Mass spectrometry analysis of IL-8(1-77) and IL-8(7-77).

IL-8(1-77) (A) and IL-8(7-77) (B) were desalted and subjected to electrospray mass spectrometry analysis to exclude the possibility of carboxyterminal cleavage by gelatinase B. Unprocessed (m/z) and charge-deconvoluted (m) spectra are shown. Theoretical masses of IL-8(1-77) and IL-8(7-77) are 8922.5 d and 8298.7 d, respectively. In the left panels, the m/z values for the differently charged ions are indicated, as are the number of protons (H⁺) they carry.