Helen M. Chapel

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The European Common Variable Immunodeficiency Disorders registry was started in 1996 to define distinct clinical phenotypes and determine overlap within individual patients. A total of 7 centers contributed patient data, resulting in the largest cohort yet reported. Patients (334), validated for the diagnosis, were followed for an average of 25.6 years(More)
The heterogeneity of common variable immunodeficiency (CVID) calls for a classification addressing pathogenic mechanisms as well as clinical relevance. This European multicenter trial was initiated to develop a consensus of 2 existing classification schemes based on flowcytometric B-cell phenotyping and the clinical course. The clinical evaluation of 303(More)
The functional interaction of BAFF and APRIL with TNF receptor superfamily members BAFFR, TACI and BCMA is crucial for development and maintenance of humoral immunity in mice and humans. Using a candidate gene approach, we identified homozygous and heterozygous mutations in TNFRSF13B, encoding TACI, in 13 individuals with common variable immunodeficiency.(More)
The common variable immunodeficiency disorders are a mixed group of heterogeneous conditions linked by lack of immunoglobulin production and primary antibody failure. This variability results in difficulty in making coherent sense of either immunopathogenesis or the role of various genetic abnormalities reported in the literature. The recent attempt to(More)
To compare the efficacy of immunoglobulin replacement therapy given intravenously versus subcutaneously to prevent infections in patients with primary antibody deficiency syndromes, an international, multicenter, open label, crossover study was designed. Forty patients were randomized to receive either subcutaneous or intravenous immunoglobulin replacement(More)
BACKGROUND Common variable immunodeficiency disorders (CVIDs) are the most common forms of symptomatic primary antibody failure in adults and children. Replacement immunoglobulin is the standard treatment, although there are few consistent data on optimal dosages and target trough IgG levels required for infection prevention. OBJECTIVE To provide data to(More)
MyD88 is a key downstream adapter for most Toll-like receptors (TLRs) and interleukin-1 receptors (IL-1Rs). MyD88 deficiency in mice leads to susceptibility to a broad range of pathogens in experimental settings of infection. We describe a distinct situation in a natural setting of human infection. Nine children with autosomal recessive MyD88 deficiency(More)
TNFRSF13B encodes transmembrane activator and calcium modulator and cyclophilin ligand interactor (TACI), a B cell- specific tumor necrosis factor (TNF) receptor superfamily member. Both biallelic and monoallelic TNFRSF13B mutations were identified in patients with common variable immunodeficiency disorders. The genetic complexity and variable clinical(More)
Intravenous immunoglobulin (IVIG) is used as the standard replacement therapy for patients with primary antibody deficiencies. A previous study of adverse reactions in patients self-infusing at home over 1 year showed an overall reaction rate of 0.7%. A larger prospective study is reported here, involving a greater number of immunology centres and including(More)
Intravenous immunoglobulin (IVIg) is a potential alternative treatment for anti-neutrophil cytoplasm antibody (ANCA)-associated systemic vasculitis (AASV) with less toxicity than conventional immunosuppressive agents. This randomized, placebo-controlled trial aimed to investigate the efficacy of a single course of IVIg (total dose 2 g/kg) in(More)