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Family-Based Next-Generation Sequencing Study Identifies an IL2RG Variant in an Infant with Primary Immunodeficiency.

OMICS. 2019 May;23(5):285-290

Authors: Bandari AK, Bhat S, Archana MV, Yadavalli S, Patel K, Rajagopalan P, Madugundu AK, Madkaikar M, Reddy K, Muthusamy B, Pandey A

Abstract
Primary immunodeficiencies (PIDs) are a rare and heterogeneous group of inherited genetic disorders that are characterized by an absent or impaired immune system. In this report, we describe the use of next-generation sequencing to investigate a male infant with clinical and immunological manifestations suggestive of a PID. Whole-exome sequencing of the infant along with his parents revealed a novel nucleotide variant (cytosine to adenine substitution at nucleotide position 252) in the coding region of the interleukin 2 receptor subunit gamma (IL2RG) gene. The mother was found to be a carrier. These findings are consistent with a diagnosis of X-linked severe combined immunodeficiency and represent the first such reported mutation in an Indian family. This mutation leads to an asparagine to lysine substitution ( p.Asn84Lys ) located in the extracellular domain of IL2RG, which is predicted to be pathogenic. Our study demonstrates the power of next-generation sequencing in identifying potential causative mutations to enable accurate clinical diagnosis, prenatal screening, and carrier female detection in PID patients. We believe that this approach, which is not a current routine in clinical practice, will become a mainstream component of individualized medicine in the near future.

PMID: 31100039 [PubMed – in process]

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Switching immunoglobulin products, what are the implications? Result of 2018 census of immunology centres.

Clin Med (Lond). 2019 May;19(3):201-204

Authors: Bethune C, Herriot R

Abstract
The use of regular infusions of immunoglobulin is well established as a treatment for patients with antibody deficiency and for patients requiring immunomodulation. Although efficacy is believed to be equivalent for the different immunoglobulin products, it is generally regarded as best practice not to switch from one product to another unless there is a clinical reason to change. Changes in commissioning guidance and issues with the supply of some immunoglobulin products to the UK resulted in a requirement for a significant number of patients to switch between immunoglobulin products in 2017-2018. Data from the 2018 UK Primary Immunodeficiency census has been used to evaluate the clinical results of switching. Results from 30 immunology centres reported a total of 802 immunoglobulin product switches. Twelve reactions were recorded, none of which required admission to hospital, one patient was treated with oral corticosteroids, the others required either no treatment or treatment with oral antihistamines. This review of immunoglobulin product switch reactions gives a clearer indication regarding the safety of product switching than has previously been published.

PMID: 31092511 [PubMed – in process]

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The Heterogeneous Pathogenesis of Selective Immunoglobulin A Deficiency.

Int Arch Allergy Immunol. 2019 May 15;:1-15

Authors: Bagheri Y, Sanaei R, Yazdani R, Shekarabi M, Falak R, Mohammadi J, Abolhassani H, Aghamohammadi A

Abstract
Selective immunoglobulin A deficiency (SIgAD) is the most prevalent type of primary immunodeficiency disorder. The phenotypic feature of SIgAD is related to a defect in B lymphocyte differentiation into plasma cell-producing immunoglobulin A (IgA). In this review, we summarize the recent advances in this regard. Genetic (including major histocompatibility complex [MHC] and non-MHC genes), immunologic (including B and T lymphocyte subsets abnormality), cytokines/chemokines and their related receptors, apoptosis and microbiota defects are reviewed. The mechanisms leading to SIgAD are most likely multifactorial and it can be speculated that several pathways controlling B cells functions or regulating epigenetic of the IGHA gene encoding constant region of IgA heavy chain and long-term survival of IgA switched memory B cells and plasma cells may be defective in different SIgAD patients.

PMID: 31091523 [PubMed – as supplied by publisher]

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Factors Beyond Lack of Antibody Govern Pulmonary Complications in Primary Antibody Deficiency.

J Clin Immunol. 2019 May 14;:

Authors: Weinberger T, Fuleihan R, Cunningham-Rundles C, Maglione PJ

Abstract
PURPOSE: Pulmonary complications occur frequently in primary antibody deficiency (PAD). While the impact of antibody deficiency may appear implicit for certain respiratory infections, immunoglobulin replacement therapy does not completely ameliorate pulmonary complications in PAD. Thus, there may be antibody-independent factors influencing susceptibility to respiratory disease in PAD, but these remain incompletely defined.
METHODS: We harnessed the multicenter US Immunodeficiency Network primary immunodeficiency registry to compare prevalence of asthma, bronchiectasis, interstitial lung disease (ILD), and respiratory infections between two forms of PAD: common variable immunodeficiency (CVID) and x-linked agammaglobulinemia (XLA). We also defined the clinical and immunological characteristics associated with ILD and asthma in CVID.
RESULTS: Asthma, bronchiectasis, ILD, pneumonia, and upper respiratory infections were more prevalent in CVID than XLA. ILD was associated with autoimmunity, bronchiectasis, and pneumonia as well as fewer B and T cells in CVID. Asthma was the most common chronic pulmonary complication and associated with lower IgA and IgM in CVID. Age of symptom onset or CVID diagnosis was unrelated with ILD or asthma.
CONCLUSION: Despite having less severe immunoglobulin deficiency than XLA, respiratory infections, ILD, and asthma were more common in CVID. Among CVID patients, ILD was associated with autoimmunity and reduced lymphocytes and asthma with lower immunoglobulins. Though our results are tempered by registry limitations, they provide evidence that factors beyond lack of antibody promote pulmonary complications in PAD. Efforts to understand how genetic etiology, nature of concurrent T cell deficiency, and propensity for autoimmunity shape pulmonary disease may improve treatment of PAD.

PMID: 31089938 [PubMed – as supplied by publisher]

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Idiopathic, Refractory Sweet’s Syndrome Associated with Common Variable Immunodeficiency: a Case Report and Literature Review.

Curr Allergy Asthma Rep. 2019 May 14;19(6):32

Authors: Cook QS, Zdanski CJ, Burkhart CN, Googe PB, Thompson P, Wu EY

Abstract
PURPOSE OF REVIEW: Sweet’s syndrome (SS) is classically considered a hypersensitivity reaction often associated with autoimmune disorders and malignancy. SS has also been increasingly reported to occur with immunodeficiencies. We present a case of treatment-refractory, systemic SS as the initial manifestation in a young child with common variable immunodeficiency (CVID). We also review current literature about SS and concurrent immunodeficiencies and autoimmunity in CVID patients.
RECENT FINDINGS: Few case reports exist regarding the co-occurrence of Sweet’s syndrome and primary immunodeficiencies. SS is characterized by a pro-inflammatory state with a neutrophil predominance resulting in a spectrum of clinical manifestations. CVID is a multifactorial antibody deficiency that can be associated with autoimmunity, which some studies have proposed to be secondary to altered CD21 expression. SS occurring in patients with CVID has been infrequently reported, and one case study demonstrated improvement of Sweet’s associated skin lesions with immunoglobulin replacement. In our case, the patient had multi-system SS refractory to multiple immunomodulatory therapies. To our knowledge, this is the first report of the effective and safe use of intravenous tocilizumab and oral lenalidomide to treat SS in a child with CVID. Immunoglobulin replacement reduced the frequency of infections and may have contributed to the opportunity to wean the immunosuppressive therapies for Sweet’s syndrome. Sweet’s syndrome as an initial manifestation of co-occurring immunodeficiencies is rare, and providers need a high index of suspicion. In addition, treatment of SS associated with an immunodeficiency can be a challenge. Treatment with immunoglobulin replacement reduces the frequency of infections, and in some patients with concurrent SS may improve skin lesions and reduce the need for immunomodulator therapy. Further study is necessary to better understand the pathogenesis of CVID in patients with SS and to identify possible biomarkers that predict who with SS are at risk for developing hypogammaglobulinemia.

PMID: 31089823 [PubMed – in process]

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Targeted Delivery of Curcumin Rescues Endoplasmic Reticulum-Retained Mutant NOX2 Protein and Avoids Leukocyte Apoptosis.

J Immunol. 2019 May 13;:

Authors: Yen CL, Liao YC, Chen RF, Huang YF, Chung WC, Lo PC, Chang CF, Wu PC, Shieh DB, Jiang ST, Shieh CC

Abstract
Chronic granulomatous disease (CGD) is a primary immunodeficiency disease caused by defects in the leukocyte NADP oxidase. We previously reported that sarcoplasmic/endoplasmic reticulum calcium pump (SERCA) inhibitors could be used to rescue mutant H338Y-gp91phox protein of a particular type of CGD with a CybbC1024T mutation, leading to endoplasmic reticulum (ER) retention of the mutant protein. In this study, we developed a novel mouse model with the CybbC1024T mutation on a Cybb knockout background and investigated the therapeutic effects of ER-targeted delivery of the SERCA inhibitor, curcumin, with poly(lactic-coglycolic acid) (PLGA) nanoparticles (NPs). We found that PLGA encapsulation improved the efficacy of curcumin as a SERCA inhibitor to induce ER calcium release. ER-targeting curcumin-loaded PLGA NPs reduced and delayed extracellular calcium entry and protected the cells from mitochondrial damage and apoptosis. In vivo studies showed that ER-targeting curcumin-loaded PLGA NPs treatment enhanced neutrophil gp91phox expression, ROS production and peritoneal bacterial clearance ability of the CybbC1024T transgenic Cybb -/- mice. Our findings indicate that ER-targeted delivery of curcumin not only rescues ER-retained H338Y-gp91phox protein, and hence leukocyte function, but also enhances the bioavailability and reduces cytotoxicity. Modulation of ER function by using organelle-targeted NPs may be a promising strategy to improve the therapeutic potential of curcumin as a treatment for CGD.

PMID: 31085592 [PubMed – as supplied by publisher]

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Immunosuppressive therapy with rituximab in common variable immunodeficiency.

Clin Mol Allergy. 2019;17:9

Authors: Pecoraro A, Crescenzi L, Galdiero MR, Marone G, Rivellese F, Rossi FW, de Paulis A, Genovese A, Spadaro G

Abstract
Common variable immunodeficiency (CVID) is the most frequent symptomatic primary antibody deficiency in adulthood and is characterized by the marked reduction of IgG and IgA serum levels. Thanks to the successful use of polyvalent immunoglobulin replacement therapy to treat and prevent recurrent infections, non-infectious complications, including autoimmunity, polyclonal lymphoproliferation and malignancies, have progressively become the major cause of morbidity and mortality in CVID patients. The management of these complications is particularly challenging, often requiring multiple lines of immunosuppressive treatments. Over the last 5-10 years, the anti-CD20 monoclonal antibody (i.e., rituximab) has been increasingly used for the treatment of both autoimmune and non-malignant lymphoproliferative manifestations associated with CVID. This review illustrates the evidence on the use of rituximab in CVID. For this purpose, first we discuss the mechanisms proposed for the rituximab mediated B-cell depletion; then, we analyze the literature data regarding the CVID-related complications for which rituximab has been used, focusing on autoimmune cytopenias, granulomatous lymphocytic interstitial lung disease (GLILD) and non-malignant lymphoproliferative syndromes. The cumulative data suggest that in the vast majority of the studies, rituximab has proven to be an effective and relatively safe therapeutic option. However, there are currently no data on the long-term efficacy and side effects of rituximab and other second-line therapeutic options. Further randomized controlled trials are needed to optimize the management strategies of non-infectious complications of CVID.

PMID: 31080365 [PubMed]

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A nearly fatal primary Epstein-Barr virus infection associated with low NK-cell counts in a patient receiving azathioprine: a case report and review of literature.

BMC Infect Dis. 2019 May 10;19(1):404

Authors: Honkila M, Niinimäki R, Taskinen M, Kuismin O, Kettunen K, Saarela J, Turunen S, Renko M, Tapiainen T

Abstract
BACKGROUND: Symptomatic primary Epstein-Barr virus infection is a usually self-limiting illness in adolescents. We present a case of an adolescent who had been receiving azathioprine for inflammatory bowel disease for four years and developed a life-threatening primary Epstein-Barr virus infection successfully treated with rituximab.
CASE PRESENTATION: An 11-year-old girl presented with chronic, bloody diarrhea. Endoscopic biopsies confirmed a diagnosis of chronic ulcerative colitis with features of Crohn’s disease. Azathioprine was initiated after one year due to active colitis. She responded well and remission was achieved. At the age of 16 years she developed a life-threatening Epstein-Barr virus infection including severe multiple organ failure and was critically ill for 4 weeks in the intensive care unit. Natural killer cells were virtually absent in the lymphocyte subset analysis. Azathioprine was stopped on admission. She was initially treated with corticosteroids, acyclovir and intravenous immunoglobulin. Approximately 30 days after admission, she developed signs of severe hepatitis and pneumonitis and received weekly rituximab infusions for 8 weeks. Primary immunodeficiency was excluded by whole exome sequencing in two independent laboratories. Persistent viremia stopped when the natural killer cell count started to rise, approximately 90 days after the cessation of azathioprine.
CONCLUSIONS: We found 17 comparable cases in the literature. None of the previous cases reported in the literature, who had been treated with azathioprine and developed either a severe or a fatal Epstein-Barr virus infection, underwent full genetic and prospective immunological workup to rule out known primary immunodeficiencies. Recently, azathioprine has been shown to cause rather specific immunosuppression, resulting in natural killer cell depletion. Our case demonstrates that slow recovery from azathioprine-induced natural killer cell depletion, 3 months after the stopping of azathioprine, coincided with the clearance of viremia and clinical recovery. Finally, our choice of treating the patient with rituximab, as previously used for patients with a severe immunosuppression and Epstein-Barr virus viremia, appeared to be successful in this case. We suggest testing for Epstein-Barr virus serology before starting azathioprine and measuring natural killer cell counts during the treatment to identify patients at risk of developing an unusually severe primary Epstein-Barr virus infection.

PMID: 31077135 [PubMed – in process]

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