Research

Hetero-oligomerization between the TNF receptor superfamily members CD40, Fas and TRAILR2 modulate CD40 signalling.

Cell Death Dis. 2017 Feb 09;8(2):e2601

Authors: Smulski CR, Decossas M, Chekkat N, Beyrath J, Willen L, Guichard G, Lorenzetti R, Rizzi M, Eibel H, Schneider P, Fournel S

Abstract
TNF receptor superfamily members (TNFRSF) such as CD40, Fas and TRAIL receptor 2 (TRAILR2) participate to the adaptive immune response by eliciting survival, proliferation, differentiation and/or cell death signals. The balance between these signals determines the fate of the immune response. It was previously reported that these receptors are able to self-assemble in the absence of ligand through their extracellular regions. However, the role of this oligomerization is not well understood, and none of the proposed hypotheses take into account potential hetero-association of receptors. Using CD40 as bait in a flow cytometry Förster resonance energy transfer assay, TNFRSF members with known functions in B cells were probed for interactions. Both Fas and TRAILR2 associated with CD40. Immunoprecipitation experiments confirmed the interaction of CD40 with Fas at the endogenous levels in a BJAB B-cell lymphoma cell line deficient for TRAILR2. TRAILR2-expressing BJAB cells displayed a robust CD40-TRAILR2 interaction at the expense of the CD40-Fas interaction. The same results were obtained by proximity ligation assay, using TRAILR2-positive and -negative BJAB cells and primary human B cells. Expression of the extracellular domains of Fas or TRAILR2 with a glycolipid membrane anchor specifically reduced the intrinsic signalling pathway of CD40 in 293T cells. Conversely, BJAB cells lacking endogenous Fas or TRAILR2 showed an increased NF-κB response to CD40L. Finally, upregulation of TRAILR2 in primary human B cells correlated with reduced NF-κB activation and reduced proliferation in response to CD40L. Altogether, these data reveal that selective interactions between different TNFRSF members may modulate ligand-induced responses upstream signalling events.

PMID: 28182009 [PubMed – in process]

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A multi-institutional comparison of outcomes of immunosuppressed and immunocompetent patients treated with surgery and radiation therapy for cutaneous squamous cell carcinoma of the head and neck.

Cancer. 2017 Feb 07;:

Authors: Manyam BV, Garsa AA, Chin RI, Reddy CA, Gastman B, Thorstad W, Yom SS, Nussenbaum B, Wang SJ, Vidimos AT, Koyfman SA

Abstract
BACKGROUND: Patients who are chronically immunosuppressed have higher rates of cutaneous squamous cell carcinoma of the head and neck (cSCC-HN). This is the largest multi-institutional study to date investigating the effect of immune status on disease outcomes in patients with cSCC-HN who underwent surgery and received postoperative radiation therapy (RT).
METHODS: Patients from 3 institutions who underwent surgery and also received postoperative RT for primary or recurrent, stage I through IV cSCC-HN between 1995 and 2015 were included in this institutional review board-approved study. Patients categorized as immunosuppressed had chronic hematologic malignancy, human immunodeficiency/acquired immunodeficiency syndrome, or had received immunosuppressive therapy for organ transplantation ≥6 months before diagnosis. Overall survival, locoregional recurrence-free survival, and progression-free survival were calculated using the Kaplan-Meier method. Univariate and multivariate analyses were performed using Cox proportional-hazards regression.
RESULTS: Of 205 patients, 138 (67.3%) were immunocompetent, and 67 (32.7%) were immunosuppressed. Locoregional recurrence-free survival (47.3% vs 86.1%; P < .0001) and progression-free survival (38.7% vs 71.6%; P = .002) were significantly lower in immunosuppressed patients at 2 years. The 2-year OS rate in immunosuppressed patients demonstrated a similar trend (60.9% vs 78.1%; P = .135) but did not meet significance. On multivariate analysis, immunosuppressed status (hazard ratio [HR], 3.79; P < .0001), recurrent disease (HR, 2.67; P = .001), poor differentiation (HR, 2.08; P = .006), and perineural invasion (HR, 2.05; P = .009) were significantly associated with locoregional recurrence.
CONCLUSIONS: Immunosuppressed patients with cSCC-HN had dramatically lower outcomes compared with immunocompetent patients, despite receiving bimodality therapy. Immune status is a strong prognostic factor that should be accounted for in prognostic systems, treatment algorithms, and clinical trial design. Cancer 2017. © 2017 American Cancer Society.

PMID: 28171708 [PubMed – as supplied by publisher]

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Conformational disruption of PI3Kδ regulation by immunodeficiency mutations in PIK3CD and PIK3R1.

Proc Natl Acad Sci U S A. 2017 Feb 06;:

Authors: Dornan GL, Siempelkamp BD, Jenkins ML, Vadas O, Lucas CL, Burke JE

Abstract
Activated PI3K Delta Syndrome (APDS) is a primary immunodeficiency disease caused by activating mutations in either the leukocyte-restricted p110δ catalytic (PIK3CD) subunit or the ubiquitously expressed p85α regulatory (PIK3R1) subunit of class IA phosphoinositide 3-kinases (PI3Ks). There are two classes of APDS: APDS1 that arises from p110δ mutations that are analogous to oncogenic mutations found in the broadly expressed p110α subunit and APDS2 that occurs from a splice mutation resulting in p85α with a central deletion (Δ434-475). As p85 regulatory subunits associate with and inhibit all class IA catalytic subunits, APDS2 mutations are expected to similarly activate p110α, β, and δ, yet APDS2 largely phenocopies APDS1 without dramatic effects outside the immune system. We have examined the molecular mechanism of activation of both classes of APDS mutations using a combination of biochemical assays and hydrogen-deuterium exchange mass spectrometry. Intriguingly, we find that an APDS2 mutation in p85α leads to substantial basal activation of p110δ (>300-fold) and disrupts inhibitory interactions from the nSH2, iSH2, and cSH2 domains of p85, whereas p110α is only minimally basally activated (∼2-fold) when associated with mutated p85α. APDS1 mutations in p110δ (N334K, E525K, E1021K) mimic the activation mechanisms previously discovered for oncogenic mutations in p110α. All APDS mutations were potently inhibited by the Food and Drug Administration-approved p110δ inhibitor idelalisib. Our results define the molecular basis of how PIK3CD and PIK3R1 mutations result in APDS and reveal a potential path to treatment for all APDS patients.

PMID: 28167755 [PubMed – as supplied by publisher]

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Coronary atherosclerosis and dilation in hyper IgE syndrome patients: Depiction by magnetic resonance vessel wall imaging and pathological correlation.

Atherosclerosis. 2017 Jan 19;258:20-25

Authors: Abd-Elmoniem KZ, Ramos N, Yazdani SK, Ghanem AM, Holland SM, Freeman AF, Gharib AM

Abstract
BACKGROUND AND AIMS: Autosomal dominant hyper-IgE (AD-HIES) is a primary immunodeficiency caused by mutations in STAT3. Elevated levels of IgE, an ineffective immune response, connective tissue abnormalities, and coronary arterial dilation and tortuosity characterize AD-HIES. To date, coronary artery evaluation in AD-HIES patients has been limited to lumenography measurements. Direct in vivo coronary vessel wall (VW) imaging may allow for better interrogation of coronary vessel abnormalities. The goal of this prospective study was to evaluate the coronary VW of AD-HIES patients using Magnetic Resonance Imaging (MRI) and histology. VW image findings were compared in healthy subjects and subjects with coronary atherosclerotic disease (CAD).
METHODS: A total of 28 subjects (10 with AD-HIES, 8 healthy, 10 with CAD) were studied by coronary VW MRI imaging. Additionally, a post-mortem coronary artery from one VW imaged AD-HIES patient was examined.
RESULTS: Coronary VW in AD-HIES was thicker than in healthy controls but not significantly different from VW thickness in CAD subjects. AD-HIES coronaries showed increased VW area compared to healthy controls and CAD subjects. On histology, the AD-HIES coronary artery had findings consistent with atherosclerotic plaque, but had minimal luminal narrowing, deficient adventitia thickening and absence of both internal and external elastic laminae.
CONCLUSIONS: This is the first study to demonstrate subclinical coronary atherosclerosis in AD-HIES patients on VW imaging by MRI. Histologic evaluation confirmed the presence of atherosclerosis with lack of supportive adventitial thickening and elastic components. These findings suggest mechanisms for coronary dilation in AD-HIES and thereby help direct clinical management.

PMID: 28167354 [PubMed – as supplied by publisher]

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FDG PET/CT Findings of Primary Hepatic Leiomyosarcoma in an Immunocompetent Pediatric Patient.

Clin Nucl Med. 2017 Feb 04;:

Authors: Xie P, Zhuang H

Abstract
Primary hepatic leiomyosarcoma generally occurs only in adult patients or pediatric patients with immunodeficiency. We report here the FDG PET/CT findings of primary hepatic leiomyosarcoma in a 10-year-old immunocompetent girl.

PMID: 28166141 [PubMed – as supplied by publisher]

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Genome-wide association analysis implicates dysregulation of immunity genes in chronic lymphocytic leukaemia.

Nat Commun. 2017 Feb 06;8:14175

Authors: Law PJ, Berndt SI, Speedy HE, Camp NJ, Sava GP, Skibola CF, Holroyd A, Joseph V, Sunter NJ, Nieters A, Bea S, Monnereau A, Martin-Garcia D, Goldin LR, Clot G, Teras LR, Quintela I, Birmann BM, Jayne S, Cozen W, Majid A, Smedby KE, Lan Q, Dearden C, Brooks-Wilson AR, Hall AG, Purdue MP, Mainou-Fowler T, Vajdic CM, Jackson GH, Cocco P, Marr H, Zhang Y, Zheng T, Giles GG, Lawrence C, Call TG, Liebow M, Melbye M, Glimelius B, Mansouri L, Glenn M, Curtin K, Diver WR, Link BK, Conde L, Bracci PM, Holly EA, Jackson RD, Tinker LF, Benavente Y, Boffetta P, Brennan P, Maynadie M, McKay J, Albanes D, Weinstein S, Wang Z, Caporaso NE, Morton LM, Severson RK, Riboli E, Vineis P, Vermeulen RC, Southey MC, Milne RL, Clavel J, Topka S, Spinelli JJ, Kraft P, Ennas MG, Summerfield G, Ferri GM, Harris RJ, Miligi L, Pettitt AR, North KE, Allsup DJ, Fraumeni JF, Bailey JR, Offit K, Pratt G, Hjalgrim H, Pepper C, Chanock SJ, Fegan C, Rosenquist R, de Sanjose S, Carracedo A, Dyer MJ, Catovsky D, Campo E, Cerhan JR, Allan JM, Rothman N, Houlston R, Slager S

Abstract
Several chronic lymphocytic leukaemia (CLL) susceptibility loci have been reported; however, much of the heritable risk remains unidentified. Here we perform a meta-analysis of six genome-wide association studies, imputed using a merged reference panel of 1,000 Genomes and UK10K data, totalling 6,200 cases and 17,598 controls after replication. We identify nine risk loci at 1p36.11 (rs34676223, P=5.04 × 10(-13)), 1q42.13 (rs41271473, P=1.06 × 10(-10)), 4q24 (rs71597109, P=1.37 × 10(-10)), 4q35.1 (rs57214277, P=3.69 × 10(-8)), 6p21.31 (rs3800461, P=1.97 × 10(-8)), 11q23.2 (rs61904987, P=2.64 × 10(-11)), 18q21.1 (rs1036935, P=3.27 × 10(-8)), 19p13.3 (rs7254272, P=4.67 × 10(-8)) and 22q13.33 (rs140522, P=2.70 × 10(-9)). These new and established risk loci map to areas of active chromatin and show an over-representation of transcription factor binding for the key determinants of B-cell development and immune response.

PMID: 28165464 [PubMed – in process]

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Inflammatory Duodenal Polyposis Associated with Primary Immunodeficiency Disease: A Novel Case Report.

Case Rep Med. 2017;2017:6206085

Authors: Shera IA, Khurshid SM, Bhat MS

Abstract
Agammaglobulinemia is a rare form of B-cell primary immunodeficiency disease characterized by reduced levels of IgG, IgA, or IgM and recurrent bacterial infections. Agammaglobulinemia is most commonly associated with diffuse nodular lymphoid hyperplasia. Duodenal polyps are a rare entity; however, due to wide use of esophagogastroduodenoscopy, incidental diagnosis of duodenal polyps appears to be increasing. Although inflammatory duodenal polyposis has been reported in the literature, its association with common variable immunodeficiency has not been reported till date to the best of our knowledge. We report a case of a 59-year-old male with chronic symptoms of agammaglobulinemia associated with inflammatory duodenal polyposis.

PMID: 28163721 [PubMed]

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The Clinical Significance of Complete Class Switching Defect in Ataxia Telangiectasia Patients.

Expert Rev Clin Immunol. 2017 Feb 04;:

Authors: Ghiasy S, Parvaneh L, Azizi G, Sadri G, Zaki Dizaji M, Abolhassani H, Aghamohammadi A

Abstract
OBJECTIVES: Ataxia telangiectasia (AT) is a primary immunodeficiency associated with recurrent infections. We aimed to investigate clinical and immunological classification in AT patients who suffer from a different spectrum of humoral immune defects.
METHODS: AT patients were categorized according to the ability of class switching and patients with hyper IgM (HIgM) profile were defined as class switching defect (CSD).
RESULTS: Serum immunoglobulin profile in 66 AT patients showed normal immunoglobulin level (22.8%), IgA deficiency (37.9%) and hypogammaglobulinemia (18.1%) in the majority of patients, while 21.2% had HIgM profile revealing CSD. CSD does not affect the frequency of infections, however, the frequency of lymphoproliferation (p<0.001), and autoimmunity (p=0.004) were significantly higher in this group. Neurologic symptoms in CSD patients are mild or appear after recurrent infections, therefore these patients were usually misdiagnosed as HIgM syndrome.
CONCLUSION: Although most of AT patients have reduced IgA levels or normal immunoglobulin levels, but a fraction of these patients may show CSD ensuing HIgM-profile. CSD poses affected individuals at higher risk of non-infectious complications.

PMID: 28162005 [PubMed – as supplied by publisher]

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A novel mutation in TAP1 gene leading to MHC class I deficiency: Report of two cases and review of the literature.

Clin Immunol. 2017 Feb 01;:

Authors: Hanalioglu D, Ayvaz DC, Ozgur TT, van der Burg M, Sanal O, Tezcan I

Abstract
Major histocompatibility complex (MHC) class I deficiency syndrome is a rare primary immunodeficiency caused by mutations in the peptide transporter complex associated with antigen presentation (TAP) gene which plays a crucial role in intracellular peptide antigen presentation. A few cases have been reported to date. Recurrent sinopulmonary infections and skin ulcers are main characteristics of the syndrome. Here we report two siblings diagnosed with TAP1 deficiency syndrome associated only with recurrent sinopulmonary infections with the description of a novel mutation leading to a premature stop codon in TAP1 gene and review of the relevant literature. Both of the siblings had recurrent sinopulmonary infections since childhood, responded to antibiotherapy well, neither of them had hospitalization history because of infections. One had chronic hepatitis B infection which may possibly be related to TAP1 gene defect.

PMID: 28161407 [PubMed – as supplied by publisher]

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