Dendritic Cell-Derived TSLP Negatively Regulates HIF-1α and IL-1β During Dectin-1 Signaling.

Thymic stromal lymphopoietin (TSLP) is a functionally pleotropic cytokine important in immune regulation, and TSLP dysregulation is associated with numerous diseases. TSLP is produced by many cell types, but has predominantly been characterized as a secreted factor from epithelial cells which activates dendritic cells (DC) that subsequently prime T helper (T) 2 immunity. However, DC themselves make significant amounts of TSLP in response to microbial products, but the functional role of DC-derived TSLP remains unclear.

Surveillance study on the tolerability and safety of Flebogamma DIF (10% and 5% intravenous immunoglobulin) in adult and pediatric patients.

Direct comparisons of tolerability and safety of concentrated intravenous immunoglobulin (IVIG) versus less concentrated products are scarce. In this postauthorization, prospective, observational, multicenter study, a systematic comparison of 10% and 5% concentrations of Flebogamma® DIF IVIG was performed in both adult and pediatric patients treated with the studied IVIG products according to the approved indications under routine conditions. Dose of product administered, adverse events (AEs), physical assessments, laboratory tests, and concomitant therapy were analyzed.

Targeted Gene Panel Sequencing for Early-onset Inflammatory Bowel Disease and Chronic Diarrhea.

Background: In contrast to adult-onset inflammatory bowel disease (IBD), where many genetic loci have been shown to be involved in complex disease etiology, early-onset IBD (eoIBD) and associated syndromes can sometimes present as monogenic conditions. As a result, the clinical phenotype and ideal disease management in these patients often differ from those in adult-onset IBD. However, due to high costs and the complexity of data analysis, high-throughput screening for genetic causes has not yet become a standard part of the diagnostic work-up of eoIBD patients.

β-Glucan Size Controls Dectin-1-Mediated Immune Responses in Human Dendritic Cells by Regulating IL-1β Production.

Dectin-1/CLEC7A is a pattern recognition receptor that recognizes β-1,3 glucans, and its stimulation initiates signaling events characterized by the production of inflammatory cytokines from human dendritic cells (DCs) required for antifungal immunity. β-glucans differ greatly in size, structure, and ability to activate effector immune responses from DC; as such, small particulate β-glucans are thought to be poor activators of innate immunity. We show that β-glucan particle size is a critical factor contributing to the secretion of cytokines from human DC; large β-glucan-stimulated DC generate significantly more IL-1β, IL-6, and IL-23 compared to those stimulated with the smaller β-glucans.

Gene therapy for Wiskott-Aldrich syndrome in a severely affected adult.

Until recently, hematopoietic stem cell transplantation was the only curative option for Wiskott-Aldrich syndrome (WAS). The first attempts at gene therapy for WAS using a ϒ-retroviral vector improved immunological parameters substantially but were complicated by acute leukemia as a result of insertional mutagenesis in a high proportion of patients. More recently, treatment of children with a state-of-the-art self-inactivating lentiviral vector (LV-w1.

Detection of a microbial metabolite by STING regulates inflammasome activation in response to Chlamydia trachomatis infection.

The innate immune system is a critical component of host defence against microbial pathogens, but effective responses require an ability to distinguish between infectious and non-infectious insult to prevent inappropriate inflammation. Using the important obligate intracellular human pathogen Chlamydia trachomatis; an organism that causes significant immunopathology, we sought to determine critical host and pathogen factors that contribute to the induction of inflammasome activation. We assayed inflammasome activation by immunoblotting and ELISA to detect IL-1β processing and LDH release to determine pyroptosis.

IRE1α mediates PKR activation in response to Chlamydia trachomatis infection.

Protein kinase RNA activated (PKR) is a crucial mediator of anti-viral responses but is reported to be activated by multiple non-viral stimuli. However, mechanisms underlying PKR activation, particularly in response to bacterial infection, remain poorly understood. We have investigated mechanisms of PKR activation in human primary monocyte-derived dendritic cells in response to infection by Chlamydia trachomatis.

EBV-driven diffuse large B-cell lymphoma confined to the liver in a patient with a history of idiopathic CD4 lymphocytopenia.

Idiopathic CD4 lymphocytopenia (ICL) is a rare immunodeficiency disorder. We describe a 49-year-old woman with a history of ICL who developed hepatic Epstein-Barr virus (EBV)-positive diffuse large B-cell lymphoma (DLBCL). ICL was diagnosed at a time of her presentation with varicella-zoster virus (VZV) meningoencephalitis and chorioretinitis.

Clinical outcome in IL-10- and IL-10 receptor-deficient patients with or without hematopoietic stem cell transplantation.

Background: Inherited deficiencies of IL-10 or IL-10 receptor (IL-10R) lead to immune dysregulation with life-threatening early-onset enterocolitis.

Objectives: We sought to gather clinical data of IL-10/IL-10R-deficient patients and devise guidelines for diagnosis and management, including hematopoietic stem cell transplantation (HSCT).

Methods: We enrolled 40 patients with early-onset enterocolitis and screened for mutations in IL10/IL10R using genetic studies, functional studies, or both of the IL-10 signaling pathway.

Common variable immunodeficiency with coexisting central nervous system sarcoidosis: case report and literature review with implications for diagnosis and pathogenesis.

We describe a patient with a history of longstanding primary generalised epilepsy, on anticonvulsant therapy, who presented with fever, headache, worsening seizures and hallucinations. Among various investigations, the patient had high CSF protein and ACE levels, leptomeningeal nodular enhancement on MRI brain and non-caseating granulomas in the brain and meninges on the biopsy. The patient was diagnosed with neurosarcoidosis.

Influence of cytomegalovirus infection on immune cell phenotypes in patients with common variable immunodeficiency.

Background: A subset of patients with common variable immunodeficiency (CVID) have debilitating inflammatory complications strongly associated with cytomegalovirus (CMV) infection and a hyperproliferative CMV-specific T-cell response.

Objectives: We studied the T-cell response to CMV and the global effect of this virus on immune effector cell populations in patients with CVID.

Methods: Antibody staining, peptide stimulation, and proliferation assays were used to profile CMV-specific T-cell function.

Escape of Mycobacterium tuberculosis from oxidative killing by neutrophils.

Neutrophils enter sites of infection, where they can eliminate pathogenic bacteria in an oxidative manner. Despite their predominance in active tuberculosis lesions, the function of neutrophils in this important human infection is still highly controversial. We observed that virulent Mycobacterium tuberculosis survived inside human neutrophils despite prompt activation of these defence cells' microbicidal effectors.

Inflammation in common variable immunodeficiency is associated with a distinct CD8(+) response to cytomegalovirus.

Background: Common variable immunodeficiency is the most common primary immunodeficiency. A subset of patients has debilitating inflammatory complications.

Objectives: We investigated the role of cytomegalovirus (CMV), and the T-cell response targeted at this virus, in this inflammatory disease.

Serum trough IgG level and annual intravenous immunoglobulin dose are not related to body size in patients on regular replacement therapy.

Therapeutic regimens of intravenous immunoglobulin are currently based on actual body weight. The relationship between immunoglobulin dose and serum IgG level in relation to body size was retrospectively explored in patients on replacement therapy. Data were collected as part of a national audit on immunoglobulin therapy in patients with common variable immunodeficiency.

Impaired macrophage function following bacterial stimulation in chronic granulomatous disease.

Nicotinamide adenine dinucleotide phosphate (NADPH) oxidase is critical for phagocyte anti-microbial activity and plays a major role in innate immunity. Defects in genes coding for components of the NADPH oxidase enzyme system are responsible for chronic granulomatous disease (CGD), a rare primary neutrophil immunodeficiency associated with recurrent, life-threatening bacterial and fungal infections. Microbial killing and digestion within the neutrophil phagosomal compartment are defective in these patients.

Hypogammaglobulinaemia.

This article reviews the primary immunodeficiencies that result in hypogammaglobulinemia or predominantly antibody deficiency disorders. This group makes up the largest proportion of patients with primary immunodeficiency. Significant advances have been made in understanding the molecular basis and clinical characteristics of patients with the more severe forms of antibody deficiency in the last 6 years.

Common variable immunodeficiency: an update on etiology and management.

Common variable immunodeficiency (CVID) represents a heterogeneous group of primary antibody deficiency disorders characterized by recurrent infection and by inflammatory, granulomatous, and autoimmune complications. Recently, there have been significant advances in understanding the pathogenesis of the disease, with five genetic mutations identified in patients who have a CVID phenotype. Clinical care also has progressed with refinements in treatment and the development of classification schemes for prognostic and research purposes.