Research

[Serratia infections, should we think about primary immunodeficiencies?]

Arch Argent Pediatr. 2017 Apr 01;115(2):e108-e111

Authors: Montaner Ramón A, Murillo Sanjuán L, Martínez Faci C, Guerrero Laleona C, Rodríguez-Vigil Iturrate C

Abstract
Chronic granulomatous disease (CGD) is a primary immunodeficiency with an incidence of 1/200,000-250,000 live births. CGD affects mainly male patients, most of the mutations being X-linked, and autosomal recessive forms occur more frequently in communities with greater numbers of consanguineous marriages. CGD is characterized by sensitivity to recurrent and severe bacterial and fungal infections, with formation of granulomas due to the inability of phagocytes to generate reactive oxygen compounds, necessary for the intracellular death of phagocytic microorganisms. We report three cases of CGD in which Serratia marcescens was isolated, and after detailed anamnesis and performance of neutrophil function tests, a molecular diagnosis of the disease was reached. CGD can be manifested in a wide variety of ways, so that high suspicion and a meticulous anamnesis are essential to reach a diagnosis.

PMID: 28318195 [PubMed – in process]

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Good Laboratory Practice Preclinical Safety Studies for GSK2696273 (MLV Vector-Based Ex Vivo Gene Therapy for Adenosine Deaminase Deficiency Severe Combined Immunodeficiency) in NSG Mice.

Hum Gene Ther Clin Dev. 2017 Mar;28(1):17-27

Authors: Carriglio N, Klapwijk J, Hernandez RJ, Vezzoli M, Chanut F, Lowe R, Elena D, Nord M, Albertini P, Cristofori P, Richards J, Staton H, Appleby J, Aiuti A, Sauer AV

Abstract
GSK2696273 (autologous CD34+ cells transduced with retroviral vector that encodes for the human adenosine deaminase [ADA] enzyme) is a gamma-retroviral ex vivo gene therapy of bone marrow-derived CD34+ cells for the treatment of adenosine deaminase deficiency severe combined immunodeficiency (ADA-SCID). ADA-SCID is a severe monogenic disease characterized by immunologic and nonimmunologic symptoms. Bone-marrow transplant from a matched related donor is the treatment of choice, but it is available for only a small proportion of patients. Ex vivo gene therapy of patient bone-marrow CD34+ cells is an alternative treatment. In order to prepare for a marketing authorization application in the European Union, preclinical safety studies in mice were requested by the European Medicines Agency (EMA). A pilot study and a main biodistribution study were performed according to Good Laboratory Practice (GLP) at the San Raffaele Telethon Institute for Gene Therapy test facility. In the main study, human umbilical cord blood (UCB)-derived CD34+ cells were transduced with gamma-retroviral vector used in the production of GSK2696273. Groups of 10 male and 10 female NOD-SCID gamma (NSG) mice were injected intravenously with a single dose of transduced- or mock-transduced UCB CD34+ cells, and they were observed for 4 months. Engraftment and multilineage differentiation of blood cells was observed in the majority of animals in both groups. There was no significant difference in the level of chimerism between the two groups. In the gene therapy group, vector was detectable in lymphohemopoietic and nonlymphohemopoietic tissues, consistent with the presence of gene-modified human hematopoietic donor cells. Given the absence of relevant safety concerns in the data, the nonclinical studies and the clinical experience with GSK2696273 supported a successful application for market authorization in the European Union for the treatment of ADA-SCID patients, for whom no suitable human leukocyte antigen-matched related donor is available.

PMID: 28319446 [PubMed – in process]

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Evaluation of the Safety, Tolerability, and Pharmacokinetics of Gammaplex(®) 10% Versus Gammaplex(®) 5% in Subjects with Primary Immunodeficiency.

J Clin Immunol. 2017 Mar 18;:

Authors: Wasserman RL, Melamed IR, Stein MR, Jolles S, Norton M, Moy JN, GMX07 Study Group

Abstract
PURPOSE: This phase 3, multicenter, open-label, randomized, two-period, crossover bioequivalence trial evaluated the safety, tolerability, and pharmacokinetics of intravenous immunoglobulins (IVIGs) Gammaplex 5% and Gammaplex 10% in 33 adults and 15 children with primary immunodeficiency diseases (PIDs).
METHODS: Eligible adults received five Gammaplex 5% infusions followed by five Gammaplex 10% infusions, or vice versa, stratified by a 21- or 28-day dosing regimen. Pediatric subjects received five Gammaplex 10% infusions only.
RESULTS: The primary objective, to demonstrate the bioequivalence of Gammaplex 10% and Gammaplex 5% at the 28-day dosing interval, was met based on the Gammaplex 10%/Gammaplex 5% ratio of area under the concentration versus time curve (AUC0-28) values. Throughout the study, total immunoglobulin G trough levels were well maintained, with total values generally ≥600 mg/dL (minimum level for study inclusion). At the dosing schedules and infusion rates used in this study, safety and tolerability were comparable and acceptable in adult and pediatric PID subjects treated with Gammaplex 10% and 5%.
CONCLUSIONS: In this study, the first direct comparison of 5% IVIG and 10% IVIG products in PID subjects, the pharmacokinetic analysis demonstrated bioequivalence of Gammaplex 10% and Gammaplex 5% at the 28-day dosing interval. The Gammaplex 10% formulation was safe and well tolerated in pediatric and adult PID subjects. Based on the results from this bridging study in PID subjects, Gammaplex 10% could be expected to have a therapeutic effect similar to the licensed Gammaplex 5%, which has demonstrated efficacy and tolerability in patients with PID and idiopathic thrombocytopenic purpura.

PMID: 28316003 [PubMed – as supplied by publisher]

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Mutations in PIK3R1 can lead to APDS2, SHORT syndrome or a combination of the two.

Clin Immunol. 2017 Mar 13;:

Authors: Bravo García-Morato M, García-Miñaúr S, Molina Garicano J, Santos Simarro F, López-Grandos E, Ferreira Cerdán A, Rodríguez Pena R

Abstract
Mutations in PIK3R1 gene have been associated to two different conditions: a primary immunodeficiency, called APDS2, of recent description and SHORT syndrome. 47 patients with APDS2 have been reported to date, only one of them sharing both PIK3R1-related phenotypes. Here we describe two more patients affected by APDS2 and SHORT syndrome, which highlights that this association may not be so infrequent. We recommend that patients with mutations in PIK3R1 gene should be assessed by both clinical immunologists and clinical geneticists.

PMID: 28302518 [PubMed – as supplied by publisher]

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X-linked agammaglobulinemia – first case with Bruton tyrosine kinase mutation from Pakistan.

J Pak Med Assoc. 2017 Mar;67(3):471-473

Authors: Zaidi SK, Qureshi S, Qamar FN

Abstract
X-linked agammaglobulinemia (XLA) is a primary immunodeficiency with more than 600 mutations in Bruton tyrosine kinase (Bkt) gene which are responsible for early-onset agammaglobulinemia and repeated infections. Herein we present a case of a 3-year-old boy with history of repeated diarrhoea and an episode of meningoencephalitis with hemiplegia. The workup showed extremely low levels of immunoglobulin with low CD+19 cells. Genetic analysis showed Btk mutation 18 c.1883delCp.T628fs. To the best of our knowledge this is the first report of a case of XLA confirmed by molecular technique from Pakistan.

PMID: 28304004 [PubMed – in process]

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Transcriptome analysis of bronchoalveolar lavage fluid from children with severe Mycoplasma pneumoniae pneumonia reveals novel gene expression and immunodeficiency.

Hum Genomics. 2017 Mar 16;11(1):4

Authors: Wang K, Gao M, Yang M, Meng F, Li D, Lu R, Wang Y, Zhuang H, Li M, Cheng G, Wang X

Abstract
BACKGROUND: A growing number of severe Mycoplasma pneumoniae pneumonia (MPP) cases have been reported recently. However, the pathogenesis of severe MPP is not clear. In the current study, transcriptome sequencing was used to identify gene expression and alternative splicing profiles to provide insights into the pathogenesis of severe MPP.
METHODS: RNAs of bronchoalveolar lavage fluid (BALF) samples from three severe MPP children and three mild MPP children were analyzed respectively by deep sequencing followed by computational annotation and quantification.
RESULTS: The gene expression analysis revealed 14 up-regulated and 34 down-regulated genes in severe MPP children comparing to mild MPP children. The top 10 most up-regulated genes were IGHV1-69, CH17-472G23.1, ATP1B2, FCER2, MUC21, IL13, FCRLB, CLEC5A, FAM124A, and INHBA. The top 10 most down-regulated genes were OSTN-AS1, IL22RA2, COL3A1, C1orf141, IGKV2-29, RP11-731F5.2, IGHV4-4, KIRREL, DNASE1L3, and COL6A2. Clustering analysis revealed similar expression pattern of CLEC5A, IL13, FCER2, and FLT1. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses revealed changes related to primary immunodeficiency in severe MPP children comparing to mild MPP children; the pathway involves CD19, TNFRSF13C, CD79A, and AICDA genes. Among the differentially expressed genes, significant alternative splicing events were found in FCER2 and FCRLA.
CONCLUSIONS: The current study on RNA sequencing provides novel insights into the pathogenesis of severe MPP in terms of gene expression and alternative splicing. The up-regulation of IL13, FCER2, FLT1, and CLEC5A and the down-regulation of CD79A, AICDA, CD19, and TNFRSF13C may contribute to the pathogenesis of severe MPP. The differential expressions of FCER2 and FCRLA could be due to their alternative splicing.

PMID: 28302172 [PubMed – in process]

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Incidence of typically Severe Primary Immunodeficiency Diseases in Consanguineous and Non-consanguineous Populations.

J Clin Immunol. 2017 Mar 16;:

Authors: Broides A, Nahum A, Mandola AB, Rozner L, Pinsk V, Ling G, Yerushalmi B, Levy J, Givon-Lavi N

Abstract
PURPOSE: Primary immunodeficiency diseases are considered to be rare diseases; however, data on the exact birth incidences of these diseases are sparse. Southern Israel is inhabited by two major populations: a relatively non-consanguineous Jewish population and a highly consanguineous Muslim Bedouin population. We sought to calculate the incidences of typically severe primary immunodeficiency diseases and compare the incidences in these populations.
METHODS: A retrospective analysis of all typically severe primary immunodeficiency diseases evaluated at a single center from January 1, 1996 to December 31, 2016. The amount of live births by population was the denominator for calculating the incidences by population.
RESULTS: A total of 95 patients were included, 85 of Bedouin and 10 of Jewish ethnicities. There were 152,331 births in the Bedouin and 160,998 births in the Jewish populations. The total incidence of typically severe primary immunodeficiency diseases was higher in the Bedouin population than expected based on previous studies. The total incidences were 55.8/10(5) births in the Bedouin population compared with 6.2/10(5) births in the Jewish population (P < 0.001). The incidences of all combined immunodeficiency diseases, ataxia telangiectasia, and infantile IBD due to interleukin 10 receptor defects were all significantly higher in the Bedouin population (P < 0.001). The incidence of X-linked agammaglobulinemia was not significantly different between both populations (P = 0.11).
CONCLUSIONS: Typically, severe primary immunodeficiency diseases are not rare diseases in a consanguineous population; these diseases are significantly more common in the Bedouin population. This finding is probably also applicable to other consanguineous populations, and in these populations, primary immunodeficiency diseases should not be regarded as rare diseases.

PMID: 28299599 [PubMed – as supplied by publisher]

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Exome sequencing identifies a novel TTC37 mutation in the first reported case of Trichohepatoenteric syndrome (THE-S) in South Africa.

BMC Med Genet. 2017 Mar 14;18(1):26

Authors: Kinnear C, Glanzmann B, Banda E, Schlechter N, Durrheim G, Neethling A, Nel E, Schoeman M, Johnson G, van Helden PD, Hoal EG, Esser M, Urban M, Möller M

Abstract
BACKGROUND: Trichohepatoenteric syndrome (THE-S) or phenotypic diarrhoea of infancy is a rare autosomal recessive disorder characterised by severe infantile diarrhoea, facial dysmorphism, immunodeficiency and woolly hair. It was first described in 1982 in two infants with intractable diarrhoea, liver cirrhosis and abnormal hair structure on microscopy. We report on two siblings from a consanguineous family of Somali descent who, despite extensive clinical investigation, remained undiagnosed until their demise. The index patient died of fulminant cytomegalovirus pneumonitis at 3 months of age.
METHODS: Whole exome sequencing (WES) was performed on a premortem DNA sample from the index case. Variants in a homozygous recessive state or compound heterozygous state were prioritized as potential candidate variants using TAPER™. Sanger sequencing was done to genotype the parents, unaffected sibling and a deceased sibling for the variant of interest.
RESULTS: Exome sequencing identified a novel homozygous mutation (c.4507C > T, rs200067423) in TTC37 which was confirmed by Sanger sequencing in the index case. The identification of this mutation led to the diagnosis of THE-S in the proband and the same homozygous variant was confirmed in a male sibling who died 4 years earlier with severe chronic diarrhoea of infancy. The unaffected parents and sister were heterozygous for the identified variant.
CONCLUSIONS: WES permitted definitive genetic diagnosis despite an atypical presentation in the index case and suggests that severe infection, likely secondary to immunodeficiency, may be a presenting feature. In addition definitive molecular diagnosis allows for genetic counseling and future prenatal diagnosis, and demonstrates the value of WES for post-mortem diagnosis of disorders with a non-specific clinical presentation in which a Mendelian cause is suspected.

PMID: 28292286 [PubMed – in process]

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DOCK 8 Deficiency, EBV+ Lymphomatoid Granulomatosis, and Intrafamilial Variation in Presentation.

Front Pediatr. 2017;5:38

Authors: Dimitriades VR, Devlin V, Pittaluga S, Su HC, Holland SM, Wilson W, Dunleavy K, Shah NN, Freeman AF

Abstract
Dedicator of cytokinesis 8 (DOCK8) deficiency is an autosomal recessive, combined immunodeficiency within the spectrum of hyper-IgE syndromes. Epstein-Barr virus-positive lymphomatoid granulomatosis (LYG) (EBV + LYG) is a rare diagnosis and a previously unreported presentation of DOCK8 deficiency. A 10-year-old girl was initially evaluated for mild eczema and recurrent sinopulmonary infections. She had normal immunoglobulins with elevated IgE, poor polysaccharide response with low switched memory B cells, low CD4 count, and normal mitogen and antigen responses. Despite clinical improvement following immunoglobulin replacement, a prolonged cough prompted a CT scan, which showed nodules. Biopsy identified a Grade 2 EBV + LYG. Due to an inadequate response with chemotherapy, further workup for primary immunodeficiency was performed. With her symptoms of eczema and IgE elevation, along with her brother’s history of recurrent sinopulmonary infections and warts, targeted sequencing of DOCK8 was performed revealing compound heterozygous mutations for the two siblings. Both patients were successfully transplanted with resolution of the LYG and warts, respectively. This is the first reported case of LYG in DOCK8 deficiency. The EBV-driven lymphoproliferative disease along with the infection history in the brother led to the diagnosis of DOCK8 deficiency and curative hematopoietic stem cell transplants.

PMID: 28293550 [PubMed – in process]

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Follicular T Cells from smB(-) Common Variable Immunodeficiency Patients Are Skewed Toward a Th1 Phenotype.

Front Immunol. 2017;8:174

Authors: Cunill V, Clemente A, Lanio N, Barceló C, Andreu V, Pons J, Ferrer JM

Abstract
Germinal center follicular T helper (GCTfh) cells are essential players in the differentiation of B cells. Circulating follicular T helper (cTfh) cells share phenotypic and functional properties with GCTfh cells. Distinct subpopulations of cTfh with different helper capabilities toward B cells can be identified: cTfh1 (CXCR3(+)CCR6(-)), cTfh2 (CXCR3(-)CCR6(-)), and cTfh17 (CXCR3(-)CCR6(+)). Alterations in cTfh function and/or distribution have been associated with autoimmunity, infectious diseases, and more recently, with several monogenic immunodeficiencies. Common variable immunodeficiency (CVID) disease is the commonest symptomatic primary immunodeficiency with a genetic cause identified in only 2-10% of patients. Although a heterogeneous disease, most patients show a characteristic defective B cell differentiation into memory B cells or antibody-secreting cells. We investigated if alterations in CVID cTfh cells frequency or distribution into cTfh1, cTfh2, and cTfh17 subpopulations and regulatory follicular T (Tfr) cells could be related to defects in CVID B cells. We found increased percentages of cTfh exhibiting higher programmed death-1 expression and altered subpopulations distribution in smB(-) CVID patients. In contrast to smB(+) patients and controls, cTfh from smB(-) CVID patients show increased cTfh1 and decreased cTfh17 subpopulation percentages and increased CXCR3(+)CCR6(+) cTfh, a population analogous to the recently described pathogenic Th17.1. Moreover, Tfr cells are remarkably decreased only in smB(-) CVID patients. In conclusion, increased cTfh17.1 and cTfh1/cTfh17 ratio in CVID patients could influence B cell fate in smB(-) CVID patients, with a more compromised B cell compartment, and the decrease in Tfr cells may lead to high risk of autoimmune conditions in CVID patients.

PMID: 28289412 [PubMed – in process]

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