Development and qualification of an LC-MS/MS method for the quantification of MUC5AC and MUC5B mucins in spontaneous human sputum

Abstract

Aim: Airway mucins are promising biomarkers in respiratory diseases. In this study, we aimed to identify a suitable sputum collection and processing method, as well as qualify a bioanalytical method for soluble MUC5AC and MUC5B quantification in clinical samples. Method: Mucins were quantified in induced and spontaneous sputum collected from the same COPD patients and following various sample processing procedures. Our LC-MS/MS method used truncated recombinant mucins as surrogate analytes and a surrogate matrix approach. Results: Frozen spontaneous sputum was found to be a suitable and convenient matrix for mucin quantification and fit-for-purpose method qualification was performed. Conclusion: Our methodology provides accurate and reliable MUC5AC and MUC5B quantification and facilitates multi-site clinical studies in COPD and potentially other respiratory diseases.