CXCL8 and cystic fibrosis: In CF, in addition to IL-8/IL8R derived signaling, other pathways such as the CXCR4/CXCL12 axis and the oxygen-dependent transcription factor hypoxia-inducible factor-1α (HIF-1α) might concur in prolonging the lifespan of neutrophils consequently increasing the neutrophilic infiltration [76,79,80].