Several chronic inflammatory airway diseases are characterized by an increased number of neutrophils in the airways. There is evidence that the recruitment of these neutrophils can be controlled by certain T-lymphocytes. However, the mechanisms behind this T-cell control of airway neutrophilia are poorly understood. In this review, we summarize the evidence that interleukin (IL)-17 released from T-lymphocytes of the CD45RO+ subset can link the activation of these T-cells to the recruitment and activation of neutrophils. This evidence suggests that pharmacotherapeutical modulation of neutrophilic airway inflammation can be achieved using several different strategies, including inhibition of IL-17 production by cAMP elevating agents or certain nuclear factor inhibitors, neutralization of released IL-17 protein by specific anti-IL-17-antibodies, blockade of the IL-17 receptor as well as inhibition of certain MAP kinases mediating the post receptor effects of IL-17 in airway cells. Additional studies on animals in vivo and patients, respectively, are needed to further evaluate the pharmacotherapeutical potential of these strategies.
Keywords: potential target, neutrophilia, epithelial damage, cytokine receptor, kidney carcinoma epithelial cells, airway neutrophils