Research

Human mutations in methylenetetrahydrofolate dehydrogenase 1 impair nuclear de novo thymidylate biosynthesis.

May 1, 2015 By Manish Butte

Human mutations in methylenetetrahydrofolate dehydrogenase 1 impair nuclear de novo thymidylate biosynthesis.

Proc Natl Acad Sci U S A. 2015 Jan 13;112(2):400-5

Authors: Field MS, Kamynina E, Watkins D, Rosenblatt DS, Stover PJ

Abstract
An inborn error of metabolism associated with mutations in the human methylenetetrahydrofolate dehydrogenase 1 (MTHFD1) gene has been identified. The proband presented with SCID, megaloblastic anemia, and neurologic abnormalities, but the causal metabolic impairment is unknown. SCID has been associated with impaired purine nucleotide metabolism, whereas megaloblastic anemia has been associated with impaired de novo thymidylate (dTMP) biosynthesis. MTHFD1 functions to condense formate with tetrahydrofolate and serves as the primary entry point of single carbons into folate-dependent one-carbon metabolism in the cytosol. In this study, we examined the impact of MTHFD1 loss of function on folate-dependent purine, dTMP, and methionine biosynthesis in fibroblasts from the proband with MTHFD1 deficiency. The flux of formate incorporation into methionine and dTMP was decreased by 90% and 50%, respectively, whereas formate flux through de novo purine biosynthesis was unaffected. Patient fibroblasts exhibited enriched MTHFD1 in the nucleus, elevated uracil in DNA, lower rates of de novo dTMP synthesis, and increased salvage pathway dTMP biosynthesis relative to control fibroblasts. These results provide evidence that impaired nuclear de novo dTMP biosynthesis can lead to both megaloblastic anemia and SCID in MTHFD1 deficiency.

PMID: 25548164 [PubMed – indexed for MEDLINE]

Curative haploidentical BMT in a murine model of X-linked chronic granulomatous disease.

April 30, 2015 By Manish Butte

Curative haploidentical BMT in a murine model of X-linked chronic granulomatous disease.

Int J Hematol. 2015 Apr 29;

Authors: Takeuchi Y, Takeuchi E, Ishida T, Onodera M, Nakauchi H, Otsu M

Abstract
Chronic granulomatous disease (CGD) is a primary immunodeficiency disorder characterized by defective microbial killing in phagocytes. Long-term prognosis for CGD patients is generally poor, highlighting the need to develop minimally toxic, curative therapeutic approaches. We here describe the establishment of a mouse model in which X-linked CGD can be cured by allogeneic bone marrow transplantation. Using a combination of non-myeloablative-dose total body irradiation and a single injection of anti-CD40 ligand monoclonal antibody, transplantation of whole bone marrow cells achieved long-lasting mixed chimerism in X-linked CGD mice in a haploidentical transplantation setting. Stable mixed chimerism was maintained for up to 1 year even at a low range (<20 % donor cells), indicating induction of donor-specific tolerance. The regimen induced mild myelosuppression without severe acute complications. Stable chimerism was therapeutic, as it suppressed cutaneous granuloma formation in an in vivo test suited for evaluation of treatment efficacy in murine CGD models. These results warrant future development of a simplified allogeneic hematopoietic cell transplantation regimen that would benefit CGD patients by allowing the use of haploidentical donor grafts without serious concerns of severe treatment-related toxicity.

PMID: 25921405 [PubMed – as supplied by publisher]

Protein microarrays: a new tool for the study of autoantibodies in immunodeficiency.

April 24, 2015 By Manish Butte

Protein microarrays: a new tool for the study of autoantibodies in immunodeficiency.

Front Immunol. 2015;6:138

Authors: Rosenberg JM, Utz PJ

Abstract
Autoimmunity is highly coincident with immunodeficiency. In a small but growing number of primary immunodeficiencies, autoantibodies are diagnostic of a given disease and implicated in disease pathogenesis. In order to improve our understanding of the role of autoantibodies in immunodeficiencies and to discover novel autoantibodies, new proteomic tools are needed. Protein microarrays have the ability to screen for reactivity to hundreds to many thousands of unique autoantigens simultaneously on a single chip using minimal serum input. Here, we review different types of protein microarrays and how they can be useful in framing the study of primary and secondary immunodeficiencies.

PMID: 25904912 [PubMed]

Strategies for B-cell receptor repertoire analysis in primary immunodeficiencies: from severe combined immunodeficiency to common variable immunodeficiency.

April 24, 2015 By Manish Butte

Strategies for B-cell receptor repertoire analysis in primary immunodeficiencies: from severe combined immunodeficiency to common variable immunodeficiency.

Front Immunol. 2015;6:157

Authors: IJspeert H, Wentink M, van Zessen D, Driessen GJ, Dalm VA, van Hagen MP, Pico-Knijnenburg I, Simons EJ, van Dongen JJ, Stubbs AP, van der Burg M

Abstract
The antigen receptor repertoires of B- and T-cells form the basis of the adaptive immune response. The repertoires should be sufficiently diverse to recognize all possible pathogens. However, careful selection is needed to prevent responses to self or harmless antigens. Limited antigen receptor repertoire diversity leads to immunodeficiency, whereas unselected or misdirected repertoires can result in autoimmunity. The antigen receptor repertoire harbors information about abnormalities in many immunological disorders. Recent developments in next generation sequencing allow the analysis of the antigen receptor repertoire in much greater detail than ever before. Analyzing the antigen receptor repertoire in patients with mutations in genes responsible for the generation of the antigen receptor repertoire will give new insights into repertoire formation and selection. In this perspective, we describe strategies and considerations for analysis of the naive and antigen-selected B-cell repertoires in primary immunodeficiency patients with a focus on severe combined immunodeficiency and common variable immunodeficiency.

PMID: 25904919 [PubMed]

Mast cell interleukin-1 beta, neutrophil interleukin-17 and epidermal antimicrobial proteins in the neutrophilic urticarial dermatosis in Schnitzler's syndrome.

April 24, 2015 By Manish Butte

Mast cell interleukin-1 beta, neutrophil interleukin-17 and epidermal antimicrobial proteins in the neutrophilic urticarial dermatosis in Schnitzler’s syndrome.

Br J Dermatol. 2015 Apr 22;

Authors: de Koning HD, van Vlijmen-Willems IM, Rodijk-Olthuis D, van der Meer JW, Zeeuwen PL, Simon A, Schalkwijk J

Abstract
BACKGROUND: Schnitzler’s syndrome (SchS) is an autoinflammatory disease characterized by a chronic urticarial rash, a monoclonal component, and signs of systemic inflammation. Interleukin-1 beta (IL-1β) is pivotal in the pathophysiology.
OBJECTIVES: Here we investigated the cellular source of pro-inflammatory mediators in skin of SchS patients.
METHODS: Skin biopsies of lesional and non-lesional skin from eight SchS patients and healthy controls, cryopyrin-associated periodic syndrome (CAPS), delayed-pressure urticaria (DPU) and cold contact urticaria (CCU) patients were used. We studied in vivo IL-1β, IL-17 and antimicrobial protein (AMP) expression in resident skin cells and infiltrating cells. In addition we investigated the in vitro effect of IL-1β, IL-17 and poly:IC stimulation on cultured epidermal keratinocytes.
RESULTS: Remarkably, we found IL-1β-positive dermal mast cells both in lesional and non-lesional skin of SchS patients, but not in normal control skin, CCU, and fewer in CAPS. IL-17-positive neutrophils were only observed in lesional SchS and DPU skin. In lesional SchS epidermis, mRNA and protein expression levels of AMPs were strongly increased compared to non-lesional skin and that of healthy controls. When exposed to IL-1β, poly:IC, or IL-17, patient and control primary human keratinocytes produced AMPs in similar amounts.
CONCLUSIONS: To conclude, dermal mast cells of SchS patients produce IL-1β. This presumably leads to activation of keratinocytes and neutrophil influx, and further amplification of inflammation by IL-17 (from neutrophils and mast cells) and epidermal AMP production leading to chronic histamine-independent neutrophilic urticarial dermatosis. This article is protected by copyright. All rights reserved.

PMID: 25904179 [PubMed – as supplied by publisher]

Single-cell mass cytometry of TCR signaling: amplification of small initial differences results in low ERK activation in NOD mice.

April 24, 2015 By Manish Butte

Single-cell mass cytometry of TCR signaling: amplification of small initial differences results in low ERK activation in NOD mice.

Proc Natl Acad Sci U S A. 2014 Nov 18;111(46):16466-71

Authors: Mingueneau M, Krishnaswamy S, Spitzer MH, Bendall SC, Stone EL, Hedrick SM, Pe’er D, Mathis D, Nolan GP, Benoist C

Abstract
Signaling from the T-cell receptor (TCR) conditions T-cell differentiation and activation, requiring exquisite sensitivity and discrimination. Using mass cytometry, a high-dimensional technique that can probe multiple signaling nodes at the single-cell level, we interrogate TCR signaling dynamics in control C57BL/6 and autoimmunity-prone nonobese diabetic (NOD) mice, which show ineffective ERK activation after TCR triggering. By quantitating signals at multiple steps along the signaling cascade and parsing the phosphorylation level of each node as a function of its predecessors, we show that a small impairment in initial pCD3ζ activation resonates farther down the signaling cascade and results in larger defects in activation of the ERK1/2-S6 and IκBα modules. This nonlinear property of TCR signaling networks, which magnifies small initial differences during signal propagation, also applies in cells from B6 mice activated at different levels of intensity. Impairment in pCD3ζ and pSLP76 is not a feedback consequence of a primary deficiency in ERK activation because no proximal signaling defect was observed in Erk2 KO T cells. These defects, which were manifest at all stages of T-cell differentiation from early thymic pre-T cells to memory T cells, may condition the imbalanced immunoregulation and tolerance in NOD T cells. More generally, this amplification of small initial differences in signal intensity may explain how T cells discriminate between closely related ligands and adopt strongly delineated cell fates.

PMID: 25362052 [PubMed – indexed for MEDLINE]

Successful hematopoietic cell transplantation in a patient with X-linked agammaglobulinemia and acute myeloid leukemia.

April 23, 2015 By Manish Butte

Successful hematopoietic cell transplantation in a patient with X-linked agammaglobulinemia and acute myeloid leukemia.

Pediatr Blood Cancer. 2015 Apr 20;

Authors: Abu-Arja RF, Chernin LR, Abusin G, Auletta J, Cabral L, Egler R, Ochs HD, Torgerson TR, Lopez-Guisa J, Hostoffer RW, Tcheurekdjian H, Cooke KR

Abstract
X-linked agammaglobulinemia (XLA) is a primary immunodeficiency characterized by marked reduction in all classes of serum immunoglobulins and the near absence of mature CD19(+) B-cells. Although malignancy has been observed in patients with XLA, we present the first reported case of acute myeloid leukemia (AML) in a patient with XLA. We also demonstrate the complete correction of the XLA phenotype following allogeneic hematopoietic cell transplantation for treatment of the patient’s leukemia. Pediatr Blood Cancer © 2015 Wiley Periodicals, Inc.

PMID: 25900577 [PubMed – as supplied by publisher]

Immunoglobulin rearrangement analysis from multiple lesions in the same patient using Next Generation Sequencing.

April 22, 2015 By Manish Butte

Immunoglobulin rearrangement analysis from multiple lesions in the same patient using Next Generation Sequencing.

Histopathology. 2015 Apr 18;

Authors: Appenzeller S, Gilissen C, Rijntjes J, Tops BB, Kastner-van Raaij A, Hebeda KM, Nissen L, Dutilh BE, van Krieken JH, Groenen PJ

Abstract
BACKGROUND: For patients who have multiple lymphomas with discordant pathology, it is relevant to determine whether there is one disseminated lymphoma or two unrelated lymphomas. Patients with disseminated, clonally related lymphomas, are usually treated with the most powerful drugs available, while patients with unrelated (primary) lymphomas mostly receive standard first-line therapies.
METHODS: We have used next generation sequencing on the Ion Torrent Personal Genome Machine to characterize the immunoglobulin heavy gene V-D-J rearrangements in two diagnostic tissue samples, including formalin-fixed and paraffin-embedded tissue, of two patients with iatrogenic immunodeficiency-associated Epstein-Barr virus lymphoproliferative disorder, with ulcerative colitis as underlying disease.
RESULTS: The immunoglobulin rearrangement sequences obtained by next generation sequencing revealed undoubtedly clonally related lesions in two tissue biopsies that were taken over time in the first patient, which is concordant with disseminated lymphoma. The other patient showed two clonally unrelated lesions, which is incompatible with clonal dissemination. This information was not inferred from evaluation of the heavy and light chain rearrangements by fragment analysis, which is currently the gold standard.
CONCLUSION: Our study demonstrates the diagnostic application of next generation sequencing of immunoglobulin rearrangement assessment in pathology for clinical decision making in patients with several simultaneous or subsequent lymphoproliferations. This article is protected by copyright. All rights reserved.

PMID: 25891511 [PubMed – as supplied by publisher]

Evaluation of four comorbidity indices and Charlson comorbidity index adjustment for colorectal cancer patients.

April 22, 2015 By Manish Butte

Evaluation of four comorbidity indices and Charlson comorbidity index adjustment for colorectal cancer patients.

Int J Colorectal Dis. 2014 Sep;29(9):1159-69

Authors: Marventano S, Grosso G, Mistretta A, Bogusz-Czerniewicz M, Ferranti R, Nolfo F, Giorgianni G, Rametta S, Drago F, Basile F, Biondi A

Abstract
INTRODUCTION: Cancer survival is related not only to primary malignancy but also to concomitant nonmalignant diseases. The aim of this study was to investigate the prognostic capacity of four comorbidity indices [the Charlson comorbidity index (CCI), the Elixhauser method, the National Institute on Aging (NIA) and National Cancer Institute (NCI) comorbidity index, and the Adult Comorbidity Evaluation-27 (ACE-27)] for both cancer-related and all-cause mortality among colorectal cancer patients. A modified version of the CCI adapted for colorectal cancer patients was also built.
METHODS: The study population comprised 468 cases of colorectal cancer diagnosed between 1 January 2000 and 31 December 2010 at a community hospital. Data were prospectively collected and abstracted from patients’ clinical records. Kaplan-Meier method and multivariate logistic regression models were performed for survival and risk of death analysis.
RESULTS: Only moderate or severe renal disease [hazard ratio (HR) 2.71, 95% confidence interval (CI) 1.11-6.63] and AIDS (HR 3.27, 95% CI 1.23-8.68) were independently associated with cancer-specific mortality, with a population attributable risk of 5.18 and 4.36%, respectively. For each index, the highest comorbidity burden was significantly associated with poorer overall survival (NIA/NCI: HR 2.14, 95% CI 1.14-4.01; Elixhauser: HR 1.98, 95% CI 1.09-1.42; ACE-27: HR 1.78, 95% CI 1.07-1.23; CCI: HR 1.68, 95% CI 1.05-1.42) and cancer-specific survival. The modified version of the CCI resulted in a higher predictive power compared with other indices studied (cancer-specific mortality HR = 2.37, 95% CI 1.37-4.08).
CONCLUSIONS: The comorbidity assessment tools provided better prognostic prevision of prospective outcome of colorectal cancer patients than single comorbid conditions.

PMID: 25064390 [PubMed – indexed for MEDLINE]

Association of CLEC16A with human common variable immunodeficiency disorder and role in murine B cells.

April 22, 2015 By Manish Butte

Association of CLEC16A with human common variable immunodeficiency disorder and role in murine B cells.

Nat Commun. 2015;6:6804

Authors: Li J, Jørgensen SF, Maggadottir SM, Bakay M, Warnatz K, Glessner J, Pandey R, Salzer U, Schmidt RE, Perez E, Resnick E, Goldacker S, Buchta M, Witte T, Padyukov L, Videm V, Folseraas T, Atschekzei F, Elder JT, Nair RP, Winkelmann J, Gieger C, Nöthen MM, Büning C, Brand S, Sullivan KE, Orange JS, Fevang B, Schreiber S, Lieb W, Aukrust P, Chapel H, Cunningham-Rundles C, Franke A, Karlsen TH, Grimbacher B, Hakonarson H, Hammarström L, Ellinghaus E

Abstract
Common variable immunodeficiency disorder (CVID) is the most common symptomatic primary immunodeficiency in adults, characterized by B-cell abnormalities and inadequate antibody response. CVID patients have considerable autoimmune comorbidity and we therefore hypothesized that genetic susceptibility to CVID may overlap with autoimmune disorders. Here, in the largest genetic study performed in CVID to date, we compare 778 CVID cases with 10,999 controls across 123,127 single-nucleotide polymorphisms (SNPs) on the Immunochip. We identify the first non-HLA genome-wide significant risk locus at CLEC16A (rs17806056, P=2.0 × 10(-9)) and confirm the previously reported human leukocyte antigen (HLA) associations on chromosome 6p21 (rs1049225, P=4.8 × 10(-16)). Clec16a knockdown (KD) mice showed reduced number of B cells and elevated IgM levels compared with controls, suggesting that CLEC16A may be involved in immune regulatory pathways of relevance to CVID. In conclusion, the CLEC16A associations in CVID represent the first robust evidence of non-HLA associations in this immunodeficiency condition.

PMID: 25891430 [PubMed – in process]