Search

Objective: Chronic granulomatous disease (CGD) is characterized by increased susceptibility to infections and inflammation that may lead to various gastrointestinal (GI) abnormalities. Our objective was to better characterize the GI manifestations among patients suffering from CGD as well as the effects of different treatments.Methods: We analyzed 11 patients with CGD managed by the immunology service at the Hospital for Sick Children, Toronto, Ontario between 2000 and 2012.Results: All patients had one or more GI abnormality including colitis (72.7%), peri-anal fissure/abscess (36.3%) or oral aphthous ulcers (36.3%). Failure to thrive occurred in 5 patients (45.4%), all with associated colitis. Bone marrow transplantations (BMT) using HLA-identical sibling donors were performed in 4 patients, with 3 patients surviving. In these 3 patients, the inflammation-mediated GI manifestations present before BMT resolved during the follow-up period of 3.2-4.6 years. In contrast, 6 of 7 patients who did not receive BMT (p=0.033) continued to suffer from GI disease resulting in failure to thrive, GI bleeding and life threatening small bowel perforation and often required immune suppressive medications.Conclusions: Inflammatory GI manifestations, particularly colitis, are very common in CGD and are often associated with significant morbidity. Allogeneic BMT, particularly if an HLA-matched sibling donor is available should be considered in patients with CGD who suffer from significant GI involvement.

To review the recent advances in the understanding and management of the immune and nonimmune effects of inherited adenosine deaminase (ADA) and purine nucleoside phosphorylase (PNP) deficiencies.Abnormal thymocyte development and peripheral T-cell activation in ADA-deficient and PNP-deficient patients cause increased susceptibility to infections and immune dysregulation. The impaired purine homeostasis also damages many other cell types and tissues. Animal studies suggest that defects in surfactant metabolism by alveolar macrophages cause the pulmonary alveolar proteinosis commonly seen in ADA-deficient infants, while toxicity of purine metabolites to cerebellar Purkinje cells may lead to the ataxia frequently observed in PNP deficiency. Patients' outcome with current treatments including enzyme replacement and stem cell transplantations are inferior to those achieved in most severe immunodeficiency conditions. New strategies, including intracellular enzyme replacement, gene therapy and innovative protocols for stem cell transplantations hold great promise for improved outcomes in ADA and PNP deficiency. Moreover, newborn screening and early diagnosis will allow prompt application of these novel treatment strategies, further improving survival and reducing morbidity.Better understanding of the complex immune and nonimmune effects of ADA and PNP deficiency holds great promise for improved patients' outcome.

The field of primary immunodeficiency continues to expand. The rate of discovery of new genes associated with primary immunodeficiency, especially T-cell immunodeficiency, has been accelerating because of the growing application of exome and genome studies. In this chapter, we focus on conditions where cellular deficiency is the predominant component leading to immunodeficiency. Attention has been given to describing unusual clinical phenotypes as well as novel immunodeficiencies. Included are also multisystem syndromes that encompass significant T-cell immunodeficiency, condition-specific treatment options, and new diagnostic developments, such as screening of newborns for severe combined immunodeficiency (SCID).

Although the extreme condition of typical profound T-cell dysfunction (TD), severe combined immunodeficiency (SCID), has been carefully defined, we are currently in the process of better defining less typical T-cell deficiencies, which tend to present with autologous circulating T-cell combined immunodeficiency (CID). Because autologous cells might interfere with the outcome of bone marrow transplantation, protocols usually include conditioning regimens. Therefore it is important to define the numbers of autologous cells usually detected in patients with CID versus those with SCID.We sought to determine the number of circulating T cells in patients with SCID as opposed to those with CID, to study their function, and to evaluate their possible detection during newborn screening using T-cell receptor excision circle (TREC) analysis.Numbers of circulating CD3(+) T cells (as determined by means of flow cytometry), in vitro responses to PHA, and TREC levels, all measured at presentation, were compiled from the research charts of the entire cohort of patients followed prospectively for T-cell immunodeficiency at the Hospital for Sick Children. Clinical data were ascertained retrospectively from the patient's hospital charts.One hundred three patients had CD3(+) determinations, and 80 of them had a genetic diagnosis. All patients considered to have typical SCID had CD3(+) T-cell counts of fewer than 500 cells/μL. Some variability was observed among different genotypes. In vitro responses to PHA were recorded in 88 patients, of whom 68 had a genetic diagnosis. All patients with low CD3(+) T-cell numbers (500 cells/μL) also had markedly decreased responses to PHA (typical SCIDs). However, responses ranged widely in the groups of patients with TD who had more than 500 CD3(+) autologous circulating T cells per microliter. Although patients with Omenn syndrome and ζ chain-associated protein, 70 kDa (ZAP70), and purine nucleoside phosphorylase (PNP) deficiencies had low responses, patients with the p.R222C mutation in the IL-2 receptor γ(IL2RG) gene as well as IL-10 receptor and CD40 ligand deficiencies had normal or near-normal mitogen responses. Finally, 51 patients had TREC levels measured. All patients with typical SCID, Omenn syndrome, and ZAP70 deficiency had low TREC levels. In contrast, patients with mutations in forkhead box protein 3 (FOXP3), CD40 ligand (CD40L), and IL-10 receptor α(IL10RA), as well as patients with the p.R222C mutation in the IL2RG gene, had normal TREC levels.Patients with typical SCID can be defined as having fewer than 500 circulating CD3(+) T cells. Most patients with autologous T cells still have profound TD, as defined by reduced in vitro function and thymus output. Some patients with conditions including TD have normal TREC levels and will therefore not be detected in a TREC-based newborn screening program.

Inherited defects in purine nucleoside phosphorylase (PNP) cause severe T cell immunodeficiency and progressive neurological dysfunction, yet little is known about the effects of PNP deficiency on the brain. PNP-KO mice display metabolic and immune anomalies similar to those observed in patients. Our objectives were to characterize brain abnormalities in PNP-KO mice and determine whether restoring PNP activity prevents these abnormalities. We analyzed structural brain defects in PNP-KO mice by magnetic resonance imaging, while assessing motor deficits using the accelerating rotarod and stationary balance beam tests. We detected morphological abnormalities and apoptosis in the cerebellum of PNP-KO mice by hematoxylin and eosin, electron microscopy, TUNEL and activated caspase 3 staining. We treated PNP-KO mice with PNP fused to the HIV-TAT protein transduction domain (TAT-PNP) from birth or from 4 weeks of age. Magnetic resonance imaging revealed a smaller than normal cerebellum in PNP-KO mice. PNP-KO mice displayed motor abnormalities including rapid fall from the rotating rod and frequent slips from the balance beam. The cerebellum of PNP-KO mice contained reduced purkinje cells (PC), which were irregular in shape and had degenerated dendrites. PC from the cerebellum of PNP-KO mice, expanded ex vivo, demonstrated increased apoptosis, which could be corrected by supplementing cultures with TAT-PNP. TAT-PNP injections restored PNP activity in the cerebellum of PNP-KO mice. TAT-PNP from birth, but not treatment initiated at 4 weeks of age, prevented the cerebellar PC damage and motor deficits. We conclude that PNP deficiency cause cerebellar abnormalities, including PC damage and progressive motor deficits. TAT-PNP treatment from birth can prevent the neurological abnormalities in PNP-KO mice.

Background Inherited defects in the function of adenosine deaminase (ADA) cause severe combined immunodeficiency (SCID) and affect many other cells and tissues. Objectives We sought to characterize the frequency and features of pulmonary alveolar proteinosis (PAP) in patients with ADA deficiency. Methods Clinical and laboratory features of all patients with SCID caused by ADA deficiency in a single center were analyzed. Bronchoalveolar lavage (BAL) fluid and lung biopsy specimens were stained with hematoxylin and eosin and periodic acid–Schiff, visualized by means of electron microscopy, and studied for associated infections. As a control group, BAL fluid and biopsy specimens from 22 patients with SCID caused by other genetic abnormalities were similarly assessed. Results Among 16 consecutive patients with ADA deficiency, 7 had BAL fluid containing periodic acid–Schiff–positive surfactant-like material with macrophages engulfing degenerating lamellar bodies and/or lung biopsy specimens with alveolar spaces filled with homogeneous granular eosinophilic material and large macrophages. The lung pathology was typical of PAP. Identification of various pathogens coincided with PAP in 3 of these patients. We have diagnosed PAP among patients with ADA deficiency more commonly in the last 10 years than previously ( P = .05), likely reflecting increased awareness of this condition. There were no significant differences in the clinical or immunologic characteristics between patients with ADA deficiency with or without PAP. Similar findings of PAP were not found among patients with SCID caused by other genetic abnormalities ( P = .001). ADA coupled to polyethylene glycol or allogeneic hematopoietic stem cell transplantation rapidly corrected this pulmonary complication. PAP seems to have contributed to the death of only 1 patient with ADA deficiency. Conclusions ADA deficiency predisposes to the development of PAP, which could be reversed after enzyme replacement or transplantation.

Background. Hyperbaric oxygen (HBO) therapy, which is used for many conditions, may also have immunosuppressive effects and could be used for prevention or treatment of graft-versus-host disease (GvHD). If HBO is immunosuppressant, then we hypothesize that HBO therapy will delay the T-cell mediated skin graft rejection. Methods. C57/BL6 black-coated (H2B) mice received skin graft from CBA (H2D) white-coated mice. Mice were treated with either 19 session of 240 kpa oxygen or 29 session of 300 kpa oxygen, for 90 minutes. Mice were housed either 4 per cage or separately, to prevent friction and mechanical factors that may affect graft survival. Skin grafts were assessed daily. Results. There was no difference in length of graft survival between mice that received either regimens of HBO therapy and mice that did not receive HBO therapy. Conclusions. HBO therapy, as a sole agent, did not delay skin graft rejection in a highly immunogenic mouse model.

To measure resting energy expenditure (REE) and determine whether increased REE (hypermetabolism) is associated with failure to thrive (FTT) in patients with severe combined immunodeficiency (SCID) at diagnosis.REE was measured in 26 patients with SCID in a single transplant center. Predicted REE was determined with World Health Organization standards. Measured REE110% of predicted REE was classified as hypermetabolism. Other data collected included FTT status, infections, genotype, phenotype, and the feeding methods used.Fifteen of 26 patients (57.7%) had FTT, and 18 of 26 patients (69.2%) were hypermetabolic. Hypermetabolism occured in 14 of 15 patients (93%) with FTT, and only 4 of 11 patients (36%) without FTT had hypermetabolism (P = .003). There was a significant difference between the measured REE (71.75 ± 16.6 kcal/kg) and the predicted REE (52.85 ± 2.8 kcal/kg; P.0001). Eleven of 17 patients (65%) required nasogastric feeding, parenteral nutrition, or both to meet their energy needs.Hypermetabolism is common in patients with SCID and may contribute to the development of FTT. The hypermetabolism in these patients may necessitate intensive nutrition support.

Little information is currently available on the outcome and the long-term restoration of immune function in infants with Omenn syndrome (OS) treated with bone marrow transplantation (BMT). We prospectively followed patients with OS who received matched unrelated donor (MUD) BMT at our center. Engraftment, immune reconstitution, and transplant-related complications were recorded. Humoral and cellular immunity were evaluated. Six patients with OS were diagnosed at a mean age of 4.6 months and received a matched unrelated donor BMT as the first BMT at the mean age of 9.4 months. All six patients are alive and well at a mean 95 months after transplant. All patients have evidence of full hemopoetic engraftment and robust immune function. We have shown here that matched unrelated donor BMT is highly effective in curing patients with OS regardless of their genotype. This mode of treatment should be preferred for patients with OS when a related identical donor is not available.

Adenosine deaminase (ADA) deficiency is a disorder of the purine metabolism leading to combined immunodeficiency and systemic alterations, including skeletal abnormalities. We report that ADA deficiency in mice causes a specific bone phenotype characterized by alterations of structural properties and impaired mechanical competence. These alterations are the combined result of an imbalanced receptor activator of nuclear factor-κB ligand (RANKL)/osteoprotegerin axis, causing decreased osteoclastogenesis and an intrinsic defect of osteoblast function with subsequent low bone formation. In vitro, osteoblasts lacking ADA displayed an altered transcriptional profile and growth reduction. Furthermore, the bone marrow microenvironment of ADA-deficient mice showed a reduced capacity to support in vitro and in vivo hematopoiesis. Treatment of ADA-deficient neonatal mice with enzyme replacement therapy, bone marrow transplantation, or gene therapy resulted in full recovery of the altered bone parameters. Remarkably, untreated ADA–severe combined immunodeficiency patients showed a similar imbalance in RANKL/osteoprotegerin levels alongside severe growth retardation. Gene therapy with ADA-transduced hematopoietic stem cells increased serum RANKL levels and children's growth. Our results indicate that the ADA metabolism represents a crucial modulatory factor of bone cell activities and remodeling. The trials were registered at www.clinicaltrials.gov as #NCT00598481 and #NCT00599781.

Background Purine nucleoside phosphorylase (PNP) deficiency causes the accumulation of toxic purine metabolites and lethal T cell immune defects, which might be corrected by expressing PNP by transplanting bone marrow (BM) cells transduced with lentiviral vectors containing the human PNP gene (lentiPNP). Methods Lymphocytes from a single PNP-deficient patient as well as lymphocytes, fibroblasts and BM from PNP-deficient (PNP − /−) mice were transduced with lentiPNP. Female PNP − /− mice were transplanted with lentiPNP transduced BM cells from male PNP − /− mice or normal BM. Results LentiPNP transduction significantly increased PNP expression in PNP-deficient human lymphocytes, murine lymphocytes, fibroblasts and BM cells. LentiPNP transduction also significantly improved the proliferation of PNP − /− murine lymphocyte and survival of irradiated PNP − /− fibroblasts. Polymerase chain reaction analysis demonstrated efficient transduction of lentiPNP into total and lineage-depleted BM cells grown ex vivo. LentiPNP transduced PNP − /− BM cells transplanted into PNP − /− mice expressed PNP in vivo, partially restored urinary uric acid secretion, improved thymocytes maturation, increased weight gain and extended survival of the mice. However, 12 weeks after transplant, the benefit of lentiPNP transduced cells and normal BM diminished and the percentage of engrafted donor cells decreased. Conclusions This short-term observational study provides the first in vivo proof that gene therapy may correct some of the abnormalities associated with PNP deficiency. Better gene transduction and expression, as well as improved cell engraftment, are required to further advance PNP gene therapy. Copyright © 2008 John Wiley & Sons, Ltd.

We describe a patient with severe combined immunodeficiency because of aberrations in adenosine deaminase (ADA) who despite adequate replacement with polyethylene glycol-linked ADA (PEG-ADA) for 13 years developed Burkitt's lymphoma. Although treatment corrected the metabolic abnormalities caused by ADA deficiency, it failed to fully restore cellular immunity.

Purine nucleoside phosphorylase (PNP) is an intracellular enzyme crucial for purine degradation. PNP defects result in metabolic abnormalities and fatal T cell immunodeficiency. Protein transduction domains (PTD) transfer molecules across biological membranes. We hypothesized that fusion of PTD to PNP (PTD-PNP) would be an effective method for treating PNP deficiency. We find that PTD-PNP rapidly enters PNP-deficient lymphocytes and increases intracellular enzyme activity for 96 h. Similar to endogenous PNP, PTD-PNP is predominantly distributed in the cytoplasm. PTD-PNP improve viability and correct abnormal functions of PNP-deficient T lymphocytes including their response to stimulation and IL-2 secretion. Intracellular transduction protects PTD-PNP from antibody neutralization and from elimination, which may also provide significant in vivo therapeutic advantages to PNP. In conclusion, PTD fusion is an attractive method for extended PNP intracellular enzyme replacement therapy for PNP-deficient patients as well as for the intracellular delivery of other proteins.

Background: 22q11 deletion syndrome (22q11DS) is characterized by conotruncal cardiac defects and hypoplasia of parathyroid glands and thymus, which result in variable hypoparathyroidism (HPT) and immune deficiency. Methods: To study the course of HPT and the spectrum of other associated manifestations we evaluated all patients with 22q11DS, confirmed by fluorescence in situ hybridization, and HPT who were under follow-up at the Calcium-bone clinic, The Hospital for Sick Children, Toronto. Patients were clinically assessed and their hospital records were reviewed. Results: Eighteen patients were included. At follow-up assessment at median age of 7.3 years HPT was judged complete in 11 (61%) and partial in 7 patients (39%). Patients with complete HPT presented with hypocalcemia later (median age at diagnosis 2.4 vs. 0.0 years) and more often with a hypocalcemic seizure than patients with partial HPT (73 vs. 29%). The spectrum of other associated manifestations did not differ between the groups. Conclusions: HPT in patients with 22q11DS is often partial. Many of the patients present with a hypocalcemic seizure which is predictive of complete HPT. Patients with complete and partial HPT do not differ in respect to their other associated features. Patients with features of 22q11DS should be actively screened for hypocalcemia to prevent development of symptomatic hypocalcemia.

ContextBone marrow transplantation (BMT) using stem cells obtained from a family-related, HLA-identical donor (RID) is the optimal treatment for patients with severe combined immune deficiency (SCID). In the absence of an RID, HLA-mismatched related donors (MMRDs) are often used. However, compared with RIDs, use of MMRDs for BMT is associated with reduced survival and inferior long-term immune reconstitution. Use of HLA-matched unrelated donors (MUDs) represents another potential alternative for BMT.ObjectiveTo compare outcomes and immune reconstitution in a large cohort of patients with SCID who received RID, MUD, or MMRD BMT.Design, Setting, and PatientsRetrospective study of medical records from 94 infants diagnosed as having SCID who received BMT between 1990 and 2004 at 1 Canadian and 1 Italian pediatric referral center. Thirteen, 41, and 40 patients received RID, MUD, and MMRD BMT, respectively.Main Outcome MeasuresSurvival and graft failure, along with incidence of graft-vs-host disease, infections, and other complications; immune reconstitution was assessed in children who survived for more than 2 years after BMT.ResultsSurvival after RID BMT was highest. Twelve (92.3%) of 13 patients who received RID BMT, 33 (80.5%) of 41 who received MUD BMT, and 21 (52.5%) of 40 patients who received MMRD BMT survived. Compared with MMRD BMT, survival was significantly higher with RID (P = .008) or with MUD (P = .03). Graft failures and need for repeat BMT were more common in patients receiving MMRD BMT than in those who underwent MUD BMT. Long-term reconstitution of a full T-cell repertoire was achieved more frequently following MUD BMT (94.7%) than after MMRD BMT (61.1%) (P = .02). Acute graft-vs-host disease was documented in 73.1% of patients following MUD BMT but in only 45% after MMRD BMT (P = .009). Conversely, interstitial pneumonitis was observed more frequently after MMRD BMT (14 [35.0%] of 40) than after MUD BMT (3 [7.3%] of 41; P = .002).ConclusionOur study suggests that in the absence of a relative with identical HLA, MUD BMT may provide better engraftment, immune reconstitution, and survival for patients with SCID than MMRD BMT.

Objective. The recombination activating enzymes RAG1 and RAG2 are essential to the process of V(D)J rearrangement in B and T cells and thus to the development of normal immune function. Mutations in RAG1 or RAG2 can lead to a spectrum of disorders, ranging from typical B−T− severe combined immunodeficiency to Omenn's syndrome. We present a unique presentation of RAG1 deficiency.Patient. We report on a 6-month-old girl who presented with severe respiratory distress, which continued to progress despite antibiotic therapy but seemed to respond to treatment with corticosteroids. The patient exhibited no erythroderma or eosinophilia, and her lymphoid organs were not enlarged.Results. Investigation of the immune system showed normal numbers of CD3+ T cells, which expressed either CD4 or CD8. Subsequent analysis of the T-cell receptor demonstrated that nearly all CD3+ T cells were clonal; one clone expressed CD4, whereas the other expressed CD8. The extremely restricted T-cell repertoire and the lack of circulating B cells prompted analysis of the RAG1 gene, which revealed a novel homozygous thymine to cytosine substitution at nucleotide position 2686.Conclusions. This case underscores the importance of more extensive evaluation of the immune system even when widely available, standard, flow cytometric analysis shows normal numbers of T cells that express CD4 or CD8, especially in the absence of circulating B cells.

Purine nucleoside phosphorylase (PNP) deficiency results in severe immune dysfunction and early death from infections. Lymphopenia, reduced serum uric acid, and abnormal PNP enzymatic activity assist in the diagnosis of PNP‐deficient patients. Analysis of the gene encoding PNP in these patients reveals several recurring mutations. Identification of these hot‐spots for mutation may allow faster confirmation of the diagnosis in suspected cases. Other polymorphisms have recently been described (Yu, L., Kalla, K., Guthrie, E., Vidrine, A., Klimecki, W.T.; Genetic variation in genes associated with arsenic metabolism: glutathione S‐transferase omega 1‐1 and purine nucleoside phosphorylase polymorphisms in European and indigenous Americans. Environ. Health. Perspect. 2003, 111, 1421–1427).

Hemophagocytic lymphohistiocytosis is thought to occur as a primary (familial) form or secondary to infection or malignancy. Recently, several defects in genes important for immune functions were identified in patients with HLH. These include mutations in perforin, the gamma common chain of the receptor for interleukin-2, Slap and purine nucleoside phosphorylase. Since abnormal function of these genes is associated with a wide clinical spectrum, HLH is probably another manifestation of immune deficiency and a thorough immune evaluation should be done in all such patients.

Editor—Spondyloepiphyseal dysplasia (SED) is a rare osteochondroplasia, characterised by disproportionate short stature with a short neck and trunk and barrel chest. The pelvis tends to be narrow and deep, the femoral neck short, and the femoral head flattened. Mild to moderate epiphyseal dysplasia of the large joints may also be seen. The latter may lead to premature secondary osteoarthritis with significant morbidity.1 SED may occur sporadically; however, in many cases the family history indicates an inherited condition. In some of these pedigrees, the inheritance pattern seems autosomal dominant, while in others it is consistent with autosomal recessive or X linked recessive.2 Recently, mutations in the gene designated SEDL , located on Xp22, were identified as the cause of X linked spondyloephiphyseal dysplasia tarda in three families.3 We have previously described a large kindred of British descent spanning four generations affected by SED.1 Briefly, 14 males between the ages of 10 and 77 years were affected, with early adolescence development of progressive decline in growth rate accompanied by short stature, short trunk, and barrel chest. Although some of them had to limit their activities because of hip or back limitation of movement or pain, many continued with normal activity and were …

In conclusion, multiple receptors and signal transduction cascades influence T-cell function and fate. During the past few years many of these important aspects of T-cell biology were identified. The complexity of the various signaling pathways has made appreciation of their clinical significance difficult. One way of studying the function of these molecules is to create mice deficient of these components. However, frequently the murine phenotype is far from reflecting the homologous human deficiency. It is therefore beneficial to define the human immunodeficiencies in order to understand the role of a certain signaling molecule in humans. Further, mutations that result in partial deficiencies may result in a different phenotype from null mutations. This information may aid in improving structure/function analysis of these signaling components.

Rationale: Purine nucleoside phsophorylase (PNP) is a cytoplasmic enzyme that is important in purine degradation and salvage pathways. PNP deficiency results in severe immune dysfunction accompanied often with systemic and neurological abnormalities. Currently there is no effective treatment for PNP deficiency. Several methods to correct this disorder are being evaluated including gene transfer and the use of protein transduction domains (PTD). PTD are short peptides that transport molecules across cell membranes. The ability to replace a missing intracellular enzyme by exogenous attachment to PTD and frequent administration of the fusion protein has not been determined.

In various autoimmune diseases it appears that NK activity is impaired, and that this phenomenon is significant in disease development. Impairment of NK activity may be the result of two different mechanisms. In systemic autoimmune diseases, in which various target organs are involved (nonorgan-specific), the peripheral blood NK level is generally lower than normal. This most likely allows the expression of autoimmune phenomena such as B cell hyperactivity and polyclonal antibody production, as is seen in SLE, due to a defect in the termination of the immune response. In autoimmune diseases with more localized, organ-specific lesions one can detect increased NK activity at the target organ itself. In these instances, the cytotoxic characteristic of the NK cell is more prominent. This theory explains why both increased and decreased NK activity may be observed in autoimmune diseases. In some disorders in which decreased NK activity was suspected of being crucial, immunomodulators, known to increase NK activity, were administered. Yet it is still difficult to separate the NK activity from the effect of the remaining immune system.

A1 Role of fibrocytes in allergic rhinitis Marie-Ève Côté, Marie-Ève Boulay, Sophie Plante, Jamila Chakir, Louis-Philippe Boulet A2 Patterns of aeroallergens sensitization in Northern Alberta Hanan Ahmed, Maria-Beatriz Ospina, Kyriaki Sideri, Harissios Vliagoftis A3 Addressing acceptable risk for adolescents with Food-Induced Anaphylaxis (FIA) Sara F. Johnson, Roberta L. Woodgate A4 Outcomes of matched related and unrelated bone marrow transplantation after reduced-toxicity conditioning for children suffering from Chronic Granulomatous Disease Guilhem Cros, Pierre Teira, Sonia Cellot, Henrique Bittencourt, Helene Decaluwe, Marie France Vachon, Michel Duval, Elie Haddad A5 Outcomes of patients with severe combined immunodeficiency (SCID) prior to and after initiation of newborn screening for SCID in Ontario Vy H.D. Kim, Anne Pham-Huy, Eyal Grunebaum A6 Detection of regulatory B cells in the airways of subjects with asthma John-Paul Oliveria, Stephanie Phan, Mark W. Tenn, Damian Tworek, Steven G. Smith, Adrian J. Baatjes, Caitlin D. Obminski, Caroline E. Munoz, Tara X. Scime, Roma Sehmi, Gail M Gauvreau A7 Characterization of IgE-expressing B cells in the airways and peripheral blood of allergic asthmatic subjects John-Paul Oliveria, Stephanie Phan, Mark W. Tenn, Brittany M Salter, Steven G Smith, Caitlin D Obminski, Caroline E Munoz, Abbey Schlatman, Tara X Scime, Rick Watson, Roma Sehmi, Gail M Gauvreau A8 Pregnancy: could it be a risk factor for primary immunodeficient patients Roya Sherkat, Razieh Khoshnevisan, Saba Sheikhbahaei A9 Clinical experience with Octagam: a Canadian retrospective chart review Stephen Betschel, Richard Warrington, Robert Schellenberg A10 Kounis syndrome secondary to contrast media with inferior ST elevations and bilateral ischemic stroke Michael N Fein, Jean-Philippe Pelletier A11 Honey bee venom immunotherapy ineffective in bumble bee-induced anaphylaxis: case report and review of literature Manstein Kan, Robert Schellenberg A12 Delayed immune reconstitution occurring after multiple immune complications of hematological stem cell transplantation for a leaky SCID Roxane Labrosse, Guilhem Cros, Pierre Teira, Henrique Bittencourt, Helene Decaluwe, Michel Duval, Elie Haddad A13 Comparison of Three Case Reports of Acquired Angioedema: presentation, management and outcome Raymond Mak, James Loh, Amin Kanani A14 Sitagliptin-associated angioedema not related to concurrent use of ARB or ACE inhibitor Dominik A. Nowak, Paul K. Keith A15 Sneddon-Wilkinson subcorneal pustular dermatosis associated with an IgA monoclonal gammopathy Daniel Pannozzo, Dominik A. Nowak, Hermenio C. Lima A16 Omalizumab can be effective in patients with allergic bronchopulmonary aspergillosis Diana Pham, Hoang Pham, Gonzalo G. Alvarez, Istvan T. Bencze, Krishna B. Sharma, Mark Smith, Shawn Aaron, Jennifer Block, Tara Keays, Judith Leech, David Schneidermen, Jodi Cameron, Jennifer Forgie, Alicia Ring, John W. O’Quinn, Stephanie Santucci, William H. Yang A17 Efficacious use of omalizumab in the treatment of cystic fibrosis Diana Pham, Hoang Pham, Ena Gaudet, Shawn Aaron, Stephanie Santucci, William H. Yang A18 HAE with normal C1-INH with inconsistent response to C1 esterase inhibitor infusion but reliably responsive to icatibant Hoang Pham, Stephanie Santucci, William H. Yang A19 Anaphylaxis reaction to lactase enzyme Mathew R. Voisin, Rozita Borici-Mazi A20 Risk of solid tumor malignancies in patients with primary immune deficiency Kateryna Vostretsova, Donald F. Stark A21 Is it time to adopt the chromogenic assay for measuring C1 esterase inhibitor function in patients with HAE Type 2? Elizabeth Yeboah, Paul K. Keith A22 Emergency department visits for anaphylaxis and allergic reactions Michelle Martin-Rhee, Cheryl Gula, Clare Cheng, Geoff Paltser A23 START: Susceptibility To food Allergies in a Registry of Twins Alizée Dery, Ann Clarke, Kari Nadeau, Laurie Harada, Kimberley Weatherall, Celia Greenwood, Denise Daley, Yuka Asai, Moshe Ben-Shoshan A24 Qualifying the diagnostic approach employed by allergists when managing patients with self-diagnosed non-celiac gluten sensitivity (NCGS) Lee Horgan, Teresa Pun A25 Retrospective analysis on the agreement between skin prick test and serum food specific IgE antibody in adults with suspected food allergy Ling Ling, Maria B. Ospina, Kyriaki Sideri, Harissios Vliagoftis A26 Staple food hypersensitivity from infancy to adolescence: a report from the BAMSE cohort Jennifer L.P. Protudjer, Mirja Vetander, Marianne van Hage, Ola Olén, Magnus Wickman, Anna Bergström A27 Evaluating the impact of supervised epinephrine autoinjector administration during food challenges on perceived parent confidence Timothy Teoh, Christopher Mill, Tiffany Wong, Ingrid Baerg, Angela Alexander, Kyla J. Hildebrand, John Dean, Boris Kuzeljevic, Edmond S. Chan A28 Local immunoglobulin production to Aspergillus fumigatus cystic fibrosis Jonathan Argeny, Mia Gona-Hoepler, Petra Fucik, Edith Nachbaur, Saskia Gruber, Reto Crameri, Andreas Glaser, Zsolt Szépfalusi, Claudio Rhyner, Thomas Eiwegger A29 Extract consumption with skin prick test (SPT) devices Greg. Plunkett, Brad Mire A30 Evaluation of our cases with nonsteroidal anti-inflammatory drug reactions Mehtap Yazicioglu, Ceren Can, Gokce Ciplak A31 Reasons for referral and final diagnoses in a tertiary care pediatric allergy clinic Victoria E. Cook, Kyla J. Hildebrand, Elodie Portales-Casamar, Christopher Mill, Edmond S. Chan A32 Internist referral practices for inpatients with self-reported penicillin allergies at a tertiary care teaching hospital Michael N Fein, Emil P Nashi A33 Assessing the risk of reactions in children with a negative oral challenge after a subsequent use of amoxicillin Sofianne Gabrielli, Christopher Mill, Marie-Noel Primeau, Christine Lejtenyi, Elena Netchiporouk, Alizee Dery, Greg Shand, Moshe Ben-Shoshan A34 Validity of self-reported penicillin allergies Erica Hoe, Joel Liem A35 Effectiveness of allergy-test directed elimination diets in eosinophilic esophagitis Jason K. Ko, David J.T. Huang, Jorge A. Mazza A36 Allergy testing and dietary management in pediatric eosinophilic esophagitis (EoE): A retrospective review of a tertiary Canadian centre’s experience Mary McHenry, Anthony Otley,Wade Watson A37 Visualizing the impact of atopic and allergic skin disease Dominik A. Nowak, John N. Kraft A38 Cystic fibrosis with and without nasal polyposis in pediatric patients: a cross-sectional comparative study Mihaela Paina, Ahmed A. Darwish Hassan, Delia Heroux, Lynn Crawford, Gail Gauvreau, Judah Denburg, Linda Pedder, Paul K. Keith A39 Evaluation of macrolide antibiotic hypersensitivity: the role of oral challenges in children Bahar Torabi, Marie-Noel Primeau, Christine Lejtenyi, Elaine Medoff, Jennifer Mill, Moshe Ben-Shoshan A40 Venom allergy testing: is a graded approach necessary? Jaclyn A. Quirt, Xia Wen, Jonathan Kim, Angel Jimenez Herrero, Harold L. Kim A41 The role of oral challenges in evaluating cephalosporin hypersensitivity reactions in children Magdalena J. Grzyb, Marie-Noël Primeau, Christine Lejtenyi, Elaine Medoff, Jennifer Mill, Moshe Ben-Shoshan A42 Breastfeeding and infant wheeze, atopy and atopic dermatitis: findings from the Canadian Healthy Infant Longitudinal Development Study Meghan B. Azad, Zihang Lu, Allan B. Becker, Padmaja Subbarao, Piushkumar J. Mandhane, Stuart E. Turvey, Malcolm R. Sears, the CHILD Study Investigators A43 IL33 DNA methylation in bronchial epithelial cells is associated to asthma Anne-Marie Boucher-Lafleur, Valérie Gagné-Ouellet, Éric Jacques, Sophie Plante, Jamila Chakir, Catherine Laprise A44 NRF2 mediates the antioxidant response to organic dust-induced oxidative stress in bronchial epithelial cells Michael Chen, Toby McGovern, Mikael Adner, James G. Martin A45 The effects of perinatal distress, immune biomarkers and mother-infant interaction quality on childhood atopic dermatitis (rash) at 18 months Nela Cosic, Henry Ntanda, Gerald Giesbrecht, Anita Kozyrskyj, Nicole Letourneau A46 Examining the immunological mechanisms associated with cow’s milk allergy Bassel Dawod, Jean Marshall A47 Tryptase levels in children presenting with anaphylaxis to the Montréal Children’s Hospital Sarah De Schryver, Michelle Halbrich, Ann Clarke, Sebastian La Vieille, Harley Eisman, Reza Alizadehfar, Lawrence Joseph, Judy Morris, Moshe Ben-Shoshan A48 Secondhand tobacco smoke exposure in infancy and the development of food hypersensitivity from childhood to adolescence Laura Y. Feldman, Jesse D. Thacher, Inger Kull, Erik Melén, Göran Pershagen, Magnus Wickman, Jennifer L. P. Protudjer, Anna Bergström A49 Combined exposure to diesel exhaust and allergen enhances allergic inflammation in the bronchial submucosa of atopic subjects Ali Hosseini, Tillie L. Hackett, Jeremy Hirota, Kelly McNagny, Susan Wilson, Chris Carlsten A50 Comparison of skin-prick test measurements by an automated system against the manual method Saiful Huq, Rishma Chooniedass, Brenda Gerwing, Henry Huang, Diana Lefebvre, Allan Becker A51 The accurate identification and quantification of urinary biomarkers of asthma and COPD through the use of novel DIL- LC-MS/MS methods Mona M. Khamis, Hanan Awad, Kevin Allen, Darryl J. Adamko, Anas El-Aneed A52 Systemic immune pathways associated with the mechanism of Cat-Synthetic Peptide Immuno-Regulatory Epitopes, a novel immunotherapy, in whole blood of cat-allergic people Young Woong Kim, Daniel R. Gliddon, Casey P. Shannon, Amrit Singh, Pascal L. C. Hickey, Anne K. Ellis, Helen Neighbour, Mark Larche, Scott J. Tebbutt A53 Reducing the health disparities: online support for children with asthma and allergies from low-income families Erika Ladouceur, Miriam Stewart, Josh Evans, Jeff Masuda, Nicole Letourneau, Teresa To, Malcolm King A54 Epigenetic association of PSORS1C1 and asthma in the Saguenay-Lac-Saint-Jean asthma study Miriam Larouche, Liming Liang, Catherine Laprise A55 IL-33 induces cytokine and chemokine production in human mast cells Stephanie A. Legere, Ian D. Haidl, Jean-Francois Legaré, Jean S. Marshall A56 Reference ranges for lung clearance index from infancy to adolescence for Canadian population Zihang Lu, Malcolm Sears, Theo J. Moraes, Felix Ratjen, Per Gustafsson, Wendy Lou, Padmaja Subbarao A57 Kingston Allergy Birth Cohort: cohort profile and mother/child characteristics to age 2 Michelle L. North, Elizabeth Lee, Vanessa Omana, Jenny Thiele, Jeff Brook, Anne K. Ellis A58 Cow’s milk protein specific IgE, IgA and IgG4 as a predictor of outcome in oral immunotherapy Tanvir Rahman, Duncan Lejtenyi, Sarah De Schryver, Ryan Fiter, Ciriaco Piccirillo, Moshe Ben-Shoshan, Bruce Mazer A59 Age of peanut introduction and development of reactions and sensitization to peanut Elinor Simons, Allan B. Becker, Rishma Chooniedass, Kyla Hildebrand, Edmond S. Chan, Stuart Turvey, Padmaja Subbarao, Malcolm Sears A60 Multi-omic blood biomarker signatures of the late phase asthmatic response Amrit Singh, Casey P. Shannon, Young Woong Kim, Mari DeMarco, Kim-Anh Le Cao, Gail M. Gauvreau, J. Mark FitzGerald, Louis-Philippe Boulet, Paul M. O’Byrne, Scott J. Tebbutt A61 Early life gut microbial alterations in children diagnosed with asthma by three years of age Leah T. Stiemsma, Marie-Claire Arrieta, Jasmine Cheng, Pedro A. Dimitriu, Lisa Thorson, Sophie Yurist, Boris Kuzeljevic, Diana L. Lefebvre, Padmaja Subbarao, Piush Mandhane, Allan Becker, Malcolm R. Sears, Kelly M. McNagny, Tobias Kollmann, the CHILD Study Investigators, William W. Mohn, B. Brett Finlay, Stuart E. Turvey A62 The relationship between food sensitization and atopic dermatitis at age 1 year in a Canadian birth cohort Maxwell M. Tran, Diana L. Lefebvre, Chinthanie F. Ramasundarahettige, Allan B. Becker, Wei Hao Dai, Padmaja Subbarao, Piush J. Mandhane, Stuart E. Turvey, Malcolm R. Sears A63 Allergen inhalation enhances Toll-like receptor-induced thymic stromal lymphopoietin receptor expression by hematopoietic progenitor cells in mild asthmatics Damian Tworek, Delia Heroux, Seamus N. O’Byrne, Paul M. O’Byrne, Judah A. Denburg A64 The Allergic Rhinitis Clinical Investigator Collaborative – replicated eosinophilia on repeated cumulative allergen challenges in nasal lavage samples Laura Walsh, Mena Soliman, Jenny Thiele, Lisa M. Steacy, Daniel E. Adams, Anne K. Ellis A65 The CHILD Study: optimizing subject retention in pediatric longitudinal cohort research Linda Warner, Mary Ann Mauro, Robby Mamonluk, Stuart E. Turvey A66 Differential expression of C3a and C5a in allergic asthma ChenXi Yang, Amrit Singh, Casey P. Shannon, Young Woong Kim, Ed M. Conway, Scott J. Tebbutt

The use of gene therapy (GT) for the treatment of primary immune deficiencies (PID) including severe combined immune deficiency (SCID) has progressed significantly in the recent years. In particular, long-term studies have shown that adenosine deaminase (ADA) gene delivery into ADA-deficient hematopoietic stem cells that are then transplanted into the patients corrects the abnormal function of the ADA enzyme, which leads to immune reconstitution. In contrast, the outcome was disappointing for patients with X-linked SCID, Wiskott–Aldrich syndrome and chronic granulomatous disease who received GT followed by autologous gene corrected transplantations, as many developed hematological malignancies. The malignancies were attributed to the predilection of the viruses used for gene delivery to integrated at oncogenic areas. The availability of safer and more efficient self-inactivating lentiviruses for gene delivery has reignited the interest in GT for many PID that are now in various stages of pre-clinical studies and clinical trials. Moreover, advances in early diagnosis of PID and gene editing technology coupled with enhanced abilities to generate and manipulate stem cells ex vivo are expected to further contribute to the benefit of GT for PID. Here we review the past, the present and the future of GT for PID, with particular emphasis on the Canadian perspective.

s / Biol Blood Marrow Transplant 21 (2015) S266eS321 S274 The identification of a donor has always limited the extent of allo HSCT. Recently it has been shown that a haploidentical donor could be a valid option to perform allo HSCT given adapted immunosuppression is used. Notably the use of PT-HDCy, after T-replete HSCT following reduced intensity (RIC) or non-myeloablative (NMAC) conditioning, has been associated with promising results. However little data exist concerning elderly population when this population is characterized by a lack of HLA matched sibling and a higher incidence of severe GVHD and non-relapse mortality. Using this strategy we transplanted 31 patients over the age of 55 years between 2010 and 2014 and compare their outcome with patients of the same age transplanted in the same period from a MRD or UD. 70% of the patients in haplo group were prepared with Flu-TBI 2gy (NMAC) (30% received Fludarabine-Busilvex based regimen without ATG) while all patients in other groups received the same RIC (Fludarabine (150 mg/m2) Busilvex (2 days) rabbit ATG (2 days)). Patients in haplo group received post graft immunosuppression with PTHDCy (50 mg/kg on D 3 and 4) followed with CSA and MMF while patients in other groups received either CSA starting on D1. Patients in the haplo group have a trend presenting higher comorbidities and more severe diseases (Table). A single graft failure related to donor anti-HLA antibodies were noted in haplo group. Median time to 0.5x109 ANC and 20x109platelets were respectively 21 (14-32) and 28 (14-52) days after haplo HSCT. Haplo and MRD HSCT patients presented with a similar NRM lower than UD patients while Haplo patients present a relapse rate intermediate between MRD and UD (table). Overall outcome after haplo do not differ from MRD transplant. There is a trend for better PFS after Haplo HSCT as compared with UD transplant (62% vs.41%; P1⁄40,14) (Figure 1). Progression-free and severe cGVHD-free survival was significantly better after haplo HSCT (62% vs. 35%; p1⁄40.03) (Figure 2). We conclude that T-replete Haplo HSCT after RIC and followed by PT-HDCy is associated with promising results notably as compared with UD HSCT. The low rate of severe aGVHD and cGVHD are likely to conduct to lower complications and better quality of life. The reduction of donor search duration and the absence of graft acquisition fees represent potential additional benefits. In this perspective, the place of Haplo HSCT in older patients should now be prospectively addressed.