clair088

The house dust mite (HDM) is present in human habitats around the globe, and it is a significant factor in allergic rhinitis and allergic asthma. Sensitization to mite allergens in early life compromises lung function and leads to wheezing in children, and it associates with poorer outcomes in a patient’s respiratory health in the long term. Calderón et al review the epidemiology of HDM allergy and the effect of HDM allergens on the human immune system ( J Allergy Clin Immunol 2015; 136(1): 38-48 ). Both assessing prevalence of HDM sensitivity and controlling a patient’s exposure to the allergen pose challenges. Prevalence data for HDM sensitization vary according to targeted population: from estimating 65 million to 130 million people in the global general population may be affected to as many as 50% of those with asthma. In addition, results vary within geographic locations, meaning studies have found significant differences in prevalence within a given country or region. In terms o...

Psoriasis is a chronic immune-mediated inflammatory skin disease with a global incidence of approximately 2%. The extent of the affected body surface area and degree of erythema, induration, and scaling in four areas define its severity, and approximately 25% of patients have moderate-to-severe disease. Genome-wide association studies have linked variants in the gene for the IL-23 receptor and the p19 subunit of IL-23 to psoriasis susceptibility. IL-23 induces differentiation of T H 17 cells and T H 22 cells. The former are a primary cellular source of proinflammatory cytokines, including IL-17, and the latter are a primary source of IL-22. Both interleukins can mediate the development of the epidermal hyperplasia and tissue inflammation that occurs in psoriasis. Krueger et al present the first-in-human proof-of-concept study to evaluate the clinical and biological effects of BI 655066 in patients with moderate-to-severe psoriasis. BI 655066 is a novel, fully human IgG 1 mAb selective...

Little is known about the mechanisms regulating the persistence of chronic asthma. Because many allergens are perennially present, it has been difficult to ascertain whether persistence depends on this proximity. Studies of patients with occupational asthma have shown they experience symptoms for years after occupational exposure has ended. Christianson et al developed a mouse model in which asthma persisted for six months after allergen exposure ceased. They then used a combination of immunologic, genetic, microarray, and pharmacologic approaches to identify the factors contributing to symptom persistence ( J Allergy Clin Immunol 2015; 136(1):59-68 ). The authors found increased ILC2 levels characterize chronic asthma. In addition, IL-33-driven ILC2s prove to be an essential factor. The blockade of epithelial IL-33 led to a complete resolution of airway hyperactivity and a significant reduction of airway inflammation. They found IL-13, a product of ILC2s, can induce production of IL-...

It is acknowledged that key events that determine risk for the development of allergic disease frequently occur years before manifestation of symptoms. Recent culture-based studies, in combination with population-wide bacterial metagenomic data, suggest that parallel bacterial interactions may contribute to disease development. Holt reviews these and related issues of immune competence in infancy ( J Allergy Clin Immunol 2015; 136(1): 15-22 ). A number of factors specific to  infancy can contribute to disease development. Prospective tracking of postnatal IgE titres in serum samples collected over the first five years of life strongly suggests IgE antibody production against aeroallergens rarely begins before the age of six months. Airway mucosal dendritic cells (AMDC) transmit aeroallergen-specific signals from the airway mucosal surface to the central immune system and program the balance between the Th2 and T regulatory cell components of the immunological memory that results. T...

Allergic reactions were virtually unknown prior to 1870, and this is still the case in pre-hygiene villages in parts of the world today. While it has been previously implied that the increase in allergic disease was unimodal, Platts-Mills traces how history indicates this is not the case. Hay fever was first reported in the UK and the United States in 1870, the first clear reports of an increase in pediatric asthma appeared in the 1970s, and the current epidemic of food allergy became apparent in the 1990s. In a fascinating review, Platts-Mills traces the emergence and development of respiratory and food allergies and asthma ( J Allergy Clin Immunol 2015; 136(1): 3-13 ). Sequential changes in agriculture and trade, hygiene, diet, lifestyle, and environment in the past 150 years have likely contributed to an increase in allergic disease. In England and the US in the latter half of the nineteen century and start of the twentieth century, cultivation of land and the introduction of non-na...