The International Collaboration in Asthma, Allergy and Immunology initiated an international coalition among the American Academy of Allergy, Asthma & Immunology; the European Academy of Allergy and Clinical Immunology; the World Allergy Organization; and the American College of Allergy, Asthma & Immunology on common variable immunodeficiency. An author group was formed and then divided into individual committees. Within the committee, teams of authors were subgrouped to generate content for specific sections of the document. Content was derived from literature searches, relevant published guidelines, and clinical experience. After a draft of the document was assembled, it was collectively reviewed and revised by the authors. Where evidence was lacking or conflicting, the information presented represents the consensus expert opinion of the group. The full document was then independently reviewed by 5 international experts in the field, none of whom was among the authors of the original. The comments of these reviewers were incorporated before submission for publication.

Background The genetic etiologies of the hyper-IgE syndromes are diverse. Approximately 60-70% of patients with hyper-IgE syndrome have dominant mutations in STAT3, and a single patient was reported to have a homozygous TYK2 mutation. In the remaining hyper-IgE syndrome patients, the genetic etiology has not yet been identified. Methods We performed genome-wide single nucleotide polymorphism analysis for nine subjects with autosomal recessive hyper-IgE syndrome to locate copy number variations and homozygous haplotypes. Homozygosity mapping was performed with twelve subjects from seven additional families. The candidate gene was analyzed by genomic and cDNA sequencing to identify causative alleles in a total of 27 patients with autosomal recessive hyper-IgE syndrome. Findings Subtelomeric microdeletions were identified in six subjects at the terminus of chromosome 9p. In all patients the deleted interval involved DOCK8, encoding a protein implicated in the regulation of the actin cytoskeleton. Sequencing of subjects without large deletions revealed 16 patients from nine unrelated families with distinct homozygous mutations in DOCK8 causing premature termination, frameshift, splice site disruption, single exon- and micro-deletions. DOCK8 deficiency was associated with impaired activation of CD4+ and CD8+ T cells. Interpretation Autosomal recessive mutations in DOCK8 are responsible for many, though not all, cases of autosomal recessive hyper-IgE syndrome. DOCK8 disruption is associated with a phenotype of severe cellular immunodeficiency characterized by susceptibility to viral infections, atopic eczema, defective T cell activation and TH17 cell differentiation; and impaired eosinophil homeostasis and dysregulation of IgE.

Lucas et al. identify humans with a gain-of-function mutation in PIK3R1, encoding the p85α subunit of PI3K. The splice site mutation causes in-frame skipping of exon 11, resulting in altered p85α association with p110δ that stabilizes the catalytic subunit but fails to properly inhibit catalytic activity. The patients have immunodeficiency and lymphoproliferation with skewing of CD8+ T cells toward terminally differentiated and senescent effector cells that have shortened telomeres.

DOCK8 and MyD88 have been implicated in serologic memory. Here we report antibody responses were impaired and CD27+ memory B cells were severely reduced in DOCK8-deficient patients. Toll-like receptor 9 (TLR9)- but not CD40-driven B cell proliferation and immunoglobulin production were severely reduced in DOCK8-deficient B cells. In contrast, TLR9-driven expression of AICDA, CD23 and CD86, and activation of NF-κB, p38 and Rac1 were intact. DOCK8 associated constitutively with MyD88 and the tyrosine kinase Pyk2 in normal B cells. Following TLR9 ligation, DOCK8 became tyrosine phosphorylated by Pyk2, bound the Src family kinase Lyn and linked TLR9 to a Src-Syk-STAT3 cascade essential for TLR9-driven B cell proliferation and differentiation. Thus, DOCK8 functions as an adaptor in a TLR9-MyD88 signaling pathway in B cells.

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SummaryBackground In children, the clinical efficacy and immunological mechanisms of sublingual immunotherapy (SLIT) compared with subcutaneous immunotherapy (SCIT) is still to be elucidated. Objectives To compare SLIT, SCIT and pharmacotherapy in relation to clinical efficacy and immunological mechanisms that govern its effect in asthmatic/rhinitis children who were sensitized to house dust mite (HDM). Methods In this single centre, prospective, randomized, controlled, open labelled, three parallel group trial, 48 patients mono-sensitized to HDM were randomized to receive either SLIT (n = 16), SCIT (n = 16) or pharmacotherapy alone (n = 16). Symptom, medication and visual analogue score (VAS) were collected and bronchial-nasal hyper-reactivity, skin prick tests, total-specific IgE were performed at baseline and 12 months after treatment. In addition, peripheral blood mononuclear cells were cultured with recombinant Der p 1 and Bet v 1 extracts and allergen-specific IL-4, IL-5, IL-13, IFN-g, IL-10, and TGF-b secretions were measured. Results SLIT and SCIT demonstrated a significant reduction of total rhinitis and asthma symptom score, total medication score, VAS and skin reactivity to HDM (Po0.05) when compared with pharmacotherapy. A significant reduction of serum-specific HDM-IgE in SCIT and SLIT were observed. Moreover, titrated nasal provocative dose significantly increased in both immunotherapy groups when compared with the pharmacotherapy group. No adverse effects were reported in SLIT, while two patients demonstrated serious adverse events in SCIT. After 1 year of treatment, Der p 1-driven IL-10 significantly increased in SLIT compared with pharmacotherapy, whereas Bet v 1-driven TGF-b (negative control) increased significantly in SLIT only. No changes were observed for Th1-Th2 cytokines.Conclusion Both SLIT and SCIT demonstrated clinical improvement compared with pharmacotherapy in asthma/rhinitis children sensitized to HDM.

To evaluate the efficacy of specific sublingual immunotherapy (SLIT), we enrolled 15 children with asthma and rhinitis (7 girls, 8 boys, mean +/- SD age of 11.7 +/- 3.3) allergic to house dust mite (HDM) into a double-blind, placebo-controlled study. After a run-in period, patients were randomized to receive either placebo (n = 7) or SLIT (n = 8) with a standardized Dermatophagoides pteronyssinus (D. pteronyssinus) + Dermatophagoides farinea (D. farinea) 50/50 extract. They received increasing doses up to 100 index units of reactivity (IR) every day for 4 weeks, then 100 IR/day for another 4 weeks, followed by maintenance therapy consisting of 20 drops 2 times a week for 4 months. Efficacy was assessed at the end of 6 months of therapy according to symptom and medication scores, serum total IgE levels, results of lung function tests, methacholine provocation tests, and skin prick tests. Daily means for the asthma score and use of inhaled beta-2-mimetics decreased significantly in the SLIT group (P = 0.05, P = 0.028, respectively), whereas no such difference was observed in the placebo group. At the end of follow-up, mean daily doses of intranasal steroids needed for control of rhinitis symptoms decreased significantly in the SLIT group (P = 0.04). Baseline skin sensitivity to D. pteronyssinus and D. farinea was not significantly different between in the two groups, whereas end-point wheal diameter obtained with D. pteronyssinus extract was significantly less in the SLIT vs. the placebo group (P = 0.026). At the end of 6 months, peak expiratory flow (PEF) values in the placebo group was significantly lower than in the SLIT group (P = 0.049). Throughout the treatment period, the SLIT group was found to have less asthma exacerbations than the placebo group (P = 0.007). The provocation concentration causing a 20% drop in forced expired volume in 1 sec did not change throughout the treatment period in either groups. None of the patients reported local or systemic side effects from SLIT. Results of this study suggests that SLIT may be a useful alternative or additional therapy in the treatment of children with asthma/rhinitis due to HDM.

Both SCIT groups fared better than pharmacotherapy alone at the end of 1 year. Although the clinical and immunologic outcomes were mostly similar between the two IT groups, some favorable outcomes of vitamin D warrant further investigation in more selected populations with varying doses as adjunct to IT.