LAUSR

In recent years new treatments that go further than conventional therapeutical approaches (i.e. bronchodilators and classical antoinflammatory drugs) have been developed for COPD. Bronchodilators are used to try to increase the size of the airway and improve symptoms, while anti-inflammatories, mainly corticosteroids and phosphodiesterase 4 (PDE4) inhibitors, are aimed at reducing inflammation, one of the most significant pathogenic mechanisms in COPD. The new treatments, called “biologics” or “biological response modifiers” (BRM), act by neutralizing or modulating the function of certain molecular targets, and thus have a more specific anti-inflammatory action. To date, they have been developed and used mainly in bronchial asthma and lung cancer, but they are now also appearing on the horizon for the treatment of COPD. We know that in COPD, the airway develops an inflammatory response to various noxious stimuli (tobacco smoke, particles/gases, microorganisms), which by activating Toll-like receptors (TLRs), cause the recruitment of multiple immune system cells (predominantly neutrophils) and the secretion of inflammatory mediators.1 The typical immunological response in COPD is thought to be mediated mainly by the helper and cytotoxic T cell subsets (Th1/Tc2).2 In the case of asthma-COPD overlap (ACO), other co-activating noxious stimuli, such as allergens, are probably involved, with eosinophils playing an active role in this response. The most important inflammatory mediators include cytokines, chemokines and growth factors, those most probably involved in COPD being tumor necrosis factor (TNF), interleukin (IL)-1 , IL4, IL-5, IL-6, IL-8, IL-13, IL-18, IL-23, IL-33, eotaxin (CCL)-1, thymic stromal lymphopoietin (TSLP), and transforming growth factor (TGF).1,3,4 Most biological therapies are based on the administration of antibodies against these mediators or their receptors, although inhibitors, mostly of kinases, are also used; and it seems likely that in the near future even modulators of the pulmonary microbiota will be added to the range of available biological treatments.