Incidence et caractéristiques des hémopathies malignes au cours de l’artérite à cellules géantes

Introduction L’arterite a cellules geantes (ACG) est une vascularite du sujet âge au cours de laquelle les cellules mononucleees jouent un role physiopathologique majeur. L’hematopoiese clonale est un phenomene dont la frequence augmente egalement avec l’âge et qui conduit a l’apparition de mutations responsables de la survenue d’hemopathies malignes (HM) ou de mutations des cellules effectrices de l’immunite responsables de pathologies inflammatoires. Notre hypothese est qu’il existe une association specifique entre certaines HM et l’ACG. Nous avons pu etudier cette hypothese en croisant les donnees du registre des hemopathies de Cote d’Or (RHEMCO) et celles de tous les laboratoires d’anat…

Ophthalmic manifestations in IgG4-related disease

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Le tocilizumab corrige le déséquilibre de la balance Th17/Treg chez les patients atteints de polyarthrite rhumatoïde

Brief Report: Inhibition of interleukin-6 function corrects Th17/Treg cell imbalance in patients with rheumatoid arthritis

OBJECTIVE: From an immunologic standpoint, the mechanisms by which treatment with tocilizumab (TCZ), a humanized anti-interleukin-6 (anti-IL-6) receptor antibody, results in improvement in rheumatoid arthritis (RA) patients are still not fully understood. In vitro studies and studies in mouse models have demonstrated the critical role of IL-6 in Th17 cell differentiation. Th17 lymphocytes have been shown to be strongly involved in RA pathogenesis, and the purpose of this study was to investigate the effect of IL-6 blockade on the balance between Th17 cells and Treg cells in patients with active RA. METHODS: Patients with active RA for whom TCZ had been prescribed by a rheumatologist were en…

Should mild hypogammaglobulinemia be managed as severe hypogammaglobulinemia? A study of 389 patients with secondary hypogammaglobulinemia.

Although secondary hypogammaglobulinemia is more frequent than primary hypogammaglobulinemia, its etiology and management are poorly described, particularly for mild hypogammaglobulinemia.This retrospective observational study included all adult patients with a gammaglobulin level6.4g/L on serum electrophoresis identified at Dijon teaching hospital between April and September 2012. Clinico-biological features, etiologies and infectious complications were collected at inclusion and compared between group 1 (gammaglobulin5g/L, severe hypogammaglobulinemia), and group 2 (gammaglobulin6.4 and ≥5g/L, mild hypogammaglobulinemia).Among the 4011 serum electrophoreses, 570 samples from 389 patients …

Modification de la réponse immunitaire au cours de la maladie de Rendu-Osler

Introduction La maladie de Rendu-Osler (MRO) est une maladie genetique vasculaire rare caracterisee par une neo-angiogenese deregulee aboutissant a des epistaxis anemiantes parfois associees a malformations arterio-veineuses (MAV) pulmonaires, hepatiques ou cerebrales. La MRO est egalement associee a une lymphopenie T predominant sur les CD4+ dont les causes et les consequences sont mal connues. L’objectif de ce travail est de decrire les polarisations lymphocytaires Th1, Th2, Th17, Th1-17 et Treg au cours de la MRO. Patients et methodes Les patients atteints de MRO confirmee genetiquement ont ete prospectivement inclus lors de leur suivi habituel. Le score de severite des epistaxis (ESS), …

Haemolytic-uraemic syndrome during severe lupus nephritis: efficacy of plasma exchange

Systemic lupus erythematosus (SLE) has been described as a cause of thrombotic microangiopathy, especially thrombotic thrombocytopenic purpura (TTP). Haemolytic-uraemic syndrome (HUS) is less frequent in SLE. We report a case of such an association during an episode of severe lupus nephritis in a young woman, who was successfully treated with steroids, cyclophosphamide and especially plasma exchange with plasma replacement. This report highlights the importance of recognising atypical HUS in SLE patients by looking for schistocytes in case of haemolytic anemia with a negative antiglobulin test, in order to begin plasma exchange.

Antiplatelet Antibodies Do Not Predict the Response to Intravenous Immunoglobulins during Immune Thrombocytopenia

Immune thrombocytopenia (ITP) is a rare autoimmune disease due to autoantibodies targeting platelet glycoproteins (GP). The mechanism of platelet destruction could differ depending on the specificity of antiplatelet antibodies: anti-GPIIb/IIIa antibodies lead to phagocytosis by splenic macrophages, in a Fc&gamma

L’augmentation de la réponse Th17 au cours de la maladie de Horton et de la PPR est liée à des modifications fonctionnelles et non quantitatives de leurs précurseurs : les lymphocytes T CD4+ CD161+

Etude physiopathologique de la réponse immunitaire au cours de la thrombopénie immunologique (purpura thrombopénique immunologique)

Immune thrombocytopenia (ITP) is an autoimmune disease responsible for a peripheral immune destruction of platelets associated with an inappropriate bone marrow production. In this work, we first review the mechanisms involved in the pathogenesis of ITP. We also focus on the T cell immune response, highlighting the key role of regulatory T cells (Treg) in peripheral tolerance. The implication of the spleen in the immune response and the effects of rituximab, a B cell depleting therapy, are discussed. Then, our results obtained from 40 ITP patients are reported. Despite the fact that CD4+CD25HighFoxp3+ circulating Treg levels are similar between patients and controls, a significant increase …

Evans’ Syndrome: From Diagnosis to Treatment

Evans’ syndrome (ES) is defined as the concomitant or sequential association of warm auto-immune haemolytic anaemia (AIHA) with immune thrombocytopenia (ITP), and less frequently autoimmune neutropenia. ES is a rare situation that represents up to 7% of AIHA and around 2% of ITP. When AIHA and ITP occurred concomitantly, the diagnosis procedure must rule out differential diagnoses such as thrombotic microangiopathies, anaemia due to bleedings complicating ITP, vitamin deficiencies, myelodysplastic syndromes, paroxysmal nocturnal haemoglobinuria, or specific conditions like HELLP when occurring during pregnancy. As for isolated auto-immune cytopenia (AIC), the determination of the primary or…

Altered distribution and function of splenic innate lymphoid cells in adult chronic immune thrombocytopenia

IF 7.607; International audience; Innate lymphoid cells (ILCs) have been characterized as innate immune cells capable to modulate the immune response in the mucosae. Human ILCs have been rarely described in secondary lymphoid organs except in tonsils. Moreover, their function and phenotype in human secondary lymphoid organs during autoimmune diseases have never been studied. We took advantage of splenectomy as a treatment of immune thrombocytopenia (ITP) to describe and compare splenic ILC from 18 ITP patients to 11 controls. We first confirmed that ILC3 represented the most abundant ILC subset in human non-inflamed spleens, accounting for 90% of total ILC, and that they were mostly constit…

Caractérisation de l’anémie hémolytique auto-immune associée aux hémopathies lymphoïdes à partir du registre des hémopathies malignes de Côte d’Or

Introduction L’anemie hemolytique auto-immune (AHAI) est une cytopenie auto-immune (CAI) caracterisee par une destruction des globules rouges par des auto-anticorps diriges contre certains de leurs antigenes de surface. Son incidence est estimee entre 1 et 3/100 000 personnes-annees (PA). Les AHAI a auto-anticorps chauds sont les plus frequentes et les formes secondaires, observees dans la moitie des cas, ont tendance a augmenter avec l’âge, notamment en association aux hemopathies malignes. Les donnees de la litterature reposent cependant sur de faibles cohortes ou des centres tertiaires, avec un possible biais de recrutement. L’objectif de notre etude est de decrire la frequence de l’AHAI…

Th1 and Th17 lymphocytes expressing CD161 are implicated in giant cell arteritis and polymyalgia rheumatica pathogenesis.

International audience; OBJECTIVE: Giant cell arteritis (GCA) is the most frequently occurring vasculitis in elderly individuals, and its pathogenesis is not fully understood. The objective of this study was to decipher the role of the major CD4+ T cell subsets in GCA and its rheumatologic form, polymyalgia rheumatica (PMR). METHODS: A prospective study of the phenotype and the function of major CD4+ T cell subsets (Th1, Th17, and Treg cells) was performed in 34 untreated patients with GCA or PMR, in comparison with 31 healthy control subjects and with the 27 treated patients who remained after the 7 others withdrew. RESULTS: Compared with control subjects, patients with GCA and patients wi…

Stroke associated with giant cell arteritis: a population-based study

Background Giant cell arteritis (GCA) is the most common vasculitis in people ≥50 years and can be associated with stroke. We aimed to evaluate the epidemiology and characteristics of stroke in patients with GCA. Methods All patients with a biopsy-proven diagnosis of GCA were identified among residents of the city of Dijon, France (152 000 inhabitants), between 2001 and 2012 using a prospective database. Among these, patients who suffered from stroke were retrieved by crossing data from the population-based Dijon Stroke Registry. Demographics and clinical features were recorded. We considered that the stroke was GCA-related if the stroke revealed GCA or occurred between the onset of symptom…

Tocilizumab en association à la prednisone au cours des 3 premiers mois de traitement de l’artérite à cellules géantes : résultats d’une étude prospective, multicentrique de phase II (PHRC National HORTOCI)

Introduction L’arterite a cellules geantes (ACG) est une vascularite des gros vaisseaux habituellement traitee par corticoides. Ce traitement est remarquablement efficace mais doit etre donne a forte dose pendant 12 a 24 mois, ce qui est responsable d’une importante morbi-mortalite dans cette population âgee. Le tocilizumab (TCZ) est un anticorps monoclonal humanise dirige contre les recepteurs (soluble et membranaire) de l’interleukine-6 (IL-6). Son efficacite a recemment ete montree au cours du traitement de l’ACG [1] . Cependant, les donnees concernant l’evolution apres l’arret du TCZ manquaient dans cet essai therapeutique. De plus, la duree optimale de ce traitement couteux n’est pas c…

Immunologic effects of rituximab on the human spleen in immune thrombocytopenia

Abstract Immune thrombocytopenia (ITP) is an autoimmune disease with a complex pathogenesis. As in many B cell–related autoimmune diseases, rituximab (RTX) has been shown to increase platelet counts in some ITP patients. From an immunologic standpoint, the mode of action of RTX and the reasons underlying its limited efficacy have yet to be elucidated. Because splenectomy is a cornerstone treatment of ITP, the immune effect of RTX on this major secondary lymphoid organ was investigated in 18 spleens removed from ITP patients who were treated or not with RTX. Spleens from ITP individuals had follicular hyperplasia consistent with secondary follicles. RTX therapy resulted in complete B-cell de…

Caractérisation de la thrombopénie immunologique associée aux hémopathies lymphoïdes à partir du registre des hémopathies malignes de Côte d’Or

Introduction Le purpura thrombopenique immunologique (PTI) est une cytopenie auto-immune (CAI) caracterisee par une diminution de la duree de vie des plaquettes liee a la fois a leur destruction peripherique par les macrophages spleniques et a un defaut de production medullaire. Son incidence est estimee entre 3 et 4/100 000 personnes-annees (PA). S’il est le plus souvent primaire, il est associe dans 15–20 % des cas a d’autres maladies auto-immunes ou a des hemopathies malignes. Pour ces dernieres, les associations les plus frequentes sont rapportees avec la leucemie lymphoide chronique (LLC), la leucemie a grands lymphocytes T granuleux (LGL) et le lymphome de Hodgkin (LH) mais les donnee…

Moving from Dermatomyositis Associated with Anti-Melanoma Differentiation-Associated Gene 5 Antibody to Anti-Melanoma Differentiation-Associated Gene 5 Syndrome

International audience

Systematic retrospective study of 64 patients with anti-Mi2 dermatomyositis: A classic skin rash with a necrotizing myositis and high risk of malignancy

T cell Polarization toward T(H)2/T(FH)2 and T(H)17/T(FH)17 in Patients with IgG4-related Disease

International audience; IgG4-related disease (IgG4-RD) is a fibro-inflammatory disorder involving virtually every organ with a risk of organ dysfunction. Despite recent studies regarding B cell and T cell compartments, the disease's pathophysiology remains poorly understood. We examined and characterized subsets of circulating lymphocytes in untreated patients with active IgG4-RD. Twenty-eight consecutive patients with biopsy-proven IgG4-RD were included in a prospective, multicentric study. Lymphocyte's subsets were analyzed by flow cytometry, with analysis of T(H)1/T(H)2/T(H)17, T-FH cells, and cytokine release by peripheral blood mononuclear cells. Results were compared to healthy contro…

Immune Thrombocytopenia: Recent Advances in Pathogenesis and Treatments

Immune thrombocytopenia (ITP) is a rare autoimmune disease due to both a peripheral destruction of platelets and an inappropriate bone marrow production. Although the primary triggering factors of ITP remain unknown, a loss of immune tolerance—mostly represented by a regulatory T-cell defect—allows T follicular helper cells to stimulate autoreactive splenic B cells that differentiate into antiplatelet antibody-producing plasma cells. Glycoprotein IIb/IIIa is the main target of antiplatelet antibodies leading to platelet phagocytosis by splenic macrophages, through interactions with Fc gamma receptors (FcγRs) and complement receptors. This allows macrophages to activate autoreactive T cells …

Efficacy and safety of dapsone as second line therapy for adult immune thrombocytopenia: A retrospective study of 42 patients.

Dapsone is recommended as a second line therapy in immune thrombocytopenia (ITP), but is underused because of its potential side effects. The medical charts of 42 ITP patients treated with dapsone (100 mg/day) were retrospectively reviewed in order to assess its efficacy and safety in daily clinical practice. The overall response rate was 54.8% (n = 22, with a complete response in 38.1%) with a median time to response of 29 days (24-41 days). Patients with complete response had shorter disease duration whereas no difference was observed between responders and non-responders regarding age, sex or previous treatments received. Importantly, after dapsone withdrawal, a sustained response was ob…

Is TNF-α really involved in giant cell arteritis pathogenesis?

Giant cell arteritis (GCA) is the most frequent vasculitis in people >50 years, and glucocorticoids (GC) remain the cornerstone of the treatment. However, this long-term treatment is responsible for numerous GC-related complications.1 Thus, reliable GC-sparing drugs need to be explored. Seror et al 2 have recently reported the inefficacy of adalimumab, a humanised anti-TNF-α therapy, as a GC-sparing drug in the treatment of GCA. These clinical results contrast with previous studies reporting a production of TNF-α by giant cells and macrophages in GCA lesions.3 However, recent advance in the knowledge of GCA pathogenesis have shown that macrophages and giant cells are not involved in the fir…

Does Tocilizumab Indeed Reduce the Frequency of Th17 Cells? Comment on the Article by Thiolat et al

Are IL-10+ regulatory Th17 cells implicated in the sustained response to glucocorticoid treatment in patients with giant cell arteritis? Comment on the paper of Espigol-Frigoleet al

We have read with interest the recently published paper of Espigol-Frigole et al 1 in which the authors confirmed that interleukin (IL)-17 is highly expressed in giant cell arteritis (GCA) lesions.1–3 They also demonstrated for the first time that IL-17 expression in temporal artery biopsies (TABs) was correlated with a better outcome. Among other interesting results, the identification of Foxp3+IL-17+ T cells by confocal microscopy in TAB made the authors to hypothesize that these cells could be induced regulatory T cells (Treg) that may facilitate the remission of the disease under steroid therapy. …

Emerging Therapies in Immune Thrombocytopenia

Immune thrombocytopenia (ITP) is a rare autoimmune disorder caused by peripheral platelet destruction and inappropriate bone marrow production. The management of ITP is based on the utilization of steroids, intravenous immunoglobulins, rituximab, thrombopoietin receptor agonists (TPO-RAs), immunosuppressants and splenectomy. Recent advances in the understanding of its pathogenesis have opened new fields of therapeutic interventions. The phagocytosis of platelets by splenic macrophages could be inhibited by spleen tyrosine kinase (Syk) or Bruton tyrosine kinase (BTK) inhibitors. The clearance of antiplatelet antibodies could be accelerated by blocking the neonatal Fc receptor (FcRn), while n…

Physiopathologie des artérites à cellules géantes

Resume L’arterite a cellules geantes (ACG) et l’arterite de Takayasu sont deux vascularites granulomateuses affectant les vaisseaux de gros calibre dont la cause exacte n’est pas connue. Neanmoins, les mecanismes physiopathologiques impliques au cours de l’ACG sont de mieux en mieux identifies et ont permis l’emergence de nouvelles cibles therapeutiques comme le blocage de la signalisation de l’interleukine-6 (IL-6). Le facteur declenchant de ces vascularites n’est pas connu mais l’hypothese, jamais confirmee a ce jour, d’un agent infectieux activant les cellules dendritiques de l’adventice est privilegiee. Cette activation de la reponse immunitaire innee permet le recrutement et l’activati…

Preferential splenic CD8+ T-cell activation in rituximab-nonresponder patients with immune thrombocytopenia

The pathogenic role of B cells in immune thrombocytopenia (ITP) has justified the therapeutic use of anti-CD20 antibodies such as rituximab (RTX). However, 60% of ITP patients do not respond to RTX. To decipher the mechanisms implicated in the failure of RTX, and because the spleen plays a well-recognized role in ITP pathogenesis, 12 spleens from ITP patients who had been nonresponders to RTX therapy were compared with 11 spleens from RTX-untreated ITP patients and 9 controls. We here demonstrate that in RTX-nonresponder ITP patients, preferential Th1 and Tc1 T lymphocyte polarizations occur, associated with an increase in splenic effector memory CD8(+) T-cell frequency. Moreover, in the RT…