C-Terminal Alpha-1 Antitrypsin Peptide: A New Sepsis Biomarker with Immunomodulatory Function

Figure 2

The hairpin structure of CAAP48 is responsible for the function of the peptide. For identification of the functional domain of the peptide, we incubated fresh isolated PMN with the hairpin peptide and the sequence until the hairpin (u-hairpin) for 30 min. Cells were analyzed for surface expression of CD66b, CD63, CD69, and CD62L by flow cytometry. The hairpin peptide activates PMN, while the u-hairpin peptide shows no activation. Differential expression of activation markers is shown in histograms of one representative experiment out of four independent experiments using peptide concentrations of 40 µM.