Research

X-linked hyper-IgM syndrome associated with pulmonary manifestations: A very rare case of functional mutation in CD40L gene in Iran.

Curr Res Transl Med. 2018 Mar 07;:

Authors: Torabizadeh M, Nabavi M, Zadkarami M, Shahrooei M

Abstract
Hyper IgM (HIGM) syndromes are a complex of primary immunodeficiency disorders. A 4-years-old boy with recurrent fever and chills, dyspnea, sort throat for a month was admitted to emergency department. In the current case, whole exome sequencing followed by Sanger sequencing were employed in order to screen probable functional mutations. Molecular analysis revealed a functional mutation across the CD40L gene (NM_000074: exon5: c.T464C) resulted in amino acid change p.L155P attributed to X-linked hyper IgM syndrome. The findings of the current study signify the critical role of microbial infection as well as XHIGM screening, particularly in those children cases with respiratory symptoms.

PMID: 29525420 [PubMed – as supplied by publisher]

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Non-PTLD Malignancy post HSCT in patients with Primary Immunodeficiency: UK experience.

J Allergy Clin Immunol. 2018 Mar 07;:

Authors: Unni MNM, Elfeky R, Rao K, Nademi Z, Chiesa R, Amrolia P, Skinner R, Slater O, Worth A, Flood T, Abinun M, Hambleton S, Qasim W, Gaspar HB, Cant AJ, Gennery AR, Veys P, Slatter MA

Abstract
Secondary malignancy post haematopoietic stem cell transplantation (HSCT) for malignant disorders is well recognized. There are very few published reports on malignancy post HSCT for Primary Immunodeficiency (PID). We report 12 cases of 944 patients, who developed non-PTLD malignancy post-HSCT for PID.

PMID: 29524534 [PubMed – as supplied by publisher]

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Delivery of Designer Epigenome Modifiers into Primary Human T Cells.

Methods Mol Biol. 2018;1767:189-203

Authors: Mlambo T, Romito M, Cornu TI, Mussolino C

Abstract
The development of tools which allow for the precise alterations of the epigenetic landscape in desired genomic locations presents exciting possibilities toward further understanding how gene expression is regulated and opportunities to harness these properties for therapeutic purposes. In contrast to gene knockout strategies, targeted epigenome modifications, such as editing of DNA methylation, can mediate gene expression modulation without changing the genomic sequence. Thereby, in a therapeutic context, this strategy may offer a safer route as compared to gene disruption using designer nucleases that, to reach high efficiencies, relies on the occurrence of random mutations to inactivate the target gene. In addition, therapeutic benefit is influenced not only by the intrinsic safety and efficacy of the tools used but also by methods that allow efficient and non-toxic transfer of the selected reagents in the target cells. Here, we describe a detailed protocol, for safe delivery of TALE-based designer epigenome modifiers in the form of in vitro transcribed mRNA into primary human CD4+ T cells to efficiently silence the expression of an exemplary human gene (i.e., CCR5).

PMID: 29524135 [PubMed – in process]

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[Current status and prospects of primary immunodeficiency management in China].

Zhonghua Er Ke Za Zhi. 2018 Mar 02;56(3):163-165

Authors: Yang J, Zhao XD

PMID: 29518824 [PubMed – in process]

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Normal development of mice lacking PAXX, the paralogue of XRCC4 and XLF.

FEBS Open Bio. 2018 Mar;8(3):426-434

Authors: Gago-Fuentes R, Xing M, Sæterstad S, Sarno A, Dewan A, Beck C, Bradamante S, Bjørås M, Oksenych V

Abstract
DNA repair consists of several cellular pathways which recognize and repair damaged DNA. The classical nonhomologous DNA end-joining (NHEJ) pathway repairs double-strand breaks in DNA. It is required for maturation of both B and T lymphocytes by supporting V(D)J recombination as well as B-cell differentiation during class switch recombination (CSR). Inactivation of NHEJ factors Ku70, Ku80, XRCC4, DNA ligase 4, DNA-PKcs, and Artemis impairs V(D)J recombination and blocks lymphocyte development. Paralogue of XRCC4 and XLF (PAXX) is an accessory NHEJ factor that has a significant impact on the repair of DNA lesions induced by ionizing radiation in human, murine, and chicken cells. However, the role of PAXX during development is poorly understood. To determine the physiological role of PAXX, we deleted part of the Paxx promoter and the first two exons in mice. Further, we compared Paxx-knockout mice with wild-type (WT) and NHEJ-deficient controls including Ku80- and Dna-pkcs-null and severe combined immunodeficiency mice. Surprisingly, Paxx-deficient mice were not distinguishable from the WT littermates; they were the same weight and size, fertility status, had normal spleen, thymus, and bone marrow. Paxx-deficient mice had the same number of chromosomal and chromatid breaks as WT mice. Moreover, Paxx-deficient primary B lymphocytes had the same level of CSR as lymphocytes isolated from WT mice. We concluded that PAXX is dispensable for normal mouse development.

PMID: 29511619 [PubMed]

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[Primary antibody deficiency syndromes].

Ugeskr Laeger. 2018 Feb 26;180(9):

Authors: Larsen CS, Katzenstein TL

Abstract
Primary antibody deficiency syndromes (PAD) are a group of primary immunodeficiencies (PID) characterized by reduced production of immunoglobulins and recurrent respiratory tract infections. PAD varies from rare but life-threatening agammaglobulinaemias to frequent but often asymptomatic conditions such as selective immunoglobulin(Ig)A deficiency or IgG subclass deficiency. Common variable immunodeficiency is the clinically most important PAD. Hypogammaglobulinaemia may be associated with other PID or may be drug-induced or caused by infectious diseases, haematological malignancies or protein loss.

PMID: 29506644 [PubMed – in process]

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Dried Blood Spots, an Affordable Tool to Collect, Ship, and Sequence gDNA from Patients with an X-Linked Agammaglobulinemia Phenotype Residing in a Developing Country.

Front Immunol. 2018;9:289

Authors: Segundo GRS, Nguyen ATV, Thuc HT, Nguyen LNQ, Kobayashi RH, Le HT, Le HTM, Torgerson TR, Ochs HD

Abstract
Background: New sequencing techniques have revolutionized the identification of the molecular basis of primary immunodeficiency disorders (PID) not only by establishing a gene-based diagnosis but also by facilitating defect-specific treatment strategies, improving quality of life and survival, and allowing factual genetic counseling. Because these techniques are generally not available for physicians and their patients residing in developing countries, collaboration with overseas laboratories has been explored as a possible, albeit cumbersome, strategy. To reduce the cost of time and temperature-sensitive shipping, we selected Guthrie cards, developed for newborn screening, to collect dried blood spots (DBS), as a source of DNA that can be shipped by regular mail at minimal cost.
Method: Blood was collected and blotted onto the filter paper of Guthrie cards by completely filling three circles. We enrolled 20 male patients with presumptive X-linked agammaglobulinemia (XLA) cared for at the Vietnam National Children’s Hospital, their mothers, and several sisters for carrier analysis. DBS were stored at room temperature until ready to be shipped together, using an appropriately sized envelope, to a CLIA-certified laboratory in the US for sequencing. The protocol for Sanger sequencing was modified to account for the reduced quantity of gDNA extracted from DBS.
Result: High-quality gDNA could be extracted from every specimen. Bruton tyrosine kinase (BTK) mutations were identified in 17 of 20 patients studied, confirming the diagnosis of XLA in 85% of the study cohort. Type and location of the mutations were similar to those reported in previous reviews. The mean age when XLA was suspected clinically was 4.6 years, similar to that reported by Western countries. Two of 15 mothers, each with an affected boy, had a normal BTK sequence, suggesting gonadal mosaicism.
Conclusion: DBS collected on Guthrie cards can be shipped inexpensively by airmail across continents, providing sufficient high-quality gDNA for Sanger sequencing overseas. By using this method of collecting gDNA, we were able to confirm the diagnosis of XLA in 17 of 20 Vietnamese patients with the clinical diagnosis of agammaglobulinemia.

PMID: 29503650 [PubMed]

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Laboratory evaluation of the IFN-γ circuit for the molecular diagnosis of Mendelian susceptibility to mycobacterial disease.

Crit Rev Clin Lab Sci. 2018 Mar 04;:1-21

Authors: Esteve-Solé A, Sologuren I, Martínez-Saavedra MT, Deyà-Martínez À, Oleaga-Quintas C, Martinez-Barricarte R, Martin-Nalda A, Juan M, Casanova JL, Rodriguez-Gallego C, Alsina L, Bustamante J

Abstract
The integrity of the interferon (IFN)-γ circuit is necessary to mount an effective immune response to intra-macrophagic pathogens, especially Mycobacteria. Inherited monogenic defects in this circuit that disrupt the production of, or response to, IFN-γ underlie a primary immunodeficiency known as Mendelian susceptibility to mycobacterial disease (MSMD). Otherwise healthy patients display a selective susceptibility to clinical disease caused by poorly virulent mycobacteria such as BCG (bacille Calmette-Guérin) vaccines and environmental mycobacteria, and more rarely by other intra-macrophagic pathogens, particularly Salmonella and M. tuberculosis. There is high genetic and allelic heterogeneity, with 19 genetic etiologies due to mutations in 10 genes that account for only about half of the patients reported. An efficient laboratory diagnostic approach to suspected MSMD patients is important, because it enables the establishment of specific therapeutic measures that will improve the patient’s prognosis and quality of life. Moreover, it is essential to offer genetic counseling to affected families. Herein, we review the various genetic and immunological diagnostic approaches that can be used in concert to reach a molecular and cellular diagnosis in patients with MSMD.

PMID: 29502462 [PubMed – as supplied by publisher]

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Analysis of Genes Associated with Monogenic Primary Immunodeficiency Identifies Rare Variants in XIAP in Patients With Crohn’s disease.

Gastroenterology. 2018 Feb 28;:

Authors: Amininejad L, Charloteaux B, Theatre E, Liefferinckx C, Dmitrieva J, Hayard P, Muls V, Maisin JM, Schapira M, Ghislain JM, Closset P, Talib M, Abramowicz M, Momozawa Y, Deffontaine V, Crins F, Mni M, Karim L, Cambisano N, Ornemese S, Zucchi A, Minsart C, Deviere J, Hugot JP, De Vos M, Louis E, Vermeire S, Van Gossum A, Coppieters W, Twizere JC, Georges M, Franchimont D, International IBD Genetics Consortium (IIBDGC)

Abstract
BACKGROUND & AIMS: A few rare monogenic primary immunodeficiencies (PID) are characterized by chronic intestinal inflammation that resembles Crohn’s disease (CD). We investigated whether 23 genes associated with 10 of these monogenic disorders contain common, low-frequency or rare variants that increase risk for CD.
METHODS: Common and low frequency variants in 1 Mb loci centered on the candidate genes were analyzed using meta-data corresponding to genotypes of approximately 17,000 patients with CD or without CD (controls) in Europe. The contribution of rare variants was assessed by high-throughput sequencing of 4750 individuals, including 660 early-onset and/or familial cases among the 2390 patients with CD. Variants were expressed from vectors in SW480 or HeLa cells and functions of their products were analyzed in immunofluorescence, luciferase, immunoprecipitation, and immunoblot assays.
RESULTS: We reproduced the association of the IL10 locus with CD (P=.007), although none of the significantly associated variants modified the coding sequence of IL10. We found XIAP to be significantly enriched for rare coding mutations in patients with CD vs controls (P=.02). We identified 4 previously unreported missense variants associated with CD. Variants in XIAP cause PID X-linked lymphoproliferative disease type 2 (XLP2), yet none of the carriers of these variants had all the clinical features of XLP2. Identified XIAP variants S123N, R233Q and P257A were associated with an impaired activation of NOD2 signaling following MDP stimulation.
CONCLUSIONS: In a systematic analysis of variants in 23 PID-associated genes, we confirmed the association of variants in XIAP with CD. Further screens for CD-associated variants and analyses of their functions could increase our understanding of the relationship between PID-associated genes and CD pathogenesis.

PMID: 29501442 [PubMed – as supplied by publisher]

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