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2.
Nat Commun ; 10(1): 3106, 2019 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-31308374

RESUMO

Immune responses need to be controlled tightly to prevent autoimmune diseases, yet underlying molecular mechanisms remain partially understood. Here, we identify biallelic mutations in three patients from two unrelated families in differentially expressed in FDCP6 homolog (DEF6) as the molecular cause of an inborn error of immunity with systemic autoimmunity. Patient T cells exhibit impaired regulation of CTLA-4 surface trafficking associated with reduced functional CTLA-4 availability, which is replicated in DEF6-knockout Jurkat cells. Mechanistically, we identify the small GTPase RAB11 as an interactor of the guanine nucleotide exchange factor DEF6, and find disrupted binding of mutant DEF6 to RAB11 as well as reduced RAB11+CTLA-4+ vesicles in DEF6-mutated cells. One of the patients has been treated with CTLA-4-Ig and achieved sustained remission. Collectively, we uncover DEF6 as player in immune homeostasis ensuring availability of the checkpoint protein CTLA-4 at T-cell surface, identifying a potential target for autoimmune and/or cancer therapy.

3.
Front Immunol ; 10: 951, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31114586

RESUMO

The maintenance of B cell homeostasis requires a tight control of B cell generation, survival, activation, and maturation. In lymphocytes upon activation, increased sensitivity to apoptotic signals helps controlling differentiation and proliferation. The death receptor Fas is important in this context because genetic Fas mutations in humans lead to an autoimmune lymphoproliferative syndrome that is similar to lymphoproliferation observed in Fas-deficient mice. In contrast, the physiological role of TNF-related apoptosis-inducing ligand receptors (TRAIL-Rs) in humans has been poorly studied so far. Indeed, most studies have focused on tumor cell lines and on mouse models whose results are difficult to transpose to primary human B cells. In the present work, the expression of apoptosis-inducing TRAIL-R1 and TRAIL-R2 and of the decoy receptors TRAIL-R3 and TRAIL-R4 was systematically studied in all developmental stages of peripheral B cells isolated from the blood and secondary lymphoid organs. Expression of TRAIL-Rs is modulated along development, with highest levels observed in germinal center B cells. In addition, T-dependent and T-independent signals elicited induction of TRAIL-Rs with distinct kinetics, which differed among B cell subpopulations: switched memory cells rapidly upregulated TRAIL-R1 and -2 upon activation while naïve B cells only reached similar expression levels at later time points in culture. Increased expression of TRAIL-R1 and -2 coincided with a caspase-3-dependent sensitivity to TRAIL-induced apoptosis in activated B cells but not in freshly isolated resting B cells. Finally, both TRAIL-R1 and TRAIL-R2 could signal actively and both contributed to TRAIL-induced apoptosis. In conclusion, this study provides a systematic analysis of the expression of TRAIL-Rs in human primary B cells and of their capacity to signal and induce apoptosis. This dataset forms a basis to further study and understand the dysregulation of TRAIL-Rs and TRAIL expression observed in autoimmune diseases. Additionally, it will be important to foresee potential bystander immunomodulation when TRAIL-R agonists are used in cancer treatment.

4.
J Autoimmun ; 101: 145-152, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31054942

RESUMO

BACKGROUND: Cytotoxic T lymphocyte antigen-4 (CTLA-4) limits T-cell activation and is expressed on T-regulatory cells. Human CTLA-4 deficiency results in severe immune dysregulation. Abatacept (CTLA-4 Ig) is approved for the treatment of rheumatoid arthritis (RA) and its mechanism of action is attributed to effects on T-cells. It is known that CTLA-4 modulates the expression of its ligands CD80 and CD86 on antigen presenting cells (APC) by transendocytosis. As B-cells express CD80/CD86 and function as APC, we hypothesize that B-cells are a direct target of abatacept. OBJECTIVES: To investigate direct effects of abatacept on human B-lymphocytes in vitro and in RA patients. METHODS: The effect of abatacept on healthy donor B-cells' phenotype, activation and CD80/CD86 expression was studied in vitro. Nine abatacept-treated RA patients were studied. Seven of these were followed up to 24 months, and two up to 12 months only and treatment response, immunoglobulins, ACPA, RF concentrations, B-cell phenotype and ACPA-specific switched memory B-cell frequency were assessed. RESULTS: B-cell development was unaffected by abatacept. Abatacept treatment resulted in a dose-dependent decrease of CD80/CD86 expression on B-cells in vitro, which was due to dynamin-dependent internalization. RA patients treated with abatacept showed a progressive decrease in plasmablasts and serum IgG. While ACPA-titers only moderately declined, the frequency of ACPA-specific switched memory B-cells significantly decreased. CONCLUSIONS: Abatacept directly targets B-cells by reducing CD80/CD86 expression. Impairment of antigen presentation and T-cell activation may result in altered B-cell selection, providing a new therapeutic mechanism and a base for abatacept use in B-cell mediated autoimmunity.

5.
Front Immunol ; 10: 514, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30941143

RESUMO

Objective: Rheumatic diseases with involvement of the central nervous system (RDwCNS) may mimic multiple sclerosis (MS). Inversely, up to 60% of MS-patients have antinuclear autoantibodies (ANAs) and may be misdiagnosed as RDwCNS. The detection of antibodies against extractable nuclear antigens (ENA) and oligoclonal bands (OCB) are established valuable diagnostic tools in the differential diagnosis of RDwCNS and MS. The MRZ-reaction (MRZR) is defined by three antibody indices (AIs) against neurotropic viruses and is frequently positive in MS. To investigate the added value of MRZR combined with testing for antibodies against ENAs and OCB detection to distinguish RDwCNS from ANA positive MS. Methods: MRZR was evaluated in RDwCNS (n = 40) and 68 ANA positive MS-patients. Two stringency levels, MRZR-1 and MRZR-2 (at least one respectively two of three AIs positive) were applied. Autoantibody testing included ANA plus ENA and anti-dsDNA antibodies, antiphospholipid antibodies, and anti-neutrophil cytoplasmic antibodies. Results: Most of the RDwCNS patients (n = 32; 80%) suffered from systemic lupus erythematosus. Within the RDwCNS group 20% had a positive MRZR-1 and 8.5% a positive MRZR-2 compared to 80.9 and 60%, respectively within the MS-group (p < 0.0001 for both comparisons). Oligoclonal bands were found in 28.6% of the RDwCNS patients and 94.3% of the MS-patients (p < 0.0001). Conversely, autoantibodies to specific nuclear antigens or phospholipids were found more frequently in RDwCNS. A positive MRZR in conjunction with the absence of ENA autoantibodies distinguished MS from RDwCNS with high specificity (97.5%). Conclusions: We suggest combining MRZR, OCBs, and specific autoantibody diagnostics to differentiate RDwCNS from MS.

6.
J Autoimmun ; 100: 131-136, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30862449

RESUMO

INTRODUCTION: Dermatomyositis (DM) can be complicated by calcinosis and interstitial lung disease (ILD). Calcinosis can be severely debilitating or life-threatening and to date there is no treatment with proven efficacy. In DM type I interferon contributes to pathophysiology by inducing the expression of proinflammatory cytokines and the JAK-STAT (signal transducer and activator of transcription) pathway may be involved in the regulation of mitochondrial calcium store release, a process potentially important for calcification in DM. JAK-inhibition may therefore be an attractive therapy in DM complicated by calcifications. METHODS AND RESULTS: We report on the fast and persistent response of extensive and rapidly progressive DM-associated calcifications in two patients treated with the JAK-inhibitor tofacitinib. During the 28-week observation period in both patients no new calcifications formed and existing calcifications were either regressive or stable. Furthermore, concomitant life-threatening DM-associated ILD (acute fibrinous and organizing pneumonia; AFOP) in one patient rapidly responded to tofacitinib monotherapy. Both patients were able to taper concomitant glucocorticoids. Tofacitinib was well tolerated and safe. CONCLUSIONS: The results of our study support the role of JAK/STAT signaling in the development of calcinosis and ILD in DM. Tofacitinib may be an effective and safe treatment for calcinosis in DM and potentially for other connective tissue disease complicated by calcinosis.

7.
BMC Neurol ; 18(1): 14, 2018 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-29386006

RESUMO

BACKGROUND: Some rheumatologic disorders may initially manifest with central nervous system (CNS) affection, mimicking the clinical, magnetic resonance imaging, and cerebrospinal fluid findings of multiple sclerosis (MS). The MRZ reaction (MRZR), composed of the three respective antibody indices (AIs) against measles, rubella, and varicella zoster virus, has been found positive frequently in MS patients. However, it is unclear whether the MRZR is helpful to distinguish rheumatologic disorders with CNS involvement (RDwCNS) from MS. METHODS: The MRZR was evaluated in patients with RDwCNS (n = 23), MS (n = 46; age and sex matched to patients with RDwCNS), and other inflammatory autoimmune neurological diseases affecting the CNS (OIND; n = 48). Both the stringency levels that have been used in previous MRZR studies, MRZR-1 (≥ 1 of 3 AIs positive) and MRZR-2 (≥ 2 of 3 AIs positive), were applied. RESULTS: There was no statistically significant difference in the prevalence of positive MRZR between patients with RDwCNS (MRZR-1: 13.0% and MRZR-2: 8.7%, respectively) and OIND (MRZR-1: 22.9% and MRZR-2: 8.3%, respectively). Compared to these two study cohorts, the MS group exhibited significantly higher prevalences of positive MRZR (MRZR-1: 82.6%, MRZR-2: 63.0%; p < 0.005 each). CONCLUSIONS: Considering the high specificity of MRZR-2 for MS found in this study, MRZR-2 can be a useful diagnostic tool for distinguishing MS from RDwCNS or OIND.


Assuntos
Anticorpos Antivirais/líquido cefalorraquidiano , Artrite Reumatoide/diagnóstico , Esclerose Múltipla/diagnóstico , Adulto , Idoso , Diagnóstico Diferencial , Feminino , Herpesvirus Humano 3/imunologia , Humanos , Masculino , Vírus do Sarampo/imunologia , Pessoa de Meia-Idade , Estudos Retrospectivos , Vírus da Rubéola/imunologia , Adulto Jovem
8.
J Allergy Clin Immunol Pract ; 5(6): 1556-1563, 2017 Nov - Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28916432

RESUMO

BACKGROUND: Rituximab (RTX) is approved for induction therapy of granulomatosis with polyangiitis and microscopic polyangiitis. In eosinophilic granulomatosis with polyangiitis (EGPA), organ-threatening manifestations are mainly treated with cyclophosphamide (CYC). RTX as treatment in EGPA has been described in small case series; however long-term data and the efficacy of RTX in EGPA refractory to CYC have not been reported yet. OBJECTIVES: To investigate the efficacy and safety of RTX and conventional immunosuppressive therapy with CYC in EGPA as induction therapy and during long-term follow-up. METHODS: Retrospective analysis of 28 patients with EGPA was done. Treatment response and disease activity were determined by Birmingham Vasculitis Activity Score, C-reactive protein, eosinophils, antineutrophil cytoplasmic antibody, and peripheral CD19+ B cells. RESULTS: Fourteen patients with EGPA treated with RTX were compared with 14 age- and sex-matched patients with EGPA treated with CYC for remission induction; 64% of the RTX-treated patients with EGPA had previously failed CYC treatment. Disease duration was longer and the number of previous immunosuppressants higher in RTX-treated patients. Five RTX-treated patients (36%) and 4 CYC-treated patients (29%) achieved complete remission. All other patients were in partial remission. There was no difference between both groups in respect to treatment response and partial and complete remission. In both treatment groups, eosinophils, C-reactive protein, and IgE levels dropped. Relapse-free survival within an observation period of 36 months was comparable between RTX- and CYC-treated patients. RTX was well tolerated, but resulted in a decline in serum immunoglobulin levels. CONCLUSIONS: RTX was effective in inducing remission and during long-term follow-up in patients with EGPA, even when previously refractory to standard immunosuppressive therapy including CYC. RTX-treated patients should be monitored for hypogammaglobulinemia.


Assuntos
Linfócitos B/imunologia , Síndrome de Churg-Strauss/tratamento farmacológico , Ciclofosfamida/uso terapêutico , Eosinófilos/imunologia , Granulomatose com Poliangiite/tratamento farmacológico , Imunossupressores/uso terapêutico , Rituximab/uso terapêutico , Adulto , Anticorpos Anticitoplasma de Neutrófilos/metabolismo , Proteína C-Reativa/metabolismo , Quimioterapia Combinada , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento
9.
Orphanet J Rare Dis ; 12(1): 99, 2017 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-28545554

RESUMO

BACKGROUND: Whipple's disease, a rare chronic infectious disorder caused by Tropheryma whipplei, may present with predominant joint manifestations mimicking rheumatoid arthritis (RA). METHODS: A retrospective single-center cohort study of seven patients was performed. Clinical symptoms were assessed by review of medical charts and Whipple's disease was diagnosed by periodic-acid-Schiff-stain and/or Tropheryma whipplei-specific polymerase-chain-reaction. RESULTS: Median age at disease onset was 54 years, six patients were male. Median time to diagnosis was 5 years. All patients presented with polyarthritis with a predominantly symmetric pattern. Three had erosive arthritis. Affected joints were: wrists (5/7), metacarpophalangeal joints (MCPs) (5/7), knees (5/7), proximal interphalangeal joints (PIPs) (3/7), hips (2/7), elbow (2/7), shoulder (2/7). All patients had increased C-reactive-protein concentrations, while rheumatoid factor and anti-CCP-antibodies were absent, and were initially (mis)classified as RA-patients according to EULAR/ACR-criteria (median DAS28 4.3). Six patients received antirheumatic treatment consisting of prednisone with methotrexate and/or leflunomide, three were additionally treated with at least one biologic agent (abatacept, adalimumab, etanercept, rituximab, tocilizumab). Most patients showed insufficient treatment response. In all patients Tropheryma whipplei was detected in synovial fluid by polymerase-chain-reaction; in three patients the diagnosis of Whipple's disease was further ascertained by periodic-acid-Schiff-staining. Gastrointestinal symptoms and other extra-articular manifestations were absent, mild or non-specific. Treatment was initiated with trimethoprin/sulfamethoxazole in five and doxycycline/hydroxychloroquine in two patients and had to be adapted in five patients. Finally, all patients had good treatment responses with improvement of arthritis and extra-articular manifestations. CONCLUSION: Whipple's disease is rare and can mimic rheumatoid arthritis. Especially patients with seronegative rheumatoid arthritis with a prolonged disease course and insufficient treatment response should be reevaluated for Whipple's disease.


Assuntos
Antibacterianos/uso terapêutico , Artrite Reumatoide/diagnóstico , Artrite Reumatoide/tratamento farmacológico , Erros de Diagnóstico , Doença de Whipple/diagnóstico , Doença de Whipple/tratamento farmacológico , Adulto , Idoso , Estudos de Coortes , Diagnóstico Diferencial , Erros de Diagnóstico/prevenção & controle , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Falha de Tratamento
10.
Arthritis Res Ther ; 19(1): 101, 2017 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-28521808

RESUMO

BACKGROUND: B cell depletion with rituximab (RTX) is approved for treatment of rheumatoid arthritis (RA) and ANCA-associated vasculitides (AAV). Recently, RTX has been shown to be effective in AAV maintenance therapy, but an optimal RTX treatment schedule is unknown and the time to B cell repopulation after RTX has not been studied. METHODS: Retrospective single-center analysis of B cell repopulation in patients with AAV, RA or connective tissue disease (CTD) treated with RTX. RESULTS: Beginning B cell repopulation within the first year after RTX treatment was observed in 93% of RA and 88% of CTD patients. Only 10% of patients with granulomatosis with polyangiitis (GPA) and microscopic polyangiitis (MPA) and no patient with eosinophilic granulomatosis with polyangiitis (EGPA) showed B cell repopulation within this time. Median time of B cell depletion was 26 months in GPA/MPA, and 21 months in EGPA compared to 9 months in RA, and 8 months in CTD (p < 0.0001). In 25 AAV-patients B cell depletion lasted for at least 44 months. There was a significant decline in serum immunoglobulin concentrations in GPA/MPA patients, but not in patients with RA or CTD. Significantly more GPA/MPA patients developed hygogammaglobulinemia (IgG <7 g/L) compared to patients with RA or CTD. CONCLUSIONS: In contrast to RA and CTD, in AAV RTX induces long-lasting depletion of B cells that is associated with decreased antibody production. This observation points toward potential defects in the B cell compartment in AAV that are unmasked by immunosuppressive treatment and has important implications for the design of maintenance treatment schedules using RTX.


Assuntos
Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/metabolismo , Antirreumáticos/uso terapêutico , Artrite Reumatoide/metabolismo , Linfócitos B/metabolismo , Doenças do Tecido Conjuntivo/metabolismo , Rituximab/uso terapêutico , Adulto , Idoso , Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/tratamento farmacológico , Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/imunologia , Antirreumáticos/farmacologia , Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/imunologia , Linfócitos B/efeitos dos fármacos , Linfócitos B/imunologia , Doenças do Tecido Conjuntivo/tratamento farmacológico , Doenças do Tecido Conjuntivo/imunologia , Feminino , Seguimentos , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Rituximab/farmacologia , Resultado do Tratamento
11.
J Autoimmun ; 77: 55-66, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27793425

RESUMO

B-cells are pivotal to the pathogenesis of rheumatoid arthritis and tofacitinib, a JAK inhibitor, is effective and safe in its treatment. Tofacitinib interferes with signal transduction via cytokine receptors using the common γ-chain. Despite extensive data on T-lymphocytes, the impact of tofacitinib on B-lymphocytes is poorly understood. In this study we assessed the effect of tofacitinib on B-lymphocyte differentiation and function. Tofacitinib treatment strongly impaired in vitro plasmablast development, immunoglobulin secretion and induction of B-cell fate determining transcription factors, Blimp-1, Xbp-1, and IRF-4, in naïve B-cells. Interestingly, class switch and activation-induced cytidine deaminase (AICDA) induction was only slightly reduced in activated naïve B-cells. The effect of tofacitinib on plasmablast formation, immunoglobulin secretion and proliferation was less profound, when peripheral blood B-cells, including not only naïve but also memory B-cells, were stimulated. In line with these in vitro results, the relative distribution of B-cell populations remained stable in tofacitinib treated patients. Nevertheless, a temporary increase in absolute B-cell numbers was observed 6-8 weeks after start of treatment. In addition, B-cells isolated from tofacitinib treated patients responded rapidly to in vitro activation. We demonstrate that tofacitinib has a direct impact on human naïve B-lymphocytes, independently from its effect on T-lymphocytes, by impairing their development into plasmablasts and immunoglobulin secretion. The major effect of tofacitinib on naïve B-lymphocyte development points to the potential inability of tofacitinib-treated patients to respond to novel antigens, and suggests planning vaccination strategies prior to tofacitinib treatment.


Assuntos
Linfócitos B/efeitos dos fármacos , Linfócitos B/imunologia , Piperidinas/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Pirimidinas/farmacologia , Pirróis/farmacologia , Formação de Anticorpos/efeitos dos fármacos , Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/imunologia , Artrite Reumatoide/metabolismo , Linfócitos B/metabolismo , Células Cultivadas , Citidina Desaminase/metabolismo , Humanos , Switching de Imunoglobulina/efeitos dos fármacos , Imunomodulação , Subunidade gama Comum de Receptores de Interleucina/metabolismo , Ativação Linfocitária/efeitos dos fármacos , Ativação Linfocitária/imunologia , Contagem de Linfócitos , Piperidinas/uso terapêutico , Plasmócitos/efeitos dos fármacos , Plasmócitos/imunologia , Plasmócitos/metabolismo , Inibidores de Proteínas Quinases/uso terapêutico , Pirimidinas/uso terapêutico , Pirróis/uso terapêutico , Transdução de Sinais/efeitos dos fármacos
12.
J Allergy Clin Immunol ; 136(2): 402-12, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25724123

RESUMO

BACKGROUND: Mutations in dedicator of cytokinesis 8 (DOCK8) cause a combined immunodeficiency (CID) also classified as autosomal recessive (AR) hyper-IgE syndrome (HIES). Recognizing patients with CID/HIES is of clinical importance because of the difference in prognosis and management. OBJECTIVES: We sought to define the clinical features that distinguish DOCK8 deficiency from other forms of HIES and CIDs, study the mutational spectrum of DOCK8 deficiency, and report on the frequency of specific clinical findings. METHODS: Eighty-two patients from 60 families with CID and the phenotype of AR-HIES with (64 patients) and without (18 patients) DOCK8 mutations were studied. Support vector machines were used to compare clinical data from 35 patients with DOCK8 deficiency with those from 10 patients with AR-HIES without a DOCK8 mutation and 64 patients with signal transducer and activator of transcription 3 (STAT3) mutations. RESULTS: DOCK8-deficient patients had median IgE levels of 5201 IU, high eosinophil levels of usually at least 800/µL (92% of patients), and low IgM levels (62%). About 20% of patients were lymphopenic, mainly because of low CD4(+) and CD8(+) T-cell counts. Fewer than half of the patients tested produced normal specific antibody responses to recall antigens. Bacterial (84%), viral (78%), and fungal (70%) infections were frequently observed. Skin abscesses (60%) and allergies (73%) were common clinical problems. In contrast to STAT3 deficiency, there were few pneumatoceles, bone fractures, and teething problems. Mortality was high (34%). A combination of 5 clinical features was helpful in distinguishing patients with DOCK8 mutations from those with STAT3 mutations. CONCLUSIONS: DOCK8 deficiency is likely in patients with severe viral infections, allergies, and/or low IgM levels who have a diagnosis of HIES plus hypereosinophilia and upper respiratory tract infections in the absence of parenchymal lung abnormalities, retained primary teeth, and minimal trauma fractures.


Assuntos
Infecções Bacterianas/complicações , Fatores de Troca do Nucleotídeo Guanina/deficiência , Síndrome de Job/complicações , Fenótipo , Dermatopatias/complicações , Viroses/complicações , Adolescente , Adulto , Antígenos de Bactérias/sangue , Antígenos de Bactérias/imunologia , Antígenos Virais/sangue , Antígenos Virais/imunologia , Infecções Bacterianas/genética , Infecções Bacterianas/imunologia , Infecções Bacterianas/mortalidade , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/patologia , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/patologia , Criança , Pré-Escolar , Eosinófilos/imunologia , Eosinófilos/patologia , Feminino , Fatores de Troca do Nucleotídeo Guanina/genética , Fatores de Troca do Nucleotídeo Guanina/imunologia , Humanos , Imunoglobulina E/sangue , Imunoglobulina E/genética , Imunoglobulina M/sangue , Imunoglobulina M/genética , Lactente , Síndrome de Job/genética , Síndrome de Job/imunologia , Síndrome de Job/mortalidade , Contagem de Linfócitos , Masculino , Pessoa de Meia-Idade , Mutação , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/imunologia , Dermatopatias/genética , Dermatopatias/imunologia , Dermatopatias/mortalidade , Máquina de Vetores de Suporte , Análise de Sobrevida , Viroses/genética , Viroses/imunologia , Viroses/mortalidade
13.
J Clin Immunol ; 35(2): 189-98, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25627830

RESUMO

Mutations in DOCK8 result in autosomal recessive Hyper-IgE syndrome with combined immunodeficiency (CID). However, the natural course of disease, long-term prognosis, and optimal therapeutic management have not yet been clearly defined. In an international retrospective survey of patients with DOCK8 mutations, focused on clinical presentation and therapeutic measures, a total of 136 patients with a median follow-up of 11.3 years (1.3-47.7) spanning 1693 patient years, were enrolled. Eczema, recurrent respiratory tract infections, allergies, abscesses, viral infections and mucocutaneous candidiasis were the most frequent clinical manifestations. Overall survival probability in this cohort [censored for hematopoietic stem cell transplantation (HSCT)] was 87 % at 10, 47 % at 20, and 33 % at 30 years of age, respectively. Event free survival was 44, 18 and 4 % at the same time points if events were defined as death, life-threatening infections, malignancy or cerebral complications such as CNS vasculitis or stroke. Malignancy was diagnosed in 23/136 (17 %) patients (11 hematological and 9 epithelial cancers, 5 other malignancies) at a median age of 12 years. Eight of these patients died from cancer. Severe, life-threatening infections were observed in 79/136 (58 %); severe non-infectious cerebral events occurred in 14/136 (10 %). Therapeutic measures included antiviral and antibacterial prophylaxis, immunoglobulin replacement and HSCT. This study provides a comprehensive evaluation of the clinical phenotype of DOCK8 deficiency in the largest cohort reported so far and demonstrates the severity of the disease with relatively poor prognosis. Early HSCT should be strongly considered as a potential curative measure.


Assuntos
Estudos de Associação Genética , Fatores de Troca do Nucleotídeo Guanina/deficiência , Fatores de Troca do Nucleotídeo Guanina/genética , Adolescente , Adulto , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Seguimentos , Humanos , Imunoglobulina E/sangue , Imunoglobulina E/imunologia , Incidência , Lactente , Infecção/diagnóstico , Infecção/epidemiologia , Infecção/etiologia , Síndrome de Job/complicações , Síndrome de Job/diagnóstico , Síndrome de Job/genética , Síndrome de Job/imunologia , Síndrome de Job/mortalidade , Síndrome de Job/terapia , Contagem de Linfócitos , Subpopulações de Linfócitos/imunologia , Subpopulações de Linfócitos/metabolismo , Masculino , Pessoa de Meia-Idade , Mutação , Neoplasias/epidemiologia , Neoplasias/etiologia , Fenótipo , Adulto Jovem
14.
Autoimmunity ; 47(6): 401-8, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24798501

RESUMO

While in patients with rheumatoid arthritis B-cell repopulation starts within 9 months after rituximab (RTX) therapy, a delayed B-cell repopulation was reported in some RTX-treated patients with ANCA-associated vasculitides (AAV). To date, the frequency of AAV patients with impaired peripheral B-cell regeneration and the mechanisms leading to the constricted regenerative capacity are unknown. We analyzed the B-cell repopulation kinetic in 37 AAV patients treated with RTX followed by maintenance immunosuppressants. We report on serum concentrations of the B-cell-activating factor BAFF, immunoglobulins and B-cell subpopulations in patients that relapsed after RTX. B-cells were re-detectable in only one patient within 9 months after RTX. In 14 patients (41%), B-cell repopulation started later, after a mean observation time of 21 months. Only seven of these patients had detectable B-cells within the first year after RTX. Twenty patients (59%) had no B-cell reconstitution within the observation period. BAFF was increased in RTX-treated AAV patients compared to healthy controls and correlated inversely with peripheral B-cell numbers, IgG- and IgA concentrations. Immunoglobulin concentrations declined significantly after RTX and the IgG concentration correlated with B-cell numbers. Thirteen patients relapsed after RTX. Relapses occurred exclusively either after B-cell reconstitution had started or were accompanied by rising ANCA titres. In relapsed patients, the B-lymphocyte compartment consisted mainly of switched memory B-cells. Our data indicate that RTX treatment can induce secondary immunodeficiency in AAV, with hypogammaglobulinemia and long-lasting B-lymphopenia. Further studies are needed to define the pathophysiology of the impaired B-cell development in RTX-treated AAV patients.


Assuntos
Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/imunologia , Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/terapia , Anticorpos Monoclonais Murinos , Antirreumáticos , Linfócitos B/imunologia , Agamaglobulinemia/etiologia , Agamaglobulinemia/imunologia , Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/fisiopatologia , Anticorpos Monoclonais Murinos/efeitos adversos , Anticorpos Monoclonais Murinos/uso terapêutico , Antirreumáticos/efeitos adversos , Antirreumáticos/uso terapêutico , Linfócitos B/patologia , Contagem de Células , Humanos , Memória Imunológica , Linfopenia/etiologia , Linfopenia/imunologia , Recidiva , Rituximab
15.
Exp Dermatol ; 23(4): 236-7, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24450995

RESUMO

CD20-specific antibodies show remarkable therapeutic efficacy in B-cell malignancy and autoimmune diseases, but due to the occurrence of a significant treatment resistance, a critical, unmet need for improving B-cell-depleting approaches remains. A CD20 transcript variant (D393-CD20) appears to be associated with Rituximab treatment resistance in malignant B cells, but is lacking in patients with autoimmune dermatoses as shown by Gamonet et al. While CD20-specific factors certainly play a major role in the pathogenesis of Rituximab treatment resistance, the D393-CD2 transcript may greatly facilitate the development of clinical markers for monitoring the therapy in B-cell malignancies and (auto)antibody-mediated diseases. Its association with systemic autoimmune diseases should be therefore explored in further studies.


Assuntos
Anticorpos Monoclonais Murinos , Antígenos CD20/metabolismo , Resistencia a Medicamentos Antineoplásicos , Fatores Imunológicos , Processamento Alternativo , Anticorpos Monoclonais Murinos/uso terapêutico , Doenças Autoimunes/tratamento farmacológico , Biomarcadores/metabolismo , Humanos , Fatores Imunológicos/uso terapêutico , Rituximab , Dermatopatias/tratamento farmacológico
16.
Arthritis Res Ther ; 15(5): R133, 2013 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-24286362

RESUMO

INTRODUCTION: Eosinophilic granulomatosis with polyangiitis (EGPA) is part of antineutrophil cytoplasmic antibodies (ANCAs)-associated vasculitides. In EGPA small-vessel vasculitis is associated with eosinophilia and asthma. About 40% of EGPA patients are ANCA-positive, suggesting a role for B cells in the pathogenesis of EGPA. B cell-depleting therapy with rituximab (RTX) can be effective in ANCA-positive EGPA, but very few patients have been published to date. The role of RTX in the treatment of ANCA-negative EGPA is unclear. METHODS: We report a single-center cohort of patients with eosinophilic granulomatosis with polyangiitis. Of these patients, nine (six ANCA-positive, three ANCA-negative) had been treated with RTX for relapsing or refractory disease on standard immunosuppressive treatment. In a retrospective analysis, data on treatment response, frequency of relapses, adverse events, and peripheral B-cell reconstitution were evaluated. Furthermore, serum immunoglobulin concentrations, ANCA status, and peripheral B cell subpopulations were assessed after RTX treatment. RESULTS: All patients had high disease activity before RTX treatment. At presentation 3 months after RTX therapy, all ANCA-positive and ANCA-negative patients had responded to RTX, with one patient being in complete remission, and eight patients being in partial remission. After a mean follow-up of 9 months, C-reactive protein concentrations had normalized, eosinophils had significantly decreased, and prednisone had been tapered in all patients. In all patients, RTX therapy was combined with a standard immunosuppressive therapy. Within the 9-month observation period, no relapse was recorded. Three patients were preemptively retreated with RTX, and during the median follow-up time of 3 years, no relapse occurred in these patients. During the follow-up of 13 patient-years, five minor but no major infections were recorded. CONCLUSIONS: In our analysis on nine patients with EGPA resistant to standard therapy, rituximab proved to be an efficient and safe treatment for ANCA-positive and ANCA-negative patients. Preemptive retreatment with RTX, combined with standard maintenance immunosuppressants, resulted in a sustained treatment response. Prospective, randomized trials evaluating the use of RTX in EGPA are warranted.


Assuntos
Anticorpos Monoclonais Murinos/uso terapêutico , Síndrome de Churg-Strauss/tratamento farmacológico , Adulto , Anticorpos Anticitoplasma de Neutrófilos/sangue , Antirreumáticos/uso terapêutico , Subpopulações de Linfócitos B/efeitos dos fármacos , Subpopulações de Linfócitos B/metabolismo , Proteína C-Reativa/metabolismo , Síndrome de Churg-Strauss/sangue , Síndrome de Churg-Strauss/patologia , Resistência a Medicamentos , Feminino , Seguimentos , Humanos , Imunoglobulina E/sangue , Imunossupressores/uso terapêutico , Contagem de Linfócitos , Masculino , Pessoa de Meia-Idade , Recidiva , Estudos Retrospectivos , Rituximab , Fatores de Tempo , Resultado do Tratamento
17.
Autoimmunity ; 46(7): 429-38, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23742274

RESUMO

B-lymphocytes play a pivotal role in ANCA-associated vasculitides (AAV). The homeostasis of peripheral human B-lymphocyte subpopulations is tightly regulated, but may be disturbed in autoimmune disease or following immunosuppressive therapies. To elucidate the effect of immunosuppression and the relevance of B-lymphocyte disturbances, the B-lymphocyte compartment was analysed in 61 AAV patients. After immunosuppressive treatment a general B-lymphocytopenia developed in AAV patients. Within the B-lymphocyte subpopulations transitional B cells are the first maturation stage found in the peripheral blood. Transitional B-lymphocytes were significantly lower in AAV patients after immunosuppressive therapy compared to healthy controls. Furthermore, marginal zone B cells--a B-lymphocyte population protecting against encapsulated bacteria--were markedly lowered after immunosuppressive therapy in AAV patients. AAV patients treated with immunosuppressants had lower numbers of naïve and memory B-lymphocytes. Numbers of marginal zone B cells, memory B cells and plasmablasts correlated with concentrations of immunoglobulins. We evaluated plasmablasts for a potential correlation with disease activity. Different from what has been reported for e.g. large vessel vasculitis, absolute numbers of plasmablasts were not increased in patients with AAV and showed no correlation to disease activity. As low transitional B cells after treatment with immunosuppressants indicated an impaired early B-lymphocyte development, seven patients treated with the B cell depleting agent rituximab (RTX) because of relapsing disease activity were analysed for their B cell repopulation kinetics. In the majority of these patients repopulation of the peripheral B cell compartment by newly formed transitional B cells after RTX treatment was constricted and delayed.


Assuntos
Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/tratamento farmacológico , Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/patologia , Subpopulações de Linfócitos B/imunologia , Subpopulações de Linfócitos B/patologia , Homeostase/imunologia , Imunossupressores/administração & dosagem , Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/imunologia , Anticorpos Monoclonais Murinos/administração & dosagem , Anticorpos Monoclonais Murinos/efeitos adversos , Azatioprina/administração & dosagem , Azatioprina/efeitos adversos , Subpopulações de Linfócitos B/efeitos dos fármacos , Ciclofosfamida/administração & dosagem , Ciclofosfamida/efeitos adversos , Feminino , Homeostase/efeitos dos fármacos , Humanos , Imunossupressores/efeitos adversos , Isoxazóis/administração & dosagem , Isoxazóis/efeitos adversos , Leflunomida , Contagem de Linfócitos , Masculino , Metotrexato/administração & dosagem , Metotrexato/efeitos adversos , Pessoa de Meia-Idade , Ácido Micofenólico/administração & dosagem , Ácido Micofenólico/efeitos adversos , Ácido Micofenólico/análogos & derivados , Rituximab
18.
J Clin Immunol ; 33(5): 909-16, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23609110

RESUMO

OBJECTIVES: Gastrointestinal manifestations are frequent in patients with common variable immunodeficiency (CVID), and some of the patients present with celiac-like features. Diagnosing celiac disease (CD) in CVID however is challenging, as autoantibody detection and histopathology of the small intestine cannot reliably discriminate between classic CD and a celiac-like disease in these individuals. For the development of classic gluten-sensitive CD a certain HLA haplotype involving the loci DQA1* and DQB1* and encoding two different HLA DQ heterodimers is the prerequisite. We aimed to determine the frequency of these haplotypes in CVID patients with suspected CD. Furthermore, we report on autoimmune manifestations and the lymphocyte phenotype in these patients. METHODS: By retrospective analysis data on gastrointestinal symptoms, diet, concurrent autoimmune diseases, and routine laboratory values were collected. CVID patients were classified according to their B-cell phenotype. Expression of HLA-DQA1* and HLA-DQB1* alleles were determined by genetic analysis. RESULTS: Twenty out of 250 CVID patients presented with a clinical phenotype resembling celiac disease. Four (20%) out of these CVID patients carried the CD-associated HLA DQ2.5 or DQ8 heterodimer, while HLA DQ2.5 was present in 100% of a CD control cohort. Gluten-free diet (GFD) resulted in a clinical and histological response in two out of four patients with HLA high-risk alleles for CD. The response could not be assessed in the remaining two patients, as these patients did not adhere sufficiently long to GFD. The percentage of autoimmune manifestations other than CD was high (50%) in CVID patients presenting with a CD-like enteropathy, and most of these patients had an expansion of B-cells with low expression of CD21 (CD21low B-cells). CONCLUSIONS: In CVID patients with suspected celiac disease typing of the HLA loci DQA1 and DQB1 can help to identify those that have a genetic susceptibility for CD. In CVID patients with a celiac-like phenotype but negative for CD-associated HLA-DQ markers, an autoimmune enteropathy (AIE) as part of an extended autoimmune dysregulation needs to be considered. This has important implications for further diagnostics and therapy of these patients.


Assuntos
Doença Celíaca/genética , Imunodeficiência de Variável Comum/genética , Antígenos HLA-DQ/genética , Adulto , Alelos , Doenças Autoimunes/genética , Doenças Autoimunes/imunologia , Linfócitos B/imunologia , Doença Celíaca/imunologia , Imunodeficiência de Variável Comum/imunologia , Dieta Livre de Glúten , Feminino , Frequência do Gene , Testes Genéticos/métodos , Antígenos HLA-DQ/imunologia , Cadeias alfa de HLA-DQ/genética , Cadeias alfa de HLA-DQ/imunologia , Cadeias beta de HLA-DQ/genética , Cadeias beta de HLA-DQ/imunologia , Humanos , Linfócitos/imunologia , Masculino , Pessoa de Meia-Idade , Fenótipo , Receptores de Complemento 3d/genética , Receptores de Complemento 3d/imunologia , Estudos Retrospectivos , Adulto Jovem
20.
PLoS One ; 7(5): e37626, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22629432

RESUMO

OBJECTIVE: To assess the impact of immunosuppressive therapy with cyclophosphamide (CYC) and rituximab (RTX) on serum immunoglobulin (Ig) concentrations and B lymphocyte counts in patients with ANCA-associated vasculitides (AAVs). METHODS: Retrospective analysis of Ig concentrations and peripheral B cell counts in 55 AAV patients. RESULTS: CYC treatment resulted in a decrease in Ig levels (median; interquartile range IQR) from IgG 12.8 g/L (8.15-15.45) to 9.17 g/L (8.04-9.90) (p = 0.002), IgM 1.05 g/L (0.70-1.41) to 0.83 g/L (0.60-1.17) (p = 0.046) and IgA 2.58 g/L (1.71-3.48) to 1.58 g/L (1-31-2.39) (p = 0.056) at a median follow-up time of 4 months. IgG remained significantly below the initial value at 14.5 months and 30 months analyses. Subsequent RTX treatment in patients that had previously received CYC resulted in a further decline in Ig levels from pre RTX IgG 9.84 g/L (8.71-11.60) to 7.11 g/L (5.75-8.77; p = 0.007), from pre RTX IgM 0.84 g/L (0.63-1.18) to 0.35 g/L (0.23-0.48; p<0.001) and from pre RTX IgA 2.03 g/L (1.37-2.50) to IgA 1.62 g/L (IQR 0.84-2.43; p = 0.365) 14 months after RTX. Treatment with RTX induced a complete depletion of B cells in all patients. After a median observation time of 20 months median B lymphocyte counts remained severely suppressed (4 B-cells/µl, 1.25-9.5, p<0.001). Seven patients (21%) that had been treated with CYC followed by RTX were started on Ig replacement because of severe bronchopulmonary infections and serum IgG concentrations below 5 g/L. CONCLUSIONS: In patients with AAVs, treatment with CYC leads to a decline in immunoglobulin concentrations. A subsequent RTX therapy aggravates the decline in serum immunoglobulin concentrations and results in a profoundly delayed B cell repopulation. Surveying patients with AAVs post CYC and RTX treatment for serum immunoglobulin concentrations and persisting hypogammaglobulinemia is warranted.


Assuntos
Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/tratamento farmacológico , Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/imunologia , Anticorpos Monoclonais Murinos/uso terapêutico , Linfócitos B/efeitos dos fármacos , Ciclofosfamida/uso terapêutico , Imunoglobulinas/sangue , Fatores Imunológicos/uso terapêutico , Adulto , Idoso , Anticorpos Monoclonais Murinos/farmacologia , Linfócitos B/imunologia , Ciclofosfamida/farmacologia , Feminino , Humanos , Fatores Imunológicos/farmacologia , Contagem de Linfócitos , Masculino , Pessoa de Meia-Idade , Rituximab
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