clair088

Asthma management involves achieving and maintaining current asthma control and preventing exacerbations. Reports have shown, however, that there can be a disassociation between these two goals, meaning control may be achieved but risk of exacerbations may remain, or the opposite. The identification of patients at risk of future severe exacerbations, whose asthma might be less treatment-responsive, or both could focus treatment selection. To this end, Bateman et al have developed a simple risk score for exacerbations (RSE) for clinical use ( J Allergy Clin Immunol 2015; 135(6): 1457-64 ). The authors analyzed a large data set of patients enrolled in studies comparing the efficacy of budesonide-formoterol (BUD/FORM) maintenance and reliever therapy with fixed-dose inhaled corticosteroid/long-acting β 2 -agonist (ICS/LABA) therapy. They included patients whose symptoms were not controlled on Global Initiative for Asthma (GINA) treatment steps 3 and 4 and who had experienced 1 or more ex...

Platelet-activating factor (PAF) is a potent phospholipid-derived mediator thought to play a pivotal role in the etiology of numerous immune and inflammatory conditions. Our knowledge of its effects has broadened to include those as a vasodilator and broncho-constrictor, a contributor to host defenses, and a mediatory of the inflammatory response, and PAF has been well-demonstrated in experimental models to function as a central mediator of anaphylaxis. Gill et al review what we know ( J Allergy Clin Immunol 2015; 135(6): 1424-32 ). PAF is produced and secreted by several types of cells including mast cells, monocytes, tissue macrophages, eosinophils, endothelial cells, neutrophils, and platelets. It is implicated in platelet aggregation and activation through release of vasoactive amines in the inflammatory response, resulting in effects including increased vascular permeability, circulatory collapse, and decreased cardiac output. Studies have shown patients with acute allergic react...

Platelets are anucleated blood elements involved in hemostasis and thrombosis. It is now understood that they can also act as inflammatory cells and contribute to host defense against infection, performing many functions normally associated with leukocytes. Studies have shown that platelet depletion compromises ability to resist microorganism infection. Given that many inflammatory diseases are the result of inappropriate activation of defense pathways, it is likely inappropriate platelet activation contributes to the pathogenesis of these diseases. Idzko et al present the currently available data investigating the role of platelets in allergic airway inflammation and asthma ( J Allergy Clin Immunol 2015; 135(6): 1416-23 ). Of particular relevance to allergic inflammation, it has been shown that platelets express IgE receptors on their surfaces. They play an essential role in killing certain parasites, and platelet activation has been shown to accompany allergen exposure of sensitized...

Aspirin-exacerbated respiratory disease (AERD) is an acquired syndrome that is irreversible and debilitating. A chronic inflammatory disease characterized by the triad of asthma, nasal polyposis, and pathognomonic respiratory reactions after the ingestion of aspirin, it presents with an onset in young adulthood. Estimations indicate there are approximately 1.2 million adults in the United States living with AERD. Its pathogenesis likely involves disturbances in the mechanisms that regulate tissue recruitment of immune effector cells and activity of the 5-LO/LTC 4 S pathway. There is substantial evidence that platelets contribute to these mechanisms. Laidlaw et al review the evidence regarding asthma in general and AERD in particular ( J Allergy Clin Immunol 2015; 135(6): 1407-14 ). Platelets lack a nucleus and have no DNA. They are derived from cytoplasmic fragments of megakaryocytes and have a life span in the circulation of approximately 8-10 days before being removed by the spleen....