IL21 and chronic obstructive pulmonary disease: Detailed analysis of a variety of other anti-inflammatory biological markers, such as IL-6, IL-12, IL-17, IL-21, nuclear factor-kappa (NF-B), and interferon-gamma (IFN-), to gain a more integrated understanding of the impact of sublingual glutathione on other inflammatory mediators associated with COPD and whether it is capable of mitigating COPD exacerbating episodes [34-36].