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A nonsense mutation in IKBKB causes combined immunodeficiency.

Blood. 2014 Aug 18;

Authors: Mousallem T, Yang J, Urban T, Wang H, Adeli M, Parrott RE, Roberts JL, Goldstein D, Buckley RH, Zhong XP

Abstract
Identification of the molecular etiologies of primary immunodeficiencies has led to important insights into the development and function of the immune system. We report here the cause of Combined Immunodeficiency in 4 patients from 2 different consanguineous Qatari families with similar clinical and immunologic phenotypes. The patients presented at an early age with fungal, viral and bacterial infections and hypogammaglobulinemia. Although their B- and T-cell numbers were normal, they had low regulatory T-cell and NK-cell numbers. Moreover, patients’ T-cells were mostly CD45RA(+) naíve cells and defective in activation following TCR stimulation. All patients contained the same homozygous nonsense mutation in IKBKB (R286X) revealed by whole-exome sequencing with undetectable IKKβ and severely decreased NEMO proteins. Mutant IKKβ(R286X) was unable to complex with IKKα/NEMO. Immortalized patient B-cells displayed impaired IκBα phosphorylation and NFκB nuclear translocation. These data indicate that mutated IKBKB is the likely cause of immunodeficiency in these four patients.

PMID: 25139357 [PubMed – as supplied by publisher]

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Clinical features of Candidiasis in patients with inherited interleukin 12 receptor β1 deficiency.

Clin Infect Dis. 2014 Jan;58(2):204-13

Authors: Ouederni M, Sanal O, Ikinciogullari A, Tezcan I, Dogu F, Sologuren I, Pedraza-Sánchez S, Keser M, Tanir G, Nieuwhof C, Colino E, Kumararatne D, Levy J, Kutukculer N, Aytekin C, Herrera-Ramos E, Bhatti M, Karaca N, Barbouche R, Broides A, Goudouris E, Franco JL, Parvaneh N, Reisli I, Strickler A, Shcherbina A, Somer A, Segal A, Angel-Moreno A, Lezana-Fernandez JL, Bejaoui M, Bobadilla-Del Valle M, Kachboura S, Sentongo T, Ben-Mustapha I, Bustamante J, Picard C, Puel A, Boisson-Dupuis S, Abel L, Casanova JL, Rodríguez-Gallego C

Abstract
BACKGROUND: Interleukin 12Rβ1 (IL-12Rβ1)-deficient patients are prone to clinical disease caused by mycobacteria, Salmonella, and other intramacrophagic pathogens, probably because of impaired interleukin 12-dependent interferon γ production. About 25% of patients also display mucocutaneous candidiasis, probably owing to impaired interleukin 23-dependent interleukin 17 immunity. The clinical features and outcome of candidiasis in these patients have not been described before, to our knowledge. We report here the clinical signs of candidiasis in 35 patients with IL-12Rβ1 deficiency.
RESULTS: Most (n = 71) of the 76 episodes of candidiasis were mucocutaneous. Isolated oropharyngeal candidiasis (OPC) was the most common presentation (59 episodes, 34 patients) and was recurrent or persistent in 26 patients. Esophageal candidiasis (n = 7) was associated with proven OPC in 2 episodes, and cutaneous candidiasis (n = 2) with OPC in 1 patient, whereas isolated vulvovaginal candidiasis (VVC; n = 3) was not. Five episodes of proven invasive candidiasis were documented in 4 patients; 1 of these episodes was community acquired in the absence of any other comorbid condition. The first episode of candidiasis occurred earlier in life (median age±standard deviation, 1.5 ± 7.87 years) than infections with environmental mycobacteria (4.29 ± 11.9 years), Mycobacterium tuberculosis (4 ± 3.12 years), or Salmonella species (4.58 ± 4.17 years) or other rare infections (3 ± 11.67 years). Candidiasis was the first documented infection in 19 of the 35 patients, despite the vaccination of 10 of these 19 patients with live bacille Calmette-Guérin.
CONCLUSIONS: Patients who are deficient in IL-12Rβ1 may have candidiasis, usually mucocutaneous, which is frequently recurrent or persistent. Candidiasis may be the first clinical manifestation in these patients.

PMID: 24186907 [PubMed – indexed for MEDLINE]

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Mycobacterium simiae Infection in Two Unrelated Patients with Different Forms of Inherited IFN-γR2 Deficiency.

J Clin Immunol. 2014 Aug 19;

Authors: Martínez-Barricarte R, Megged O, Stepensky P, Casimir P, Moncada-Velez M, Averbuch D, Assous MV, Abuzaitoun O, Kong XF, Pedergnana V, Deswarte C, Migaud M, Rose-John S, Itan Y, Boisson B, Belkadi A, Conti F, Abel L, Vogt G, Boisson-Dupuis S, Casanova JL, Bustamante J

Abstract
Interferon-γ receptor 2 (IFN-γR2) deficiency is a rare primary immunodeficiency characterized by predisposition to infections with weakly virulent mycobacteria, such as environmental mycobacteria and BCG vaccines. We describe here two children with IFN-γR2 deficiency, from unrelated, consanguineous kindreds of Arab and Israeli descent. The first patient was a boy who died at the age of 4.5 years, from recurrent, disseminated disease caused by Mycobacterium simiae. His IFN-γR2 defect was autosomal recessive and complete. The second patient was a girl with multiple disseminated mycobacterial infections, including infection with M. simiae. She died at the age of 5 years, a short time after the transplantation of umbilical cord blood cells from an unrelated donor. Her IFN-γR2 defect was autosomal recessive and partial. Autosomal recessive IFN-γR2 deficiency is life-threatening, even in its partial form, and genetic diagnosis and familial counseling are therefore particularly important for this condition. These two cases are the first of IFN-γR2 deficiency associated with M. simiae infection to be described.

PMID: 25135595 [PubMed – as supplied by publisher]

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Complex regional pain syndrome treated with intravenous immunoglobulin in a patient with common variable immune deficiency.

Pain Ther. 2013 Dec;2(2):129-34

Authors: Tachdjian R

Abstract
INTRODUCTION: Common variable immunodeficiency (CVID) represents a large heterogeneous group of antibody-deficiency syndromes associated with a wide range of clinical features and a lack of defined causes in the realm of primary immunodeficiencies. Here, we present a case of CVID in a 62-year-old white male patient with a history of longstanding complex regional pain syndrome (CRPS).
CASE PRESENTATION: His medical history included multiple sinus infections per year and several pneumonias requiring antibiotics. He has had various back surgeries, including a laminectomy at the L4 level 1 year prior to his diagnosis. Thereafter, he underwent four sympathetic nerve blocks with minimal pain relief. Blood chemistries showed a normal white blood cell count with a normal differential, but increased erythrocyte sedimentation rate and C-reactive protein levels. Total Ig (Immunoglobulin)G was 611 mg/dL (normal 700-1,600), IgG1 was 425 mg/dL (341-894), IgG2 was 114 mg/dL (171-632), IgG3 was 14.4 mg/dL (18.4-106), and IgG4 was 7.4 mg/dL (2.4-121). IgA was 47 mg/dL (normal 70-400), IgM was 131 mg/dL (40-230), and IgE was 4.5 kU/L (<4.0). He only had 10 of 23 pneumococcal titers in the protective range post-vaccination. Upon treatment of the CVID with intravenous immunoglobulin, the patient’s pain levels were significantly decreased and have been maintained for more than 2 years.
CONCLUSION: Therefore, immunoglobulin therapy appears to have been beneficial in the treatment of the patient’s symptoms of CRPS, including pain. Additional studies investigating the mechanism by which immunoglobulin therapy may reduce the inflammation and pain of CRPS are needed.

PMID: 25135151 [PubMed]

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Hypomorphic homozygous mutations in phosphoglucomutase 3 (PGM3) impair immunity and increase serum IgE levels.

J Allergy Clin Immunol. 2014 May;133(5):1410-9, 1419.e1-13

Authors: Sassi A, Lazaroski S, Wu G, Haslam SM, Fliegauf M, Mellouli F, Patiroglu T, Unal E, Ozdemir MA, Jouhadi Z, Khadir K, Ben-Khemis L, Ben-Ali M, Ben-Mustapha I, Borchani L, Pfeifer D, Jakob T, Khemiri M, Asplund AC, Gustafsson MO, Lundin KE, Falk-Sörqvist E, Moens LN, Gungor HE, Engelhardt KR, Dziadzio M, Stauss H, Fleckenstein B, Meier R, Prayitno K, Maul-Pavicic A, Schaffer S, Rakhmanov M, Henneke P, Kraus H, Eibel H, Kölsch U, Nadifi S, Nilsson M, Bejaoui M, Schäffer AA, Smith CI, Dell A, Barbouche MR, Grimbacher B

Abstract
BACKGROUND: Recurrent bacterial and fungal infections, eczema, and increased serum IgE levels characterize patients with the hyper-IgE syndrome (HIES). Known genetic causes for HIES are mutations in signal transducer and activator of transcription 3 (STAT3) and dedicator of cytokinesis 8 (DOCK8), which are involved in signal transduction pathways. However, glycosylation defects have not been described in patients with HIES. One crucial enzyme in the glycosylation pathway is phosphoglucomutase 3 (PGM3), which catalyzes a key step in the synthesis of uridine diphosphate N-acetylglucosamine, which is required for the biosynthesis of N-glycans.
OBJECTIVE: We sought to elucidate the genetic cause in patients with HIES who do not carry mutations in STAT3 or DOCK8.
METHODS: After establishing a linkage interval by means of SNPchip genotyping and homozygosity mapping in 2 families with HIES from Tunisia, mutational analysis was performed with selector-based, high-throughput sequencing. Protein expression was analyzed by means of Western blotting, and glycosylation was profiled by using mass spectrometry.
RESULTS: Mutational analysis of candidate genes in an 11.9-Mb linkage region on chromosome 6 shared by 2 multiplex families identified 2 homozygous mutations in PGM3 that segregated with disease status and followed recessive inheritance. The mutations predict amino acid changes in PGM3 (p.Glu340del and p.Leu83Ser). A third homozygous mutation (p.Asp502Tyr) and the p.Leu83Ser variant were identified in 2 other affected families, respectively. These hypomorphic mutations have an effect on the biosynthetic reactions involving uridine diphosphate N-acetylglucosamine. Glycomic analysis revealed an aberrant glycosylation pattern in leukocytes demonstrated by a reduced level of tri-antennary and tetra-antennary N-glycans. T-cell proliferation and differentiation were impaired in patients. Most patients had developmental delay, and many had psychomotor retardation.
CONCLUSION: Impairment of PGM3 function leads to a novel primary (inborn) error of development and immunity because biallelic hypomorphic mutations are associated with impaired glycosylation and a hyper-IgE-like phenotype.

PMID: 24698316 [PubMed – indexed for MEDLINE]

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Genetic variation in schlafen genes in a patient with a recapitulation of the murine Elektra phenotype.

J Allergy Clin Immunol. 2014 May;133(5):1462-5, 1465.e1-5

Authors: Recher M, Karjalainen-Lindsberg ML, Lindlöf M, Söderlund-Venermo M, Lanzi G, Väisänen E, Kumar A, Sadeghi M, Berger CT, Alitalo T, Anttila P, Kolehmainen M, Franssila R, Chen T, Siitonen S, Delmonte OM, Walter JE, Pessach I, Hess C, Simpson MA, Navarini AA, Giliani S, Hedman K, Seppänen M, Notarangelo LD

PMID: 24373355 [PubMed – indexed for MEDLINE]

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Differential regulation of Bdnf expression in cortical neurons by class-selective histone deacetylase inhibitors.

Neuropharmacology. 2013 Dec;75:106-15

Authors: Koppel I, Timmusk T

Abstract
Histone deactylase (HDAC) inhibitors show promise as therapeutics for neurodegenerative and psychiatric diseases. Increased expression of brain-derived neurotrophic factor (BDNF) has been associated with memory-enhancing and neuroprotective properties of these drugs, but the mechanism of BDNF induction is not well understood. Here, we compared the effects of a class I/IIb selective HDAC inhibitor SAHA, a class I selective inhibitor MS-275, a class II selective inhibitor MC1568 and a HDAC6 selective inhibitor tubacin on Bdnf mRNA expression in rat primary neurons. We show that inhibition of class II HDACs resulted in rapid upregulation of Bdnf mRNA levels, whereas class I HDAC inhibition produced a markedly delayed Bdnf induction. In contrast to relatively slow upregulation of Bdnf transcripts, histone acetylation at BDNF promoters I and IV was rapidly induced by SAHA. Bdnf induction by SAHA and MS-275 at 24 h was sensitive to protein synthesis inhibition, suggesting that delayed Bdnf induction by HDAC inhibitors is secondary to changed expression of its regulators. HDAC4 and HDAC5 repressed Bdnf promoter IV activity, supporting the role of class II HDACs in regulation of Bdnf expression. In addition, we show a critical role for the cAMP/Ca2+ response element (CRE) in induction of Bdnf promoter IV by MS-275, MC1568, SAHA and sodium valproate. In contrast, MEF2-binding CaRE1 element was not necessary for promoter IV induction by HDAC inhibition. Finally, we show that similarly to Bdnf, the studied HDAC inhibitors differentially induced expression of neuronal activity-regulated genes c-fos and Arc. Together, our findings implicate class II HDACs in transcriptional regulation of Bdnf and indicate that class II selective HDAC inhibitors may have potential as therapeutics for nervous system disorders.

PMID: 23916482 [PubMed – indexed for MEDLINE]

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A human immunodeficiency caused by mutations in the PIK3R1 gene.

J Clin Invest. 2014 Aug 18;

Authors: Deau MC, Heurtier L, Frange P, Suarez F, Bole-Feysot C, Nitschke P, Cavazzana M, Picard C, Durandy A, Fischer A, Kracker S

Abstract
Recently, patient mutations that activate PI3K signaling have been linked to a primary antibody deficiency. Here, we used whole-exome sequencing and characterized the molecular defects in 4 patients from 3 unrelated families diagnosed with hypogammaglobulinemia and recurrent infections. We identified 2 different heterozygous splice site mutations that affect the same splice site in PIK3R1, which encodes the p85α subunit of PI3K. The resulting deletion of exon 10 produced a shortened p85α protein that lacks part of the PI3K p110-binding domain. The hypothetical loss of p85α-mediated inhibition of p110 activity was supported by elevated phosphorylation of the known downstream signaling kinase AKT in patient T cell blasts. Analysis of patient blood revealed that naive T and memory B cell counts were low, and T cell blasts displayed enhanced activation-induced cell death, which was corrected by addition of the PI3Kδ inhibitor IC87114. Furthermore, B lymphocytes proliferated weakly in response to activation via the B cell receptor and TLR9, indicating a B cell defect. The phenotype exhibited by patients carrying the PIK3R1 splice site mutation is similar to that of patients carrying gain-of-function mutations in PIK3CD. Our results suggest that PI3K activity is tightly regulated in T and B lymphocytes and that various defects in the PI3K-triggered pathway can cause primary immunodeficiencies.

PMID: 25133428 [PubMed – as supplied by publisher]

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Too much of a good thing: immunodeficiency due to hyperactive PI3K signaling.

J Clin Invest. 2014 Aug 18;:1-3

Authors: Walsh CM, Fruman DA

Abstract
Primary immune deficiency diseases arise due to heritable defects that often involve signaling molecules required for immune cell function. Typically, these genetic defects cause loss of gene function, resulting in primary immune deficiencies such as severe combined immune deficiency (SCID) and X-linked agammaglobulinemia (XLA); however, gain-of-function mutations may also promote immune deficiency. In this issue of the JCI, Deau et al. establish that gain-of-function mutations in PIK3R1, which encodes the p85α regulatory subunit of class IA PI3Ks, lead to immunodeficiency. These observations are consistent with previous reports that hyperactivating mutations in PIK3CD, which encodes the p110δ catalytic subunit, are capable of promoting immune deficiency. Mutations that reduce PI3K activity also result in defective lymphocyte development and function; therefore, these findings support the notion that too little or too much PI3K activity leads to immunodeficiency.

PMID: 25133419 [PubMed – as supplied by publisher]

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Lymphocytes subsets reference values in childhood.

Cytometry A. 2014 Aug 6;

Authors: Tosato F, Bucciol G, Pantano G, Putti MC, Sanzari MC, Basso G, Plebani M

Abstract
Immunophenotyping of blood lymphocyte subsets and activation markers is a basic tool in the diagnostic process of primary immunodeficiency diseases, its use becoming more and more widespread as the knowledge about these illnesses increases. However, the availability of reliable reference values, which need to be age-matched for the pediatric population, is a pre-requisite for the reliable interpretation of immunophenotyping data. Aim of this study is to analyze the lymphocyte subsets and activation markers distribution in children aged 0-18 years referring to the University Hospital of Padova and to create age-matched reference values expressed by percentiles, thus providing a valuable guideline for the interpretation of the immunophenotype. © 2014 International Society for Advancement of Cytometry.

PMID: 25132325 [PubMed – as supplied by publisher]

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