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1.
Haematologica ; 2020 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-31949009

RESUMO

Allogeneic hematopoietic stem cell transplantation is the treatment of choice for autosomal recessive osteopetrosis caused by defects in the TCIRG1 gene. Despite recent progress in conditioning, a relevant number of patients are not eligible for allogeneic stem cell transplantation because of the severity of the disease and significant transplant-related morbidity. We exploited peripheral CD34+ cells, known to circulate at high frequency in the peripheral blood of TCIRG1-deficient patients, as a novel cell source for autologous transplantation of gene corrected cells. Detailed phenotypical analysis showed that circulating CD34+ cells have a cellular composition that resembles bone marrow, supporting their use in gene therapy protocols. Transcriptomic profile revealed enrichment in genes expressed by hematopoietic stem and progenitor cells (HSPCs). To overcome the limit of bone marrow harvest/ HSPC mobilization and serial blood drawings in TCIRG1 patients, we applied UM171-based ex-vivo expansion of HSPCs coupled with lentiviral gene transfer. Circulating CD34+ cells from TCIRG1-defective patients were transduced with a clinically-optimized lentiviral vector (LV) expressing TCIRG1 under the control of phosphoglycerate promoter and expanded ex vivo. Expanded cells maintained long-term engraftment capacity and multi-lineage repopulating potential when transplanted in vivo both in primary and secondary NSG recipients. Moreover, when CD34+ cells were differentiated in vitro, genetically corrected osteoclasts resorbed the bone efficiently. Overall, we provide evidence that expansion of circulating HSPCs coupled to gene therapy can overcome the limit of stem cell harvest in osteopetrotic patients, thus opening the way to future gene-based treatment of skeletal diseases caused by bone marrow fibrosis.

2.
Sci Rep ; 10(1): 432, 2020 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-31949199

RESUMO

We focused on an integrated view of genomic changes in Colorectal cancer (CRC) and distant normal colon tissue (NTC) to test the effectiveness of expression profiling on identification of molecular targets. We performed transcriptome on 16 primary coupled CRC and NTC tissues. We identified pathways and networks related to pathophysiology of CRC and selected potential therapeutic targets. CRC cells have multiple ways to reprogram its transcriptome: a functional enrichment analysis in 285 genes, 25% mutated, showed that they control the major cellular processes known to promote tumorigenesis. Among the genes showing alternative splicing, cell cycle related genes were upregulated (CCND1, CDC25B, MCM2, MCM3), while genes involved in fatty acid metabolism (ACAAA2, ACADS, ACAT1, ACOX, CPT1A, HMGCS2) were downregulated. Overall 148 genes showed differential splicing identifying 17 new isoforms. Most of them are involved in the pathogenesis of CRC, although the functions of these variants remain unknown. We identified 2 in-frame fusion events, KRT19-KRT18 and EEF1A1-HSP90AB1, encoding for chemical proteins in two CRC patients. We draw a functional interactome map involving integrated multiple genomic features in CRC. Finally, we underline that two functional cell programs are prevalently deregulated and absolutely crucial to determinate and sustain CRC phenotype.

3.
Int J Med Sci ; 16(11): 1480-1491, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31673240

RESUMO

Colorectal cancer (CRC) is a leading cause of cancer death worldwide and about 20% is metastatic at diagnosis and untreatable. The anti-EGFR therapy in metastatic patients is led by the presence of KRAS-mutations in tumor tissue. KRAS-wild-type CRC patients showed a positive response rate of about 70% to cetuximab or panitumumab combined with chemotherapy. MiRNAs are promising markers in oncology and could improve our knowledge on pathogenesis and drug resistance in CRC patients. This class of molecules represents an opportunity for the development of miRNA-based strategies to overcome the ineffectiveness of anti-EGFR therapy. We performed an integrative analysis of miRNA expression profile between KRAS-mutated CRC and KRAS-wildtype CRC and paired normal colic tissue (NCT). We revealed an overexpression of miR-425-5p in KRAS-mutated CRC compared to KRAS-wild type CRC and NCT and demonstrated that miR-425-5p exerts regulatory effects on target genes involved in cellular proliferation, migration, invasion, apoptosis molecular networks. These epigenetic mechanisms could be responsible of the strong aggressiveness of KRAS-mutated CRC compared to KRAS-wildtype CRC. We proved that some miR-425-5p targeted genes are involved in EGFR tyrosine kinase inhibitor resistance pathway, suggesting that therapies based on miR-425-5p may have strong potential in targeting KRAS-driven CRC. Moreover, we demonstrated a role in the oncogenesis of miR-31-5p, miR-625-5p and miR-579 by comparing CRC versus NCT. Our results underlined that miR-425-5p might act as an oncogene to participate in the pathogenesis of KRAS-mutated CRC and contribute to increase the aggressiveness of this subcategory of CRC, controlling a complex molecular network.

4.
Int J Mol Sci ; 20(16)2019 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-31434359

RESUMO

Colorectal cancer (CRC) ranks as the most frequent carcinoma worldwide. CRC patients show strong prognostic differences and responses to treatment, and 20% have incurable metastatic disease at diagnosis. We considered it essential to investigate mechanisms that control cellular regulatory networks, such as the miRNA-mRNA interaction, known to be involved in cancer pathogenesis. We conducted a human miRNome analysis by TaqMan low density array, comparing CRC to normal colon tissue (NCT, and experimentally identified gene targets of miRNAs deregulated, by anti-correlation analysis, with the CRC whole-transcriptome profile obtained from RNASeq experiments. We identified an integrated signature of 20 deregulated miRNAs in CRC. Enrichment analyses of the gene targets controlled by these miRNAs brought to light 25 genes, members of pathways known to lead to cell growth and death (CCND1, NKD1, FZD3, MAD2L1, etc.), such as cell metabolism (ACSL6, PRPS1-2). A screening of prognosis-mediated miRNAs underlined that the overexpression of miR-224 promotes CRC metastasis, and is associated with high stage and poor survival. These findings suggest that the biology and progression of CRC depend on deregulation of multiple miRNAs that cause a complex dysfunction of cellular molecular networks. Our results have further established miRNA-mRNA interactions and defined multiple pathways involved in CRC pathogenesis.


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias Colorretais/metabolismo , MicroRNAs/metabolismo , RNA Mensageiro/metabolismo , Idoso , Biomarcadores Tumorais/genética , Neoplasias Colorretais/genética , Feminino , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica/genética , Regulação Neoplásica da Expressão Gênica/fisiologia , Redes Reguladoras de Genes/genética , Redes Reguladoras de Genes/fisiologia , Humanos , Masculino , MicroRNAs/genética , Pessoa de Meia-Idade , Prognóstico , RNA Mensageiro/genética
5.
Cardiovasc Res ; 2019 05 28.
Artigo em Inglês | MEDLINE | ID: mdl-31135876

RESUMO

AIMS: The pathogenetic mechanisms underlying unprovoked venous thromboembolism (uVTE) are largely unknown. In this study, we investigated the molecular mechanisms involved in uVTE pathogenesis by using ex-vivo expanded endothelial colony-forming cells (ECFCs), which represent a valuable non-invasive tool for the assessment of endothelial function. METHODS AND RESULTS: We isolated and expanded ECFCs from the peripheral blood of uVTE patients and observed that these cells underwent earlier senescence and showed lower growth rate compared to ECFCs obtained from healthy donors. Through microarray expression profiling, we demonstrated that 2905 genes were differentially expressed between patients and controls. Among them, the anti-angiogenic cytokine TNFSF15 and its death-receptor TNFRSF25 were up-regulated in uVTE ECFCs, and this finding was validated by RT-qPCR. TNFSF15 up-regulation was confirmed at the protein level in ECFC supernatants, and the in vivo relevance of these findings was further corroborated by demonstrating that also the plasmatic levels of TNFSF15 are increased in uVTE patients. After proving that exogenous TNFSF15 exerts pro-apoptotic and anti-proliferative activity on control ECFCs, we demonstrated through blocking experiments that TNFSF15 up-regulation contributes to impaired survival and proliferation of uVTE ECFCs. CONCLUSIONS: By providing evidence that TNFSF15 impairs ECFC functions crucial to endothelial repair, and that uVTE patients have increased TNFSF15 levels both ex-vivo and in vivo, the results of this study suggest that pathologic up-regulation of TNFSF15-TNFRSF25 axis may contribute to uVTE pathogenesis, and may represent the target for novel therapeutic strategies aimed at preventing recurrences in uVTE patients.

7.
Clin Genet ; 95(5): 607-614, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30859550

RESUMO

Crisponi/cold-induced sweating syndrome (CS/CISS) is a rare autosomal recessive disorder characterized by a complex phenotype (hyperthermia and feeding difficulties in the neonatal period, followed by scoliosis and paradoxical sweating induced by cold since early childhood) and a high neonatal lethality. CS/CISS is a genetically heterogeneous disorder caused by mutations in CRLF1 (CS/CISS1), CLCF1 (CS/CISS2) and KLHL7 (CS/CISS-like). Here, a whole exome sequencing approach in individuals with CS/CISS-like phenotype with unknown molecular defect revealed unpredicted alternative diagnoses. This approach identified putative pathogenic variations in NALCN, MAGEL2 and SCN2A. They were already found implicated in the pathogenesis of other syndromes, respectively the congenital contractures of the limbs and face, hypotonia, and developmental delay syndrome, the Schaaf-Yang syndrome, and the early infantile epileptic encephalopathy-11 syndrome. These results suggest a high neonatal phenotypic overlap among these disorders and will be very helpful for clinicians. Genetic analysis of these genes should be considered for those cases with a suspected CS/CISS during neonatal period who were tested as mutation negative in the known CS/CISS genes, because an expedited and corrected diagnosis can improve patient management and can provide a specific clinical follow-up.

8.
Am J Med Genet A ; 179(4): 634-638, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30737887

RESUMO

We report here a novel de novo missense variant affecting the last amino acid of exon 30 of CREBBP [NM_004380, c.5170G>A; p.(Glu1724Lys)] in a 17-year-old boy presenting mild intellectual disability and dysmorphisms but not resembling the phenotype of classical Rubinstein-Taybi syndrome. The patient showed a marked overweight from early infancy on and had cortical heterotopias. Recently, 22 individuals have been reported with missense mutations in the last part of exon 30 and the beginning of exon 31 of CREBBP, showing this new phenotype. This additional case further delineates the genotype-phenotype correlations within the molecular and phenotypic spectrum of variants in CREBBP and EP300.

9.
Haematologica ; 104(9): 1744-1755, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30792210

RESUMO

The balance between self-renewal and differentiation is crucial to ensure the homeostasis of the hematopoietic system, and is a hallmark of hematopoietic stem cells. However, the underlying molecular pathways, including the role of micro-RNA, are not completely understood. To assess the contribution of micro-RNA, we performed micro-RNA profiling of hematopoietic stem cells and their immediate downstream progeny multi-potent progenitors from wild-type control and Pbx1-conditional knockout mice, whose stem cells display a profound self-renewal defect. Unsupervised hierarchical cluster analysis separated stem cells from multi-potent progenitors, suggesting that micro-RNA might regulate the first transition step in the adult hematopoietic development. Notably, Pbx1-deficient and wild-type cells clustered separately, linking micro-RNAs to self-renewal impairment. Differential expression analysis of micro-RNA in the physiological stem cell-to-multi-potent progenitor transition and in Pbx1-deficient stem cells compared to control stem cells revealed miR-127-3p as the most differentially expressed. Furthermore, miR-127-3p was strongly stem cell-specific, being quickly down-regulated upon differentiation and not re-expressed further downstream in the bone marrow hematopoietic hierarchy. Inhibition of miR-127-3p function in Lineage-negative cells, achieved through a lentiviral-sponge vector, led to severe stem cell depletion, as assessed with serial transplantation assays. miR-127-3p-sponged stem cells displayed accelerated differentiation, which was uncoupled from proliferation, accounting for the observed stem cell reduction. miR-127-3p overexpression in Lineage-negative cells did not alter stem cell pool size, but gave rise to lymphopenia, likely due to lack of miR-127-3p physiological downregulation beyond the stem cell stage. Thus, tight regulation of miR-127-3p is crucial to preserve the self-renewing stem cell pool and homeostasis of the hematopoietic system.

10.
BMC Med Genet ; 20(1): 16, 2019 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-30642272

RESUMO

BACKGROUND: KBG syndrome is a very rare autosomal dominant disorder, characterized by macrodontia, distinctive craniofacial findings, skeletal findings, post-natal short stature, and developmental delays, sometimes associated with seizures and EEG abnormalities. So far, there have been over 100 cases of KBG syndrome reported. CASE PRESENTATION: Here, we describe two sisters of a non-consanguineous family, both presenting generalized epilepsy with febrile seizures (GEFS+), and one with a more complex phenotype associated with mild intellectual disability, skeletal and dental anomalies. Whole exome sequencing (WES) analysis in all the family members revealed a heterozygous SCN9A mutation, p.(Lys655Arg), shared among the father and the two probands, and a novel de novo loss of function mutation in the ANKRD11 gene, p.(Tyr1715*), in the proband with the more complex phenotype. The reassessment of the phenotypic features confirmed that the patient fulfilled the proposed diagnostic criteria for KBG syndrome, although complicated by early-onset isolated febrile seizures. EEG abnormalities with or without seizures have been reported previously in some KBG cases. The shared variant, occurring in SCN9A, has been previously found in several individuals with GEFS+ and Dravet syndrome. CONCLUSIONS: This report describe a novel de novo variant in ANKRD11 causing a mild phenotype of KGB syndrome and further supports the association of monogenic pattern of SCN9A mutations with GEFS+. Our data expand the allelic spectrum of ANKRD11 mutations, providing the first Brazilian case of KBG syndrome. Furthermore, this study offers an example of how WES has been instrumental allowing us to better dissect the clinical phenotype under study, which is a multilocus variation aggregating in one proband, rather than a phenotypic expansion associated with a single genomic locus, underscoring the role of multiple rare variants at different loci in the etiology of clinical phenotypes making problematic the diagnostic path. The successful identification of the causal variant in a gene may not be sufficient, making it necessary to identify other variants that fully explain the clinical picture. The prevalence of blended phenotypes from multiple monogenic disorders is currently unknown and will require a systematic re-analysis of large WES datasets for proper diagnosis in daily practice.


Assuntos
Anormalidades Múltiplas/genética , Doenças do Desenvolvimento Ósseo/genética , Epilepsia Generalizada/genética , Estudos de Associação Genética , Predisposição Genética para Doença , Deficiência Intelectual/genética , Mutação , Fenótipo , Proteínas Repressoras/genética , Convulsões Febris/genética , Anormalidades Dentárias/genética , Anormalidades Múltiplas/diagnóstico por imagem , Anormalidades Múltiplas/etiologia , Anormalidades Múltiplas/fisiopatologia , Adolescente , Alelos , Doenças do Desenvolvimento Ósseo/diagnóstico por imagem , Doenças do Desenvolvimento Ósseo/etiologia , Doenças do Desenvolvimento Ósseo/fisiopatologia , Brasil , Eletroencefalografia , Epilepsia Generalizada/fisiopatologia , Facies , Feminino , Loci Gênicos , Heterozigoto , Humanos , Deficiência Intelectual/diagnóstico por imagem , Deficiência Intelectual/etiologia , Deficiência Intelectual/fisiopatologia , Canal de Sódio Disparado por Voltagem NAV1.7/genética , Linhagem , Convulsões Febris/fisiopatologia , Anormalidades Dentárias/diagnóstico por imagem , Anormalidades Dentárias/etiologia , Anormalidades Dentárias/fisiopatologia , Sequenciamento Completo do Exoma
11.
Matrix Biol ; 81: 3-16, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30528862

RESUMO

Loss-of-function mutations in the gene encoding type VII collagen underlie recessive dystrophic epidermolysis bullosa (RDEB), a disease characterized by skin and mucosal blistering, impaired wound healing, and diffuse dermal inflammation and fibrosis. Transforming growth factor-ß signaling plays a crucial role in determining RDEB fibrotic microenvironment that leads to the development of disabling secondary disease manifestations, including hand and foot deformities. Experimental findings indicate that expression levels of decorin, a small leucine-rich proteoglycan and an endogenous TGF-ß inhibitor, can modulate RDEB disease phenotype by contrasting dermal fibroblast fibrotic behavior. In this study, the ability of decorin to modify RDEB course was investigated by systemically treating RDEB mice with a lentivirus expressing human decorin. Overexpressed decorin was able to enhance survival, and to limit digit contraction and the development of paw deformities. These effects were associated with decreased TGF-ß1 levels and TGF-ß signaling activation. Fibrotic traits were strongly reduced in paw skin and also attenuated in the non-chronically injured back skin. However, the expression of pro-inflammatory proteins was not decreased in both paw and back skin. Our findings confirm TGF-ß role in promoting fibrosis and disease progression in RDEB, and show that decorin counteracts disease manifestations by inhibiting TGF-ß activation. More generally, our data indicate that modifying extracellular matrix composition is an option to improve RDEB disease course.

12.
Int J Med Inform ; 120: 147-156, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30409340

RESUMO

PURPOSE: The increasing usage of high throughput sequencing in personalized medicine brings new challenges to the realm of healthcare informatics. Patient records need to accommodate data of unprecedented size and complexity as well as keep track of their production process. In this work we present a solution for integrating genomic data into electronic health records via openEHR archetypes. METHODS: We use the popular Variant Call Format as the base format to represent genetic test results within openEHR. We evaluate existing openEHR archetypes to determine what can be extended or specialized and what needs to be developed ex novo. RESULTS: Eleven new archetypes have been developed, while an existing one has been specialized to represent genomic data. We show their applicability to rare genetic diseases and compare our approach to HL7 FHIR. CONCLUSION: The proposed model allows to represent genetic test results in health records in a structured format. It supports different levels of abstraction, allowing both automated processing and clinical decision support. It is extensible via external references, allowing to keep track of data provenance and adapt to future domain changes.


Assuntos
Sistemas de Apoio a Decisões Clínicas , Registros Eletrônicos de Saúde/estatística & dados numéricos , Variação Genética , Genômica/métodos , Aplicações da Informática Médica , Modelos Teóricos , Doenças Raras/genética , Registros Eletrônicos de Saúde/organização & administração , Testes Genéticos , Genoma Humano , Humanos , Doenças Raras/diagnóstico , Doenças Raras/terapia , Integração de Sistemas
13.
Bone ; 114: 125-136, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29929043

RESUMO

Acrofrontofacionasal Dysostosis type 1 (AFFND1) is an extremely rare, autosomal recessive syndrome, comprising facial and skeletal abnormalities, short stature and intellectual disability. We analyzed an Indian family with two affected siblings by exome sequencing and identified a novel homozygous truncating mutation in the Neuroblastoma-Amplified Sequence (NBAS) gene in the patients' genome. Mutations in the NBAS gene have recently been associated with different phenotypes mainly involving skeletal formation, liver and cognitive development. The NBAS protein has been implicated in two key cellular processes, namely the non-sense mediated decay and the Golgi-to-Endoplasmic Reticulum retrograde traffic. Both functions were impaired in HEK293T cells overexpressing the truncated NBAS protein, as assessed by Real-Time PCR, Western blot analysis, co-immunoprecipitation, and immunofluorescence analysis. We examined the expression of NBAS protein in mouse embryos at various developmental stages by immunohistochemistry, and detected expression in developing chondrogenic and osteogenic structures of the skeleton as well as in the cortex, hippocampus and cerebellum, which is compatible with a role in bone and brain development. Functional genetics in the zebrafish model showed that depletion of endogenous z-nbas in fish embryos results in defective morphogenesis of chondrogenic cranial skeletal elements. Overall, our data point to a conserved function of NBAS in skeletal morphogenesis during development, support the hypothesis of a causative role of the mutated NBAS gene in the pathogenesis of AFFND1 and extend the spectrum of phenotypes associated with defects in this gene.


Assuntos
Disostose Mandibulofacial/diagnóstico por imagem , Disostose Mandibulofacial/genética , Mutação/genética , Proteínas de Neoplasias/genética , Irmãos , Animais , Animais Geneticamente Modificados , Feminino , Células HEK293 , Humanos , Lactente , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Gravidez , Peixe-Zebra
14.
Int J Med Sci ; 15(6): 536-548, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29725243

RESUMO

The clinical and genetic heterogeneity of Triple Negative Breast Cancer (TNBC) and the lack of unambiguous molecular targets contribute to the inadequacy of current therapeutic options for these variants. MicroRNAs (miRNA) are a class of small highly conserved regulatory endogenous non-coding RNA, which can alter the expression of genes encoding proteins and may play a role in the dysregulation of cellular pathways. Our goal was to improve the knowledge of the molecular pathogenesis of TNBC subgroups analyzing the miRNA expression profile, and to identify new prognostic and predictive biomarkers. We conducted a human miRNome analysis by TaqMan Low Density Array comparing different TNBC subtypes, defined by immunohistochemical basal markers EGFR and CK5/6. RT-qPCR confirmed differential expression of microRNAs. To inspect the function of the selected targets we perform Gene Ontology and KEGG enrichment analysis. We identified a single miRNA signature given by miR-135b expression level, which was strictly related to TNBC with basal-like phenotype. miR-135b target analysis revealed a role in the TGF-beta, WNT and ERBB pathways. A significant positive correlation was identified between neoplastic proliferative index and miR-135b expression. These findings confirm the oncogenic roles of miR-135b in the pathogenesis of TNBC expressing basal markers. A potential negative prognostic role of miR-135b overexpression might be related to the positive correlation with high proliferative index. Our study implies potential clinical applications: miR-135b could be a potential therapeutic target in basal-like TNBCs.


Assuntos
Biomarcadores Tumorais/genética , MicroRNAs/genética , Neoplasia de Células Basais/genética , Neoplasias de Mama Triplo Negativas/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Heterogeneidade Genética , Humanos , Estimativa de Kaplan-Meier , Pessoa de Meia-Idade , Proteínas de Neoplasias/genética , Neoplasia de Células Basais/patologia , Prognóstico , Neoplasias de Mama Triplo Negativas/classificação , Neoplasias de Mama Triplo Negativas/patologia
16.
J Allergy Clin Immunol ; 142(5): 1605-1617.e4, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-29447842

RESUMO

BACKGROUND: Wiskott-Aldrich syndrome (WAS) is a rare primary immunodeficiency caused by mutations in Wiskott-Aldrich syndrome protein (WASp), a key regulator of cytoskeletal dynamics in hematopoietic cells. A high proportion of patients experience autoimmunity caused by a breakdown in T- and B-cell tolerance. Moreover, excessive production of type I interferon (IFN-I) by plasmacytoid dendritic cells (pDCs) contributes to autoimmune signs; however, the factors that trigger excessive innate activation have not been defined. OBJECTIVE: Neutrophil extracellular traps (NETs) emerged as major initiating factors in patients with diseases such as systemic lupus erythematosus and rheumatoid arthritis. In this study we explored the possible involvement of aberrant neutrophil functions in patients with WAS. METHODS: We evaluated the expression of a set of granulocyte genes associated with NETs in a cohort of patients with WAS and the presence of NET inducers in sera. Using a mouse model of WAS, we analyzed NET release by WASp-null neutrophils and evaluated the composition and homeostasis of neutrophils in vivo. By using depletion experiments, we assessed the effect of neutrophils in promoting inflammation and reactivity against autoantigens. RESULTS: Transcripts of genes encoding neutrophil enzymes and antimicrobial peptides were increased in granulocytes of patients with WAS, and serum-soluble factors triggered NET release. WASp-null neutrophils showed increased spontaneous NETosis, induced IFN-I production by pDCs, and activated B cells through B-cell activating factor. Consistently, their depletion abolished constitutive pDC activation, normalized circulating IFN-I levels, and, importantly, abolished production of autoantibodies directed against double-stranded DNA, nucleosomes, and myeloperoxidase. CONCLUSIONS: These findings reveal that neutrophils are involved in the pathogenic loop that causes excessive activation of innate cells and autoreactive B cells, thus identifying novel mechanisms that contribute to the autoimmunity of WAS.


Assuntos
Interferon Tipo I/imunologia , Neutrófilos/imunologia , Síndrome de Wiskott-Aldrich/imunologia , Adolescente , Adulto , Animais , Autoanticorpos/imunologia , Linfócitos B/imunologia , Pré-Escolar , Células Dendríticas/imunologia , Armadilhas Extracelulares , Feminino , Expressão Gênica , Humanos , Lactente , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Síndrome de Wiskott-Aldrich/genética , Adulto Jovem
17.
J Allergy Clin Immunol ; 142(3): 928-941.e8, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29241731

RESUMO

BACKGROUND: Omenn syndrome (OS) is a rare severe combined immunodeficiency associated with autoimmunity and caused by defects in lymphoid-specific V(D)J recombination. Most patients carry hypomorphic mutations in recombination-activating gene (RAG) 1 or 2. Hematopoietic stem cell transplantation is the standard treatment; however, gene therapy (GT) might represent a valid alternative, especially for patients lacking a matched donor. OBJECTIVE: We sought to determine the efficacy of lentiviral vector (LV)-mediated GT in the murine model of OS (Rag2R229Q/R229Q) in correcting immunodeficiency and autoimmunity. METHODS: Lineage-negative cells from mice with OS were transduced with an LV encoding the human RAG2 gene and injected into irradiated recipients with OS. Control mice underwent transplantation with wild-type or OS-untransduced lineage-negative cells. Immunophenotyping, T-dependent and T-independent antigen challenge, immune spectratyping, autoantibody detection, and detailed tissue immunohistochemical analyses were performed. RESULTS: LV-mediated GT allowed immunologic reconstitution, although it was suboptimal compared with that seen in wild-type bone marrow (BM)-transplanted OS mice in peripheral blood and hematopoietic organs, such as the BM, thymus, and spleen. We observed in vivo variability in the efficacy of GT correlating with the levels of transduction achieved. Immunoglobulin levels and T-cell repertoire normalized, and gene-corrected mice responded properly to challenges in vivo. Autoimmune manifestations, such as skin infiltration and autoantibodies, dramatically improved in GT mice with a vector copy number/genome higher than 1 in the BM and 2 in the thymus. CONCLUSIONS: Our data show that LV-mediated GT for patients with OS significantly ameliorates the immunodeficiency, even in an inflammatory environment.


Assuntos
Proteínas de Ligação a DNA/genética , Terapia Genética , Lentivirus/genética , Imunodeficiência Combinada Severa/terapia , Animais , Autoimunidade , Linfócitos B/imunologia , Modelos Animais de Doenças , Feminino , Inflamação/imunologia , Inflamação/terapia , Contagem de Linfócitos , Masculino , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Imunodeficiência Combinada Severa/imunologia , Linfócitos T/imunologia
18.
Front Immunol ; 8: 490, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28512459

RESUMO

Wiskott-Aldrich syndrome (WAS) is a primary immunodeficiency caused by mutations in the gene encoding the hematopoietic-specific WAS protein (WASp). WAS is frequently associated with autoimmunity, indicating a critical role of WASp in maintenance of tolerance. The role of B cells in the induction of autoreactive immune responses in WAS has been investigated in several settings, but the mechanisms leading to the development of autoimmune manifestations have been difficult to evaluate in the mouse models of the disease that do not spontaneously develop autoimmunity. We performed an extensive characterization of Was-/- mice that provided evidence of the potential alteration in B cell selection, because of the presence of autoantibodies against double-stranded DNA, platelets, and tissue antigens. To uncover the mechanisms leading to the activation of the potentially autoreactive B cells in Was-/- mice, we performed in vivo chronic stimulations with toll-like receptors agonists (LPS and CpG) and apoptotic cells or infection with lymphocytic choriomeningitis virus. All treatments led to increased production of autoantibodies, increased proteinuria, and kidney tissue damage in Was-/- mice. These findings demonstrate that a lower clearance of pathogens and/or self-antigens and the resulting chronic inflammatory state could cause B cell tolerance breakdown leading to autoimmunity in WAS.

19.
Bone ; 97: 126-129, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28095295

RESUMO

Osteopetrosis (OPT) is a rare skeletal disorder with phenotypic and genotypic heterogeneity: a variety of clinical features besides the bony defect may be present, and at least ten different genes are known to be involved in the disease pathogenesis. In the framework of this heterogeneity, we report the clinical description of a neonate, first child of consanguineous parents, who had osteoclast-rich osteopetrosis and bone marrow failure in early life, but no other usual classical features of infantile malignant OPT, such as visual or hearing impairments. Because of the severe presentation at birth, the patient received Hematopoietic Stem Cell Transplantation (HSCT) at 2months of age with successful outcome. Post-HSCT genetic investigation by means of exome sequencing identified a novel homozygous mutation in the Fermitin Family Member 3 (FERMT3) gene, which was predicted to disrupt the functionality of its protein product kindlin 3. Our report provides information relevant to physicians for recognizing patients with one of the rarest forms of infantile malignant OPT, and clearly demonstrates that HSCT cures kindlin 3 deficiency with severe phenotype.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Proteínas de Membrana/genética , Mutação/genética , Proteínas de Neoplasias/genética , Osteopetrose/genética , Osteopetrose/terapia , Criança , Feminino , Homozigoto , Humanos , Recém-Nascido , Osteopetrose/diagnóstico por imagem , Fenótipo
20.
Front Immunol ; 8: 2015, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29434583

RESUMO

Primary immunodeficiencies with selective susceptibility to EBV infection are rare conditions associated with severe lymphoproliferation. We followed a patient, son of consanguineous parents, referred to our center for recurrent periodic episodes of fever associated with tonsillitis and adenitis started after an infectious mononucleosis and responsive to oral steroid. An initial diagnosis of periodic fever, aphthous stomatitis, pharyngitis, cervical adenitis syndrome was done. In the following months, recurrent respiratory infections and episodes of keratitis were also observed, together with a progressive reduction of immunoglobulin levels and an increase of CD20+ cells. Cell sorting and EBV PCR showed 25,000 copies for 100,000 leukocytes with predominant infection of B lymphocytes. Lymph node's biopsy revealed reactive lymphadenopathy with paracortical involvement consistent with a chronic EBV infection. Molecular analysis of XIAP, SHA2D1A, ITK, and CD27 genes did not detect any pathogenic mutation. The patients underwent repeated courses of anti-CD20 therapy with only a partial control of the disease, followed by stem cell transplantation with a complete normalization of clinical and immunological features. Whole exome sequencing of the trio was performed. Among the variants identified, a novel loss of function homozygous c.163-2A>G mutation of the CD70 gene, affecting the exon 2 AG-acceptor splice site, fit the expected recessive model of inheritance. Indeed, deficiency of both CD27, and, more recently, of its ligand CD70, has been reported as a cause of EBV-driven lymphoproliferation and hypogammaglobulinemia. Cell surface analysis of patient-derived PHA-T cell blasts and EBV-transformed lymphoblastoid cell lines confirmed absence of CD70 expression. In conclusion, we describe a case of severe chronic EBV infection caused by a novel mutation of CD70 presenting with recurrent periodic fever.

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