Figure 1

Spraying of U937 cells. (a) Schematic overview of the cell spraying procedure and (b) image of the pump spray devices used for our studies. (c) Numbers of viable and dead U937 cells after the spraying process, analyzed via trypan blue staining. Initial concentrations of 6 × 10⁶ cells/mL (left) and 12 × 10⁶ cells/mL (right) were used (significance of **P < 0.01 or ****P < 0.0001 by two-tailed paired student t-test, n = 3–6 mean ± SEM). (d) Cell numbers/puff at a cell concentration of 6 × 10⁶ cells/mL (n = 6, mean ± SEM). (e) Evaluation of cell viability after the spraying process by propidium iodide (PI) staining (Left: Representative flow cytometry analysis. Right: Quantification of cell viability n = 3 mean ± SEM). (n.s: denotes not significant. Statistical analysis: analyzed by two-way repeated measurements (RM) ANOVA with Bonferroni post-hoc-test).