The Role of Dendritic Cells in Immune Regulation and Allergic Airway Inflammation

Dendritic cells (DC) are potent antigen presenting cells that display an extraordinary capacity to present antigen to naïve T-cells and initiate primary immune responses. In the context of the lung and upper airway it is clear that DC play a key role in the regulation of adaptive immune responses to inhaled antigen. DC are particularly sensitive to signals derived from microbes, allergens and the airway tissue microenvironment. By the nature of the signals they provide at the time of antigen presentation, DC can polarize naïve T-cells into either T-helper type 1 (Th1) or Th2 effector cells, and are increasingly recognized as having a central role in the establishment of T-cell memory and peripheral immune tolerance. DC form a network within the upper airway and lung, and are rapidly recruited from the circulation in response to a variety of proinflammatory stimuli. Studies using animal models have highlighted the role of DC in both the initiation and maintenance of allergic airway inflammation. In early childhood, human DC are functionally immature, and this is thought to contribute to the development of allergic sensitization in those children who are genetically at risk for the development of atopy. Increased numbers of airway mucosal DC are found in both allergic rhinitis and asthma, while studies of blood-derived DC have emphasized important differences between the function of DC from atopic and normal individuals. This article reviews recent information on the involvement of DC in allergic airway disease, and the mechanisms by which DC could be exploited as targets for therapy in asthma and allergic rhinitis

Joint American Academy of Dermatology-National Psoriasis Foundation guidelines of care for the management and treatment of psoriasis with phototherapy

Psoriasis is a chronic inflammatory disease involving multiple organ systems and affecting approximately 3.2% of the world\u27s population. In this section of the guidelines of care for psoriasis, we will focus the discussion on ultraviolet (UV) light-based therapies, which include narrowband and broadband UVB, UVA in conjunction with photosensitizing agents, targeted UVB treatments such as with an excimer laser, and several other modalities and variations of these core phototherapies, including newer applications of pulsed dye lasers, intense pulse light, and light-emitting electrodes. We will provide an in-depth, evidence-based discussion of efficacy and safety for each treatment modality and provide recommendations and guidance for the use of these therapies alone or in conjunction with other topical and/or systemic psoriasis treatments