Novel genetic risk variants for pediatric celiac disease

Background: Celiac disease is a complex chronic immune-mediated disorder of the small intestine. Today, the pathobiology of the disease is unclear, perplexing differential diagnosis, patient stratification, and decision-making in the clinic. Methods: Herein, we adopted a next-generation sequencing approach in a celiac disease trio of Greek descent to identify all genomic variants with the potential of celiac disease predisposition. Results: Analysis revealed six genomic variants of prime interest: SLC9A4 c.1919G gt A, KIAA1109 c.2933T gt C and c. 4268_4269delCCinsTA, HoxB6 c.668C gt A, HoxD12 c.418G gt A, and NCK2 c.745_746delAAinsG, from which NCK2 c.745_746delAAinsG is novel. Data validation in pediatric celiac disease patients of Greek (n=109) and Serbian (n=73) descent and their healthy counterparts (n=111 and n=32, respectively) indicated that HoxD12 c.418G gt A is more prevalent in celiac disease patients in the Serbian population (P lt 0.01), while NCK2 c.745_746delAAinsG is less prevalent in celiac disease patients rather than healthy individuals of Greek descent (P = 0. 03). SLC9A4 c.1919G gt A and KIAA1109 c.2933T gt C and c.4268_4269delCCinsTA were more abundant in patients; nevertheless, they failed to show statistical significance. Conclusions: The next-generation sequencing-based family genomics approach described herein may serve as a paradigm towards the identification of novel functional variants with the aim of understanding complex disease pathobiology

DOCK8 Functions as an Adaptor that Links TLR–MyD88 Signaling to B Cell Activation

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

Natural Killer Cells from Patients with Recombinase-Activating Gene and Non-Homologous End Joining Gene Defects Comprise a Higher Frequency of CD56bright NKG2A+++ Cells, and Yet Display Increased Degranulation and Higher Perforin Content.

Mutations of the recombinase Activating Genes 1 and 2 (RAG1, RAG2) in humans are associated with a broad range of phenotypes. For patients with severe clinical presentation, hematopoietic stem cell transplantation (HSCT) represents the only curative treatment, however high rates of graft failure and incomplete immune reconstitution have been observed, especially after unconditioned haploidentical transplantation. Studies in mice have shown that Rag-/- NK cells have a mature phenotype, reduced fitness and increased cytotoxicity. We aimed to analyze NK cell phenotype and function in patients with mutations in RAG and in non-homologous end joining (NHEJ) genes. Here we provide evidence that NK cells from these patients have an immature phenotype, with significant expansion of CD56bright CD16-/int CD57- cells, yet increased degranulation and high perforin content. Correlation was observed between in vitro recombinase activity of the mutant proteins, NK cell abnormalities, and in vivo clinical phenotype. Addition of serotherapy in the conditioning regimen, with the aim of depleting the autologous NK cell compartment, may be important to facilitate engraftment and immune reconstitution in patients with RAG and NHEJ defects treated by HSCT

The European internet-based patient and research database for primary immunodeficiencies: results 2006-2008

Primary immunodeficiencies (PID) are rare diseases; therefore transnational studies are essential to maximize the scientific outcome and to improve diagnosis and therapy. In order to estimate the prevalence of PID in Europe as well as to establish and evaluate harmonized guidelines for the diagnosis and treatment of PID, the European Society for Immunodeficiencies (ESID) has developed an internet-based database for clinical and research data on patients with PID. This database is a platform for epidemiological analyses as well as the development of new diagnostic and therapeutic strategies and the identification of novel disease-associated genes. Within 4 years, 7430 patients from 39 countries have been documented in the ESID database. Common variable immunodeficiency (CVID) represents the most common entity, with 1540 patients or 20.7% of all entries, followed by isolated immunoglobulin (Ig)G subclass deficiency (546 patients, 7.4%). Evaluations show that the average life expectancy for PID patients varies from 1 to 49 years (median), depending on the type of PID. The prevalence and incidence of PID remains a key question to be answered. As the registration progress is far from finished we can only calculate minimum values for PID, with e.g. France currently showing a minimum prevalence of 3.72 patients per 100,000 inhabitants. The most frequently documented permanent treatment is immunoglobulin replacement; 2819 patients (42% of all patients alive) currently receive this form of treatment

Modeling, optimization, and comparable efficacy of T cell and hematopoietic stem cell gene editing for treating hyper-IgM syndrome

Precise correction of the CD40LG gene in T cells and hematopoietic stem/progenitor cells (HSPC) holds promise for treating X-linked hyper-IgM Syndrome (HIGM1), but its actual therapeutic potential remains elusive. Here, we developed a one-size-fits-all editing strategy for effective T-cell correction, selection, and depletion and investigated the therapeutic potential of T-cell and HSPC therapies in the HIGM1 mouse model. Edited patients' derived CD4 T cells restored physiologically regulated CD40L expression and contact-dependent B-cell helper function. Adoptive transfer of wild-type T cells into conditioned HIGM1 mice rescued antigen-specific IgG responses and protected mice from a disease-relevant pathogen. We then obtained similar to 25% CD40LG editing in long-term repopulating human HSPC. Transplanting such proportion of wild-type HSPC in HIGM1 mice rescued immune functions similarly to T-cell therapy. Overall, our findings suggest that autologous edited T cells can provide immediate and substantial benefits to HIGM1 patients and position T-cell ahead of HSPC gene therapy because of easier translation, lower safety concerns and potentially comparable clinical benefits.Transplantation and immunomodulatio