Manish Butte

R-loops cause genomic instability in Wiskott-Aldrich syndrome Thelper lymphocytes.

J Allergy Clin Immunol. 2017 Dec 14;:

Authors: Sarkar K, Han SS, Wen KK, Ochs HD, Dupré L, Seidman MM, Vyas YM

Abstract
BACKGROUND: Wiskott-Aldrich syndrome (WAS), X-linked thrombocytopenia (XLT), and X-linked neutropenia (XLN), caused by WAS mutations affecting WASp expression or activity, manifest in immunodeficiency, autoimmunity, genomic-instability, and lymphoid-cancer. WASp supports filamentous-actin formation in the cytoplasm and gene-transcription in the nucleus. Although the genetic basis for XLT/WAS has been clarified, the relationships between mutant forms of WASp and the diverse features of these disorders remain ill-defined.
OBJECTIVE: To define how dysfunctional gene transcription is causally linked to the degree of Thelper (Th) cell deficiency and genomic instability in XLT/WAS clinical spectrum.
METHODS: In human Th1- or Th2-skewing cell culture systems, co-transcriptional R-loops (RNA:DNA duplex and displaced single-stranded DNA) and DNA double-strand breaks (DSBs) were monitored in multiple XLT and WAS patient samples, and in normal T cells depleted of WASp.
RESULTS: WASp-deficiency provokes increased R-loops and R-loop-mediated DSBs in Th1-cells relative to Th2-cells. Mechanistically, chromatin-occupancy of Serine2-unphosphorylated-RNA Polymerase II is increased and that of topoisomerase-1, a R-loop preventing factor, is decreased at R-loop-enriched regions of IFNG and TBX21 (Th1 genes) in Th1-cells. These aberrations accompany increased unspliced (intron-retained) and decreased spliced mRNA of IFNG and TBX21 but not of IL13 (Th2-gene). Significantly, increased cellular load of R-loops and DSBs, which are normalized upon RNaseH1-mediated suppression of ectopic R-loops, inversely correlates with disease severity scores.
CONCLUSION: Transcriptional R-loop imbalance is a novel molecular defect etiologic in Th1-immunodeficiency and genomic-instability in WAS. The study proposes that cellular R-loop load could be used as a potential biomarker for monitoring symptom severity in the XLT-WAS clinical spectrum, and could be targeted therapeutically.

PMID: 29248492 [PubMed – as supplied by publisher]

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A delayed diagnosis of X-linked hyper IgM syndrome complicated with toxoplasmic encephalitis in a child: A case report and literature review.

Medicine (Baltimore). 2017 Dec;96(49):e8989

Authors: Liu X, Zhou K, Yu D, Cai X, Hua Y, Zhou H, Wang C

Abstract
INTRODUCTION: The X-linked hyper-immunoglobulin M syndrome (XHIGM) is an uncommon primary combined immunodeficiency disease caused by CD40L gene mutations. A delayed or missed diagnosis of XHIGM is common and concerning, owing to atypical immunoglobulin profile and phenotype of some patients, low recognition, and limited knowledge of clinicians on XHIGM in some underdeveloped areas. Opportunistic infections are a prominent clinical feature of XHIGM. However, toxoplasma encephalitis occurs sporadically and is extremely rare in patients with XHIGM.
DIAGNOSTIC AND THERAPEUTIC PROCEDURE: A 2 years and 10 months’ old male suffered from 3 times of serious infection since 1 year and 4 months of age. Although with history of recurrent respiratory infections, protracted diarrhea, persistent or intermittent neutropenia companioned with oral ulcer, and a typical immunoglobulin profile during his second disease attack, the consideration of XHIGM was still completely ignored because of our low recognition and limited knowledge of this disorder. The diagnosis of XHIGM was ultimately confirmed by detection of elevated serum IgM concentration, decreased serum IgG and IgE concentration, and identification of a mutation c.654C>A (p.C218X) in CD40L gene. Given clinical manifestation of lethargy, uncontrollable somnolence and ataxia, a cat/dog exposure history, positive serum Toxoplasma gondii (T gondii) IgM, positive cerebrospinal fluid T gondii PCR results, and typical characteristics of brain magnetic resonance imaging as multiple rings liked nodules lesions in bilateral cerebral hemisphere cortex, bilateral basal ganglia, and dorsal thalamus, the diagnosis of toxoplasmic encephalitis was considered during his third disease attack. Thereafter, oral administration of sulfadiazine and azithromycin, intravenous immunoglobulin, and subcutaneous injection of G-CSF were initiated. Regrettably, the patient abandoned the treatment because of economic factor and died 3 months after discharge.
CONCLUSIONS: A more thorough clinical history and some features like recurrent respiratory infections, protracted diarrhea, and persistent or intermittent neutropenia companioned with oral ulcer could increase clinical suspicion of XHIGM. Cerebral toxoplasmosis is rare in patients with XHIGM, but still should be considered. The present study firstly reported a delayed diagnosed case of XHIGM with CD40L gene c.654C>A (p.C218X) mutant complicated with toxoplasma encephalitis in Chinese population, which highlighted the importance of CD40-CD40L interaction in cell-mediated immunity against T gondii.

PMID: 29245273 [PubMed – in process]

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Long-term follow up of IPEX syndrome patients after different therapeutic strategies: an international multicenter retrospective study.

J Allergy Clin Immunol. 2017 Dec 11;:

Authors: Barzaghi F, Amaya Hernandez LC, Neven B, Ricci S, Kucuk ZY, Bleesing J, Nademi Z, Slatter MA, Ulloa ER, Shcherbina A, Roppelt A, Worth A, Silva J, Aiuti A, Murguia-Favela L, Speckmann C, Carneiro-Sampaio M, Fernandes JF, Baris S, Ozen A, Karakoc-Aydiner E, Kiykim A, Schulz A, Steinmann S, Notarangelo LD, Gambineri E, Lionetti P, Shearer WT, Forbes L, Martinez C, Moshous D, Blanche S, Fisher A, Ruemmele FM, Tissandier C, Ouachee-Chardin M, Rieux-Laucat F, Cavazzana M, Qasim W, Lucarelli B, Albert MH, Kobayashi I, Alonso L, Diaz De Heredia C, Kanegane H, Lawitschka A, Seo JJ, Gonzalez-Vicent M, Diaz MA, Goyal RK, Sauer MG, Yesilipek A, Kim M, Yilmaz-Demirdag Y, Bhatia M, Khlevner J, Richmond Padilla EJ, Martino S, Montin D, Neth O, Molinos-Quintana A, Valverde-Fernandez J, Broides A, Pinsk V, Ballauf A, Haerynck F, Bordon V, Dhooge C, Garcia-Lloret ML, Bredius RG, Kałwak K, Haddad E, Seidel MG, Duckers G, Pai SY, Dvorak CC, Ehl S, Locatelli F, Goldman F, Gennery AR, Cowan MJ, Roncarolo MG, Bacchetta R, PIDTC and IEWP of EBMT

Abstract
BACKGROUND: Immunedysregulation Polyendocrinopathy Enteropathy X-linked (IPEX) syndrome is a monogenic autoimmune disease caused by FOXP3 mutations. Because it is a rare disease, the natural history and response to treatments, including allogeneic hematopoietic stem cell transplantation (HSCT) and immunosuppression (IS), have not been thoroughly examined.
OBJECTIVE: To evaluate disease onset, progression and long-term outcome of the two main treatments in long-term IPEX survivors.
METHODS: Clinical histories of 96 patients with a genetically proven IPEX syndrome were collected from 38 institutions worldwide and retrospectively analyzed. To investigate possible factors suitable to predict the outcome, an organ involvement (OI) scoring system was developed.
RESULTS: We confirm neonatal onset with enteropathy, type 1 diabetes (T1D), and eczema. In addition, we found less common manifestations in delayed onset patients or during disease evolution. There is no correlation between the site of mutation and the disease course or outcome, and the same genotype can present with variable phenotypes. HSCT patients (n=58) had a median follow-up of 2.7 years (range: 1 week – 15 years). Patients receiving chronic IS (n=34) had a median follow-up of 4 years (range: 2 months – 25 years). The overall survival (OS) after HSCT was 73.2% (95% confidence interval [CI], 59.4 to 83.0) and after IS was 65.1% (95 % CI, 62.8 to 95.8). The pre-treatment OI score was the only significant predictor of OS after transplant (p=0.035) but not under IS.
CONCLUSIONS: Patients receiving chronic IS were hampered by disease recurrence or complications, impacting long-term disease-free survival. When performed in patients with a low OI score, HSCT resulted in disease resolution with better quality of life, independent of age, donor source or conditioning regimen.

PMID: 29241729 [PubMed – as supplied by publisher]

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Hematopoietic stem cell gene therapy for IFNγR1 deficiency protects mice from mycobacterial infections.

Blood. 2017 Dec 12;:

Authors: Hetzel M, Mucci A, Blank P, Nguyen AHH, Schiller J, Halle O, Kühnel MP, Billig S, Meineke R, Brand D, Herder V, Baumgärtner W, Bange FC, Goethe R, Jonigk D, Förster R, Gentner B, Casaova JL, Bustamante J, Schambach A, Kalinke U, Lachmann N

Abstract
Mendelian Susceptibility to Mycobacterial Disease (MSMD) is a rare primary immunodeficiency, characterized by severe infections caused by weakly virulent mycobacteria. Bi-allelic null mutations in genes encoding interferon gamma (IFNγ) receptor 1 or -2 (IFNGR1, IFNGR2) result in a life-threatening disease phenotype in early childhood. Recombinant IFNγ therapy is inefficient and hematopoietic stem cell transplantation (HSCT) has a poor prognosis. Thus, we developed a HSC gene therapy approach using lentiviral vectors expressing Ifnγr1 either constitutively or myeloid-specifically. Transduction of mouse Ifnγr1-/- HSCs led to stable IFNγR1 expression on macrophages, which rescued their cellular responses to IFNγ. As a consequence, genetically corrected HSC-derived macrophages were able to suppress T-cell activation and showed restored anti-mycobacterial activity against Mycobacterium avium and Mycobacterium bovis Bacillus-Calmette-Guérin (BCG) in vitro Transplantation of genetically corrected HSC into Ifnγr1-/- mice prior BCG infection prevented manifestations of severe BCG disease and maintained lung and spleen organ integrity, which was accompanied by a reduced mycobacterial burden in lung and spleen and a prolonged overall survival of transplanted animals. In summary, we demonstrate an HSC-based gene therapy approach for IFNγR1 deficiency, which protects mice from severe mycobacterial infections, thereby laying the foundation for a new therapeutic intervention in the corresponding human patients.

PMID: 29233822 [PubMed – as supplied by publisher]

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Exome Sequencing Identifies a Novel MAP3K14 Mutation in Recessive Atypical Combined Immunodeficiency.

Front Immunol. 2017;8:1624

Authors: Schlechter N, Glanzmann B, Hoal EG, Schoeman M, Petersen BS, Franke A, Lau YL, Urban M, van Helden PD, Esser MM, Möller M, Kinnear C

Abstract
Primary immunodeficiency disorders (PIDs) render patients vulnerable to infection with a wide range of microorganisms and thus provide good in vivo models for the assessment of immune responses during infectious challenges. Priming of the immune system, especially in infancy, depends on different environmental exposures and medical practices. This may determine the timing and phenotype of clinical appearance of immune deficits as exemplified with early exposure to Bacillus Calmette-Guérin (BCG) vaccination and dissemination in combined immunodeficiencies. Varied phenotype expression poses a challenge to identification of the putative immune deficit. Without the availability of genomic diagnosis and data analysis resources and with limited capacity for functional definition of immune pathways, it is difficult to establish a definitive diagnosis and to decide on appropriate treatment. This study describes the use of exome sequencing to identify a homozygous recessive variant in MAP3K14, NIKVal345Met, in a patient with combined immunodeficiency, disseminated BCG-osis, and paradoxically elevated lymphocytes. Laboratory testing confirmed hypogammaglobulinemia with normal CD19, but failed to confirm a definitive diagnosis for targeted treatment decisions. NIKVal345Met is predicted to be deleterious and pathogenic by two in silico prediction tools and is situated in a gene crucial for effective functioning of the non-canonical nuclear factor-kappa B signaling pathway. Functional analysis of NIKVal345Met- versus NIKWT-transfected human embryonic kidney-293T cells showed that this mutation significantly affects the kinase activity of NIK leading to decreased levels of phosphorylated IkappaB kinase-alpha (IKKα), the target of NIK. BCG-stimulated RAW264.7 cells transfected with NIKVal345Met also presented with reduced levels of phosphorylated IKKα, significantly increased p100 levels and significantly decreased p52 levels compared to cells transfected with NIKWT. Ideally, these experiments would have been conducted in patient-derived immune cells, but we were unable to source these cells from the patient. The functional analysis described in this paper supports previous illustrations of the importance of NIK in human immune responses and demonstrates the involvement of function-altering mutations in MAP3K14 in PIDs. The genomic approach used for this patient demonstrates its value in the diagnosis of an unusual PID and as a tool for detecting rarer mutations to help guide treatment approaches.

PMID: 29230214 [PubMed]

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Immunogenicity and safety of inactivated chromatographically purified Vero cell-derived Japanese encephalitis vaccine in Thai children.

Hum Vaccin Immunother. 2017 Dec 11;:0

Authors: Chanthavanich P, Limkittikul K, Sirivichayakul C, Chokejindachai W, Hattasingh W, Pengsaa K, Surangsrirat S, Srisuwannaporn T, Kaewma B, Yoksan S, Jun G, Zhumu B

Abstract
Inactivated mouse-brain-derived Japanese encephalitis vaccine has a worrisome safety profile and the live attenuated vaccine is unsuitable in immunodeficiency. This study aimed to evaluate the immunogenicity and safety of an inactivated chromatographically purified Vero-cell-derived JE vaccine (CVI-JE, Beijing P-3 strain) in children. 152 healthy Thai children, with an average (SD) age of 14.4 (3.8) months, received 3 doses of CVI-JE on days 0, 7-28, and one year. Homologous JE neutralizing antibody titers (NT) were measured. All subjects had seroprotection [geometric mean titer (GMT) 150] 28 days’ post 2nd vaccination. The seroprotection rates at 1 year after primary series and and 1 month after the booster were 89.3% (GMT 49) and 100% (GMT 621), respectively. Local and systemic reactions-fever (17.6%), vomiting (8%), and poor appetite (5.3%)-were noted within 28 days’ post-vaccination. All these symptoms were self-limited.
CONCLUSIONS: CVI-JE is safe, immunogenic, and provided high NT.

PMID: 29227177 [PubMed – as supplied by publisher]

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International Union of Immunological Societies: 2017 Primary Immunodeficiency Diseases Committee Report on Inborn Errors of Immunity.

J Clin Immunol. 2017 Dec 11;:

Authors: Picard C, Bobby Gaspar H, Al-Herz W, Bousfiha A, Casanova JL, Chatila T, Crow YJ, Cunningham-Rundles C, Etzioni A, Franco JL, Holland SM, Klein C, Morio T, Ochs HD, Oksenhendler E, Puck J, Tang MLK, Tangye SG, Torgerson TR, Sullivan KE

Abstract
Beginning in 1970, a committee was constituted under the auspices of the World Health Organization (WHO) to catalog primary immunodeficiencies. Twenty years later, the International Union of Immunological Societies (IUIS) took the remit of this committee. The current report details the categorization and listing of 354 (as of February 2017) inborn errors of immunity. The growth and increasing complexity of the field have been impressive, encompassing an increasing variety of conditions, and the classification described here will serve as a critical reference for immunologists and researchers worldwide.

PMID: 29226302 [PubMed – as supplied by publisher]

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Fatal CTLA-4 heterozygosity with autoimmunity and recurrent infections: a de novo mutation.

Clin Case Rep. 2017 Dec;5(12):2066-2070

Authors: Moraes-Fontes MF, Hsu AP, Caramalho I, Martins C, Araújo AC, Lourenço F, Taulaigo AV, Lladó A, Holland SM, Uzel G

Abstract
Primary immunodeficiency disorders are rarely diagnosed in adults but must be considered in the differential diagnosis of combined recurrent infections and autoimmune disease. We describe a patient with CTLA-4 haploinsufficiency and an abnormal regulatory T-cell phenotype. Unusually, infections were more severe than autoimmunity, illustrating therapeutic challenges in disease course.

PMID: 29225858 [PubMed]

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