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1.
J Clin Immunol ; 2019 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-31858365

RESUMO

BACKGROUND: Inducible T cell co-stimulator (ICOS) deficiency has been categorized as a combined immunodeficiency often complicated by enteropathies, autoimmunity, lymphoproliferation, and malignancy. We report seven new patients and four novel ICOS mutations resulting in a common variable immunodeficiency (CVID)-like phenotype and show that dysregulated IL-12 release, reduced cytotoxic T lymphocyte-associated protein 4 (CTLA4) expression, and skewing towards a Th1-dominant phenotype are all associated with inflammatory complications in this condition. METHODS: A combination of whole exome and Sanger sequencing was used to identify novel mutations. Standard clinical and immunological evaluation was performed. FACS and ELISA-based assays were used to study cytokine responses and ICOS/ICOSL/CTLA4 expression following stimulation of whole blood and PBMCs with multiple TLR ligands, anti-CD3, and PHA. RESULTS: Four novel ICOS mutations included homozygous c.323_332del, homozygous c.451C>G, and compound heterozygous c.58+1G>A/c.356T>C. The predominant clinical phenotype was that of antibody deficiency associated with inflammatory complications in 4/7 patients. Six out of seven patients were treated with immunoglobulin replacement and one patient died from salmonella sepsis. All patients who were tested showed reduced IL-10 and IL-17 cytokine responses, normal IL-1ß, IL6, and TNF release following LPS stimulation and highly elevated IL-12 production in response to combined LPS/IFNγ stimulation. This was associated with skewing of CD4+ T cells towards Th1 phenotype and increased expression of ICOSL on monocytes. Lastly, reduced CTLA4 expression was found in 2 patients. One patient treated with ustekinumab for pancytopenia due to granulomatous bone marrow infiltration failed to respond to this targeted therapy. CONCLUSIONS: ICOS deficiency is associated with defective T cell activation, with simultaneously enhanced stimulation of monocytes. The latter is likely to result from a lack of ICOS/ICOSL interaction which might be necessary to provide negative feedback which limits monocytes activation.

2.
Haematologica ; 2019 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-31582539

RESUMO

Megakaryoblastic leukemia 1 (MKL1) is a coactivator of serum response factor and together regulate transcription of actin cytoskeleton genes. MKL1 is associated with hematologic malignancies and immunodeficiency, but its role in B cells is unexplored. Here we examined B cells from monozygotic triplets with an intronic deletion in MKL1, two of whom were previously treated for Hodgkin lymphoma. To investigate MKL1 and B cell responses in HL pathogenesis, we generated Epstein Barr virus-transformed lymphoblastoid cell lines from the triplets and two controls. While cells from the Hodgkin lymphoma treated patients had a phenotype close to healthy controls, cells from the undiagnosed triplet had increased MKL1 mRNA, increased MKL1 protein, and elevated expression of MKL1-dependent genes. This was associated with elevated actin content, increased cell spreading, decreased expression of CD11a integrin molecules, and delayed aggregation. Moreover, cells from the undiagnosed triplet proliferated faster, displayed a higher proportion of cells with hyperploidy, and formed large tumors in vivo. This phenotype was reversible by inhibiting MKL1 activity. Interestingly, cells from the triplet treated for Hodgkin lymphoma in 1985 contained two subpopulations: one with high expression of CD11a that behaved like control cells and the other with low expression of CD11a that formed large tumors in vivo similar to cells from the undiagnosed triplet. This implies that pre-malignant cells had re-emerged a long time after treatment. Together, these data suggest that dysregulated MKL1 activity participates in B cell transformation and Hodgkin lymphoma pathogenesis.

3.
Front Immunol ; 10: 2065, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31552026

RESUMO

Inherited Primary Immunodeficiency (PID) disorders are associated with increased risk of malignancy that may relate to impaired antitumor immune responses or a direct role for PID germline mutations in tumorigenesis. We recently identified germline loss of function mutations in Janus Associated Kinase 1 (JAK1) causing primary immunodeficiency characterized by infections and associated with early onset, fatal high-grade bladder carcinoma. Somatic mutations in JAK1, required for immune cell signaling in response to interferon gamma (IFNγ), have been associated with several non-hematopoietic and hematopoietic cancer cell types but pathogenic mechanisms remain largely unexplored. Here we demonstrate that JAK1 is required for the intrinsic IFNγ response of urothelial cells impacting immunogenicity and cell survival. Specifically, JAK1-deficient urothelial cells showed reduced surface expression of major histocompatibility complex class II (MHC II), intercellular adhesion molecule-1 (ICAM-1) and programmed death-ligand-1 (PD-L1) after IFNγ stimulation and were resistant to IFNγ-induced apoptosis and lymphocyte-mediated killing. In addition, we identify a previously unknown role for IFNγ signaling in modulating urothelial differentiation. Together, our findings support a role for urothelial cell JAK1 in immune surveillance and development of bladder cancer. Our results have implications for patients with rare JAK1 PID and, more broadly, inform development of biomarker and targeted therapies for urothelial carcinoma.

5.
Front Immunol ; 10: 297, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30941118

RESUMO

Non-canonical NF-κB-pathway signaling is integral in immunoregulation. Heterozygous mutations in NFKB2 have recently been established as a molecular cause of common variable immunodeficiency (CVID) and DAVID-syndrome, a rare condition combining deficiency of anterior pituitary hormone with CVID. Here, we investigate 15 previously unreported patients with primary immunodeficiency (PID) from eleven unrelated families with heterozygous NFKB2-mutations including eight patients with the common p.Arg853* nonsense mutation and five patients harboring unique novel C-terminal truncating mutations. In addition, we describe the clinical phenotype of two patients with proximal truncating mutations. Cohort analysis extended to all 35 previously published NFKB2-cases revealed occurrence of early-onset PID in 46/50 patients (mean age of onset 5.9 years, median 4.0 years). ACTH-deficiency occurred in 44%. Three mutation carriers have deceased, four developed malignancies. Only two mutation carriers were clinically asymptomatic. In contrast to typical CVID, most patients suffered from early-onset and severe disease manifestations, including clinical signs of T cell dysfunction e.g., chronic-viral or opportunistic infections. In addition, 80% of patients suffered from (predominately T cell mediated) autoimmune (AI) phenomena (alopecia > various lymphocytic organ-infiltration > diarrhea > arthritis > AI-cytopenia). Unlike in other forms of CVID, auto-antibodies or lymphoproliferation were not common hallmarks of disease. Immunophenotyping showed largely normal or even increased quantities of naïve and memory CD4+ or CD8+ T-cells and normal T-cell proliferation. NK-cell number and function were also normal. In contrast, impaired B-cell differentiation and hypogammaglobinemia were consistent features of NFKB2-associated disease. In addition, an array of lymphocyte subpopulations, such as regulatory T cell, Th17-, cTFH-, NKT-, and MAIT-cell numbers were decreased. We conclude that heterozygous damaging mutations in NFKB2 represent a distinct PID entity exceeding the usual clinical spectrum of CVID. Impairment of the non-canonical NF-κB pathways affects function and differentiation of numerous lymphocyte-subpopulations and thus causes a heterogeneous, more severe form of PID phenotype with early-onset. Further characteristic features are multifaceted, primarily T cell-mediated autoimmunity, such as alopecia, lymphocytic organ infiltration, and in addition frequently ACTH-deficiency.

6.
Br J Haematol ; 185(4): 647-655, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30864154

RESUMO

Wiskott Aldrich syndrome (WAS) is a primary immunodeficiency disease resulting in recurrent infections, eczema and microthrombocytopaenia. In its classical form, significant combined immune deficiency, autoimmune complications and risk of haematological malignancy necessitate early correction with stem cell transplantation or gene therapy. A milder form, X-linked thrombocytopaenia (XLT), shares similar bleeding risk from thrombocytopaenia but is not associated with other significant clinical features and is generally managed conservatively. Here, we detail our approach to the diagnosis and treatment of classical WAS and XLT.

8.
Wellcome Open Res ; 3: 84, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30483599

RESUMO

Background: Mutations of the common cytokine receptor gamma chain (γc) cause Severe Combined Immunodeficiency characterized by absent T and NK cell development. Although stem cell therapy restores these lineages, residual immune defects are observed that may result from selective persistence of γc-deficiency in myeloid lineages. However, little is known about the contribution of myeloid-expressed γc to protective immune responses.  Here we examine the importance of γc for myeloid dendritic cell (DC) function. Methods: We utilize a combination of in vitro DC/T-cell co-culture assays and a novel lipid bilayer system mimicking the T cell surface to delineate the role of DC-expressed γc during DC/T-cell interaction. Results: We observed that γc in DC was recruited to the contact interface following MHCII ligation, and promoted IL-15Rα colocalization with engaged MHCII. Unexpectedly, trans-presentation of IL-15 was required for optimal CD4+T cell activation by DC and depended on DC γc expression. Neither recruitment of IL-15Rα nor IL-15 trans-signaling at the DC immune synapse (IS), required γc signaling in DC, suggesting that γc facilitates IL-15 transpresentation through induced intermolecular cis associations or cytoskeletal reorganization following MHCII ligation. Conclusions: These findings show that DC-expressed γc is required for effective antigen-induced CD4+ T cell activation. We reveal a novel mechanism for recruitment of DC IL-15/IL-15Rα complexes to the IS, leading to CD4+ T cell costimulation through localized IL-15 transpresentation that is coordinated with antigen-recognition.

10.
Front Immunol ; 9: 1656, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30072997

RESUMO

Background: A significant amount of common variable immunodeficiency (CVID) patients manifest with autoimmunity. Particularly, autoimmune thrombocytopenia (AITP) is commonly seen. Intravenous immunoglobulins (IVIG) are an established treatment option for both, CVID and AITP. Nonetheless, due to fewer systemic side effects, immunoglobulins are increasingly applied subcutaneously (SCIG). Objective: To compare the efficacy and safety of IVIG and SCIG treatment in patients with both CVID and clinical relevant thrombocytopenia in the prevention of AITP bouts. Methods: Patients with both CVID and AITP were enrolled at the Centre for Chronic Immunodeficiency in Freiburg, Germany and at the Royal Free Hospital, London, UK. Clinical and laboratory features of patients were collected and analyzed. Results: This retrospective study recruited 61 adult patients between 19 and 71 years of age who had a diagnosis of CVID and at least one bout of thrombocytopenia defined as a platelet count of <50,000/µl if bleeding episodes occurred, or a platelet count of <20,000/µl without bleeding. Thirty patients received immunoglobulin through IVIG, and 31 patients were on SCIG replacement. One patient of the IVIG-group was excluded, because of a diffuse large B-cell lymphoma. We did not find a higher occurrence of thrombocytopenic events in CVID patients who received SCIG, compared to CVID patients who had IVIG, but we identified a low IgG through level as a risk factor for AITP bouts. Conclusion: SCIG is at least as safe as IVIG for patients with CVID and concomitant AITP. However, an IgG through level under 7 g/l is a key factor for the development of AITP.

11.
J Clin Invest ; 128(9): 3957-3975, 2018 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-29969437

RESUMO

Biallelic loss-of-function (LOF) mutations of the NCF4 gene, encoding the p40phox subunit of the phagocyte NADPH oxidase, have been described in only 1 patient. We report on 24 p40phox-deficient patients from 12 additional families in 8 countries. These patients display 8 different in-frame or out-of-frame mutations of NCF4 that are homozygous in 11 of the families and compound heterozygous in another. When overexpressed in NB4 neutrophil-like cells and EBV-transformed B cells in vitro, the mutant alleles were found to be LOF, with the exception of the p.R58C and c.120_134del alleles, which were hypomorphic. Particle-induced NADPH oxidase activity was severely impaired in the patients' neutrophils, whereas PMA-induced dihydrorhodamine-1,2,3 (DHR) oxidation, which is widely used as a diagnostic test for chronic granulomatous disease (CGD), was normal or mildly impaired in the patients. Moreover, the NADPH oxidase activity of EBV-transformed B cells was also severely impaired, whereas that of mononuclear phagocytes was normal. Finally, the killing of Candida albicans and Aspergillus fumigatus hyphae by neutrophils was conserved in these patients, unlike in patients with CGD. The patients suffer from hyperinflammation and peripheral infections, but they do not have any of the invasive bacterial or fungal infections seen in CGD. Inherited p40phox deficiency underlies a distinctive condition, resembling a mild, atypical form of CGD.


Assuntos
Doença Granulomatosa Crônica/genética , Mutação com Perda de Função , Fosfoproteínas/deficiência , Fosfoproteínas/genética , Adolescente , Adulto , Alelos , Criança , Pré-Escolar , Feminino , Técnicas de Inativação de Genes , Doença Granulomatosa Crônica/diagnóstico , Doença Granulomatosa Crônica/metabolismo , Células HEK293 , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas Mutantes/genética , Proteínas Mutantes/metabolismo , NADPH Oxidases/genética , NADPH Oxidases/metabolismo , Linhagem , Fagócitos/imunologia , Fagócitos/metabolismo , Fagócitos/microbiologia , Fenótipo , Fosfoproteínas/metabolismo , Prognóstico , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transdução Genética , Adulto Jovem
12.
Front Immunol ; 9: 543, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29599784

RESUMO

Activated phosphoinositide 3-kinase (PI3K) δ Syndrome (APDS), caused by autosomal dominant mutations in PIK3CD (APDS1) or PIK3R1 (APDS2), is a heterogeneous primary immunodeficiency. While initial cohort-descriptions summarized the spectrum of clinical and immunological manifestations, questions about long-term disease evolution and response to therapy remain. The prospective European Society for Immunodeficiencies (ESID)-APDS registry aims to characterize the disease course, identify outcome predictors, and evaluate treatment responses. So far, 77 patients have been recruited (51 APDS1, 26 APDS2). Analysis of disease evolution in the first 68 patients pinpoints the early occurrence of recurrent respiratory infections followed by chronic lymphoproliferation, gastrointestinal manifestations, and cytopenias. Although most manifestations occur by age 15, adult-onset and asymptomatic courses were documented. Bronchiectasis was observed in 24/40 APDS1 patients who received a CT-scan compared with 4/15 APDS2 patients. By age 20, half of the patients had received at least one immunosuppressant, but 2-3 lines of immunosuppressive therapy were not unusual before age 10. Response to rapamycin was rated by physician visual analog scale as good in 10, moderate in 9, and poor in 7. Lymphoproliferation showed the best response (8 complete, 11 partial, 6 no remission), while bowel inflammation (3 complete, 3 partial, 9 no remission) and cytopenia (3 complete, 2 partial, 9 no remission) responded less well. Hence, non-lymphoproliferative manifestations should be a key target for novel therapies. This report from the ESID-APDS registry provides comprehensive baseline documentation for a growing cohort that will be followed prospectively to establish prognostic factors and identify patients for treatment studies.


Assuntos
Síndromes de Imunodeficiência/tratamento farmacológico , Imunossupressores/uso terapêutico , Sistema de Registros , Sirolimo/uso terapêutico , Adolescente , Adulto , Criança , Pré-Escolar , Classe I de Fosfatidilinositol 3-Quinases , Europa (Continente) , Humanos , Pessoa de Meia-Idade , Sociedades Médicas , Adulto Jovem
13.
J Allergy Clin Immunol ; 142(4): 1285-1296, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29477724

RESUMO

BACKGROUND: The genetic cause of primary immunodeficiency disease (PID) carries prognostic information. OBJECTIVE: We conducted a whole-genome sequencing study assessing a large proportion of the NIHR BioResource-Rare Diseases cohort. METHODS: In the predominantly European study population of principally sporadic unrelated PID cases (n = 846), a novel Bayesian method identified nuclear factor κB subunit 1 (NFKB1) as one of the genes most strongly associated with PID, and the association was explained by 16 novel heterozygous truncating, missense, and gene deletion variants. This accounted for 4% of common variable immunodeficiency (CVID) cases (n = 390) in the cohort. Amino acid substitutions predicted to be pathogenic were assessed by means of analysis of structural protein data. Immunophenotyping, immunoblotting, and ex vivo stimulation of lymphocytes determined the functional effects of these variants. Detailed clinical and pedigree information was collected for genotype-phenotype cosegregation analyses. RESULTS: Both sporadic and familial cases demonstrated evidence of the noninfective complications of CVID, including massive lymphadenopathy (24%), unexplained splenomegaly (48%), and autoimmune disease (48%), features prior studies correlated with worse clinical prognosis. Although partial penetrance of clinical symptoms was noted in certain pedigrees, all carriers have a deficiency in B-lymphocyte differentiation. Detailed assessment of B-lymphocyte numbers, phenotype, and function identifies the presence of an increased CD21low B-cell population. Combined with identification of the disease-causing variant, this distinguishes between healthy subjects, asymptomatic carriers, and clinically affected cases. CONCLUSION: We show that heterozygous loss-of-function variants in NFKB1 are the most common known monogenic cause of CVID, which results in a temporally progressive defect in the formation of immunoglobulin-producing B cells.


Assuntos
Linfócitos B/imunologia , Imunodeficiência de Variável Comum/genética , Subunidade p50 de NF-kappa B/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Europa (Continente) , Feminino , Humanos , Lactente , Recém-Nascido , Mutação com Perda de Função , Masculino , Pessoa de Meia-Idade , Fenótipo , Linfócitos T/imunologia , Adulto Jovem
15.
Clin Immunol ; 188: 94-102, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29305966

RESUMO

The CTLA-4 checkpoint regulates the activation of T cells. Individuals with heterozygous mutations in CTLA-4 have a complex phenotype typically characterized by antibody deficiency alongside variable autoimmunity. Despite severe disease in some individuals, others remain largely unaffected with reasons for this variation unknown. We studied a large family carrying a single point mutation in CTLA-4 leading to an amino acid change R75W and compared both unaffected with affected individuals. We measured a variety of features pertaining to T cell and CTLA-4 biology and observed that at the cellular level there was complete penetrance of CTLA-4 mutations. Accordingly, unaffected individuals were indistinguishable from those with disease in terms of level of CTLA-4 expression, percentage of Treg, upregulation of CTLA-4 upon stimulation and proliferation of CD4 T cells. We conclude that the wide variation in disease phenotype is influenced by immune variation outside of CTLA-4 biology.


Assuntos
Antígenos CD28/imunologia , Antígeno CTLA-4/imunologia , Ativação Linfocitária/imunologia , Linfócitos T/imunologia , Antígenos CD28/metabolismo , Antígeno CTLA-4/deficiência , Antígeno CTLA-4/genética , Diarreia/genética , Diarreia/imunologia , Diarreia/metabolismo , Saúde da Família , Feminino , Humanos , Enteropatias/genética , Enteropatias/imunologia , Enteropatias/metabolismo , Ativação Linfocitária/genética , Masculino , Mutação de Sentido Incorreto , Linhagem , Índice de Gravidade de Doença , Transdução de Sinais/imunologia , Linfócitos T/metabolismo , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo
16.
J Allergy Clin Immunol Pract ; 6(1): 159-168.e3, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-28734862

RESUMO

BACKGROUND: Patients with common variable immunodeficiency (CVID) suffer frequent respiratory tract infections despite immunoglobulin replacement and are prescribed significant quantities of antibiotics. The clinical and microbiological nature of these exacerbations, the symptomatic triggers to take antibiotics, and the response to treatment have not been previously investigated. OBJECTIVES: To describe the nature, frequency, treatment, and clinical course of respiratory tract exacerbations in patients with CVID and to describe pathogens isolated during respiratory tract exacerbations. METHODS: We performed a prospective diary card exercise in 69 patients with CVID recruited from a primary immunodeficiency clinic in the United Kingdom, generating 6210 days of symptom data. We collected microbiology (sputum microscopy and culture, atypical bacterial PCR, and mycobacterial culture) and virology (nasopharyngeal swab multiplex PCR) samples from symptomatic patients with CVID. RESULTS: There were 170 symptomatic exacerbations and 76 exacerbations treated by antibiotics. The strongest symptomatic predictors for commencing antibiotics were cough, shortness of breath, and purulent sputum. There was a median delay of 5 days from the onset of symptoms to commencing antibiotics. Episodes characterized by purulent sputum responded more quickly to antibiotics, whereas sore throat and upper respiratory tract symptoms responded less quickly. A pathogenic virus was isolated in 56% of respiratory exacerbations and a potentially pathogenic bacteria in 33%. CONCLUSIONS: Patients with CVID delay and avoid treatment of symptomatic respiratory exacerbations, which could result in structural lung damage. However, viruses are commonly represented and illnesses dominated by upper respiratory tract symptoms respond poorly to antibiotics, suggesting that antibiotic usage could be better targeted.


Assuntos
Infecções Bacterianas/epidemiologia , Imunodeficiência de Variável Comum/epidemiologia , Nasofaringe/virologia , Infecções Respiratórias/epidemiologia , Viroses/epidemiologia , Adulto , Idoso , Antibacterianos/uso terapêutico , Infecções Bacterianas/diagnóstico , Infecções Bacterianas/tratamento farmacológico , Estudos de Coortes , Imunodeficiência de Variável Comum/tratamento farmacológico , Uso de Medicamentos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Estudos Prospectivos , Infecções Respiratórias/diagnóstico , Infecções Respiratórias/tratamento farmacológico , Escarro/microbiologia , Reino Unido/epidemiologia , Viroses/diagnóstico , Viroses/tratamento farmacológico
17.
Nat Commun ; 8(1): 1576, 2017 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-29146903

RESUMO

Dysregulation of autophagy and inflammasome activity contributes to the development of auto-inflammatory diseases. Emerging evidence highlights the importance of the actin cytoskeleton in modulating inflammatory responses. Here we show that deficiency of Wiskott-Aldrich syndrome protein (WASp), which signals to the actin cytoskeleton, modulates autophagy and inflammasome function. In a model of sterile inflammation utilizing TLR4 ligation followed by ATP or nigericin treatment, inflammasome activation is enhanced in monocytes from WAS patients and in WAS-knockout mouse dendritic cells. In ex vivo models of enteropathogenic Escherichia coli and Shigella flexneri infection, WASp deficiency causes defective bacterial clearance, excessive inflammasome activation and host cell death that are associated with dysregulated septin cage-like formation, impaired autophagic p62/LC3 recruitment and defective formation of canonical autophagosomes. Taken together, we propose that dysregulation of autophagy and inflammasome activities contribute to the autoinflammatory manifestations of WAS, thereby identifying potential targets for therapeutic intervention.


Assuntos
Citoesqueleto de Actina/metabolismo , Autofagia/imunologia , Inflamassomos/imunologia , Proteína da Síndrome de Wiskott-Aldrich/genética , Proteína da Síndrome de Wiskott-Aldrich/metabolismo , Síndrome de Wiskott-Aldrich/imunologia , Animais , Autofagia/genética , Carga Bacteriana/imunologia , Linhagem Celular Tumoral , Células Dendríticas/imunologia , Escherichia coli Enteropatogênica/imunologia , Humanos , Imunidade Inata/imunologia , Interferon Tipo I/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Monócitos/imunologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/imunologia , Nigericina/farmacologia , Septinas/metabolismo , Shigella flexneri/imunologia , Células THP-1 , Receptor 4 Toll-Like/imunologia , Síndrome de Wiskott-Aldrich/metabolismo
19.
Front Immunol ; 8: 798, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28769923

RESUMO

Mutations of the recombinase-activating genes 1 and 2 (RAG1 and RAG2) in humans are associated with a broad range of phenotypes. For patients with severe clinical presentation, hematopoietic stem cell transplantation (HSCT) represents the only curative treatment; however, high rates of graft failure and incomplete immune reconstitution have been observed, especially after unconditioned haploidentical transplantation. Studies in mice have shown that Rag-/- natural killer (NK) cells have a mature phenotype, reduced fitness, and increased cytotoxicity. We aimed to analyze NK cell phenotype and function in patients with mutations in RAG and in non-homologous end joining (NHEJ) genes. Here, we provide evidence that NK cells from these patients have an immature phenotype, with significant expansion of CD56bright CD16-/int CD57- cells, yet increased degranulation and high perforin content. Correlation was observed between in vitro recombinase activity of the mutant proteins, NK cell abnormalities, and in vivo clinical phenotype. Addition of serotherapy in the conditioning regimen, with the aim of depleting the autologous NK cell compartment, may be important to facilitate engraftment and immune reconstitution in patients with RAG and NHEJ defects treated by HSCT.

20.
Blood ; 130(11): 1327-1335, 2017 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-28716862

RESUMO

Until recently, hematopoietic stem cell transplantation was the only curative option for Wiskott-Aldrich syndrome (WAS). The first attempts at gene therapy for WAS using a ϒ-retroviral vector improved immunological parameters substantially but were complicated by acute leukemia as a result of insertional mutagenesis in a high proportion of patients. More recently, treatment of children with a state-of-the-art self-inactivating lentiviral vector (LV-w1.6 WASp) has resulted in significant clinical benefit without inducing selection of clones harboring integrations near oncogenes. Here, we describe a case of a presplenectomized 30-year-old patient with severe WAS manifesting as cutaneous vasculitis, inflammatory arthropathy, intermittent polyclonal lymphoproliferation, and significant chronic kidney disease and requiring long-term immunosuppressive treatment. Following reduced-intensity conditioning, there was rapid engraftment and expansion of a polyclonal pool of transgene-positive functional T cells and sustained gene marking in myeloid and B-cell lineages up to 20 months of observation. The patient was able to discontinue immunosuppression and exogenous immunoglobulin support, with improvement in vasculitic disease and proinflammatory markers. Autologous gene therapy using a lentiviral vector is a viable strategy for adult WAS patients with severe chronic disease complications and for whom an allogeneic procedure could present an unacceptable risk. This trial was registered at www.clinicaltrials.gov as #NCT01347242.


Assuntos
Terapia Genética , Síndrome de Wiskott-Aldrich/genética , Síndrome de Wiskott-Aldrich/terapia , Adulto , Proliferação de Células , Pré-Escolar , Ensaios Clínicos como Assunto , Células Clonais , Citocinas/sangue , Humanos , Subpopulações de Linfócitos/imunologia , Linfócitos T/imunologia , Vacinação , Síndrome de Wiskott-Aldrich/sangue
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