Figure 3.

rTsSERP1 impairs neutrophil phagocytosis. The phagocytosis of neutrophils was induced by 100 nM of fMLP prior to treatment with 10 µg/ml of rTsSERP1 or an irrelevant control (rmDHFR), followed by incubation with the fluorescent E. coli BioParticle. After incubation, the fluorescent signal was measured and subsequently calculated as the percentage of phagocytosis (A). Neutrophils treated with fMLP alone were set as 100% phagocytotic effect. The bar charts show the data of three different donors, which are presented as the mean ± SD. The experiments were performed in triplicate with three independent experiments. One-way ANOVA followed by a Bonferroni multiple comparison test were used for statistical analysis: **p < 0.01 and ***p < 0.001. Fluorescent images (B) were captured to confirm the above result. The percentage of phagocytosis positive out of the total number of alive neutrophils was indicated in the merge of picture. The E. coli BioParticle was labeled with FITC (green) and the nucleus was counterstained with Hoechst 33342 (blue). Examples of non-phagocytotic neutrophils are indicated by white arrows. The treatment conditions were included media alone (Mock), only fMLP induction (fMLP), fMLP induction and rTsSERP1 treatment (rTsSERP1+fMLP), fMLP induction and irrelevant control (rmDHFR) treatment (rmDHFR+fMLP).