Emerging Cytokines in Allergic Airway Inflammation: A Genetic Update

Purpose: We aim to discuss the current status of knowledge on the role of recently identified cytokines in airway hyper responsiveness as well as the genetic predisposition conferred by their coding genes to asthma. Methods: We focused on three cytokines and their coding genes,IL-9, IL-17, and IL-22, and conducted a narrative review of all the relevant publications known to the authors. Results: A great body of evidence regarding the involvement of these three cytokines in asthma was discussed and interpreted. These range from studies on the murine models of asthma to clinical and human genetic approaches. Despite the large amounts of information existing on the genetics of IL-9 and IL-17, there is a lacking trend towards the IL-22 genetic studies in asthma. Conclusion: The emergence of new classes of T-helper effector cells and their cytokines has led to a change in our understanding of asthma pathogenesis. This has created both new opportunities and challenges for researchers involved in this field, and is likely to result in improvements and progress in identifying and developing novel therapeutic measures and innovative treatments for asthma.