LTF and chronic obstructive pulmonary disease: A complex picture emerges from the study of different sputum antimicrobial substances in COPD exacerbations associated with nontypeable Haemophilus influenzae (NTHI) and Moraxella catarrhalis; compared to the baseline, lysozyme and SLPI lowered, LL-37 increased, and lactoferrin remained unchanged [227].