parmi les 37 patients inclus, 11 (30 %) ont présenté une infection à SARS-CoV-2 grave dont 4 transferts en réanimation et 8 décès. À l’admission, les patients ayant une infection évoluant vers une forme grave étaient plus âgés (p = 0,021), avaient une créatininémie plus élevée (p = 0,003) et une diminution du pourcentage de lymphocytes B (p = 0,04), de lymphocytes T (p = 0,009) et de lymphocytes T CD4+ (p = 0,004) circulants parmi les lymphocytes totaux comparativement aux patients dont l’évolution était favorable. Parmi les sous-populations lymphocytaires T étudiées (mémoires, naïfs, Th1, Th2, Th17, Treg, Tc1, Tc17, T CD8 cytotoxiques), il n’y avait pas de différence significative entre les deux groupes en dehors du pourcentage de lymphocytes Th17 à l’admission qui était deux fois plus élevé chez les patients dont l’infection évoluait vers une forme grave (0,44 vs 0,23 % des LT CD4 totaux ; p = 0,028). Chez les patients ayant une infection évoluant vers une forme grave, l’IL-6 plasmatique à l’admission était plus élevée (39 vs 13,1 pg/mL ; p = 0,018) et la CRP à l’admission avait tendance à être plus élevée sans atteindre le seuil de significativité (58 vs 18,5 mg/L ; p = 0,17). En analyse multivariée (régression logistique binaire comprenant les variables : âge, créatininémie, CRP, hémoglobine, lymphocytes T CD4, Th17, Treg activés (CD4 + CD45RA-FoxP3high), lymphocytes B, IL-6 sérique), la seule variable associée au risque d’évolution vers une forme grave de l’infection était le pourcentage de lymphocytes Th17 circulants (p = 0,034). L’aire sous la courbe de la courbe ROC évaluant la sensibilité et la spécificité du pourcentage de lymphocytes Th17 pour prédire une forme grave d’infection à SARS-CoV-2 chez un patient hospitalisé était de 0,75 (intervalle de confiance à 95 % : 0,56–0,95). Enfin, le fait d’avoir un pourcentage de lymphocytes Th17 > 0,435 % des lymphocytes T CD4 totaux au moment de l’admission en hospitalisation était associé à une moins bonne survie (p = 0,024).

Conclusion

Cette étude suggère qu’une élévation du pourcentage de lymphocytes Th17 chez des patients hospitalisés pour infection à SARS-CoV-2 augmente significativement le risque d’évolution vers une forme grave de la maladie. Ce résultat est cohérent avec le fait qu’il a été démontré que le tocilizumab, qui est efficace dans le traitement des formes graves de COVID-19 [2], inhibe la réponse lymphocytaire Th17 [3]. Ces données méritent d’être confirmées chez un plus grand nombre de patients afin de confirmer ce résultat car cette mesure pourrait permettre de mieux cibler la population de patients à qui proposer précocement un traitement par tocilizumab pour diminuer le risque d’évolution vers une forme grave d’infection à SARS-CoV-2.

POS0252 MYOFIBROBLASTS MAINTAIN Th1 and Tc1 POLARIZATIONS IN GIANT CELL ARTERITIS

Background

Giant cell arteritis (GCA) is a large-vessel vasculitis mainly involving the aorta and cranial arteries. It is the most frequent vasculitis in adults over 50 years. When they are stimulated by interferon-gamma (IFN-γ), vascular smooth muscle cells (VSMC) contribute to GCA pathogenesis by producing chemokines triggering the recruitment of pro-inflammatory T cells and monocytes (1).

Objectives

Current knowledge about the interaction between resident cells of the vascular wall (VSMC, myofibroblasts [MF]) and immune cells is limited. The aim of our research was to better characterize the interactions between VSMC, MF and T cells in GCA.

Methods

Fresh fragments of temporal artery biopsies (TAB) performed at Dijon university hospital (France) were prospectively sent to our research unit. Fresh sections of positive and negative TAB were fixed and embedded in optimal cutting temperature OCT and stored at -80°C. Then, cryostat sections were fixed, permeabilized, blocked and incubated with primary antibodies (anti-alpha smooth muscle actin [α-SMA], anti-myosin heavy chain 11 [MHC11], anti-Desmin, anti CD90, anti-CD45, anti-HLA-DR, anti-phospho STAT1 [pSTAT1] and anti-pSTAT3) and secondary antibodies for confocal microscopy analyses. Fresh sections of healthy TAB were embedded in MATRIGEL and covered by DMEM to obtain vascular cells in culture. Cells were treated with trypsina-EDTA between each passage. Vascular cells were used after 4-7 doubling passages. Cells were analyzed by immunofluorescence, flow cytometry and RT-PCR and their proliferation was evaluated by impedancemetry (iCELLigence system). Peripheral blood mononuclear cells (PBMC) and vascular cells thus obtained were co-cultured for 7 days in different conditions. Vascular cells were cultured in the presence or absence of IFN-γ and tumor necrosis factor alpha (TNF-α) or interleukin-6 (IL-6) and soluble receptor of IL-6 for 72 hours. When cells reached confluence, they were cultured alone or with allogenic PBMC activated with anti-CD3/CD28 microbeads. After 7 days of culture, cells were separated with a treatment with EDTA and studied by flow cytometry.

Results

Confocal microscopy analyses of GCA arteries showed that neointima was mainly composed of myofibroblasts (MF) (α-SMA+Desmin+MHC11lowCD90+) in contact with CD45+ cells and that MF expressed HLA-DR, the phosphorylated form of STAT1 (pSTAT1) and in a lesser extent pSTAT3, strongly suggesting the activation of the IFN-γ signaling pathway rather than the IL-6 pathway. The phenotype of cultured vascular cells isolated from fresh TAB was consistent with MF. When MF were exposed to IFN-γ and TNF-α in vitro, their proliferation capacity decreased and their levels of expression of HLA-DR and CD86 increased (median fluorescence intensity [MFI] from 0 to 57 [p=0.03] and from 34 to 103 [p=0.03], respectively). In addition, co-cultures of MF and activated PBMC revealed that MF maintained the polarization of T cells into Th1 and Tc1 cells (p≤0.001) and to a lesser extent into Th17 and Tc17 cells (p=0.03). This effect was even more significant when MF were previously exposed to IFN-γ and TNF-α but not when they were exposed to IL-6.

Conclusion

Our results show that myofibroblasts are present in the neointima of GCA patients and that these MF activate signaling pathways indicative of IFN-γ exposure. Moreover, these MF, especially when exposed to IFN-γ, maintain the polarization of T cells into Th1 and Tc1 cells, which contributes to amplify the production of IFN-γ and thus initiate a pro-inflammatory amplification loop that likely participates in vascular inflammation and remodelling.

References

[1]Corbera-Bellalta M, Planas-Rigol E, Lozano E, Terrades-Garcia N, Alba MA, Prieto-Gonzalez S, et al. Blocking interferon gamma reduces expression of chemokines CXCL9, CXCL10 and CXCL11 and decreases macrophage infiltration in ex vivo cultured arteries from patients with giant cell arteritis. Ann Rheum Dis 2016;75:1177-86.

Disclosure of Interests

None declared

Human Monocyte-Derived Suppressor Cell Supernatant Induces Immunoregulatory Effects and Mitigates xenoGvHD

Recently developed cell-based therapies have shown potential for graft-versus-host disease (GvHD) mitigation. Our team previously developed a protocol to generate human monocyte-derived suppressor Cells (HuMoSC), a subpopulation of CD33+ suppressor cells of monocytic origin. CD33+HuMoSC successfully reduced xenoGvHD severity in NOD/SCID/IL-2Rγc^-/- (NSG) mice. While CD33+ HuMoSC culture supernatant inhibits T cell activation and proliferation, the recovery of CD33+ HuMoSC immunosuppressive cells and the subsequent production of their supernatant is limited. An attractive solution would be to use both the CD33+ and the large number of CD14+ cells derived from our protocol. Here, we assessed the immunoregulatory properties of the CD14+HuMoSC supernatant and demonstrated that it inhibited both CD4 and CD8 T cell proliferation and decreased CD8 cytotoxicity. In vivo, injection of CD14+HuMoSC supernatant reduced xenoGvHD in NSG mice. Furthermore, CD14+HuMoSC supernatant maintained its immunoregulatory properties in an inflammatory environment. Proteomic and multiplex analyses revealed the presence of immunosuppressive proteins such as GPNMB, galectin-3 and IL-1R(A) Finally, CD14+HuMoSC supernatant can be produced using good manufacturing practices and be used as complement to current immunosuppressive drugs. CD14+HuMoSC supernatant is thus a promising therapy for preventing GvHD.