IL4 and asthma: Therefore, the main focus of asthma research groups during the last decades has been the type 2 inflammatory responses, where T lymphocytes play a prominent role in the pathogenesis, in particular T-helper cells type 2 (TH2), their transcription factors and cytokines, e.g., Interleukin-4 (IL-4), IL-5 and IL-13 (1–5).