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1.
Article in English | MEDLINE | ID: mdl-38804143

ABSTRACT

BACKGROUND: Carbapenem-resistant Pseudomonas aeruginosa are being increasingly described worldwide. Here, we investigated the molecular mechanisms underlying carbapenem resistance in an extremely drug-resistant P. aeruginosa isolate from a neonatal intensive care unit in Morocco. MATERIALS AND METHODS: P. aeruginosa strain O82J1 was identified using MALDI-TOF-MS. Carba NP, immunochromatographic assay NG Carba5 and antimicrobial susceptibility testing using disc diffusion and microbroth were performed. Whole-genome sequencing using the Illumina and MinION technologies and different software packages available at the Center of Genomic Epidemiology were used to predict the resistome, sequence type and plasmid types. RESULTS: P. aeruginosa O82J1 co-expressed two metallo-ß-lactamases, blaNDM-1 and blaVIM-2, and was susceptible to colistin and apramycin only. It belonged to ST773 that is frequently reported worldwide as a high-risk P. aeruginosa clone. The blaVIM-2 gene was integron-borne on a IncP-2 465-kb plasmid, whereas the blaNDM-1 gene was chromosomally encoded and embedded in an integrative conjugative element, probably at the origin of its acquisition. A total of 23 antimicrobial resistance genes were detected including a blaPER-1 ESBL gene, and an 16S-rRNA methyltransferase gene rmtB. CONCLUSIONS: The isolation of XDR P. aeruginosa isolates expressing several carbapenemases in a neonatal intensive care unit is of great concern due to the reduced treatment options, relying only on colistin, but not recommended in neonates, and apramycin, not yet approved for human therapy. Concerns were further elevated due to the resistance to cefiderocol and ATM/AVI, two novel and last-resort antibiotics recommended to treat infections caused by Gram-negative bacteria, particularly XDR P. aeruginosa in adults.

3.
Microorganisms ; 12(3)2024 Mar 05.
Article in English | MEDLINE | ID: mdl-38543576

ABSTRACT

Abscesses represent the most prominent emerging problem in the red meat industry, leading to great economic constraints and public health hazards. Data on etiological agents present in these purulent lesions in Algeria are very scarce. The aim of this study was to identify the bacteria responsible for these abscesses and to determine their antibiotic susceptibility profiles. A total of 123 samples of abscesses from 100 slaughtered sheep and 23 slaughtered cattle were cultured in several media. A total of 114 bacterial isolates were cultured from 103 abscesses. Bacteria were identified using MALDI-TOF, and antibiotic susceptibility was determined by the disk diffusion method on Mueller-Hinton agar. A total of 73.6% (n = 84) corresponded to Enterobacterales, of which four were multidrug-resistant (MDR). These isolates, together with Staphylococcus aureus, coagulase negative Staphylococci, and seven randomly chosen susceptible Escherichia coli isolates, were further characterized using WGS. Resistome analysis of the four MDR Enterobacterales isolates revealed the presence of OXA-48 carbapenemase in two Klebsiella pneumoniae ST985 and one E. coli ST10 isolates and a CTX-M-15 ESBL in one E. coli isolate ST1706. Two coagulase-negative Staphylococci isolates were found to carry the mecA gene. WGS showed the presence of different resistance genes and virulence genes. Our study revealed 5% of MDR Enterobacterales (including ESBLs and carbapenemases) identified from abscesses, thus urging the need for abscess monitoring in slaughterhouses.

4.
Eur J Endocrinol ; 190(2): 173-181, 2024 Feb 01.
Article in English | MEDLINE | ID: mdl-38330165

ABSTRACT

IMPORTANCE: A paradoxical increase of growth hormone (GH) following oral glucose load has been described in ∼30% of patients with acromegaly and has been related to the ectopic expression of the glucose-dependent insulinotropic polypeptide (GIP) receptor (GIPR) in somatotropinomas. Recently, we identified germline pathogenic variants and somatic loss of heterozygosity of lysine demethylase 1A (KDM1A) in patients with GIP-dependent primary bilateral macronodular adrenal hyperplasia with Cushing's syndrome. The ectopic expression of GIPR in both adrenal and pituitary lesions suggests a common molecular mechanism. OBJECTIVE: We aimed to analyze KDM1A gene sequence and KDM1A and GIPR expressions in somatotroph pituitary adenomas. SETTINGS: We conducted a cohort study at university hospitals in France and in Italy. We collected pituitary adenoma specimens from acromegalic patients who had undergone pituitary surgery. We performed targeted exome sequencing (gene panel analysis) and array-comparative genomic hybridization on somatic DNA derived from adenomas and performed droplet digital PCR on adenoma samples to quantify KDM1A and GIPR expressions. RESULTS: One hundred and forty-six patients with sporadic acromegaly were studied; 72.6% presented unsuppressed classical GH response, whereas 27.4% displayed a paradoxical rise in GH after oral glucose load. We did not identify any pathogenic variant in the KDM1A gene in the adenomas of these patients. However, we identified a recurrent 1p deletion encompassing the KDM1A locus in 29 adenomas and observed a higher prevalence of paradoxical GH rise (P = .0166), lower KDM1A expression (4.47 ± 2.49 vs 8.56 ± 5.62, P < .0001), and higher GIPR expression (1.09 ± 0.92 vs 0.43 ± 0.51, P = .0012) in adenomas from patients with KDM1A haploinsufficiency compared with those with 2 KDM1A copies. CONCLUSIONS AND RELEVANCE: Unlike in GIP-dependent primary bilateral macronodular adrenal hyperplasia, KDM1A genetic variations are not the cause of GIPR expression in somatotroph pituitary adenomas. Recurrent KDM1A haploinsufficiency, more frequently observed in GIPR-expressing adenomas, could be responsible for decreased KDM1A function resulting in transcriptional derepression on the GIPR locus.


Subject(s)
Acromegaly , Adenoma , Growth Hormone-Secreting Pituitary Adenoma , Human Growth Hormone , Pituitary Neoplasms , Somatotrophs , Humans , Pituitary Neoplasms/pathology , Acromegaly/metabolism , Somatotrophs/metabolism , Somatotrophs/pathology , Comparative Genomic Hybridization , Hyperplasia/pathology , Cohort Studies , Genotype , Growth Hormone-Secreting Pituitary Adenoma/metabolism , Adenoma/pathology , Human Growth Hormone/metabolism , Growth Hormone/metabolism , Glucose , Histone Demethylases/genetics , Histone Demethylases/metabolism
5.
Genes (Basel) ; 13(11)2022 11 20.
Article in English | MEDLINE | ID: mdl-36421840

ABSTRACT

Disease-associated pathogenic variants in the A-Kinase Anchor Protein 9 (AKAP9) (MIM *604001) have been recently identified in patients with autosomal dominant long QT syndrome 11 (MIM #611820), lethal arrhythmia (ventricular fibrillation, polymorphic ventricular tachycardia), Brugada syndrome, and sudden unexpected death. However, AKAP9 sequence variations were rarely reported and AKAP9 was classified as a "disputed evidence" gene to support disease causation due to the insufficient genetic evidence and a limited number of reported AKAP9-mutated patients. Here, we describe a 47-year-old male carrying a novel frameshift AKAP9 pathogenic variant who presented recurrent syncopal attacks and sudden cardiac arrest that required a semi-automatic external defibrillator implant and an electric shock treatment of ventricular arrhythmia. This study provides insight into the mechanism underlying cardiac arrest and confirms that AKAP9 loss-of-function variants predispose to serious, life-threatening ventricular arrhythmias.


Subject(s)
Brugada Syndrome , Channelopathies , Male , Humans , Middle Aged , Channelopathies/complications , A Kinase Anchor Proteins/genetics , Death, Sudden, Cardiac/etiology , Arrhythmias, Cardiac/genetics , Brugada Syndrome/genetics , Cytoskeletal Proteins
6.
Clin Chem ; 68(2): 313-321, 2022 02 01.
Article in English | MEDLINE | ID: mdl-34871369

ABSTRACT

BACKGROUND: To date, the usage of Galaxy, an open-source bioinformatics platform, has been reported primarily in research. We report 5 years' experience (2015 to 2020) with Galaxy in our hospital, as part of the "Assistance Publique-Hôpitaux de Paris" (AP-HP), to demonstrate its suitability for high-throughput sequencing (HTS) data analysis in a clinical laboratory setting. METHODS: Our Galaxy instance has been running since July 2015 and is used daily to study inherited diseases, cancer, and microbiology. For the molecular diagnosis of hereditary diseases, 6970 patients were analyzed with Galaxy (corresponding to a total of 7029 analyses). RESULTS: Using Galaxy, the time to process a batch of 23 samples-equivalent to a targeted DNA sequencing MiSeq run-from raw data to an annotated variant call file was generally less than 2 h for panels between 1 and 500 kb. Over 5 years, we only restarted the server twice for hardware maintenance and did not experience any significant troubles, demonstrating the robustness of our Galaxy installation in conjunction with HTCondor as a job scheduler and a PostgreSQL database. The quality of our targeted exome sequencing method was externally evaluated annually by the European Molecular Genetics Quality Network (EMQN). Sensitivity was mean (SD)% 99 (2)% for single nucleotide variants and 93 (9)% for small insertion-deletions. CONCLUSION: Our experience with Galaxy demonstrates it to be a suitable platform for HTS data analysis with vast potential to benefit patient care in a clinical laboratory setting.


Subject(s)
Computational Biology , Laboratories, Clinical , Computational Biology/methods , High-Throughput Nucleotide Sequencing/methods , Humans , Sequence Analysis, DNA , Software
7.
Lancet Diabetes Endocrinol ; 9(12): 813-824, 2021 12.
Article in English | MEDLINE | ID: mdl-34655521

ABSTRACT

BACKGROUND: GIP-dependent primary bilateral macronodular adrenal hyperplasia with Cushing's syndrome is caused by aberrant expression of the GIP receptor in adrenal lesions. The bilateral nature of this disease suggests germline genetic predisposition. We aimed to identify the genetic driver event responsible for GIP-dependent primary bilateral macronodular adrenal hyperplasia with Cushing's syndrome. METHODS: We conducted a multicentre, retrospective, cohort study at endocrine hospitals and university hospitals in France, Canada, Italy, Greece, Belgium, and the Netherlands. We collected blood and adrenal samples from patients who had undergone unilateral or bilateral adrenalectomy for GIP-dependent primary bilateral macronodular adrenal hyperplasia with Cushing's syndrome. Adrenal samples from patients with primary bilateral macronodular adrenal hyperplasia who had undergone an adrenalectomy for overt or mild Cushing's syndrome without evidence of food-dependent cortisol production and those with GIP-dependent unilateral adrenocortical adenomas were used as control groups. We performed whole genome, whole exome, and targeted next generation sequencing, and copy number analyses of blood and adrenal DNA from patients with familial or sporadic disease. We performed RNA sequencing on adrenal samples and functional analyses of the identified genetic defect in the human adrenocortical cell line H295R. FINDINGS: 17 patients with GIP-dependent primary bilateral macronodular adrenal hyperplasia with Cushing's syndrome were studied. The median age of patients was 43·3 (95% CI 38·8-47·8) years and most patients (15 [88%]) were women. We identified germline heterozygous pathogenic or most likely pathogenic variants in the KDM1A gene in all 17 patients. We also identified a recurrent deletion in the short p arm of chromosome 1 harboring the KDM1A locus in adrenal lesions of these patients. None of the 29 patients in the control groups had KDM1A germline or somatic alterations. Concomitant genetic inactivation of both KDM1A alleles resulted in loss of KDM1A expression in adrenal lesions. Global gene expression analysis showed GIP receptor upregulation with a log2 fold change of 7·99 (95% CI 7·34-8·66; p=4·4 × 10-125), and differential regulation of several other G protein-coupled receptors in GIP-dependent primary bilateral macronodular hyperplasia samples compared with control samples. In vitro pharmacological inhibition and inactivation of KDM1A by CRISPR-Cas9 genome editing resulted in an increase of GIP receptor transcripts and protein in human adrenocortical H295R cells. INTERPRETATION: We propose that GIP-dependent primary bilateral macronodular adrenal hyperplasia with Cushing's syndrome results from a two-hit inactivation of KDM1A, consistent with the tumour suppressor gene model of tumorigenesis. Genetic testing and counselling should be offered to these patients and their relatives. FUNDING: Agence Nationale de la Recherche, Fondation du Grand défi Pierre Lavoie, and the French National Cancer Institute.


Subject(s)
Cushing Syndrome , Adrenal Glands/pathology , Adult , Cohort Studies , Cushing Syndrome/complications , Female , Histone Demethylases/metabolism , Humans , Hydrocortisone/metabolism , Hyperplasia/complications , Male , Middle Aged , Retrospective Studies
8.
Front Microbiol ; 12: 741972, 2021.
Article in English | MEDLINE | ID: mdl-34987484

ABSTRACT

The differential expression of VIM-1 in Atlantibacter hermannii WEB-2 and Enterobacter hormaechei ssp. hoffmannii WEB-1 clinical isolates from a rectal swab of a hospitalized patient in France was investigated. A. hermannii WEB-2 was resistant to all ß-lactams except carbapenems. It produced ESBL SHV-12, but the Carba NP test failed to detect any carbapenemase activity despite the production of VIM-1. Conversely, E. hormaechei WEB-1, previously recovered from the same patient, was positive for the detection of carbapenemase activity. The bla VIM-1 gene was located on a plasmid and embedded within class 1 integron. Both plasmids were of the same IncA incompatibility group and conferred the same resistance pattern when electroporated in Escherichia coli TOP10 or Enterobacter cloacae CIP7933. Quantitative RT-PCR experiments indicated a weaker replication of pWEB-2 in A. hermannii as compared to E. hormaechei. An isogenic mutant of A. hermannii WEB-2 selected after sequential passages with increased concentrations of imipenem possessed higher MICs for carbapenems and cephalosporins including cefiderocol, higher levels of the bla VIM-1 gene transcripts, and detectable carbapenemase activity using the Carba NP test. Assessment of read coverage demonstrated that a duplication of the region surrounding bla VIM-1 gene occurred in the A. hermannii mutant with detectable carbapenemase activity. The lack of detection of the VIM-1 carbapenemase activity in A. hermannii WEB-2 isolate was likely due to a weak replication of the IncA plasmid harboring the bla VIM-1 gene. Imipenem as selective pressure led to a duplication of this gene on the plasmid and to the restoration of a significant carbapenem-hydrolyzing phenotype.

9.
Papillomavirus Res ; 8: 100169, 2019 12.
Article in English | MEDLINE | ID: mdl-31283993

ABSTRACT

The linear reverse blotting assays are valid methods for accurate human papillomavirus (HPV) typing required to manage women at risk of developing cervical cancer. However, some samples showed a positive signal in HPV lines but failed to display a positive signal in subsequent typing lines (designated as HPV-X), which indicate that certain types were not available on the respective typing blots. The aim of this study is to elucidate the types or variants of HPV through the high-throughput sequencing (HTS) of 54 ASCUS cervical samples in which the viruses remained untypeable with INNO LiPA HPV® assays. Low-risk (LR)-HPV types (HPV6, 30, 42, 62, 67, 72, 74, 81, 83, 84, 87, 89, 90 and 114), high-risk (HR)-HPV35 and possibly (p)HR-HPV73 were detected among HPV-X. Individual multiple infections (two to seven types) were detected in 40.7% of samples. Twenty-two specimens contained variants characterised by 2-10 changes. HPV30 reached the maximal number of 17 variants with relative abundance inferior or equal to 2.7%. The presence of L1 quasispecies explains why linear reverse blotting assays fail when variants compete or do not match the specific probes. Further studies are needed to measure the LR-HPV quasispecies dynamics and its role during persistent infection.


Subject(s)
Cervix Uteri/virology , Genetic Variation , High-Throughput Nucleotide Sequencing , Papillomaviridae/genetics , Papillomavirus Infections/virology , Quasispecies/genetics , Base Sequence , DNA, Viral , Female , Genotype , Humans , Molecular Typing , Papillomaviridae/classification , Papillomavirus Infections/complications , Phylogeny , Sequence Analysis, DNA , Uterine Cervical Neoplasms/diagnosis , Uterine Cervical Neoplasms/etiology
10.
Eur J Med Genet ; 61(6): 322-328, 2018 Jun.
Article in English | MEDLINE | ID: mdl-29366875

ABSTRACT

Proximal 19p13.12 microdeletion has been rarely reported. Only five postnatal cases with intellectual disability, facial dysmorphism, branchial arch defects and overlapping deletions involving proximal 19p13.12 have been documented. Two critical intervals were previously defined: a 700 kb for branchial arch defects and a 350 kb for hypertrichosis-synophrys-protruding front teeth. We describe the first prenatal case, a fetal death in utero at 39 weeks of gestation. Agilent 180K array-CGH analysis identified a heterozygous interstitial 745 kb deletion at 19p13.12 chromosome region, encompassing both previously reported critical intervals, including at least 6 functionally relevant genes: NOTCH3, SYDE1, AKAP8, AKAP8L, WIZ and BRD4. Quantitative PCR showed that the deletion occurred de novo with a median size of 753 kb. NOTCH3 and SYDE1 were candidate genes for placental pathology whilst AKAP8, AKAP8L, WIZ and BRD4 were highly expressed in the branchial arches. Molecular characterization and sequencing of candidate genes for placental pathology and branchial arch defects were carried out in order to correlate the genotype-phenotype relationship and unravel the underlying mechanism of proximal 19p13.12 microdeletion syndrome. This case also contributes to define the novel critical interval and expand the clinical phenotype spectrum of proximal 19p13.12 microdeletion syndrome.


Subject(s)
Chromosome Deletion , Chromosomes, Human, Pair 19 , Fetal Diseases/diagnosis , Fetal Diseases/genetics , Abnormalities, Multiple/genetics , Adult , Branchial Region/abnormalities , Comparative Genomic Hybridization , Female , Fetal Death , Genotype , Heterozygote , Humans , Intellectual Disability/genetics , Phenotype , Polymerase Chain Reaction , Pregnancy , Pregnancy Trimester, Third , Prenatal Diagnosis , Syndrome
11.
Exp Hematol ; 53: 48-58, 2017 09.
Article in English | MEDLINE | ID: mdl-28602946

ABSTRACT

We report here the first use of whole-genome sequencing (WGS) to examine the initial clonal dynamics in an unusual patient with chronic myeloid leukemia (CML), who presented in chronic phase (CP) with doubly marked BCR-ABL1+/JAK2V617F-mutant cells and, over a 9-year period, progressed into an accelerated phase (AP) and then terminal blast phase (BP). WGS revealed that the diagnostic cells also contained mutations in ASXL1, SEC23B, MAD1L1, and RREB1 as well as 12,000 additional uncommon DNA variants. WGS of endothelial cells generated from circulating precursors revealed many of these were shared with the CML clone. Surprisingly, WGS of induced pluripotent stem cells (iPSCs) derived from the AP cells revealed only six additional coding somatic mutations, despite retention by the hematopoietic progeny of the parental AP cell levels of BCR-ABL1 expression and sensitivity to imatinib and pimozide. Limited analysis of BP cells revealed independent subclonal progression to homozygosity of the MAD1L1 and RREB1 variants. MAD1L1 and SEC23B mutations were also identified in 2 of 101 cases of myeloproliferative neoplasms, but not in 42 healthy subjects. These findings challenge historic concepts of clonal evolution in CML.


Subject(s)
Janus Kinase 2/genetics , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/genetics , Mutation , Cell Cycle Proteins/genetics , DNA-Binding Proteins/genetics , Genome-Wide Association Study , Humans , Induced Pluripotent Stem Cells/physiology , Male , Middle Aged , Nuclear Proteins/genetics , Transcription Factors/genetics
13.
Retrovirology ; 9: 43, 2012 May 25.
Article in English | MEDLINE | ID: mdl-22632376

ABSTRACT

BACKGROUND: Conflicting results regarding changes in mucosal IgA production or in the proportions of IgA plasma cells in the small and large intestines during HIV-infection have been previously reported. Except in individuals repeatedly exposed to HIV-1 but yet remaining uninfected, HIV-specific IgAs are frequently absent in mucosal secretions from HIV-infected patients. However, little is known about the organization and functionality of mucosal B-cell follicles in acute HIV/SIV infection during which a T-dependent IgA response should have been initiated. In the present study, we evaluated changes in B-cell and T-cell subsets as well as the extent of apoptosis and class-specific plasma cells in Peyer's Patches, isolated lymphoid follicles, and lamina propria. Plasma levels of IgA, BAFF and APRIL were also determined. RESULTS: Plasma IgA level was reduced by 46% by 28 days post infection (dpi), and no IgA plasma cells were found within germinal centers of Peyer's Patches and isolated lymphoid follicles. This lack of a T-dependent IgA response occurs although germinal centers remained functional with no sign of follicular damage, while a prolonged survival of follicular CD4+ T-cells and normal generation of IgG plasma cells is observed. Whereas the average plasma BAFF level was increased by 4.5-fold and total plasma cells were 1.7 to 1.9-fold more numerous in the lamina propria, the relative proportion of IgA plasma cells in this effector site was reduced by 19% (duodemun) to 35% (ileum) at 28 dpi. CONCLUSION: Our data provide evidence that SIV is unable to initiate a T-dependent IgA response during the acute phase of infection and favors the production of IgG (ileum) or IgM (duodenum) plasma cells at the expense of IgA plasma cells. Therefore, an early and generalized default in IgA production takes place during the acute of phase of HIV/SIV infection, which might impair not only the virus-specific antibody response but also IgA responses to other pathogens and vaccines as well. Understanding the mechanisms that impair IgA production during acute HIV/SIV infection is crucial to improve virus-specific response in mucosa and control microbial translocation.


Subject(s)
Acquired Immunodeficiency Syndrome/immunology , Antibody Formation , Immunoglobulin A/immunology , Intestinal Mucosa/immunology , Plasma Cells/immunology , Simian Immunodeficiency Virus/immunology , Acquired Immunodeficiency Syndrome/virology , Animals , Apoptosis , B-Cell Activating Factor/immunology , B-Lymphocyte Subsets/immunology , B-Lymphocyte Subsets/virology , Cell Survival , Immunohistochemistry , Intestinal Mucosa/virology , Macaca fascicularis , Male , Peyer's Patches/immunology , Peyer's Patches/virology , RNA, Viral/analysis , Simian Immunodeficiency Virus/pathogenicity , T-Lymphocyte Subsets/immunology , T-Lymphocyte Subsets/virology , Tumor Necrosis Factor Ligand Superfamily Member 13/immunology , Viral Load
14.
Asian Pac J Allergy Immunol ; 30(1): 71-8, 2012 Mar.
Article in English | MEDLINE | ID: mdl-22523910

ABSTRACT

BACKGROUND: The Wiskott-Aldrich syndrome (WAS) is a rare X-linked immunodeficiency disorder characterized by thrombocytopenia with small sized platelets, eczema, and recurrent infections. There is paucity of information on WAS from the Indian subcontinent. We describe the clinical and molecular profile of 8 patients with WAS as seen in the Pediatric Immunodeficiency Clinic at the Advanced Pediatrics Centre, Postgraduate Institute of Medical Education and Research, Chandigarh, India. METHODS: A detailed analysis of the clinical profiles, investigations and outcome of the 8 children diagnosed with WAS during the period 2006- 2010 was performed. Confirmation of the genetic diagnosis was done at the Service d'Hématologie, d'Immunologie et de Cytogénétique, Hôpital de Bicêtre, Le Kremlin-Bicêtre, France and the National Defense Medical College, Saitama, Japan. RESULTS: 8 patients were diagnosed as WAS in 5 years. The ages at diagnosis ranged from 13 weeks to 9 years while the mean age of onset of the symptoms was 117 days +/- 136 days. The diagnosis was established within a mean period of 31 months (ranging 1-108 months) from the onset of symptoms. Recurrent infections and diarrhea were seen in 6 and 7 out of the 8 patients, respectively, while eczema was variable. Autoimmunity manifestations were observed in 2 children. Thrombocytopenia and small platelet size was the hallmark of the disease and the main clinical clue to diagnosis in our patients. Mutations in the WASP gene were seen in 8 children, out of which 2 were novel mutations. While one child successfully underwent bone marrow transplantation, two children are doing well on immunoglobulin replacement and cotrimoxazole prophylaxis. Out of 8 children 4 children in our cohort died--all had high WAS scores and could not be offered hematopoietic stem cell transplantation. CONCLUSION: WAS should be suspected clinically in any male infant with persistent unexplained thrombocytopenia and especially if the platelet size is small. Clinical presentation can be very variable and it is therefore important to recognize the entire spectrum of the disease. Understanding the molecular basis has important implications for the diagnosis, treatment, and genetic counseling of patients with WAS.


Subject(s)
Wiskott-Aldrich Syndrome/diagnosis , Wiskott-Aldrich Syndrome/genetics , Child , Child, Preschool , Humans , India , Infant , Male , Wiskott-Aldrich Syndrome/immunology
15.
Am J Pathol ; 179(4): 1630-7, 2011 Oct.
Article in English | MEDLINE | ID: mdl-21871426

ABSTRACT

Posttransplantation lymphoproliferative disorders (PTLD) are associated with Epstein-Barr virus (EBV) and activate the NF-κB pathway. B-cell activating factor (BAFF) modulates cell growth and survival in non-Hodgkin's lymphomas. However, there are few studies of EBV, BAFF/BAFF-R signaling, and NF-κB1 and NF-κB2 pathway activation in PTLD. Diffuse large B-cell lymphomas (DLBCL) in two different clinical contexts, immunocompetent patients (DLBCL/IC; n = 30) or posttransplantation solid-organ recipients (DLBCL/PTLD; n = 21), were characterized histogenically as germinal center (GC) or non-germinal center (NGC). Expression of BAFF, BAFF-R, and NF-κB proteins p50 and p52 and the presence or absence of EBV were compared in these clinical contexts. Regardless of the GC or NGC pattern of DLBCL, BAFF-R was expressed in 37% of DLBCL/IC but in only 4.8% of DLBCL/PTLD. p52 was expressed in DLBCL/PTLD/NGC (12 of 19 cases) as compared with DLBCL/IC/NGC (0 of 18 cases). This pattern might be related to the presence of EBV and latent membrane protein 1 because p52 expression was observed primarily in EBV-positive DLBCL/PTLD cases expressing latent membrane protein 1. Thus, the activation profile or NGC pattern of DLBCL/PTLD was not associated with BAFF/BAFF-R expression, whereas nuclear p52 related to NF-κB2 pathway activation might be linked to EBV.


Subject(s)
B-Cell Activation Factor Receptor/metabolism , Lymphoma, Large B-Cell, Diffuse/etiology , Lymphoma, Large B-Cell, Diffuse/metabolism , Lymphoproliferative Disorders/etiology , Lymphoproliferative Disorders/metabolism , NF-kappa B p52 Subunit/metabolism , Transplantation/adverse effects , Adolescent , Adult , Aged , Aged, 80 and over , B-Cell Activating Factor/metabolism , Child, Preschool , Female , Herpesvirus 4, Human/isolation & purification , Humans , Immunohistochemistry , Infant , Lymphoma, Large B-Cell, Diffuse/pathology , Lymphoma, Large B-Cell, Diffuse/virology , Lymphoproliferative Disorders/pathology , Lymphoproliferative Disorders/virology , Male , Middle Aged , Signal Transduction
16.
Eur J Haematol ; 87(4): 366-71, 2011 Oct.
Article in English | MEDLINE | ID: mdl-21711396

ABSTRACT

Several pediatric patients showing symptoms consistent with the Wiskott-Aldrich syndrome (WAS) were referred to us and turned out to display the c.273+11dup change in the WAS gene. It consisted of the insertion of one C in an unusual tract of 7C near the intron 2 donor splicing site of the WAS gene. In the patients, non-synonymous WAS mutations were found twice only and one mutation was elucidated in RUNX1. In the absence of a non-synonymous mutation in the WAS gene, the c.273+11dup change affected neither the levels nor the sequence of WAS mRNA. In the presence of a non-synonymous WAS mutation, the c.273+11dup alteration failed to worsen the expected phenotype. Minor splicing abnormalities concerning exon 10 were observed both in WAS patients, and in healthy individuals carrying or not carrying the c.273+11dup. The c.273+11dup change was encountered four times in 107 normal male and female controls (172 alleles tested: 2.3%), and eight times in a series of 248 male patients (248 alleles tested: 3.2%). We conclude that the presence of the additional C in the WAS gene is a functionally neutral polymorphism.


Subject(s)
Gene Duplication , Polymorphism, Genetic , Wiskott-Aldrich Syndrome Protein/genetics , Base Sequence , DNA Primers , Humans , Introns , Mutation
17.
J Virol ; 85(13): 6502-12, 2011 Jul.
Article in English | MEDLINE | ID: mdl-21507981

ABSTRACT

Transforming growth factor beta 1 (TGF-ß1) signal transduction has been implicated in many second-messenger pathways, including the NF-κB pathway. We provide evidence of a novel TGF-ß1-mediated pathway that leads to extracellular signal-regulated kinase (ERK) 1/2 phosphorylation, which in turn induces expression of an Epstein-Barr virus (EBV) protein, ZEBRA, that is responsible for the induction of the viral lytic cycle. This pathway includes two unexpected steps, both of which are required to control ERK 1/2 phosphorylation: first, a quick and transient activation of NF-κB, and second, downregulation of inducible nitric oxide synthase (iNOS) activity that requires the participation of NF-κB activity. Although necessary, NF-κB alone is not sufficient to produce downregulation of iNOS, suggesting that another uncharacterized event(s) is involved in this pathway. Dissection of the steps involved in the switch from the EBV latent cycle to the lytic cycle will be important to understand how virus-host relationships modulate the innate immune system.


Subject(s)
Down-Regulation , Herpesvirus 4, Human/physiology , NF-kappa B/metabolism , Nitric Oxide Synthase Type II/metabolism , Transforming Growth Factor beta1/metabolism , Virus Activation , B-Lymphocytes/virology , Cell Line , Cell Line, Transformed , Gene Expression Regulation , Gene Expression Regulation, Viral , Herpesvirus 4, Human/genetics , Herpesvirus 4, Human/metabolism , Humans , Mitogen-Activated Protein Kinase 1/genetics , Mitogen-Activated Protein Kinase 1/metabolism , Mitogen-Activated Protein Kinase 3/genetics , Mitogen-Activated Protein Kinase 3/metabolism , NF-kappa B/genetics , Nitric Oxide/biosynthesis , Nitric Oxide Synthase Type II/genetics , Trans-Activators/genetics , Trans-Activators/metabolism
18.
Pediatr Blood Cancer ; 56(7): 1130-2, 2011 Jul 01.
Article in English | MEDLINE | ID: mdl-21488159

ABSTRACT

We report two unusual presenting manifestations of Wiskott-Aldrich syndrome (WAS), recurrent acute hemorrhagic edema of infancy (AHEI); a form of cutaneous vasculitis and hyperostosis of the tibia. Though cutaneous vasculitis is known to occur in WAS, presentation in early infancy and as AHEI is extremely uncommon. Hyperostosis is not a well-recognized association in WAS; only three patients with this association have been previously reported. In our patient these two unusual manifestations preceded the onset of recurrent infections. Recognition of this rare presentation led us to an early diagnosis of WAS, associated with p.Glu31Lys mutation in the WAS protein.


Subject(s)
Edema/etiology , Hemorrhage/etiology , Hyperostosis/etiology , Tibia/pathology , Vasculitis, Leukocytoclastic, Cutaneous/etiology , Wiskott-Aldrich Syndrome/complications , Edema/pathology , Hemorrhage/pathology , Humans , Hyperostosis/pathology , Infant, Newborn , Male , Recurrence , Vasculitis, Leukocytoclastic, Cutaneous/pathology , Wiskott-Aldrich Syndrome/pathology
19.
Pediatrics ; 127(2): e498-504, 2011 Feb.
Article in English | MEDLINE | ID: mdl-21262885

ABSTRACT

Aortic aneurysms are a rare condition in children. Here we report the occurrence of aortic aneurysms in 5 children with Wiskott-Aldrich syndrome (WAS). Three patients had a WAS score of 4, and 2 patients had a WAS score of 5, but autoimmunity was only present in 1 patient. Discovery was fortuitous in 4 cases after chest radiography or thoracic or abdominal computed tomography, which was performed to investigate unrelated symptoms; in 1 patient, thoracic pain was an alerting sign. Age at diagnosis was 10 to 16 years. Aneurysms were confined to the thoracic aorta in 4 cases and to the abdominal aorta in 1 case and were from 2 to 6 cm in size. Aortic surgery was successfully performed on the single symptomatic patient. Two other patients are alive: there has been a low progression of the aneurysm 15 years after hematopoietic stem cell transplantation in 1 patient and no evidence of progression after 12 years of follow-up without hematopoietic stem cell transplantation in the second patient. Two patients died 2 and 4 years after diagnosis from unrelated complications. A systematic retrospective search of 33 other patients with WAS for whom imaging material was available did not reveal the presence of aortic aneurysms. This unusual frequency of aortic aneurysm found in patients with WAS (5 of 38) indicates that aneurysm can be an underdiagnosed complication of WAS. It is presently unclear whether it is caused by an infectious and/or autoimmune/inflammatory process. Therefore, we suggest that aneurysms of large vessels should be systematically searched for in patients with WAS.


Subject(s)
Aortic Aneurysm/complications , Aortic Aneurysm/diagnosis , Wiskott-Aldrich Syndrome/complications , Wiskott-Aldrich Syndrome/diagnosis , Adolescent , Child , Follow-Up Studies , Humans , Young Adult
20.
Hum Mutat ; 31(12): 1269-79, 2010 Dec.
Article in English | MEDLINE | ID: mdl-20960466

ABSTRACT

Diamond-Blackfan Anemia (DBA) is characterized by a defect of erythroid progenitors and, clinically, by anemia and malformations. DBA exhibits an autosomal dominant pattern of inheritance with incomplete penetrance. Currently nine genes, all encoding ribosomal proteins (RP), have been found mutated in approximately 50% of patients. Experimental evidence supports the hypothesis that DBA is primarily the result of defective ribosome synthesis. By means of a large collaboration among six centers, we report here a mutation update that includes nine genes and 220 distinct mutations, 56 of which are new. The DBA Mutation Database now includes data from 355 patients. Of those where inheritance has been examined, 125 patients carry a de novo mutation and 72 an inherited mutation. Mutagenesis may be ascribed to slippage in 65.5% of indels, whereas CpG dinucleotides are involved in 23% of transitions. Using bioinformatic tools we show that gene conversion mechanism is not common in RP genes mutagenesis, notwithstanding the abundance of RP pseudogenes. Genotype-phenotype analysis reveals that malformations are more frequently associated with mutations in RPL5 and RPL11 than in the other genes. All currently reported DBA mutations together with their functional and clinical data are included in the DBA Mutation Database.


Subject(s)
Anemia, Diamond-Blackfan/genetics , Databases, Genetic , Mutation/genetics , Ribosomes/genetics , Anemia, Diamond-Blackfan/diagnosis , Base Sequence , Genetic Association Studies , Humans , Molecular Sequence Data , Mutagenesis/genetics , Ribosomal Proteins/genetics
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