Amir Hossein Massoud

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BACKGROUND Intravenous immunoglobulin (IVIg) is a polyclonal IgG preparation with potent immunomodulating properties. Our laboratory demonstrated that IVIg significantly increases numbers of forkhead box protein 3-positive regulatory T (Treg) cells through generation of tolerogenic dendritic cells (DCs) in an allergic airways disease model. OBJECTIVE We(More)
BACKGROUND Intravenous immunoglobulin (IVIG) is a frequently used disease-modifying therapy for a large spectrum of autoimmune and inflammatory conditions, yet its mechanisms of action are incompletely understood. Using a robust murine model of antigen-driven allergic airways disease, we have demonstrated that IVIG markedly improves ovalbumin (OVA)-induced(More)
IVIg is widely used as an immunomodulatory therapy. We have recently demonstrated that IVIg protects against airway hyperresponsiveness (AHR) and inflammation in mouse models of allergic airways disease (AAD), associated with induction of Foxp3+ regulatory T cells (Treg). Using mice carrying a DTR/EGFP transgene under the control of the Foxp3 promoter(More)
Methods Mice were sensitized (i.n.) with OVA and then received IVIg or sialic acid enriched IVIg (SA-IVIg) fragments (i.p.), and then underwent challenge (i.n.). The induction of CD4CD25Foxp3Treg was determined by flowcytometry. AHR was measured, using a flexiVent small animal ventilator. Phenotypic properties of dendritic cells (DC) from various(More)
Background IVIg is a polyclonal IgG preparation with potent immune-modulating properties. We demonstrated that IVIg protects against airway hyperreactivity (AHR) and airway inflammation in mouse models of allergic airway disease, accompanied by peripheral induction of Foxp3 regulatory T-cells (iTreg). The requirement of IVIginduced iTreg and their(More)
Programmed cell death-1 (PD-1, Pdcd1), an immunoreceptor belonging to the CD28/CTLA-4 family negatively regulates antigen receptor signalling by recruiting protein tyrosine phosphatase, SHP-2 upon interacting with either of two ligands, PD-L1 or PD-L2. This study investigates PD-1 gene polymorphism in patients with antisperm antibody-related infertility(More)
Mechanisms by which regulatory T (Treg) cells fail to control inflammation in asthma remain poorly understood. We show that a severe asthma-associated polymorphism in the gene encoding the interleukin (IL)-4 receptor alpha chain (Il4raR576) promotes conversion of induced Treg (iTreg) cells toward a T helper 17 (TH17) cell fate. This skewing is mediated by(More)
Aspirin gained tremendous popularity during the 1918 Spanish Influenza virus pandemic, 50 years prior to the demonstration of their inhibitory action on prostaglandins. Here, we show that during influenza A virus (IAV) infection, prostaglandin E2 (PGE2) was upregulated, which led to the inhibition of type I interferon (IFN) production and apoptosis in(More)
BACKGROUND Intravenous immunoglobulin (IVIG) has potent anti-inflammatory and immune-modulating properties. IVIG has been utilized as a steroid-sparing agent in severe asthma, but the results of clinical trials have been conflicting. OBJECTIVE To determine whether IVIG is able to attenuate bronchial reactivity, pulmonary inflammation and T cell function(More)
The regulatory properties of B cells have been studied in autoimmune diseases; however, their role in allergic diseases is poorly understood. We demonstrate that Semaphorin 4C (Sema4C), an axonal guidance molecule, plays a crucial role in B cell regulatory function. Mice deficient in Sema4C exhibited increased airway inflammation after allergen exposure,(More)