Ubiquitously expressed Human Beta Defensin 1 (hBD1) forms bacteria-entrapping nets in a redox dependent mode of action
Fig 5
Proof for functional net-formation of hBD1red.
Comparison of antimicrobial activity of different hBD1 forms. Antimicrobial activity of hBD1 forms was compared in a (A) turbidity broth assay or (B) RDA against K. pneumoniae. Different concentrations of peptides were incubated with bacteria and change in optical density (OD600) was measured after 12 h or the diameter of inhibition zone was analyzed. HBD1 redox forms are not antimicrobial active against K. pneumoniae. (C) Schematic model for the Transwell Membrane Assay. Bacteria are entrapped in a net and are not able to pass the porous membrane (left), but in absence of nets bacteria pass through the membrane and grow in the TSB medium in the chamber below. (D) Bacterial growth was measured at OD600 after 1 h pre-incubation of peptide in filter and additional 2 h and % growth of negative control was plotted. With net formation no significant numbers of bacteria are able to translocate which is in contrast to hBD1ox or hBD1red_Abu with no net formation. Representative blood agar plates are shown. Data are presented as mean +/- SEM of at least three independent experiments. The statistic was evaluated by using student’s t-test with ****p < 0.0001.