CXCL8 and cystic fibrosis: In the long-term controlled trial of inhaled HTS in patients with CF performed by Elkins and colleagues (2006), measurements of the proinflammatory cytokines IL-6, IL-8, IL-10, and tumour necrosis factor-alpha (TNF-alpha) were made in sputum at the time of screening and several later points until 48 weeks after the implementation of HTS nebulisation [24].