Remarkably (and likely related to the increased numbers of LDNs in CF PBMCs), the only mediators present behaving differently, i.e demonstrating an increased response to PMA/iono stimulation in CF cells, were the metalloproteases MMP-8 and MMP-9 (present in neutrophil secondary and tertiary granules, respectively (Figures 6E, F). Here, MMP8 is linked to cystic fibrosis.