A number of studies have identified PTMs on the S100A8 and S100A9 subunits detected in specimens from humans including saliva, bronchial lavage fluid (BALF), sputum from cystic fibrosis (CF) patients, serum, plasma, nasal mucus, pimple pus, and kidney stones (Table 1). This evidence concerns the gene S100A8 and cystic fibrosis.